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2024arXiv240909029T

Cosmological models are often motivated and formulated in the language of particle physics using quantities such as the axion decay constant but tested against data using ostensibly physical quantities such as energy density ratios assuming uniform priors on the latter. This approach neglects priors on the model from fundamental theory including from particle physics and string theory such as the preference for subPlanckian axion decay constants. We introduce a novel approach to learning theoryinformed priors for Bayesian inference using normalizing flows NF a flexible generative machine learning technique that generates priors on model parameters when analytic expressions are unavailable or difficult to compute. As a test case we focus on early dark energy EDE a model designed to address the Hubble tension. Rather than using uniform priors on the textitphenomenological EDE parameters frm EDE and zc we train a NF on EDE cosmologies informed by theory expectations for axion masses and decay constants. Our method recovers known constraints in this representation while being sim 300000 times more efficient in terms of total CPU compute time. Applying our NF to textitPlanck and BOSS data we obtain the first theoryinformed constraints on EDE finding frm EDE lesssim 0.02 at 95 confidence with an H0 consistent with textitPlanck but in sim 6sigma tension with SH0ES. This yields the strongest constraints on EDE to date additionally challenging its role in resolving the Hubble tension.

2024-09-01T00:00:00Z

['2024arXiv240909029T', 'arXiv:2409.09029', '10.48550/arXiv.2409.09029']

['Astrophysics - Cosmology and Nongalactic Astrophysics', 'Astrophysics - Instrumentation and Methods for Astrophysics', 'High Energy Physics - Phenomenology', 'High Energy Physics - Theory']

Learning Theory Informed Priors for Bayesian Inference A Case Study with Early Dark Energy

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https://arxiv.org/pdf/2409.09029.pdf

2024arXiv240600923H

The existence of intermediatemass black holes IMBHs is crucial for understanding various astrophysical phenomena yet their existence remains elusive except for the LIGOVirgo detection. We report the discovery of a highvelocity star J07313717 whose backward trajectory about 21 Myr ago intersects that of globular cluster M15 within the cluster tidal radius. Both its metallicity FeH and its alphatoiron abundance ratio alphaFe are consistent with those of M15. Furthermore its location falls right on the fiducial sequence of the cluster M15 on the colorabsolute magnitude diagram suggesting similar ages. These support that J07313717 is originally associated with M15 at a confidence level of seven nines. We find that such a highvelocity star Vrm ej 54865 km s1 was most likely tidally ejected from as close as one astronomical unit to the center of M15 confirming an IMBH ge 100 Modot with a credibility of 98 as the exclusive nature of the central unseen mass proposed previously.

2024-06-01T00:00:00Z

['10.48550/arXiv.2406.00923', '2024arXiv240600923H', 'arXiv:2406.00923']

['Astrophysics - Astrophysics of Galaxies', 'Astrophysics - High Energy Astrophysical Phenomena', 'Astrophysics - Solar and Stellar Astrophysics']

A highvelocity star recently ejected by an intermediatemass black hole in M15

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https://arxiv.org/pdf/2406.00923.pdf

2024arXiv240907768G

While much supersymmetric WIMP parameter space has been ruled out one remaining important candidate is Higgsino dark matter. The Higgsino can naturally realize the inelastic dark matter scenario where the scattering off a nucleus occurs between two nearlydegenerate states making it invisible to WIMP direct detection experiments if the splitting is too large to be excited. It was realized that a luminous dark matter detection process where the Higgsino upscatters in the Earth and subsequently decays into a photon in a large neutrino detector offers the best sensitivity to such a scenario. We consider the possibility of adding a large volume of a heavy element such as Pb or U around the detector. We also consider the presence of U and Th in the Earth itself and the effect of an enhanced highvelocity tail of the dark matter distribution due to the presence of the Large Magellanic Cloud. These effects can significantly improve the sensitivity of detectors such as JUNO SNO and Borexino potentially making it possible in the future to cover much of the remaining parameter space for this classic SUSY WIMP dark matter.

2024-09-01T00:00:00Z

['arXiv:2409.07768', '10.48550/arXiv.2409.07768', '2024arXiv240907768G']

['High Energy Physics - Phenomenology', 'Astrophysics - Cosmology and Nongalactic Astrophysics', 'High Energy Physics - Experiment']

Enhancing Direct Detection of Higgsino Dark Matter

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https://arxiv.org/pdf/2409.07768.pdf

2024arXiv240912943A

In this paper we construct the classical phase space of JackiwTeitelboim gravity with positive cosmological constant on spatial slices with circle topology. This turns out to be somewhat more intricate than in the case of negative cosmological constant this phase space has many singular points and is not even Hausdorff. Nonetheless it admits a grouptheoretic description which is quite amenable to quantization.

2024-09-01T00:00:00Z

['arXiv:2409.12943', '10.48550/arXiv.2409.12943', '2024arXiv240912943A']

['High Energy Physics - Theory', 'General Relativity and Quantum Cosmology']

Phase space of JackiwTeitelboim gravity with positive cosmological constant

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https://arxiv.org/pdf/2409.12943.pdf

2024NatAs.tmp..215W

The mass distribution of black holes identified through Xray emission suggests a paucity of black holes in the mass range of 3 to 5 solar masses. Modified theories have been devised to explain this mass gap and it is suggested that natal kicks during a supernova explosion can more easily disrupt binaries with lowermass black holes. Although recent Laser Interferometer GravitationalWave Observatory observations reveal the existence of compact remnants within this mass gap the question of whether lowmass black holes can exist in binaries remains a matter of debate. Such a system is expected to be noninteracting and without Xray emission and can be searched for using radialvelocity and astrometric methods. Here we report on Gaia Data Release 3 DR3 3425577610762832384 which is a wide binary system that includes a red giant star and an unseen object exhibiting an orbital period of approximately 880 days and a nearzero eccentricity. Through the combination of radialvelocity measurements from the Large Aperture MultiObject Spectroscopic Telescope and astrometric data from Gaia DR2 and DR3 catalogues we determine a mass of 3 .6SUB0.5SUBSUP0.8SUPMSUBSUB of the unseen component. If the unseen companion is a black hole its mass would fall within the gap and it would strongly suggest the existence of binary systems containing lowmass black holes. More notably the formation of its surprisingly wide circular orbit challenges current binary evolution and supernova explosion theories.

2024-09-01T00:00:00Z

['2024NatAs.tmp..215W', '10.1038/s41550-024-02359-9', 'arXiv:2409.06352', '10.48550/arXiv.2409.06352', '2024arXiv240906352S']

['Astrophysics - Solar and Stellar Astrophysics', 'Astrophysics - High Energy Astrophysical Phenomena']

A potential massgap black hole in a wide binary with a circular orbit

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https://arxiv.org/pdf/2409.06352.pdf

2024arXiv240904580A

We present a complete analysis of Fermi Large Area Telescope LAT data of GRB 221009A the brightest GammaRay Burst GRB ever detected. The burst emission above 30 MeV detected by the LAT preceded by 1 s the lowenergy lt 10 MeV pulse that triggered the Fermi GammaRay Burst Monitor GBM as has been observed in other GRBs. The prompt phase of GRB 221009A lasted a few hundred seconds. It was so bright that we identify a Bad Time Interval BTI of 64 seconds caused by the extremely high flux of hard Xrays and soft gamma rays during which the event reconstruction efficiency was poor and the dead time fraction quite high. The latetime emission decayed as a power law but the extrapolation of the latetime emission during the first 450 seconds suggests that the afterglow started during the prompt emission. We also found that highenergy events observed by the LAT are incompatible with synchrotron origin and during the prompt emission are more likely related to an extra component identified as synchrotron selfCompton SSC. A remarkable 400 GeV photon detected by the LAT 33 ks after the GBM trigger and directionally consistent with the location of GRB 221009A is hard to explain as a product of SSC or TeV electromagnetic cascades and the process responsible for its origin is uncertain. Because of its proximity and energetic nature GRB 221009A is an extremely rare event.

2024-09-01T00:00:00Z

['arXiv:2409.04580', '10.48550/arXiv.2409.04580', '2024arXiv240904580A']

['Astrophysics - High Energy Astrophysical Phenomena']

GRB 221009A the B.O.A.T Burst that Shines in Gamma Rays

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https://arxiv.org/pdf/2409.04580.pdf

2024arXiv240806153F

We present the latest results from the Chicago Carnegie Hubble Program CCHP to measure the Hubble constant using data from the James Webb Space Telescope JWST. This program is based upon three independent methods 1 Tip of the Red Giant Branch TRGB stars 2 JAGB JRegion Asymptotic Giant Branch stars and 3 Cepheids. Our program includes 10 nearby galaxies each hosting Type Ia supernovae suitable for measuring the Hubble constant Ho. It also includes NGC 4258 which has a geometric distance setting the zero point for all three methods. The JWST observations have significantly higher signaltonoise and finer angular resolution than previous observations with the Hubble Space Telescope HST. We find three independent values of Ho 69.85 1.75 stat 1.54 sys for the TRGB Ho 67.96 1.85 stat 1.90 sys for the JAGB and Ho 72.05 1.86 stat 3.10 sys kmsMpc for Cepheids. Tying into supernovae and combining these methods adopting a flat prior yields our current estimate of Ho 69.96 1.05 stat 1.12 sys kmsMpc. The distances measured using the TRGB and the JAGB method agree at the 1 level but differ from the Cepheid distances at the 2.54 level. The value of Ho based on these two methods with JWST data alone is Ho 69.03 1.75 total error kmsecMpc. These numbers are consistent with the current standard Lambda CDM model without the need for the inclusion of additional new physics. Future JWST data will be required to increase the precision and accuracy of the local distance scale.

