Miracle-dz/UniFAR-FTUs huggingface dataset:
The impact of a massive star cluster on its surrounding matter in the Antennae overlap region

Super star clusters (SSCs), likely the progenitors of globular clusters, are one of the most extreme forms of star formation. Understanding how SSCs form is an observational challenge. Theoretical studies establish that, to form such clusters, the dynamical timescale of their parent clouds has to be shorter than the timescale of the disruption of their parent clouds by stellar feedback. However, due to insufficient observational support, it is still unclear how feedback from SSCs acts on their surrounding matter. Studying feedback in SSCs is essential to understand how such clusters form. Based on ALMA and VLT observations, we study this process in a SSC in the overlap region of the Antennae galaxies. We analyze a unique massive (~10^7 Msun) and young (1-3.5 Myr) SSC, still associated with compact molecular and ionized gas emission. The cluster has two CO velocity components, a low velocity one spatially associated with the cluster and a high velocity one distributed in a bubble-like shape around the cluster. Our results on the low velocity component suggest that this gas did not participate in the formation of the SSC. We propose that most of the parent cloud has already been blown away, accelerated at the early stages of the SSC evolution by radiation pressure, in a timescale ~1 Myr. The high velocity component may trace outflowing molecular gas from the parent cloud. Supporting evidence is found in shock heated H2 gas. The low velocity component may be gas that was near the SSC when it formed but not part of its parent cloud or clumps that migrated from the SGMC environment. This gas would be dispersed by stellar winds and supernova explosions. Within ~100 pc from the cluster, we estimate SFE>17%, smaller than the theoretical limit of 30% needed to form a bound cluster. Further higher spatial resolution observations are needed to test and quantify our proposed scenario.
Estimating the dust production rate of carbon stars in the Small Magellanic Cloud

We employ newly computed grids of spectra reprocessed by dust for estimating the total dust production rate (DPR) of carbon stars in the Small Magellanic Cloud (SMC). For the first time, the grids of spectra are computed as a function of the main stellar parameters, i.e. mass-loss rate, luminosity, effective temperature, current stellar mass and element abundances at the photosphere, following a consistent, physically grounded scheme of dust growth coupled with stationary wind outflow. The model accounts for the dust growth of various dust species formed in the circumstellar envelopes of carbon stars, such as carbon dust, silicon carbide and metallic iron. In particular, we employ some selected combinations of optical constants and grain sizes for carbon dust which have been shown to reproduce simultaneously the most relevant color-color diagrams in the SMC. By employing our grids of models, we fit the spectral energy distributions of $\approx$3100 carbon stars in the SMC, consistently deriving some important dust and stellar properties, i.e. luminosities, mass-loss rates, gas-to-dust ratios, expansion velocities and dust chemistry. We discuss these properties and we compare some of them with observations in the Galaxy and LMC. We compute the DPR of carbon stars in the SMC, finding that the estimates provided by our method can be significantly different, between a factor $\approx2-5$, than the ones available in the literature. Our grids of models, including the spectra and other relevant dust and stellar quantities, are publicly available at this http URL
Impact of Weak Lensing Mass Calibration on eROSITA Galaxy Cluster Cosmological Studies – a Forecast

We forecast the impact of weak lensing (WL) cluster mass calibration on the cosmological constraints from the X-ray selected galaxy cluster counts in the upcoming eROSITA survey. We employ a prototype cosmology pipeline to analyze mock cluster catalogs. Each cluster is sampled from the mass function in a fiducial cosmology and given an eROSITA count rate and redshift, where count rates are modeled using the eROSITA effective area, a typical exposure time, Poisson noise and the scatter and form of the observed X-ray luminosity– and temperature–mass–redshift relations. A subset of clusters have mock shear profiles to mimic either those from DES and HSC or from the future Euclid and LSST surveys. Using a count rate selection, we generate a baseline cluster cosmology catalog that contains 13k clusters over 14,892 deg2 of extragalactic sky. Low mass groups are excluded using raised count rate thresholds at low redshift. Forecast parameter uncertainties for ΩM, σ8 and w are 0.023 (0.016; 0.014), 0.017 (0.012; 0.010), and 0.085 (0.074; 0.071), respectively, when adopting DES+HSC WL (Euclid; LSST), while marginalizing over the sum of the neutrino masses. A degeneracy between the distance–redshift relation and the parameters of the observable–mass scaling relation limits the impact of the WL calibration on the w constraints, but with BAO measurements from DESI an improved determination of w to 0.043 becomes possible. With Planck CMB priors, ΩM (σ8) can be determined to 0.005 (0.007), and the summed neutrino mass limited to ∑mν < 0.241 eV (at 95%). If systematics on the group mass scale can be controlled, the eROSITA group and cluster sample with 43k objects and LSST WL could constrain ΩM and σ8 to 0.007 and w to 0.050.
Dispersion Measure Variation of Repeating Fast Radio Burst Sources

The repeating fast radio burst (FRB) 121102 was recently localized in a dwarf galaxy at a cosmological distance. The dispersion measure (DM) derived for each burst from FRB 121102 so far has not shown significant evolution, even though an apparent increase was recently seen with newly detected VLA bursts. It is expected that more repeating FRB sources may be detected in the future. In this work, we investigate a list of possible astrophysical processes that might cause DM variation of a particular FRB source. The processes include (1) cosmological scale effects such as Hubble expansion and large-scale structure fluctuations; (2) FRB local effects such as gas density fluctuation, expansion of a supernova remnant (SNR), a pulsar wind nebula, and an H ii region; and (3) the propagation effect due to plasma lensing. We find that the DM variations contributed by the large-scale structure are extremely small, and any observable DM variation is likely caused by the plasma local to the FRB source. In addition to mechanisms that decrease DM over time, we suggest that an FRB source in an expanding SNR around a nearly neutral ambient medium during the deceleration (Sedov–Taylor and snowplow) phases or in a growing H ii region can increase DM. Some effects (e.g., an FRB source moving in an H ii region or plasma lensing) can produce either positive or negative DM variations. Future observations of DM variations of FRB 121102 and other repeating FRB sources can provide important clues regarding the physical origin of these sources.
A new test of f(R) gravity with the cosmological standard rulers in radio quasars

