cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
On the Running of Gauge Couplings in String Theory
Creators: name: Abel, Steven
name: Dienes, Keith R.
name: Nutricati, Luca A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In this paper we conduct a general, model-independent analysis of the running of gauge couplings within closed string theories. Unlike previous discussions in the literature, our calculations fully respect the underlying modular invariance of the string and include the contributions from the infinite towers of string states which are ultimately responsible for many of the properties for which string theory is famous, including an enhanced degree of finiteness and UV/IR mixing. In order to perform our calculations, we adopt a formalism that was recently developed for calculations of the Higgs mass within such theories, and demonstrate that this formalism can also be applied to calculations of gauge couplings. In general, this formalism gives rise to an ``on-shell'' effective field theory (EFT) description in which the final results are expressed in terms of supertraces over the physical string states, and in which these quantities exhibit an EFT-like ``running'' as a function of an effective spacetime mass scale. We find, however, that the calculation of the gauge couplings differs in one deep way from that of the Higgs mass: while the latter results depend on purely on-shell supertraces, the former results have a different modular structure which causes them to depend on off-shell supertraces as well. In some regions of parameter space, our results demonstrate how certain expected field-theoretic behaviors can emerge from the highly UV/IR-mixed environment. In other situations, by contrast, our results give rise to a number of intrinsically stringy behaviors that transcend what might be expected within an effective field theory approach.
description: 37 pages, LaTeX, 5 figures
Detection of Possible Quasi-periodic Oscillations in the Long-term Optical Light Curve of the BL Lac Object OJ 287
Creators: name: Bhatta, G.
name: Zola, S.
name: Stawarz, Ł.
name: Ostrowski, M.
name: Winiarski, M.
name: Ogłoza, W.
name: Dróżdz, M.
name: Siwak, M.
name: Liakos, A.
name: Kozieł-Wierzbowska, D.
name: Gazeas, K.
name: Debski, B.
name: Kundera, T.
name: Stachowski, G.
name: Paliya, V. S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Detection of periodicity in the broad-band non-thermal emission of blazars has so far been proven to be elusive. However, there are a number of scenarios which could lead to quasi-periodic variations in blazar light curves. For example, orbital or thermal/viscous period of accreting matter around central supermassive black holes could, in principle, be imprinted in the multi-wavelength emission of small-scale blazar jets, carrying as such crucial information about plasma conditions within the jet launching regions. In this paper, we present the results of our time series analysis of $\sim 9.2$ year-long, and exceptionally well-sampled optical light curve of the BL Lac OJ 287. The study primarily uses the data from our own observations performed at the Mt. Suhora and Kraków Observatories in Poland, and at the Athens Observatory in Greece. Additionally, SMARTS observations were used to fill in some of the gaps in the data. The Lomb-Scargle Periodogram and the Weighted Wavelet Z-transform methods were employed to search for the possible QPOs in the resulting optical light curve of the source. Both the methods consistently yielded possible quasi-periodic signal around the periods of $\sim 400$ and $\sim 800$ days, the former one with a significance (over the underlying colored noise) of $\geq 99\%$. A number of likely explanations for such are discussed, with a preference given to a modulation of the jet production efficiency by highly magnetized accretion disks. This supports the previous findings and the interpretation reported recently in the literature for OJ 287 and other blazar sources.
description: 7 pages, 5 figures, ApJ accepted
Ultraviolet Halos Around Spiral Galaxies. I. Morphology
Creators: name: Hodges-Kluck, Edmund
name: Cafmeyer, Julian
name: Bregman, Joel
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We examine ultraviolet halos around a sample of highly inclined galaxies within 25 Mpc to measure their morphology and luminosity. Despite contamination from galactic light scattered into the wings of the point-spread function, we find that UV halos occur around each galaxy in our sample. Around most galaxies the halos form a thick, diffuse disk-like structure, but starburst galaxies with galactic superwinds have qualitatively different halos that are more extensive and have filamentary structure. The spatial coincidence of the UV halos above star-forming regions, the lack of consistent association with outflows or extraplanar ionized gas, and the strong correlation between the halo and galaxy UV luminosity suggest that the UV light is an extragalactic reflection nebula. UV halos may thus represent 1-10 million solar masses of dust within 2-10 kpc of the disk, whose properties may change with height in starburst galaxies.