2024-08-01T00:00:00Z

['2024arXiv240806153F', '10.48550/arXiv.2408.06153', 'arXiv:2408.06153']

['Astrophysics - Cosmology and Nongalactic Astrophysics']

Status Report on the ChicagoCarnegie Hubble Program CCHP Three Independent Astrophysical Determinations of the Hubble Constant Using the James Webb Space Telescope

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https://arxiv.org/pdf/2408.06153.pdf

2024arXiv240912989C

It was recently claimed arXiv2409.09081v1 astroph.HE that accretion of ordinary matter on black holes of mass 6times 10144times1019g would be inhibited by quantum mechanical effects namely the de Broglie wavelength of the electron being larger than the Schwarzschild radius. However the conclusion is based on considering accretion of a single atom over the age of the Universe. There is no suppression of the accretion rate per atom on such black holes.

2024-09-01T00:00:00Z

['arXiv:2409.12989', '2024arXiv240912989C', '10.48550/arXiv.2409.12989']

['Astrophysics - High Energy Astrophysical Phenomena', 'General Relativity and Quantum Cosmology', 'High Energy Physics - Phenomenology']

Comment on QuantumMechanical Suppression of Gas Accretion by Primordial Black Holes

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https://arxiv.org/pdf/2409.12989.pdf

2024arXiv240906015C

One of the most compelling pieces of evidence of the Hot Big Bang model is the realisation and confirmation that some nuclides were created shortly after the Big Bang. This process is referred to as Big Bang nucleosynthesis or sometimes primordial nucleosynthesis and is the endproduct of putting neutrons and protons in a hot expanding Universe. Big Bang nucleosynthesis currently provides our earliest test of cosmology and it is the only experiment currently designed that is simultaneously sensitive to all four known fundamental forces the gravitational force the electromagnetic force the strong force and the weak force. Our theoretical understanding of Big Bang nucleosynthesis and the measurement of the primordial abundances together represents one of the strongest pillars of the standard cosmological model. In this chapter we will develop an intuitive understanding of Big Bang nucleosynthesis discuss modern calculations of this process and provide a summary of the current stateoftheart measurements that have been made. Overall Big Bang nucleosynthesis is in remarkable agreement with various cosmological probes and it is this agreement that serves to strengthen our confidence in the general picture of cosmology that we have today.

2024-09-01T00:00:00Z

['2024arXiv240906015C', '10.48550/arXiv.2409.06015', 'arXiv:2409.06015']

['Astrophysics - Cosmology and Nongalactic Astrophysics', 'Nuclear Experiment', 'Nuclear Theory']

Big Bang Nucleosynthesis

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https://arxiv.org/pdf/2409.06015.pdf

2019SCPMA..6229511Y

Major galaxy mergers can trigger nuclear activities and are responsible for highluminosity quasistellar objectsactive galactic nuclei QSOsAGNs. In certain circumstances such mergers may cause dual active galactic nuclei dAGN phenomenon. This study investigates dAGN triggering and evolution of massive black holes MBHs during the merging processes using hydro dynamic code GADGET2 to simulate several gasrich major mergers at redshift z 2 and 3 respectively. Results reveal that gasrich major mergers can trigger significant nuclear activities after the second and third pericentric passages and the formation of dAGN with significant time duration 10390 Myr. During the merging processes galactic bulge evolves with time because of the rapid star formation in each or both galactic centers and initial mixing of stars in galactic disks due to violent relaxation. MBHs grow substantially due to accretion and finally merge into a bigger black hole. The growth of galactic bulges and cor responding increases of its velocity dispersions predate the growth of MBHs in the dAGN stages. The MBHs in these stages deviate below the relation between MBH mass and bulge mass or velocity dispersion and they revert to the relation after the final mergers due to the significant accretion that occurs mostly at a separation less than a few kpc. Then the two MBHs merge with each other.

2019-12-01T00:00:00Z

['arXiv:2110.02139', '10.1007/s11433-019-9442-9', '2021arXiv211002139Y', '10.48550/arXiv.2110.02139', '2019SCPMA..6229511Y', '2019SCPMA..62l9511Y']

['galaxies', 'quasars', 'black hole', 'numerical simulations', 'Astrophysics - Astrophysics of Galaxies']

Investigating the coevolution of massive black holes in dual active galactic nuclei and their host galaxies via galaxy merger simulations

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https://arxiv.org/pdf/2110.02139.pdf

2024arXiv240906772T

We present a sample of 50 Halpha detected broadline active galactic nuclei BLAGN at redshifts 3.5ltzlt6.8 using data from the CEERS and RUBIES surveys. We select these sources directly from JWSTNIRSpec G395MF290LP spectra. We use a multistep preselection and a Bayesian fitting procedure to ensure a highquality sample of sources with broad Balmer lines and narrow forbidden lines. We compute restframe ultraviolet and optical spectral slopes for these objects and determine that 10 BLAGN in our sample are also little red dots LRDs. These LRD BLAGN when examined in aggregate show broader Halpha line profiles and a higher fraction of broadtonarrow component Halpha emission than nonLRD BLAGN. Moreover we find that 66 of these objects are intrinsically reddened beta opticalgt0 independent of the contributions of emission lines to the broadband photometry. We construct the black hole BH mass function at 3.5ltzlt6 after computing robust observational and line detection completeness corrections. This BH mass function shows broad agreement with both recent JWSTNIRSpec and JWSTNIRCam WFSS based BH mass functions though we extend these earlier results to logMBHMsun lt 7. The derived BH mass function is consistent with a variety of theoretical models indicating that the observed abundance of black holes in the early universe is not discrepant with physicallymotivated predictions. The BH mass function shape resembles a largely featureless powerlaw suggesting that any signature from blackhole seeding has been lost by redshift z56. Finally we compute the BLAGN UV luminosity function and find good agreement with JWSTdetected BLAGN samples from recent works finding that BLAGN hosts constitute lt10 of the total observed UV luminosity at all but the brightest luminosities.

2024-09-01T00:00:00Z

['10.48550/arXiv.2409.06772', 'arXiv:2409.06772', '2024arXiv240906772T']

['Astrophysics - Astrophysics of Galaxies']

BroadLine AGN at 3.5ltzlt6 The Black Hole Mass Function and a Connection with Little Red Dots

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https://arxiv.org/pdf/2409.06772.pdf

2024arXiv240905948D

We present the Red Unknowns Bright Infrared Extragalactic Survey RUBIES providing JWSTNIRSpec spectroscopy of red sources selected across 150 arcmin2 from public JWSTNIRCam imaging in the UDS and EGS fields. RUBIES novel observing strategy offers a wellquantified selection function the survey is optimised to reach high gt70 completeness for bright and red F150WF444Wgt2 sources that are very rare. To place these rare sources in context we simultaneously observe a reference sample of the 2ltzlt7 galaxy population sampling sources at a rate that is inversely proportional to their number density in the 3D space of F444W magnitude F150WF444W colour and photometric redshift. In total RUBIES observes 3000 targets across 1ltzphotlt10 with both the PRISM and G395M dispersers and 1500 targets at zphotgt3 using only the G395M disperser. The RUBIES data reveal a highly diverse population of red sources that span a broad redshift range zspecsim19 with photometric redshift scatter and outlier fraction that are 3 times higher than for similarly bright sources that are less red. This diversity is not apparent from the photometric SEDs. Only spectroscopy reveals that the SEDs encompass a mixture of galaxies with dustobscured star formation extreme line emission a lack of star formation indicating early quenching and luminous active galactic nuclei. As a first demonstration of our broader selection function we compare the stellar masses and restframe UV colours of the red sources and our reference sample red sources are typically more massive Msim101011.5 Modot across all redshifts. However we find that the most massive systems span a wide range in UV colour. We describe our data reduction procedure and data quality and publicly release the reduced RUBIES data and vetted spectroscopic redshifts of the first half of the survey through the DJA.

2024-09-01T00:00:00Z

['10.48550/arXiv.2409.05948', 'arXiv:2409.05948', '2024arXiv240905948D']

['Astrophysics - Astrophysics of Galaxies']

RUBIES a complete census of the bright and red distant Universe with JWSTNIRSpec

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https://arxiv.org/pdf/2409.05948.pdf

2024arXiv240907113O

Understanding the rapid formation of supermassive black holes SMBHs in the early universe requires an understanding of how stellar mass grows in the host galaxies. Here we perform an analysis of restframe optical spectra and imaging from JWST of two quasar host galaxies at zgt6 which exhibit Balmer absorption lines. These features in the stellar continuum indicate a lack of young stars similar to lowredshift poststarburst galaxies whose star formation was recently quenched. We find that the stellar mass logM Msun gt 10.6 of each quasar host grew in a starburst episode at redshift 7 or 8. One of the targets exhibits little ongoing star formation as evidenced by the photometric signature of the Balmer break and a lack of spatially resolved Halpha emission placing it well below the star formation main sequence at z 6. The other galaxy is transitioning to a quiescent phase together the two galaxies represent the most distant massive poststarburst galaxies known. The maturity of these two galaxies is further supported by the stellar velocity dispersions of their host galaxies placing them slightly above the upper end of the local MBH sigma relation. The properties of our two poststarburst galaxies each hosting an active SMBH with logMBH Msun gt 9 suggests that black holes played a major role in shaping the formation of the first massive galaxies in the Universe.

2024-09-01T00:00:00Z

['10.48550/arXiv.2409.07113', '2024arXiv240907113O', 'arXiv:2409.07113']

['Astrophysics - Astrophysics of Galaxies', 'Astrophysics - Cosmology and Nongalactic Astrophysics']

A PostStarburst Pathway to Forming Massive Galaxies and Their Black Holes at zgt6

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https://arxiv.org/pdf/2409.07113.pdf

2024arXiv240403002D

We present cosmological results from the measurement of baryon acoustic oscillations BAO in galaxy quasar and Lymanalpha forest tracers from the first year of observations from the Dark Energy Spectroscopic Instrument DESI to be released in the DESI Data Release 1. DESI BAO provide robust measurements of the transverse comoving distance and Hubble rate or their combination relative to the sound horizon in seven redshift bins from over 6 million extragalactic objects in the redshift range 0.1ltzlt4.2. DESI BAO data alone are consistent with the standard flat LambdaCDM cosmological model with a matter density Omegamathrmm0.295pm 0.015. Paired with a BBN prior and the robustly measured acoustic angular scale from the CMB DESI requires H068.52pm0.62 kmsMpc. In conjunction with CMB anisotropies from Planck and CMB lensing data from Planck and ACT we find Omegamathrmm0.307pm 0.005 and H067.97pm0.38 kmsMpc. Extending the baseline model with a constant dark energy equation of state parameter w DESI BAO alone require w0.990.150.13. In models with a timevarying dark energy equation of state parametrized by w0 and wa combinations of DESI with CMB or with SNIa individually prefer w0gt1 and walt0. This preference is 2.6sigma for the DESICMB combination and persists or grows when SNIa are added in giving results discrepant with the LambdaCDM model at the 2.5sigma 3.5sigma or 3.9sigma levels for the addition of Pantheon Union3 or DESSN5YR datasets respectively. For the flat LambdaCDM model with the sum of neutrino mass sum mnu free combining the DESI and CMB data yields an upper limit sum mnu lt 0.072 0.113 eV at 95 confidence for a sum mnugt0 sum mnugt0.059 eV prior. These neutrinomass constraints are substantially relaxed in models beyond LambdaCDM. Abridged.

2024-04-01T00:00:00Z

['2024arXiv240403002D', '10.48550/arXiv.2404.03002', 'arXiv:2404.03002']

['Astrophysics - Cosmology and Nongalactic Astrophysics']

DESI 2024 VI Cosmological Constraints from the Measurements of Baryon Acoustic Oscillations

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https://arxiv.org/pdf/2404.03002.pdf

2024arXiv240907528E

To date galaxy image simulations for weak lensing surveys usually approximate the light profiles of all galaxies as a single or double Srsic profile neglecting the influence of galaxy substructures and morphologies deviating from such a simplified parametric characterization. While this approximation may be sufficient for previous data sets the stringent cosmic shear calibration requirements and the high quality of the data in the upcoming Euclid survey demand a consideration of the effects that realistic galaxy substructures have on shear measurement biases. Here we present a novel deep learningbased method to create such simulated galaxies directly from HST data. We first build and validate a convolutional neural network based on the wavelet scattering transform to learn noisefree representations independent of the pointspread function of HST galaxy images that can be injected into simulations of images from Euclids optical instrument VIS without introducing noise correlations during PSF convolution or shearing. Then we demonstrate the generation of new galaxy images by sampling from the model randomly and conditionally. Next we quantify the cosmic shear bias from complex galaxy shapes in Euclidlike simulations by comparing the shear measurement biases between a sample of model objects and their bestfit doubleSrsic counterparts. Using the KSB shape measurement algorithm we find a multiplicative bias difference between these branches with realistic morphologies and parametric profiles on the order of 6.9times 103 for a realistic magnitudeSrsic index distribution. Moreover we find clear detection bias differences between full image scenes simulated with parametric and realistic galaxies leading to a bias difference of 4.0times 103 independent of the shape measurement method. This makes it relevant for stage IV weak lensing surveys such as Euclid.

2024-09-01T00:00:00Z

['2024arXiv240907528E', '10.48550/arXiv.2409.07528', 'arXiv:2409.07528']

['Astrophysics - Cosmology and Nongalactic Astrophysics', 'Astrophysics - Astrophysics of Galaxies']

Euclid preparation. Deep learning true galaxy morphologies for weak lensing shear bias calibration

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https://arxiv.org/pdf/2409.07528.pdf

2024MNRAS.534.1634L

The gravitational wave GW signal from binary black hole BBH mergers is a promising probe of Population III Pop III stars. To fully unleash the power of the GW probe one important step is to understand the relative importance and features of different BBH evolution channels. We model two channels isolated binary stellar evolution IBSE and nuclear star clusterdynamical hardening NSCDH in one theoretical framework based on the semianalytical code ASLOTH under various assumptions on Pop III initial mass function IMF initial binary statistics and highz nuclear star clusters NSCs. The NSCDH channel contributes inlineformulatexmath idTM0002 notationLaTeXsim 895 rm per centtexmathinlineformula of Pop III BBH mergers across cosmic history with higher contributions achieved by initially wider binary stars more topheavy IMFs and more abundant highz NSCs. The dimensionless stochastic GW background SGWB produced by Pop III BBH mergers has peak values inlineformulatexmath idTM0004 notationLaTeXOmega rm peakrm GWsim 10118times 1011texmathinlineformula around observerframe frequencies inlineformulatexmath idTM0005 notationLaTeXnu sim 10100 rm Hztexmathinlineformula. The Pop III contribution can be a nonnegligible inlineformulatexmath idTM0006 notationLaTeXsim 232 rm per centtexmathinlineformula component in the total SGWB at inlineformulatexmath idTM0007 notationLaTeXnu lesssim 10 rm Hztexmathinlineformula. The estimated detection rates of Pop III BBH mergers by the Einstein Telescope are inlineformulatexmath idTM0008 notationLaTeXsim 6230texmathinlineformula and inlineformulatexmath idTM0009 notationLaTeXsim 301230 rm yr1texmathinlineformula for the NSCDH and IBSE channels respectively. Pop III BBH mergers in NSCs are more massive than those from IBSE so they dominate the Pop III SGWB below 20 Hz in most cases. Besides the detection rate of Pop III BBH mergers involving at least one intermediatemass BH above inlineformulatexmath idTM0010 notationLaTeX100 rm Modottexmathinlineformula by the Einstein Telescope is inlineformulatexmath idTM0011 notationLaTeXsim 0.5200 rm yr1texmathinlineformula in NSCs but remains below inlineformulatexmath idTM0012 notationLaTeX0.1 rm yr1texmathinlineformula for IBSE.

2024-11-01T00:00:00Z

['2024arXiv240617397L', 'arXiv:2406.17397', '2024MNRAS.tmp.2071L', '10.48550/arXiv.2406.17397', '10.1093/mnras/stae2120', '2024MNRAS.534.1634L']

['Astrophysics - Astrophysics of Galaxies', 'Astrophysics - High Energy Astrophysical Phenomena', 'Astrophysics - Solar and Stellar Astrophysics']

Gravitational waves from mergers of Population III binary black holes roles played by two evolution channels

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https://arxiv.org/pdf/2406.17397.pdf

2024arXiv240908873H

The prospect of phased laser arrays in space has received considerable attention in recent years with applications to both planetary defence and space exploration. The most detailed investigation conducted into such a design is that of the DESTAR phased array standing for textbfDirected textbfEnergy textbfSystems for textbfTargeting of textbfAsteroids and explotextbfRation. DESTAR is a square modular design which exploits the energy created by banks of solar cells in space to generate and amplify the power of a laser beam. A specific DESTAR design is expressed as DESTAR n where n typically in the range 0 4 equates to the log to base 10 of the side in metres of a square bank of lasers. With a DESTAR 4 structure 10 km times 10 km square capable of generating a laser beam on the order of tens of gigawatts clearly there is the potential for such an asset to be deployed as a weapon by targeting locations on Earth. This naturally leads to the question of what effective ways can this possible misuse be removed or at least mitigated to ensure these powerful space lasers can only be used for their intended purpose and never malevolent reasons. One solution would be to locate the DESTAR far enough away so that the laser flux at Earth would be too low. Results indicate that given they should lie 1 au from the Sun there are feasible locations for DESTAR 02 arrays where there is no danger to Earth. For DESTAR 45 such is their power safety measures other than those considered here would have to be adopted. Positions in the Solar System where the DESTAR lasers have no direct lineofsight with Earth tend to be unstable and would require regular corrections using an onboard propulsion system or preferably using pushback from the laser itself.