description: 29 pages, 10 tables, 12 figures, accepted to ApJ
Towards a Versatile Terminology Service for Empowering FAIR Research Data: Enabling Ontology Discovery, Design, Curation, and Utilization Across Scientific Communities
Creators: name: Strömert, Philip
name: Limbachia, Vatsal
name: Oladazimi, Pooya
name: Hunold, Johannes
name: Koepler, Oliver
Publisher: name: Zenodo
Year: 2023
Subjects: Terminology Services, OLS, Ontology Curation, Ontology, Ontology Harmonization, FAIR Research Data Management, RDM, FAIR

description: Presentation of the paper at SEMANTiCS 2023 (https://2023-eu.semantics.cc/) --- Funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under the National Research Data Infrastructure – NFDI4Chem – Projektnummer 441958208
Spin evolution of Venus-like planets subjected to gravitational and thermal tides
Creators: name: Revol, Alexandre
name: Bolmont, Émeline
name: Tobie, Gabriel
name: Dumoulin, Caroline
name: Musseau, Yann
name: Mathis, Stéphane
name: Strugarek, Antoine
name: Brun, Allan-Sacha
Publisher: name: arXiv
Year: 2023
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The arrival of powerful instruments will provide valuable data for the characterization of rocky exoplanets. It is then crucial to accurately model the dynamical state of exoplanets. Rocky planets with sufficiently large orbits should have non-zero eccentricities and/or obliquities. Realistic models of tides for rocky planets can allow for higher spin states than the synchronization state in the presence of eccentricities or obliquities. This work explores the secular evolution of a star-planet system under tidal interactions, both gravitational and thermal, induced respectively by the quadrupolar component of the gravitational potential and the irradiation of the planet's surface. We use the formalism of Kaula associated with an Andrade rheology to model a relevant response of a rocky planet to gravitational tides and a prescription of thermal tides fitted for Venus to model the response of the atmosphere to the thermal tides. We implemented the general secular evolution equations of tidal interactions in the secular code ESPEM (French acronym for Evolution of Planetary System and Magnetism). We show the possible spin-orbit evolution and resonances for eccentric orbits and explore the possible spin orbit resonances raised by the obliquity of the planet. Our simulations have shown that the secular evolution of the spin and obliquity can lead to the retrograde spin of the Venus-like planet if the system starts from a high spin obliquity, in agreement to previous studies. Taking into account the luminosity evolution of the Sun changes the picture. We find that the planet never reaches the equilibrium: the timescale of rotation evolution is longer than the luminosity variation timescale, which suggests that Venus may never reach a spin equilibrium state but may still evolve.
description: 19 pages, 16 figues
Anisotropic transport of normal metal-barrier-normal metal junctions in monolayer phosphorene
Creators: name: De Sarkar, Sangita
name: Agarwal, Amit
name: Sengupta, K.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We study transport properties of a phosphorene monolayer in the presence of single and multiple potential barriers of height $U_0$ and width $d$, using both continuum and microscopic lattice models, and show that the nature of electron transport along its armchair edge ($x$ direction) is qualitatively different from its counterpart in both conventional two-dimensional electron gas with Schrödinger-like quasiparticles and graphene or surfaces of topological insulators hosting massless Dirac quasiparticles. We show that the transport, mediated by massive Dirac electrons, allows one to achieve collimated quasiparticle motion along $x$ and thus makes monolayer phosphorene an ideal experimental platform for studying Klein paradox. We study the dependence of the tunneling conductance $G \equiv G_{xx}$ as a function of $d$ and $U_0$, and demonstrate that for a given applied voltage $V$ its behavior changes from oscillatory to decaying function of $d$ for a range of $U_0$ with finite non-zero upper and lower bounds, and provide analytical expression for these bounds within which $G$ decays with $d$. We contrast such behavior of $G$ with that of massless Dirac electrons in graphene and also with that along the zigzag edge ($y$ direction) in phosphorene where the quasiparticles obey an effective Schrödinger equation at low energy. We also study transport through multiple barriers along $x$ and demonstrate that these properties hold for transport through multiple barrier as well. Finally, we suggest concrete experiments which may verify our theoretical predictions.
description: v1; 11+ pages, 12 figs
Two types of phase diagrams for two-species Bose-Einstein condensates
Creators: name: Li, Z. B.
name: Liu, Y. M.
name: Yao, D. X.
name: Bao, C. G.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: Under the Thomas-Fermi approximation, a relatively much simpler analytical solutions of the coupled Gross-Pitaevskii equations for the two-species BEC have been derived. Additionally, a model for the asymmetric states has been proposed, and the competition between the symmetric and asymmetric states has been evaluated. The whole parameter-space is divided into zones, each supports a specific phase, namely, the symmetric miscible phase, the symmetric immiscible phase, or the asymmetric phase. Based on the division the phase-diagrams against any set of parameters can be plotted. Thereby, the effects of these parameters can be visualized. There are three critical values in the inter-species interaction $% V_{AB} $ and one in the ratio of particle numbers $N_{A}/N_{B}$. They govern the transitions between the phases. Two cases, (i) the repulsive $V_{AB}$ matches the repulsive $% V_{A}+V_{B}$, and (ii) the attractive $V_{AB}$ nearly cancels the effect of the repulsive $V_{A}+V_{B}$ have been particularly taken into account. The former leads to a complete separation of the two kinds of atoms , while the latter lead to a collapse. Finally, based on an equation derived in the paper, a convenient experimental approach is proposed to determine the ratio of particle numbers .