2024-09-01T00:00:00Z

['2024arXiv240908873H', '10.48550/arXiv.2409.08873', 'arXiv:2409.08873']

['Astrophysics - Earth and Planetary Astrophysics', 'Astrophysics - Instrumentation and Methods for Astrophysics']

Minimum Safe Distances for DESTAR Space Lasers

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https://arxiv.org/pdf/2409.08873.pdf

2024arXiv240907805I

The James Webb Space Telescope JWST has uncovered lowluminosity active galactic nuclei AGNs at high redshifts of zgtrsim 47 powered by accreting black holes BHs with masses of sim 1068Modot. These AGN populations are considered crucial for understanding early BH assembly and coevolution with their host galaxies. One remarkable distinction of these JWSTidentified AGNs compared to their lowredshift counterparts is that at least sim 20 of them present Halpha andor Hbeta absorption which must be associated with extremely dense gtrsim 109 cm3 gas along the line of sight. These Balmer absorption features unavoidably imply the presence of a Balmer break caused by the same dense gas. In this Letter we quantitatively demonstrate that a Balmerbreak feature can form in AGN spectra without stellar components when the accretion disk is heavily embedded in dense neutral gas clumps with densities of sim 10911 cm3 where hydrogen atoms are collisionally excited to the n2 states and effectively absorb the AGN continuum at the bluer side of the Balmer limit. The nonstellar origin of a Balmer break offers a potential solution to the large stellar masses and densities inferred for little red dots LRDs when assuming that their continuum is primarily due to stellar light. Our calculations of hydrogenlevel populations indicate that the observed Balmer absorption blueshifted by a few hundreds km s1 suggests the presence of dense outflows at parsec scales in the nucleus. The outflow rate likely exceeds the Eddington accretion rate driven by powerful radiation from a superEddington accretion disk. Other spectral features such as higher equivalent widths of broad Halpha emission and presence of OI lines observed in highredshift AGNs including LRDs align with the predicted signatures of a dense superEddington accretion disk.

2024-09-01T00:00:00Z

['arXiv:2409.07805', '10.48550/arXiv.2409.07805', '2024arXiv240907805I']

['Astrophysics - Astrophysics of Galaxies']

Extremely Dense Gas around Little Red Dots and Highredshift AGNs A Nonstellar Origin of the Balmer Break and Absorption Features

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https://arxiv.org/pdf/2409.07805.pdf

2024ApJ...975L..15L

The Schwarzschild radii of primordial black holes PBHs in the mass range of 6 10SUP14SUP4 10SUP19SUP g match the sizes of nuclei to atoms. I discuss the resulting quantummechanical suppression in the accretion of matter by PBHs in dense astrophysical environments such as planets or stars.

2024-11-01T00:00:00Z

['10.3847/2041-8213/ad887d', '10.48550/arXiv.2409.09081', 'arXiv:2409.09081', '2024arXiv240909081L', '2024ApJ...975L..15L']

['Black hole physics', 'Primordial black holes', '159', '1292', 'Astrophysics - High Energy Astrophysical Phenomena', 'General Relativity and Quantum Cosmology', 'High Energy Physics - Phenomenology']

Quantummechanical Suppression of Accretion by Primordial Black Holes

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https://arxiv.org/pdf/2409.09081.pdf

2024ApJ...974L...4P

We investigate the impact of nightside cloud formation on the observable daynight contrast of tidally locked terrestrial planet atmospheres. We demonstrate that in the case where the planetary dayside is only 10 s of Kelvin hotter than the planetary nightside the presence of optically thick nightside clouds can lead to observations that mimic a planet without an atmosphere despite the planet actually hosting a significant 10 bar atmosphere. The scenario presented in this work requires a level of intrinsic atmospheric daynight temperature contrast such that the nightside can form clouds while the dayside is too hot for cloud formation to occur. This scenario is most likely for hotter terrestrials and terrestrials with low volatile inventories. We thus note that a substantial daysidenightside temperature difference alone does not robustly indicate that a planet does not host an atmosphere and additional observations and modeling are essential for characterization. We further discuss several avenues for future study to improve our understanding of the terrestrial planets and how best to characterize them with JWST.

2024-10-01T00:00:00Z

['10.48550/arXiv.2409.07542', '2024arXiv240907542P', 'arXiv:2409.07542', '2024ApJ...974L...4P', '10.3847/2041-8213/ad78de']

['Exoplanet atmospheres', 'Atmospheric clouds', '487', '2180', 'Astrophysics - Earth and Planetary Astrophysics']

Nightside Clouds on Tidally Locked Terrestrial Planets Mimic Atmospherefree Scenarios

['EPRINT_HTML', 'EPRINT_PDF', 'PUB_HTML', 'PUB_PDF']

https://arxiv.org/pdf/2409.07542.pdf

2024ApJS..274...43S

We present an overview of Sherpa an opensource Python project and discuss its development history broad design concepts and capabilities. Sherpa contains powerful tools for combining parametric models into complex expressions that can be fit to data using a variety of statistics and optimization methods. It is easily extensible to include userdefined models statistics and optimization methods. It provides a highlevel user interface for interactive data analysis such as within a Jupyter notebook and it can also be used as a library component providing fitting and modeling capabilities to an application. We include a few examples of Sherpa applications to multiwavelength astronomical data.

2024-10-01T00:00:00Z

['arXiv:2409.10400', '2024ApJS..274...43S', '2024arXiv240910400S', '10.3847/1538-4365/ad7bab', '10.48550/arXiv.2409.10400']

['Astronomy software', '1855', 'Astrophysics - Instrumentation and Methods for Astrophysics', 'Astrophysics - High Energy Astrophysical Phenomena']

Sherpa An Opensource Python Fitting Package

['EPRINT_HTML', 'EPRINT_PDF', 'PUB_HTML', 'PUB_PDF']

https://arxiv.org/pdf/2409.10400.pdf

2024arXiv240908956D

Recent advancements in gravitational wave astronomy hold the promise of a completely new way to explore our Universe. These lecture notes aim to provide a concise but selfcontained introduction to key concepts of gravitational wave physics with a focus on the opportunities to explore fundamental physics in transient gravitational wave signals and stochastic gravitational wave background searches.CERNTH2024152

2024-09-01T00:00:00Z

['2024arXiv240908956D', 'arXiv:2409.08956', '10.48550/arXiv.2409.08956']

['Astrophysics - Cosmology and Nongalactic Astrophysics', 'General Relativity and Quantum Cosmology', 'High Energy Physics - Phenomenology']

Discovery Opportunities with Gravitational Waves TASI 2024 Lecture Notes

['EPRINT_HTML', 'EPRINT_PDF']

https://arxiv.org/pdf/2409.08956.pdf

2024PhRvD.110f3533T

Primordial black holes PBHs remain a viable dark matter candidate in the asteroidmass range. We point out that in this scenario the PBH abundance would be large enough for at least one object to cross through the inner Solar System per decade. Since Solar System ephemerides are modeled and measured to extremely high precision such close encounters could produce detectable perturbations to orbital trajectories with characteristic features. We evaluate this possibility with a suite of simple Solar System simulations and we argue that the abundance of asteroidmass PBHs can plausibly be probed by existing and nearfuture data.

2024-09-01T00:00:00Z

['10.48550/arXiv.2312.17217', 'arXiv:2312.17217', '10.1103/PhysRevD.110.063533', '2023arXiv231217217T', '2024PhRvD.110f3533T']

['Cosmology', 'Astrophysics - Cosmology and Nongalactic Astrophysics', 'Astrophysics - Earth and Planetary Astrophysics', 'High Energy Physics - Phenomenology']

Close encounters of the primordial kind A new observable for primordial black holes as dark matter

['EPRINT_HTML', 'EPRINT_PDF', 'PUB_HTML']

https://arxiv.org/pdf/2312.17217.pdf

2024JGRE..12908277E

The paper addresses the possibility of a young Mars having had a massive moon which synchronized the rotation of Mars and gave Mars an initial asymmetric triaxiality to be later boosted by geological processes. It turns out that a moon of less than a third of the lunar mass was capable of producing a sufficient initial triaxiality. The asymmetry of the initial tidal shape of the equator depends on timing the initial asymmetry is much stronger if the synchronous moon shows up already at the magmaocean stage. From the moment of synchronization of Mars rotation with the moons orbital motion and until the moon was eliminated as one possibility by an impact in the beginning of the Late Heavy Bombardment the moon was sustaining an early value of Mars rotation rate.