description: 8 pages, 5 figures
TESS Experiments: The Wages of Parenthood: At the Intersection of Sexual Orientation and Child Caregiving
Creators: name: Demerjian, Sascha
Publisher: name: Roper Center for Public Opinion Research
Year: 2022

description: Time-sharing Experiments for the Social Sciences (TESS) offers researchers the opportunity to capture the internal validity of experiments. Investigators submit proposals, and TESS fields successful proposals for free on a representative sample of adults in the United States. This experiment was conducted to explore the aspects of job attainment, advancement, and salary penalties for working parents. Respondents were randomly assigned to evaluate one of twelve fictitious job candidates each of whom were married with two children. Job candidates varied by gender (male or female), sexual orientation (heterosexual or homosexual) and parenting role (not indicated, secondary caregiver, or primary caregiver). A total of 1,013 respondents participated. After reading the candidate’s profile, respondents answered whether they considered the candidate competent, committed, and organized, the likelihood that they would interview and hire the candidate, whether the candidate would be suitable for promotion, and what salary they would start the candidate off at. This allowed for comparison of assumptions about job candidates with differing childcare responsibilities across gender and sexual orientation.
A Multifidelity deep operator network approach to closure for multiscale systems
Creators: name: Ahmed, Shady E.
name: Stinis, Panos
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Machine Learning (cs.LG)
subject: Numerical Analysis (math.NA)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Projection-based reduced order models (PROMs) have shown promise in representing the behavior of multiscale systems using a small set of generalized (or latent) variables. Despite their success, PROMs can be susceptible to inaccuracies, even instabilities, due to the improper accounting of the interaction between the resolved and unresolved scales of the multiscale system (known as the closure problem). In the current work, we interpret closure as a multifidelity problem and use a multifidelity deep operator network (DeepONet) framework to address it. In addition, to enhance the stability and accuracy of the multifidelity-based closure, we employ the recently developed "in-the-loop" training approach from the literature on coupling physics and machine learning models. The resulting approach is tested on shock advection for the one-dimensional viscous Burgers equation and vortex merging using the two-dimensional Navier-Stokes equations. The numerical experiments show significant improvement of the predictive ability of the closure-corrected PROM over the un-corrected one both in the interpolative and the extrapolative regimes.
description: 24 pages, 21 figures
Atmospheres as windows into sub-Neptune interiors: coupled chemistry and structure of hydrogen-silane-water envelopes
Creators: name: Misener, William
name: Schlichting, Hilke E.
name: Young, Edward D.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Sub-Neptune exoplanets are commonly hypothesized to consist of a silicate-rich magma ocean topped by a hydrogen-rich atmosphere. Previous work studying the outgassing of silicate material has demonstrated that such atmosphere-interior interactions can affect the atmosphere's overall structure and extent. But these models only considered SiO in an atmosphere of hydrogen gas, without considering chemical reactions between them. Here we couple calculations of the chemical equilibrium between H, Si, and O species with an atmospheric structure model. We find that substantial amounts of silane, SiH$_4$, and water, H$_2$O, are produced by the interaction between the silicate-rich interior and hydrogen-rich atmosphere. These species extend high into the atmosphere, though their abundance is greatest at the hottest, deepest regions. For example, for a 4 $M_\oplus$ planet with an equilibrium temperature of 1000 K, a base temperature of 5000 K, and a 0.1 $M_\oplus$ hydrogen envelope, silicon species and water can comprise 30 percent of the atmosphere by number at the bottom of the atmosphere. Due to this abundance enhancement, we find that convection is inhibited at temperatures $\gtrsim 2500$ K. This temperature is lower, implying that the resultant non-convective region is thicker, than was found in previous models which did not account for atmospheric chemistry. Our findings show that significant endogenous water is produced by magma-hydrogen interactions alone, without the need to accrete ice-rich material. We discuss the observability of the signatures of atmosphere-interior interaction and directions for future work, including condensate lofting and more complex chemical networks.