2024-10-01T00:00:00Z

['arXiv:2408.14725', '2024JGRE..12908277E', '10.48550/arXiv.2408.14725', '10.1029/2023JE008277', '2024arXiv240814725E']

['Mars', 'Tharsis', 'Syrtis Major Planum', 'bodily tides', 'body tides', 'land tides', 'Astrophysics - Earth and Planetary Astrophysics']

A Synchronous Moon as a Possible Cause of Mars Initial Triaxiality

['EPRINT_HTML', 'EPRINT_PDF', 'PUB_HTML']

https://arxiv.org/pdf/2408.14725.pdf

2024PSJ.....5..255G

Approximately one billion years Gyr in the future as the Sun brightens Earths carbonatesilicate cycle is expected to drive COSUB2SUB below the minimum level required by vascular land plants eliminating most macroscopic land life. Here we couple globalmean models of temperature and COSUB2SUBdependent plant productivity for CSUB3SUB and CSUB4SUB plants silicate weathering and climate to reexamine the time remaining for terrestrial plants. If weathering is weakly temperature dependent as recent data suggest andor strongly COSUB2 SUBdependent we find that the interplay between climate productivity and weathering causes the future luminositydriven COSUB2SUB decrease to slow and temporarily reverse averting plant COSUB2SUB starvation. This dramatically lengthens plant survival from 1 Gyr up to 1.61.86 Gyr until extreme temperatures halt photosynthesis suggesting a revised kill mechanism for land plants and potential doubling of the future lifespan of Earths land macrobiota. An increased future lifespan for the complex biosphere may imply that Earth life had to achieve a smaller number of hard steps unlikely evolutionary transitions to produce intelligent life than previously estimated. These results also suggest that complex photosynthetic land life on Earth and exoplanets may be able to persist until the onset of the moist greenhouse transition.

2024-11-01T00:00:00Z

['2024PSJ.....5..255G', '10.48550/arXiv.2409.10714', 'arXiv:2409.10714', '2024arXiv240910714G', '10.3847/PSJ/ad7856']

['Astrobiology', 'Habitable planets', 'Atmospheric evolution', 'Geological processes', '74', '695', '2301', '2289', 'Astrophysics - Earth and Planetary Astrophysics', 'Quantitative Biology - Populations and Evolution']

Substantial Extension of the Lifetime of the Terrestrial Biosphere

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https://arxiv.org/pdf/2409.10714.pdf

2024arXiv240906737B

Waste heat production represents an inevitable consequence of energy conversion as per the laws of thermodynamics. Based on this fact by using simple theoretical models we analyze constraints on the habitability of Earthlike terrestrial planets hosting putative technological species and technospheres characterized by persistent exponential growth of energy consumption and waste heat generation in particular we quantify the deleterious effects of rising surface temperature on biospheric processes and the eventual loss of liquid water. Irrespective of whether these sources of energy are ultimately stellar or planetary e.g. nuclear fossil fuels in nature we demonstrate that the loss of habitable conditions on such terrestrial planets may be expected to occur on timescales of lesssim 1000 years as measured from the start of the exponential phase provided that the annual growth rate of energy consumption is of order 1. We conclude by discussing the types of evolutionary trajectories that might be feasible for industrialized technological species and sketch the ensuing implications for technosignature searches.

2024-09-01T00:00:00Z

['2024arXiv240906737B', 'arXiv:2409.06737', '10.48550/arXiv.2409.06737']

['Astrophysics - Earth and Planetary Astrophysics', 'Astrophysics - Solar and Stellar Astrophysics', 'Physics - Applied Physics', 'Physics - Physics and Society', 'Physics - Space Physics']

Waste Heat and Habitability Constraints from Technological Energy Consumption

['EPRINT_HTML', 'EPRINT_PDF']

https://arxiv.org/pdf/2409.06737.pdf

2024arXiv240911447B

Soon after the release of the WISE allsky catalogue of 500 million midinfrared IR objects suggestions were made that it could be used to search for extrasolar devices constructed by an advanced civilization to convert a significant fraction of their host stars luminosity into useful work technostructures megastructures or Dyson spheresstructures hereafter DSMs whose inevitable waste heat would be seen by WISE at midIR wavelengths. However a trawl of several million potentiallyhabitable Gaiadetected stars for midIRexcess signatures is fraught with danger due to both noise from such a large sample and more importantly confusion with the emission from dusty background galaxies. In light of a recent claim of seven potential DSMs in MNRAS a brief rebuttal appeared on arXiv. Further to this response the relevance of WISEdetected galaxies is discussed in more detail leading to a seemingly tight limit on the number and lifetime of DSMs and indeed intelligent worlds in the 600pcradius region patrolled by Gaia. However the detectability of DSMs is questioned a DSM might extinguish its star at opticalnearIR wavelengths and thus either not appear or appear anomalously faint in a stellar catalogue. Moreover a civilization advanced enough to construct a DSM is likely to be advanced enough to use countermeasures to mask its presence from us.

2024-09-01T00:00:00Z

['arXiv:2409.11447', '10.48550/arXiv.2409.11447', '2024arXiv240911447B']

['Astrophysics - Instrumentation and Methods for Astrophysics', 'Physics - Popular Physics']

Did WISE detect Dyson SpheresStructures around Gaia2MASSselected stars

['EPRINT_HTML', 'EPRINT_PDF']

https://arxiv.org/pdf/2409.11447.pdf

2020A&A...641A...6P

We present cosmological parameter results from the final fullmission Planck measurements of the cosmic microwave background CMB anisotropies combining information from the temperature and polarization maps and the lensing reconstruction. Compared to the 2015 results improved measurements of largescale polarization allow the reionization optical depth to be measured with higher precision leading to significant gains in the precision of other correlated parameters. Improved modelling of the smallscale polarization leads to more robust constraints on many parameters with residual modelling uncertainties estimated to affect them only at the 0.5 level. We find good consistency with the standard spatiallyflat 6parameter CDM cosmology having a powerlaw spectrum of adiabatic scalar perturbations denoted base CDM in this paper from polarization temperature and lensing separately and in combination. A combined analysis gives dark matter density SUBcSUBhSUP2SUP 0.120 0.001 baryon density SUBbSUBhSUP2SUP 0.0224 0.0001 scalar spectral index nSUBsSUB 0.965 0.004 and optical depth 0.054 0.007 in this abstract we quote 68 confidence regions on measured parameters and 95 on upper limits. The angular acoustic scale is measured to 0.03 precision with 100SUBSUB 1.0411 0.0003. These results are only weakly dependent on the cosmological model and remain stable with somewhat increased errors in many commonly considered extensions. Assuming the baseCDM cosmology the inferred modeldependent lateUniverse parameters are Hubble constant HSUB0SUB 67.4 0.5 km sSUP1SUP MpcSUP1SUP matter density parameter SUBmSUB 0.315 0.007 and matter fluctuation amplitude SUB8SUB 0.811 0.006. We find no compelling evidence for extensions to the baseCDM model. Combining with baryon acoustic oscillation BAO measurements and considering singleparameter extensions we constrain the effective extra relativistic degrees of freedom to be NSUBeffSUB 2.99 0.17 in agreement with the Standard Model prediction NSUBeffSUB 3.046 and find that the neutrino mass is tightly constrained to mSUBSUB lt 0.12 eV. The CMB spectra continue to prefer higher lensing amplitudes than predicted in base CDM at over 2 which pulls some parameters that affect the lensing amplitude away from the CDM model however this is not supported by the lensing reconstruction or in models that also change the background geometry BAO data. The joint constraint with BAO measurements on spatial curvature is consistent with a flat universe SUBKSUB 0.001 0.002. Also combining with Type Ia supernovae SNe the darkenergy equation of state parameter is measured to be wSUB0SUB 1.03 0.03 consistent with a cosmological constant. We find no evidence for deviations from a purely powerlaw primordial spectrum and combining with data from BAO BICEP2 and Keck Array data we place a limit on the tensortoscalar ratio rSUB0.002SUB lt 0.06. Standard bigbang nucleosynthesis predictions for the helium and deuterium abundances for the baseCDM cosmology are in excellent agreement with observations. The Planck baseCDM results are in good agreement with BAO SNe and some galaxy lensing observations but in slight tension with the Dark Energy Surveys combinedprobe results including galaxy clustering which prefers lower fluctuation amplitudes or matter density parameters and in significant 3.6 tension with local measurements of the Hubble constant which prefer a higher value. Simple model extensions that can partially resolve these tensions are not favoured by the Planck data.

2020-09-01T00:00:00Z

['2018arXiv180706209P', '2020A&A...641A...6P', '10.48550/arXiv.1807.06209', '10.1051/0004-6361/201833910', 'arXiv:1807.06209']

['cosmic background radiation', 'cosmological parameters', 'Astrophysics - Cosmology and Nongalactic Astrophysics']

Planck 2018 results. VI. Cosmological parameters

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https://arxiv.org/pdf/1807.06209.pdf

2024Univ...10..396G

A pedagogical introduction to Bells inequality in Quantum Mechanics is presented. Several examples ranging from spin inlineformulammlmath idmm1mmlsemanticsmmlmrowmmlmn1mmlmnmmlmommlmommlmn2mmlmnmmlmrowmmlsemanticsmmlmathinlineformula to coherent and squeezed states are worked out. The generalization to Mermins inequalities and to GHZ states is also outlined.