description: 13 pages, 12 figures, accepted for publication in MNRAS
Carbon-Oxygen Phase Separation in MESA White Dwarf Models
Creators: name: Bauer, Evan B.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We enhance the treatment of crystallization for models of white dwarfs (WDs) in the stellar evolution software MESA by implementing carbon-oxygen (C/O) phase separation. The phase separation process during crystallization leads to transport of oxygen toward the center of WDs, resulting in a more compact structure that liberates gravitational energy as additional heating that modestly slows WD cooling timescales. We quantify this cooling delay in MESA C/O WD models over the mass range 0.5-1.0 $M_\odot$, finding delays of 0.5-0.8 Gyr for typical C/O interior profiles. MESA WD cooling timescales including this effect are generally comparable to other WD evolution models that make similar assumptions about input physics. When considering phase separation alongside $^{22}$Ne sedimentation, however, we find that both MESA and BaSTI WD cooling models predict a more modest sedimentation delay than the latest LPCODE models, and this may therefore require a re-evaluation of previously proposed solutions to some WD cooling anomalies that were based on LPCODE models of $^{22}$Ne sedimentation. Our implementation of C/O phase separation in the open-source stellar evolution software MESA provides an important tool for building realistic grids of WD cooling models, as well as a framework for expanding on our implementation to explore additional physical processes related to phase transitions and associated fluid motions in WD interiors.
description: 15 pages, 9 figures, accepted for publication in ApJ
High refractive index Fresnel lens on a fiber fabricated by nanoimprint lithography for immersion applications
Creators: name: Koshelev, Alexander
name: Calafiore, Giuseppe
name: Piña-Hernandez, Carlos
name: Allen, Frances
name: Dhuey, Scott
name: Sassolini, Simone
name: Wong, Edward
name: Lum, Paul
name: Munechika, Keiko
name: Cabrini, Stefano
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: In this Letter we present a Fresnel lens fabricated on the end of an optical fiber. The lens is fabricated using nanoimprint lithography of a functional high refractive index material, which is suitable for mass production. The main advantage of the presented Fresnel lens compared to a conventional fiber lens is its high refractive index (n=1.69), which enables efficient light focusing even inside other media such as water or adhesive. Measurement of the lens performance in an immersion liquid (n=1.51) shows a near diffraction limited focal spot of 810 nm in diameter at the 1/e2 intensity level for a wavelength of 660 nm. Applications of such fiber lenses include integrated optics, optical trapping and fiber probes.
description: 4 pages , 5 figures
Model-independent bubble wall velocities in local thermal equilibrium
Creators: name: Ai, Wen-Yuan
name: Laurent, Benoit
name: van de Vis, Jorinde
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Accurately determining bubble wall velocities in first-order phase transitions is of great importance for the prediction of gravitational wave signals and the matter-antimatter asymmetry. However, it is a challenging task which typically depends on the underlying particle physics model. Recently, it has been shown that assuming local thermal equilibrium can provide a good approximation when calculating the bubble wall velocity. In this paper, we provide a model-independent determination of bubble wall velocities in local thermal equilibrium. Our results show that, under the reasonable assumption that the sound speeds in the plasma are approximately uniform, the hydrodynamics can be fully characterized by four quantities: the phase strength $α_n$, the ratio of the enthalpies in the broken and symmetric phases, $Ψ_n$, and the sound speeds in both phases, $c_s$ and $c_b$. We provide a code snippet that allows for a determination of the wall velocity and energy fraction in local thermal equilibrium in any model. In addition, we present a fit function for the wall velocity in the case $c_s = c_b = 1/\sqrt 3$.
description: 34 pages, 6 figures; v2 matches published version
Impact of nuclear matrix element calculations for current and future neutrinoless double beta decay searches
Creators: name: Pompa, Federica
name: Schwetz, Thomas
name: Zhu, Jing-Yu
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Nuclear matrix elements (NME) are a crucial input for the interpretation of neutrinoless double beta decay data. We consider a representative set of recent NME calculations from different methods and investigate the impact on the present bound on the effective Majorana mass $m_{ββ}$ by performing a combined analysis of the available data as well as on the sensitivity reach of future projects. A crucial role is played by the recently discovered short-range contribution to the NME, induced by light Majorana neutrino masses. Depending on the NME model and the relative sign of the long- and short-range contributions, the current $3σ$ bound can change between $m_{ββ} < 40$ meV and 600 meV. The sign-uncertainty may either boost the sensitivity of next-generation experiments beyond the region for $m_{ββ}$ predicted for inverted mass ordering or prevent even advanced setups to reach this region. Furthermore, we study the possibility to distinguish between different NME calculations by assuming a positive signal and by combining measurements from different isotopes. Such a discrimination will be impossible if the relative sign of the long- and short-range contribution remains unknown, but can become feasible if $m_{ββ} \gtrsim 40$ meV and if the relative sign is known to be positive. Sensitivities will be dominated by the advanced $^{76}$Ge and $^{136}$Xe setups assumed here, but NME model-discrimination improves if data from a third isotope is added, e.g., from $^{130}$Te or $^{100}$Mo.
description: 29 pages, 14 figures, the version to be published in JHEP
On the frequency of star-forming galaxies in the vicinity of powerful AGNs: The case of SMM J04135+10277
Creators: name: Fogasy, J.
name: Knudsen, K. K.
name: Lagos, C. D. P.