2024-10-01T00:00:00Z

['10.48550/arXiv.2409.07597', '2024Univ...10..396G', 'arXiv:2409.07597', '10.3390/universe10100396', '2024arXiv240907597G']

['entanglement', "Bell's inequality", 'Quantum Physics', 'High Energy Physics - Theory', 'Mathematical Physics']

Introduction to Bells Inequality in Quantum Mechanics

['EPRINT_HTML', 'EPRINT_PDF', 'PUB_HTML']

https://arxiv.org/pdf/2409.07597.pdf

2024GeoRL..5110174M

Our solar systems path has recently been shown to potentially intersect dense interstellar clouds 2 and 7 million years ago the Local Lynx of Cold Cloud and the edge of the Local Bubble. These clouds compressed the heliosphere directly exposing Earth to the interstellar medium. Previous studies that examined climate effects of these encounters argued for an induced ice age due to the formation of global noctilucent clouds NLCs. Here we revisit such studies with a modern 2D atmospheric chemistry model using parameters of global heliospheric magnetohydrodynamic models as input. We show that NLCs remain confined to polar latitudes and short seasonal lifetimes during these dense cloud crossings lasting 10SUP5SUP years. Polar mesospheric ozone becomes significantly depleted but the total ozone column broadly increases. Furthermore we show that the densest NLCs lessen the amount of sunlight reaching the surface instantaneously by up to 7 while halving outgoing longwave radiation.

2024-09-01T00:00:00Z

['2024arXiv240906832M', '10.1029/2024GL110174', '2024GeoRL..5110174M', 'arXiv:2409.06832', '10.48550/arXiv.2409.06832']

['heliosphere', 'interstellar clouds', 'mesosphere', 'noctilucent clouds', 'ozone', 'paleoclimate', 'Astrophysics - Earth and Planetary Astrophysics', 'Astrophysics - Astrophysics of Galaxies', 'Physics - Atmospheric and Oceanic Physics']

Earths Mesosphere During Possible Encounters With Massive Interstellar Clouds 2 and 7 Million Years Ago

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https://arxiv.org/pdf/2409.06832.pdf

2024arXiv240904518T

If primordial black holes PBHs of asteroidal mass make up the entire dark matter they could be detectable through their gravitational influence in the solar system. In this work we study the perturbations that PBHs induce on the orbits of planets. Detailed numerical simulations of the solar system embedded in a halo of PBHs are performed. Using the EarthMars distance as an observational probe we show that the perturbations are below the current detection limits and thus PBHs are not directly constrained by solar system ephemerides. We estimate that an improvement in the measurement accuracy by more than an order of magnitude or the extraction of signals well below the noise level are required to detect the gravitational influence of PBHs in the solar system in the foreseeable future.

2024-09-01T00:00:00Z

['2024arXiv240904518T', '10.48550/arXiv.2409.04518', 'arXiv:2409.04518']

['Astrophysics - Earth and Planetary Astrophysics', 'General Relativity and Quantum Cosmology', 'High Energy Physics - Phenomenology']

Primordial Black Holes in the Solar System

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https://arxiv.org/pdf/2409.04518.pdf

2024AJ....168..283T

Planetplanet occultations PPOs occur when one exoplanet occults another exoplanet in the same system as seen from the Earths vantage point. PPOs may provide a unique opportunity to observe radio spillover from extraterrestrial intelligences radio transmissions or radar being transmitted from the farther exoplanet toward the nearer one for the purposes of communication or scientific exploration. Planetary systems with many tightly packed lowinclination planets such as TRAPPIST1 are predicted to have frequent PPOs. Here the narrowband technosignature search code turboSETI was used in combination with the newly developed NbeamAnalysis filtering pipeline to analyze 28 hr of beamformed data taken with the Allen Telescope Array during 2022 late October and early November from 0.9 to 9.3 GHz targeting TRAPPIST1. During this observing window seven possible PPO events were predicted using the NbodyGradient code. The filtering pipeline reduced the original list of 25 million candidate signals down to 6 million by rejecting signals that were not skylocalized and from these identified a final list of 11127 candidate signals above a powerlaw cutoff designed to segregate signals by their attenuation and morphological similarity between beams. All signals were plotted for visual inspection 2264 of which were found to occur during PPO windows. We report no detections of signals of nonhuman origin with upper limits calculated for each PPO event exceeding equivalent isotropic radiated powers of 2.1713.3 TW for minimally drifting signals and 40.8421 TW in the maximally drifting case. This work constitutes the longest singletarget radio search for extraterrestrial intelligence of TRAPPIST1 to date.

2024-12-01T00:00:00Z

['10.3847/1538-3881/ad823c', 'arXiv:2409.08313', '2024arXiv240908313T', '2024AJ....168..283T', '10.48550/arXiv.2409.08313']

['Radio astronomy', 'Search for extraterrestrial intelligence', 'Technosignatures', 'Radio interferometry', 'Astronomy software', 'Astrobiology', 'Exoplanet dynamics', '1338', '2127', '2128', '1346', '1855', '74', '490', 'Astrophysics - Earth and Planetary Astrophysics', 'Astrophysics - Instrumentation and Methods for Astrophysics']

A Radio Technosignature Search of TRAPPIST1 with the Allen Telescope Array

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https://arxiv.org/pdf/2409.08313.pdf

2024arXiv240910298C

Light pollution is a growing environmental issue that affects astronomy ecosystems human health. To address this we introduce the Free Dark Sky Meter FreeDSM an affordable IoTbased photometer designed for continuous light pollution monitoring. FreeDSM uses an ESP32 microcontroller with integrated sensors for light temperature and humidity and operates on an opensource platform. Data from multiple devices are centralized and processed using the Gambons model which leverages Gaia satellite data for accurate realtime assessments of natural light levels. This project is part of the Gaia4Sustainability initiative.

2024-09-01T00:00:00Z

['2024arXiv240910298C', '10.48550/arXiv.2409.10298', 'arXiv:2409.10298']

['Astrophysics - Instrumentation and Methods for Astrophysics']

FreeDSM and the Gaia4Sustaniability project a light pollution meter based on IoT technologies

['EPRINT_HTML', 'EPRINT_PDF']

https://arxiv.org/pdf/2409.10298.pdf

2024arXiv240912307N

The Earth sits inside a 300pcwide void that was carved by a series of supernova explosions that went off tens of millions of years ago pushing away interstellar gas and creating a bubblelike structure. The 60Fe peak deposits found in the deepsea crust have been interpreted by the imprints left by the ejecta of supernova explosions occurring about 23 and 56 Myr ago. It is likely that the 60Fe peak at about 23 Myr originated from a supernova occurring in the Upper Centaurus Lupus association in Scorpius Centaurus 140 pc or the Tucana Horologium association 70 pc. Whereas the 56 Myr peak is likely attributed to the solar systems entrance into the bubble. In this Letter we show that the supernova source responsible for synthesizing the 60Fe peak deposits 23 Myr ago was also likely a Galactic PeVatron source. We demonstrate that this supernova can consistently explain the knee in the cosmicray spectrum and the largescale anisotropy between 100 TeV and 100 PeV. Matching the intensity and shape of the cosmicray spectrum allows us to place stringent constraints on the cosmicray energy content from the supernova as well as on the cosmicray diffusion coefficient. Making use of such constraints we provide a robust estimate of the temporal variation of terrestrial ionizing cosmic radiation levels and discuss their implications in the development of early life on Earth by plausibly influencing the mutation rate and as such conceivably assisting in the evolution of complex organisms.

2024-09-01T00:00:00Z

['10.48550/arXiv.2409.12307', '2024arXiv240912307N', 'arXiv:2409.12307']

['Astrophysics - High Energy Astrophysical Phenomena', 'Astrophysics - Earth and Planetary Astrophysics']

Life in the Bubble How a nearby supernova left ephemeral footprints on the cosmicray spectrum and indelible imprints on life

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https://arxiv.org/pdf/2409.12307.pdf

2016cvpr.confE...1H

Deeper neural networks are more difficult to train. We present a residual learning framework to ease the training of networks that are substantially deeper than those used previously. We explicitly reformulate the layers as learning residual functions with reference to the layer inputs instead of learning unreferenced functions. We provide comprehensive empirical evidence showing that these residual networks are easier to optimize and can gain accuracy from considerably increased depth. On the ImageNet dataset we evaluate residual nets with a depth of up to 152 layers8x deeper than VGG nets but still having lower complexity. An ensemble of these residual nets achieves 3.57 error on the ImageNet test set. This result won the 1st place on the ILSVRC 2015 classification task. We also present analysis on CIFAR10 with 100 and 1000 layers. The depth of representations is of central importance for many visual recognition tasks. Solely due to our extremely deep representations we obtain a 28 relative improvement on the COCO object detection dataset. Deep residual nets are foundations of our submissions to ILSVRC amp COCO 2015 competitions where we also won the 1st places on the tasks of ImageNet detection ImageNet localization COCO detection and COCO segmentation.