name: Drouart, G.
name: Gonzalez-Perez, V.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: (Abridged) In the last decade several massive molecular gas reservoirs were found <100 kpc distance from active galactic nuclei (AGNs), residing in gas-rich companion galaxies. The study of AGN-gas-rich companion systems opens the opportunity to determine whether the stellar mass of massive local galaxies was formed in their host after a merger event or outside of their host galaxy in a close starbursting companion and later incorporated via mergers. We study the quasar-companion galaxy system of SMM J04135+10277 (z=2.84) and investigate the expected frequency of quasar-starburst galaxy pairs at high redshift using a cosmological galaxy formation model. We use archive data and new APEX ArTeMiS data to construct and model the spectral energy distribution of SMM J04135. We also carry out a comprehensive analysis of the cosmological galaxy formation model GALFORM with the aim of characterising how typical the system of SMM J04135 is and whether quasar-star-forming galaxy pairs may constitute an important stage in galaxy evolution. The companion galaxy of SMM J04135 is a heavily dust-obscured starburst galaxy with a median star formation rate (SFR) of $700\,\rm{M_{\odot}\,yr^{-1}}$, median dust mass of $5.1\times 10^9\,\rm{M_{\odot}}$ and median dust luminosity of $\textrm 9.3 \times 10^{12}\,\rm{L_{\odot}}$. Our simulations, performed at z=2.8, suggest that SMM J04135 is not unique. In fact, at a distance of <100 kpc, 22% of our simulated quasar sample have at least one companion galaxy of a stellar mass $>10^8\, \rm{M_{\odot}}$, and 0.3% have at least one highly star-forming companion ($\rm{SFR}>100\,\rm{M_{\odot}\,yr^{-1}}$). Our results suggest that quasar-gas-rich companion galaxy systems are common phenomena in the early Universe and the high incidence of companions makes the study of such systems crucial to understand the growth and hierarchical build-up of galaxies and black holes.
description: 10 pages, 5 figures, accepted for publication in A&A
Cosmic Infrared Background anisotropies as a window into primordial non-Gaussianity
Creators: name: Tucci, Marco
name: Desjacques, Vincent
name: Kunz, Martin
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The angular power spectrum of the cosmic infrared background (CIB) is a sensitive probe of the local primordial bispectrum. CIB measurements are integrated over a large volume so that the scale dependent bias from the primordial non-Gaussianity leaves a strong signal in the CIB power spectrum. Although galactic dust dominates over the non-Gaussian CIB signal, it is possible to mitigate the dust contamination with enough frequency channels, especially if high frequencies such as the Planck 857 GHz channel are available. We show that, in this case, measurements of the cosmic microwave background from future space missions should be able to probe the local bispectrum shape down to an amplitude |f_nl| < 1.
description: 19 pages, 9 figures, submitted to MNRAS
Supporting Information from Propensity for selfing varies within a population of hermaphroditic snails: coexistence of selfers, outcrossers and mixed-mating individuals
Creators: name: Felmy, Anja
name: Streiff, Alena B.
name: Jokela, Jukka
Publisher: name: The Royal Society
Year: 2023
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Evolutionary Biology
subject: Animal Behaviour

description: Supporting methods, figures and tables
R Markdown Document from Propensity for selfing varies within a population of hermaphroditic snails: coexistence of selfers, outcrossers and mixed-mating individuals
Creators: name: Felmy, Anja
name: Streiff, Alena B.
name: Jokela, Jukka
Publisher: name: The Royal Society
Year: 2023
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Evolutionary Biology
subject: Animal Behaviour

description: All R code and output
Discovery of A New Retrograde Trans-Neptunian Object: Hint of A Common Orbital Plane for Low Semi-Major Axis, High Inclination TNOs and Centaurs
Creators: name: Chen, Ying-Tung
name: Lin, Hsing Wen
name: Holman, Matthew J.
name: Payne, Matthew J.
name: Fraser, Wesley C.
name: Lacerda, Pedro
name: Ip, Wing-Huen
name: Chen, Wen-Ping
name: Kudritzki, Rolf-Peter
name: Jedicke, Robert
name: Wainscoat, Richard J.
name: Tonry, John L.
name: Magnier, Eugene A.
name: Waters, Christopher
name: Kaiser, Nick
name: Wang, Shiang-Yu
name: Lehner, Matthew
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Although the majority of Centaurs are thought to have originated in the scattered disk, with the high-inclination members coming from the Oort cloud, the origin of the high inclination component of trans-Neptunian objects (TNOs) remains uncertain. We report the discovery of a retrograde TNO, which we nickname "Niku", detected by the Pan-STARRS 1 Outer Solar System Survey. Our numerical integrations show that the orbital dynamics of Niku are very similar to that of 2008 KV$_{42}$ (Drac), with a half-life of $\sim 500$ Myr. Comparing similar high inclination TNOs and Centaurs ($q > 10$ AU, $a < 100$ AU and $i > 60^\circ$), we find that these objects exhibit a surprising clustering of ascending node, and occupy a common orbital plane. This orbital configuration has high statistical significance: 3.8-$σ$. An unknown mechanism is required to explain the observed clustering. This discovery may provide a pathway to investigate a possible reservoir of high-inclination objects.