2016-06-01T00:00:00Z

['10.48550/arXiv.1512.03385', 'arXiv:1512.03385', '2016cvpr.confE...1H', '10.1109/CVPR.2016.90', '2015arXiv151203385H']

['Computer Science - Computer Vision and Pattern Recognition']

Deep Residual Learning for Image Recognition

['EPRINT_HTML', 'EPRINT_PDF', 'PUB_HTML']

https://arxiv.org/pdf/1512.03385.pdf

2022zndo...6416330H

aqol6dmapuse Apply AQoL6D Utility Mapping Models To New Data. aqol6dmapuse is an R Markdown program. This release of the program updates the .lua filters to address an error in rendering the PDF version of the annotated program.

2022-03-01T00:30:00Z

['2022zndo...6416330H', '10.5281/zenodo.6416330']

aqol6dmapuse Apply AQoL6D Utility Mapping Models To New Data

['PUB_HTML']

2024arXiv241021980S

Robust modeling of nonlinear scales is critical for accurate cosmological inference in Stage IV surveys. For weak lensing analyses in particular a key challenge arises from the incomplete understanding of how nongravitational processes such as supernovae and active galactic nuclei collectively known as baryonic feedback affect the matter distribution. Several existing methods for modeling baryonic feedback treat it independently from the underlying cosmology an assumption which has been found to be inaccurate by hydrodynamical simulations. In this work we examine the impact of this coupling between baryonic feedback and cosmology on parameter inference at LSST Y1 precision. We build mock 3times2pt data vectors using the Magneticum suite of hydrodynamical simulations which span a wide range of cosmologies while keeping subgrid parameters fixed. We perform simulated likelihood analyses for two baryon mitigation techniques i the Principal Component Analysis PCA method which identifies eigenmodes for capturing the effect baryonic feedback on the data vector and ii HMCode2020 Mead et al. 2021 which analytically models the modification in the matter distribution using a halo model approach. Our results show that the PCA method is robust to the coupling between cosmology and baryonic feedback whereas when using HMCode2020 there can be up to 0.5sigma bias in OmegatextmS8. For HMCode2020 the bias also correlates with the input cosmology while for PCA we find no such correlation.

2024-10-01T00:00:00Z

['2024arXiv241021980S', 'arXiv:2410.21980']

['Astrophysics - Cosmology and Nongalactic Astrophysics']

Impact of cosmology dependence of baryonic feedback in weak lensing

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https://arxiv.org/pdf/2410.21980.pdf

2024arXiv241202562C

Many questions posed in the Astro2020 Decadal survey in both the New Messengers and New Physics and the Cosmic Ecosystems science themes require a gammaray mission with capabilities exceeding those of existing e.g. Fermi Swift and planned e.g. COSI observatories. ComPair the Compton Pair telescope is a prototype of such a nextgeneration gammaray mission. It had its inaugural balloon flight from Ft. Sumner New Mexico in August 2023. To continue the goals of the ComPair project to develop technologies that will enable a future gammaray mission the next generation of ComPair ComPair2 will be upgraded to increase the sensitivity and lowenergy transient capabilities of the instrument. These advancements are enabled by AstroPix a silicon monolithic active pixel sensor in the tracker and custom dualgain silicon photomultipliers and frontend electronics in the calorimeter. This effort builds on design work for the Allsky Medium Energy Gammaray Observatory eXplorer AMEGOX concept that was submitted the 2021 MIDEX Announcement of Opportunity. Here we describe the ComPair2 prototype design and integration and testing plans to advance the readiness level of these novel technologies.

2024-12-01T00:00:00Z

['2024arXiv241202562C', 'arXiv:2412.02562']

['Astrophysics - Instrumentation and Methods for Astrophysics', 'Astrophysics - High Energy Astrophysical Phenomena']

ComPair2 A Next Generation Medium Energy Gammaray Telescope Prototype

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https://arxiv.org/pdf/2412.02562.pdf

2024arXiv241202378F

The possibility of an atomic detection of gravitational waves on earth is considered. The combination of extremely high lifetimes and resulting small radiative transition probabilities with rapidly growing interaction strength for Rydberg atoms having principal quantum numbers in a region 104ldots 105 might result in transition probabilities which are high enough to open up such a possibility. Transition probabilities and absorption cross sections are calculated as a function of the relevant quantum numbers of a highly excited electron. The orders of magnitude for the transition rate are evaluated for a realistic source of gravitational radiation. It is shown that no specific particle property enters the expression for the absorption cross section for gravitational waves. The only fundamental constant contained in this cross section is apart from the fine structure constant alpha the Planck length Lhbar G c312.

2024-12-01T00:00:00Z

['2024arXiv241202378F', 'arXiv:2412.02378']

['Quantum Physics', 'General Relativity and Quantum Cosmology']

Transition probabilities for a Rydberg atom in the field of a gravitational wave

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https://arxiv.org/pdf/2412.02378.pdf

2024arXiv241206830T

The 20232032 Planetary Science and Astrobiology Decadal Survey Origins Worlds and Life recommended that NASA develop scientific exploration strategies as it has for Mars in areas of broad scientific importance e.g. Venus... that have an increasing number of U.S. missions and international collaboration opportunities OWL p.2210. In NASAs initial responses to that Decadal Survey the agency asserted that ...specific scientific exploration strategies should be community generated by bodies such as the Analysis Groups thus placing the onus on the planetary community to generate and support these exploration strategies. In late 2022 the Venus Exploration Analysis Group began a project to develop a new exploration strategy for Venus reflecting the 2021 selections of the VERITAS DAVINCI and EnVision missions and the sweeping comparative planetology recommendations relevant to Venus in Origins Worlds and Life. This is that strategy. Taking a broad look at the scientific technological and programmatic advances required to address the key outstanding questions that Venus poses and predicated on VERITAS DAVINCI and EnVision flying as planned in the early 2030s this report outlines a set of actions available to NASA VEXAG and the planetary science community at large to establish a sustained program of Venus exploration in the years and decades ahead. Key to this approach is recognizing Venus as a unique setting where multiple crossdisciplinary Decadallevel planetary Earth heliophysics and exoplanet science questions can be addressed as well as being a worthy target of exploration in its own right. This report offers Assessments of the current state of Venus exploration and Actions for the U.S. and international Venus community as well as NASA to consider. This strategy is a living document and should be updated as warranted.

2024-12-01T00:00:00Z

['arXiv:2412.06830', '2024arXiv241206830T']

['Astrophysics - Instrumentation and Methods for Astrophysics', 'Astrophysics - Earth and Planetary Astrophysics']

A New Strategy for the Exploration of Venus

['EPRINT_HTML', 'EPRINT_PDF']

https://arxiv.org/pdf/2412.06830.pdf

2024arXiv241113434D

The evolution of a deformed subcritical fast magnetosonic shock front is compared between two twodimensional PIC simulations with different orientations of the magnetic field relative to the simulation box. All other initial and simulation conditions are kept identical. Shock boundary oscillations are observed in the simulation where the magnetic field direction is resolved. This oscillation is caused by the reformation of the shock front. One part of the front acts as a shock while the other functions as a magnetic piston with both halves changing their states in antiphase. The oscillation period corresponds to the time required for one shock wave to grow as the other collapses. In contrast the corrugated fast magnetosonic shock does not oscillate in the second simulation where the magnetic field is oriented out of the simulation plane. This dependence on magnetic field orientation suggests that the shock oscillation is induced by magnetic tension which is only effective in the first simulation. In both simulations the shock perturbation does not grow over time indicating that the shocks are stable. The potential relevance of these findings for the Alfvenic oscillations of the supercritical Earths bow shock detected by the MMS multispacecraft mission is also discussed.

2024-11-01T00:00:00Z

['2024arXiv241113434D', 'arXiv:2411.13434']

['Physics - Plasma Physics', 'Astrophysics - High Energy Astrophysical Phenomena']

Oscillations of subcritical fast magnetosonic shock boundaries caused by shock reformation

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https://arxiv.org/pdf/2411.13434.pdf

2024arXiv241117047R

Extragalactic Black Hole Xray Binaries BHXRBs are the most intriguing Xray sources as some of them are home to the most massive stellarmass BHs ever found. In this work we conduct a comprehensive study of three massive eclipsing extragalactic BHXRBs i.e. M33X7 NGC300X1 and IC10X1 and using entire Xray observations available from textitXMMNewton and textitNuSTAR till date. Preliminary analysis using textitdiskbb and textitpowerlaw models shows that the sources have steep spectra and subEddington luminosities L0.69 LEdd with major flux contribution from nonthermal component resembling the relatively uncharted Steep Powerlaw State SPL. To understand the accretion disc properties in this state we explore alternate modelling scenario that reveals the presence of a hot kTin12 keV slimdisc textitdiskpbb with radial temperature profile Trpropto rp p0.50.66 along with a cooler kTin0.10.2 keV standard thermal disc textitdiskbb. We carry out the continuumfitting method using relativistic slimdisc model textitslimbh and estimate the mass range of M33 X7 NGC300X1 and IC10X1 is to be 915 Modot 928 Modot and 1030 Modot respectively. Further eclipse periods are determined by modelling the lightcurve using which we estimate the size of the eclipsing bodies. Modelling of the eclipse spectra revealed the complete obscuration of soft spectral component during eclipse implying the emission of hard component from an extended accretion region. Based on our findings we provide an inference on geometry of accretion disc in these windfed systems and compare their properties with the other two extragalactic BHXRBs.