description: 18 pages, 4 figures, 1 table, accepted for publication in ApJ Letters
Octupole deformation of nuclei near the spherical closed-shell configurations
Creators: name: Arita, Ken-ichiro
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The origin of octupole deformation for even-even nuclei near the doubly-closed shell configurations are investigated by means of the semiclassical periodic orbit theory. In order to focus on the change of shell structure due to deformation, a simple infinite-well potential model is employed with octupole shape parametrized by merging a sphere and a paraboloid. Attention is paid to the contributions of the degenerate families of periodic orbits (POs) confined in the spherical portion of the potential, that are expected to partially preserve the spherical shell effect up to considerably large value of the octupole parameter. The contribution of those POs to the semiclassical trace formula plays an important role in bringing about shell energy gain due to octupole deformation in the system with a few particles added to spherical closed-shell configurations.
description: accepted version for publication in Phys. Rev. C
A second look at transition amplitudes in (2+1)-dimensional causal dynamical triangulations
Creators: name: Cooperman, Joshua H.
name: Lee, Kyle
name: Miller, Jonah M.
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Studying transition amplitudes in (2+1)-dimensional causal dynamical triangulations, Cooperman and Miller discovered speculative evidence for Lorentzian quantum geometries emerging from its Euclidean path integral. On the basis of this evidence, Cooperman and Miller conjectured that Lorentzian de Sitter spacetime, not Euclidean de Sitter space, dominates the ground state of the quantum geometry of causal dynamical triangulations on large scales, a scenario akin to that of the Hartle-Hawking no-boundary proposal in which Lorentzian spacetimes dominate a Euclidean path integral. We argue against this conjecture: we propose a more straightforward explanation of their findings, and we proffer evidence for the Euclidean nature of these seemingly Lorentzian quantum geometries. This explanation reveals another manner in which the Euclidean path integral of causal dynamical triangulations behaves correctly in its semiclassical limit--the implementation and interaction of multiple constraints.
description: 19+7 pages, 14 figures
Hyperfine interactions in open-shell planar $sp^2$-carbon nanostructures
Creators: name: Sengupta, Sanghita
name: Frederiksen, Thomas
name: Giedke, Geza
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We investigate hyperfine interaction (HFI) using density-functional theory for several open-shell planar $sp^2$-carbon nanostructures displaying $π$ magnetism. Our prototype structures include both benzenoid ([$n$]triangulenes and a graphene nanoribbon) as well as non-benzenoid (indene, fluorene, and indene[2,1-b]fluorene) molecules. Our results obtained with ORCA indicate that isotropic Fermi contact and anisotropic dipolar terms contribute in comparable strength, rendering the HFI markedly anisotropic. We find that the magnitude of HFI in these molecules can reach more than 100 MHz, thereby opening up the possibility of experimental detection via methods such as electron spin resonance-scanning tunneling microscopy (ESR-STM). Using these results, we obtain empirical models based on $π$-spin polarizations at carbon sites. These are defined by generic $sp^{2}$ HFI fit parameters which are derived by matching the computed HFI couplings to $π$-spin polarizations computed with methods such as ORCA, SIESTA, or mean-field Hubbard (MFH) models. This approach successfully describes the Fermi contact and dipolar contributions for $^{13}$C and $^{1}$H nuclei. These fit parameters allow to obtain hyperfine tensors for large systems where existing methodology is not suitable or computationally too expensive. As an example, we show how HFI scales with system size in [$n$]triangulenes for large $n$ using MFH. We also discuss some implications of HFI for electron-spin decoherence and for coherent nuclear dynamics.
description: 22 pages, 9 figures; version published Phys.Rev.B
Tunable fiber source of entangled UV-C and infrared photons
Creators: name: Lopez-Huidobro, Santiago
name: Chekhova, Maria V.
name: Joly, Nicolas Y.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Pairs of entangled photons -- biphotons -- are indispensable in quantum applications. However, some important spectral ranges, like ultraviolet, have been inaccessible to them so far. Here, we use four-wave mixing in a xenon-filled single-ring photonic crystal fiber to generate biphotons with one of the photons in the ultraviolet and its entangled partner in the infrared spectral range. We tune the biphotons in frequency by varying the gas pressure inside the fiber and thus tailoring the fiber dispersion landscape. The ultraviolet photons are tunable from 271 nm to 235 nm and their entangled partners, from 764 nm to 1342 nm, respectively. The tunability up to 170 THz is achieved by adjusting the gas pressure by only 0.57 bar. At 1.32 bar, the photons of a pair are separated by more than 2 octaves. The access to ultraviolet wavelengths opens the possibility for spectroscopy and sensing with undetected photons in this spectral range.
description: 6 pages, 6 figures
Modelling Force-Free Neutron Star Magnetospheres using Physics-Informed Neural Networks
Creators: name: Urbán, Jorge F.
name: Stefanou, Petros
name: Dehman, Clara
name: Pons, José A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Using Physics-Informed Neural Networks (PINNs) to solve a specific boundary value problem is becoming more popular as an alternative to traditional methods. However, depending on the specific problem, they could be computationally expensive and potentially less accurate. The functionality of PINNs for real-world physical problems can significantly improve if they become more flexible and adaptable. To address this, our work explores the idea of training a PINN for general boundary conditions and source terms expressed through a limited number of coefficients, introduced as additional inputs in the network. Although this process increases the dimensionality and is computationally costly, using the trained network to evaluate new general solutions is much faster. Our results indicate that PINN solutions are relatively accurate, reliable, and well-behaved. We applied this idea to the astrophysical scenario of the magnetic field evolution in the interior of a neutron star connected to a force-free magnetosphere. Solving this problem through a global simulation in the entire domain is expensive due to the elliptic solver's needs for the exterior solution. The computational cost with a PINN was more than an order of magnitude lower than the similar case solved with classical methods. These results pave the way for the future extension to 3D of this (or a similar) problem, where generalised boundary conditions are very costly to implement.
description: 11 pages, 10 figures, submitted for publication in MNRAS
Reconceiling the orbital and physical properties of the martian moons
Creators: name: Ronnet, Thomas
name: Vernazza, Pierre
name: Mousis, Olivier
name: Brugger, Bastien
name: Beck, Pierre
name: Devouard, Bertrand
name: Witasse, Olivier
name: Cipriani, Fabrice
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The origin of Phobos and Deimos is still an open question. Currently, none of the three proposed scenarios for their origin (intact capture of two distinct outer solar system small bodies, co-accretion with Mars, and accretion within an impact-generated disk) is able to reconcile their orbital and physical properties. Here, we investigate the expected mineralogical composition and size of the grains from which the moons once accreted assuming they formed within an impact-generated accretion disk. A comparison of our results with the present day spectral properties of the moons allows us to conclude that their building blocks cannot originate from a magma phase, thus preventing their formation in the innermost part of the disk. Instead, gas-to-solid condensation of the building blocks in the outer part of an extended gaseous disk is found as a possible formation mechanism as it does allow reproducing both the spectral and physical properties of the moons. Such a scenario may finally reconcile their orbital and physical properties alleviating the need to invoke an unlikely capture scenario to explain their physical properties.
3D Radiation-Hydrodynamic Simulations Resolving Interior of Rapidly Accreting Primordial Protostar
Creators: name: Kimura, Kazutaka
name: Hosokawa, Takashi
name: Sugimura, Kazuyuki
name: Fukushima, Hajime
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Direct collapse of supermassive stars is a possible pathway to form supermassive black hole seeds at high redshifts. Whereas previous three-dimensional (3D) simulations demonstrate that supermassive stars form via rapid mass accretion, those resolving the stellar interior have been limited. We here report 3D radiation-hydrodynamic (RHD) simulations following the evolution of rapidly accreting protostars resolving the stellar interior. We use an adaptive mesh refinement code with our newly developed RHD solver employing an explicit M1 closure method. We follow the early evolution until the stellar mass reaches $\sim 10~M_\odot$ from two different initial configurations of spherical and turbulent clouds. We demonstrate that, in both the cases, a swollen protostar whose radius is $100\mathrm{-}1000~R_\odot$ appears, as predicted by the stellar evolution calculations. Its effective temperature remains a few thousand Kelvin, and the radiative feedback by ionizing photons is too weak to disturb the accretion flow up to the epoch examined in this work. In the turbulent case, the protostar rotates rapidly at more than 0.4 times the Keplerian velocity owing to the angular momentum provided by the initial turbulence. The protostar approximates an oblate spheroid, and its equatorial radius is more than twice the polar radius. Our results suggest that we need to consider the rapid stellar rotation to elucidate the realistic 3D protostellar evolution in the supermassive star formation.