2024-11-01T00:00:00Z

['arXiv:2411.17047', '2024arXiv241117047R']

['Astrophysics - High Energy Astrophysical Phenomena']

Accretion disc dynamics in extragalactic black hole Xray binaries A comprehensive study of M33 X7 NGC 300 X1 and IC 10 X1

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https://arxiv.org/pdf/2411.17047.pdf

2024arXiv241201921O

Significant mass loss in the red supergiant RSG phase has great influence on the evolution of massive stars and their final fate as supernovae. We present nearinfrared interferometric imaging of the circumstellar environment of the dustenshrouded RSG WOH G64 in the Large Magellanic Cloud. WOH G64 was observed with the GRAVITY instrument at ESOs Very Large Telescope Interferometer VLTI at 2.02.45 micron. We succeeded in imaging the innermost circumstellar environment of WOH G64 the first interferometric imaging of an RSG outside the Milky Way. The reconstructed image reveals elongated compact emission with a semimajor and semiminor axis of 2 and 1.5 mas 13 and 9 stellar radii respectively. The GRAVITY data show that the stellar flux contribution at 2.2 micron at the time of our observations in 2020 is much lower than predicted by the optically and geometrically thick dust torus model based on the VLTIMIDI data taken in 2005 and 2007. We found a significant change in the nearinfrared spectrum of WOH G64 while the spectrophotometric data taken at 12.5 micron before 2003 show the spectrum of the central RSG with H2O absorption the spectra and JHK photometric data taken after 2016 are characterized by a monotonically rising continuum with very weak signatures of H2O. This spectral change likely took place between December 2009 and 2016. On the other hand the midinfrared spectrum obtained in 2022 with VLTVISIR agrees well with the spectra obtained before 2007. The compact emission imaged with GRAVITY and the nearinfrared spectral change suggest the formation of hot new dust close to the star which gives rise to the monotonically rising nearinfrared continuum and the high obscuration of the central star. The elongation of the emission may be due to the presence of a bipolar outflow or effects of an unseen companion.

2024-12-01T00:00:00Z

['2024arXiv241201921O', 'arXiv:2412.01921']

['Astrophysics - Solar and Stellar Astrophysics', 'Astrophysics - Astrophysics of Galaxies']

Imaging the innermost circumstellar environment of the red supergiant WOH G64 in the Large Magellanic Cloud

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https://arxiv.org/pdf/2412.01921.pdf

2024arXiv241201873D

In the postNewtonian era the Eddingtoninspired BornInfeld EiBI theory considered as an improved modification of the Einsteinian general relativity formalism in the weak field regime nonrelativistic has enabled us to study the dynamics of dense astroobjects in light of the modified gravitational effects. This EiBI theory imparts a new shape to the usual gravitational Poisson equation through the addition of a cosmological correction factor termed as the EiBI gravity parameter. A systematic inclusion of this gravity in the basic structure equation could lead to a realistic picture of the existing solar models free from any endstage singularity. A theoretic model is accordingly proposed to investigate the effect of the EiBI gravity on the GravitoElectrostatic Sheath GES formalism of the equilibrium solar plasma structure. This study shows that the GESbased solar plasma dynamics is noticeably modified against the previously reported Newtonian GESmodel studies. An equilibrium bounded solution for the solar selfgravity shows the EiBImodified solar surface boundary SSB to exist at a new heliocentric radial location xi 4 on the Jeansean scale. It is found that the EiBI gravity shifts the present SSB outwards by 14.28 relative to the original Newtonian SSB. The EiBImodified gravity effects on diverse relevant solar parameters such as the gravitoelectrostatic potentials fields and Mach numbers are illustratively analyzed. It is anticipated that our analyses could be applied further to see the solar plasma equilibrium and fluctuation dynamics in realistically modified postNewtonian gravity environments on both the bounded interior and unbounded exterior solar plasma scales.

2024-12-01T00:00:00Z

['arXiv:2412.01873', '2024arXiv241201873D']

['General Relativity and Quantum Cosmology', 'Astrophysics - Solar and Stellar Astrophysics', 'Physics - Plasma Physics', 'Physics - Space Physics']

Solar GESstructure modified with EiBI gravity

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https://arxiv.org/pdf/2412.01873.pdf

2016zndo....555999A

Implements selected inverse reinforcement learning IRL algorithms as part of COMP3710 at the Australian National University Linear programming IRL. From Ng Russell 2000. Small state space and large state space linear programming IRL. Maximum entropy IRL. From Ziebart et al. 2008. Deep maximum entropy IRL. From Wulfmeier et al. 2015 original derivation. Additionally the following MDP domains are implemented Gridworld Sutton 1998 Objectworld Levine et al. 2011

2016-03-24T00:30:00Z

['2016zndo....555999A', '10.5281/zenodo.555999']

['inverse reinforcement learning', 'reinforcement learning', 'ai']

Inverse Reinforcement Learning

['PUB_HTML']

2024arXiv241201925I

Binary black hole BBH evolution in the discs of active galactic nuclei AGN is a promising channel for gravitational wave GWdriven mergers. It is however unclear whether binaries interacting with the surrounding disc undergo orbital contraction or expansion. We develop a simple analytic model of accreting BBHs in AGN discs to follow the orbital evolution from the discdominated regime at large separations into the GWdriven regime at small separations the coupled discGWdriven evolution. We obtain that accreting binaries expand in thick discs with aspect ratio greater than a critical value hmathrmcrit whereas accreting binaries contract and eventually merge in thin discs hmathrmcrit. Interestingly accreting BBHs can experience faster mergers compared to nonaccreting counterparts with a nonmonotonic dependence on the disc aspect ratio. The orbital contraction is usually coupled with eccentricity growth in the discdominated regime which lead to accelerated inspirals in the GWdriven regime. We quantify the resulting BBH merger timescales in AGN discs taumathrmmerger sim 105 107 yr and estimate the associated GW merger rates mathcalR sim 0.2 5 textGpc3 textyr1. Overall accreting binaries may efficiently contract and merge in thin discs hence this particular BBHinAGN channel may provide a nonnegligible contribution to the observed GW merger event rate.

2024-12-01T00:00:00Z

['2024arXiv241201925I', 'arXiv:2412.01925']

['Astrophysics - High Energy Astrophysical Phenomena', 'Astrophysics - Astrophysics of Galaxies']

Gravitational wave mergers of accreting binary black holes in AGN discs

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https://arxiv.org/pdf/2412.01925.pdf

2024arXiv241202112C

The Legacy Survey of Space and Time to be conducted with the Vera C. Rubin Observatory is poised to revolutionize our understanding of the Solar System by providing an unprecedented wealth of data on various objects including the elusive interstellar objects ISOs. Detecting and classifying ISOs is crucial for studying the composition and diversity of materials from other planetary systems. However the rarity and brief observation windows of ISOs coupled with the vast quantities of data to be generated by LSST create significant challenges for their identification and classification. This study aims to address these challenges by exploring the application of machine learning algorithms to the automated classification of ISO tracklets in simulated LSST data. We employed various machine learning algorithms including random forests RFs stochastic gradient descent SGD gradient boosting machines GBMs and neural networks NNs to classify ISO tracklets in simulated LSST data. We demonstrate that GBM and RF algorithms outperform SGD and NN algorithms in accurately distinguishing ISOs from other Solar System objects. RF analysis shows that many derived Digest2 values are more important than direct observables in classifying ISOs from the LSST tracklets. The GBM model achieves the highest precision recall and F1 score with values of 0.9987 0.9986 and 0.9987 respectively. These findings lay the foundation for the development of an efficient and robust automated system for ISO discovery using LSST data paving the way for a deeper understanding of the materials and processes that shape planetary systems beyond our own. The integration of our proposed machine learning approach into the LSST data processing pipeline will optimize the surveys potential for identifying these rare and valuable objects enabling timely followup observations and further characterization.

2024-12-01T00:00:00Z

['2024arXiv241202112C', 'arXiv:2412.02112']

['Astrophysics - Earth and Planetary Astrophysics', 'Astrophysics - Astrophysics of Galaxies', 'Astrophysics - Instrumentation and Methods for Astrophysics', 'Computer Science - Machine Learning']

Machine Learning Methods for Automated Interstellar Object Classification with LSST

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https://arxiv.org/pdf/2412.02112.pdf