description: 9 pages, 5 figures, accepted to ApJ
Ring Formation around Giant Planets by Tidal Disruption of a Single Passing Large Kuiper Belt Object
Creators: name: Hyodo, Ryuki
name: Charnoz, Sébastien
name: Ohtsuki, Keiji
name: Genda, Hidenori
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The origin of rings around giant planets remains elusive. Saturn's rings are massive and made of 90-95% of water ice. In contrast, the much less massive rings of Uranus and Neptune are dark and likely to have higher rock fraction. Here we investigate, for the first time, the tidal disruption of a passing object, including the subsequent formation of planetary rings. First, we perform SPH simulations of the tidal destruction of big differentiated objects ($M_{\rm body}=10^{21-23}$) that experience close encounters with Saturn or Uranus. We find that about $0.1-10$% of the mass of the passing body is gravitationally captured around the planet. However, these fragments are initially big chunks and have highly eccentric orbits around the planet. Then, we perform N-body simulations including the planet's oblateness, starting with data obtained from the SPH simulations. Our N-body simulations show that the chunks are tidally destroyed during their next several orbits. Their individual orbits then start to precess incoherently around the planet's equator, which enhances their encounter velocities on longer-term evolution, resulting in more destructive impacts. These collisions would damp their eccentricities resulting in a progressive collapse of the debris cloud into a thin equatorial and low-eccentricity ring. These high energy impacts are expected to be catastrophic enough to produce small particles. Our numerical results also show that the mass of formed rings is large enough to explain current rings including inner regular satellites around Saturn and Uranus. In the case of Uranus, a body can go deeper inside the planet's Roche limit resulting in a more efficient capture of rocky material compared to Saturn's case in which mostly ice is captured. Thus, our results can naturally explain the compositional difference between the rings of Saturn, Uranus and Neptune.
description: 33 pages, 21 figures; accepted in Icarus
Cross-sections for neutral atoms and molecules collisions with charged spherical nanoparticle
Creators: name: Shneider, M. N.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: The paper presents cross sections for collisions of neutral atoms/molecules with a charged nanoparticle, which is the source of the dipole potential. The accuracy of the orbital limited motion (OLM) approximation is estimated. It is shown that simple analytical formulas for the atoms/molecules and heat fluxes, obtained in the OLM approximation, give an error of not more than 15%, and are applicable in all reasonable range of nanoparticles and weakly ionized plasma parameters.
Coupling of three-spin qubits to their electric environment
Creators: name: Russ, Maximilian
name: Ginzel, Florian
name: Burkard, Guido
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We investigate the behavior of qubits consisting of three electron spins in double and triple quantum dots subject to external electric fields. Our model includes two independent bias parameters, $\varepsilon$ and $\varepsilon_{M}$, which both couple to external electromagnetic fields and can be controlled by gate voltages applied to the quantum dot structures. By varying these parameters one can switch the qubit type by shifting the energies in the single quantum dots thus changing the electron occupancy in each dot. Starting from the asymmetric resonant (ARX) exchange qubit with a (2,0,1) and (1,0,2) charge admixture one can smoothly cross over to the resonant exchange (RX) qubit with a detuned (1,1,1) charge configuration, and to the exchange-only (EO) qubit with the same charge configuration but equal energy levels down to the hybrid qubits with (1,2,0) and (0,2,1) charge configurations. Here, ($l,m,n$) describes a configuration with $l$ electrons in the left dot, $m$ electrons in the center dot, and $n$ electrons in the right dot. We first focus on random electromagnetic field fluctuations, i.e., "charge noise", at each quantum dot resulting in dephasing of the qubit and provide a complete map of the resulting dephasing time as a function of the bias parameters. We pay special attention to the so-called sweet spots and double sweet spots of the system which are least susceptible to noise. In the second part we investigate the coupling of the qubit system to the coherent quantized electromagnetic field in a superconducting strip-line cavity and also provide a complete map of the coupling strength as a function of the bias parameters. We analyze the asymmetric qubit-cavity coupling via $\varepsilon$ and the symmetric coupling via $\varepsilon_{M}$.
description: 17 pages, 8 figures
Flavor solitons in dense neutrino gases
Creators: name: Fiorillo, Damiano F. G.
name: Raffelt, Georg
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We consider a dense neutrino gas in the "fast-flavor limit" (vanishing neutrino masses). For the first time, we identify exact solutions of the nonlinear wave equation in the form of solitons. They can propagate with both sub- or superluminal speed, the latter not violating causality. The soliton with infinite speed is a homogeneous solution and coincides with the usual fast-flavor pendulum except that it swings only once instead of being periodic. The subluminal soliton in the static limit corresponds to a one-swing "spatial pendulum". A necessary condition for such solutions to exist is a ``crossed'' neutrino angle distribution. Based on the Nyquist criterion, we derive a new sufficient condition without solving the dispersion relation. The solitons are very fragile: they are as unstable as the homogeneous neutrino gas alone. Moreover, in the presence of matter, only the solution survives that is homogeneous in a frame comoving with the matter current. Generally, the matter effect cannot be eliminated by transformations in flavor space, but instead has a real physical impact.
description: 12 pages, 8 figures, plus appendices