As an important candidate gravity theory alternative to dark energy, a class of f(R) modified gravity, which introduces a perturbation of the Ricci scalar R in the Einstein-Hilbert action, has been extensively applied to cosmology to explain the acceleration of the universe. In this paper, we focus on the recently-released VLBI observations of the compact structure in intermediate-luminosity quasars combined with the angular-diameter-distance measurements from galaxy clusters, which consists of 145 data points performing as individual cosmological standard rulers in the redshift range 0.023 ≤ z ≤ 2.80, to investigate observational constraints on two viable models in f(R) theories within the Palatini formalism: f1(R) = R−a/Rb and f2(R)=R−aR/R+ab. We also combine the individual standard ruler data with the observations of CMB and BAO, which provides stringent constraints. Furthermore, two model diagnostics, Om(z) and statefinder, are also applied to distinguish the two f(R) models and ΛCDM model. Our results show that (1) The quasars sample performs very well to place constraints on the two f(R) cosmologies, which indicates its potential to act as a powerful complementary probe to other cosmological standard rulers. (2) The ΛCDM model, which corresponds to b = 0 in the two f(R) cosmologies is still included within 1σ range. However, there still exists some possibility that ΛCDM may not the best cosmological model preferred by the current high-redshift observations. (3) Given the current standard ruler data, the information criteria indicate that the cosmological constant model is still the best one, while the f1(R) model gets the smallest observational support. (4) The f2(R) model, which evolves quite different from f1(R) model at early times, still significantly deviates from both f1(R) and ΛCDM model at the present time.
Rotation-supported Neutrino-driven Supernova Explosions in Three Dimensions and the Critical Luminosity Condition

We present the first self-consistent, 3D core-collapse supernova simulations performed with the Prometheus-Vertex code for a rotating progenitor star. Besides using the angular momentum of the 15 M⊙ model as obtained in the stellar evolution calculation with an angular frequency of ∼10−3 rad s−1 (spin period of more than 6000 s) at the Si/Si–O interface, we also computed 2D and 3D cases with no rotation and with a ∼300 times shorter rotation period and different angular resolutions. In 2D, only the nonrotating and slowly rotating models explode, while rapid rotation prevents an explosion within 500 ms after bounce because of lower radiated neutrino luminosities and mean energies and thus reduced neutrino heating. In contrast, only the fast-rotating model develops an explosion in 3D when the Si/Si–O interface collapses through the shock. The explosion becomes possible by the support of a powerful standing accretion shock instability spiral mode, which compensates for the reduced neutrino heating and pushes strong shock expansion in the equatorial plane. Fast rotation in 3D leads to a “two-dimensionalization” of the turbulent energy spectrum (yielding roughly a −3 instead of a −5/3 power-law slope at intermediate wavelengths) with enhanced kinetic energy on the largest spatial scales. We also introduce a generalization of the “universal critical luminosity condition” of Summa et al. to account for the effects of rotation, and we demonstrate its viability for a set of more than 40 core-collapse simulations, including 9 and 20 M⊙ progenitors, as well as black-hole-forming cases of 40 and 75 M⊙ stars to be discussed in forthcoming papers.
STUDY OF BL Lac VLBA DATA AT 8 AND 15 GHz IN A SUPER-RESOLUTION MODE

In this work, we show Very Long Baseline Array data at 8 GHz (RRFID) and 15 GHz (MOJAVE) of BL Lac from 1995 to 2007 by examining the structure in the maps given by the CLEAN-point components (represented by a restoring beam of 0.1 mas). The CLEAN-point maps show a well-ordered train of individual points in the inner core jet. The result shows a narrow elongated stationary component at about 1.5 mas from the core which was interpreted as superposition of trailing components. The inner core-jet structure shows ballistic motion and a precessing ejection nozzle period of 26 years.
Transfer of Vertical Graphene Nanosheets onto Flexible Substrates towards Supercapacitor Application

Vertical graphene nanosheets (VGNs) are the material of choice for next-generation electronic device applications. The growing demand for flexible devices in electronic industry brings in restriction on growth temperature of the material of interest. However, VGNs with better structural quality is usually achieved at high growth temperatures. The difficulty associated with the direct growth on flexible substrates can overcome by adopting an effective strategy of transferring the well grown VGNs onto arbitrary flexible substrates through soft chemistry route. Hence, we demonstrated a simple, inexpensive and scalable technique for the transfer of VGNs onto arbitrary substrates without disrupting its morphology and structural properties. After transfer, the morphology, chemical structure and electronic properties are analyzed by scanning electron microscopy, Raman spectroscopy and four probe resistive methods, respectively. Associated characterization investigation indicates the retention of morphological, structural and electrical properties of transferred VGNs compared to as-grown one. Furthermore the storage capacity of the VGN’s transferred onto flexible substrates is also examined. A very lower sheet resistance of 0.67 kΩ/□ and excellent supercapacitance of 158 μF/cm with 91.4% retention after 2000 cycles confirms the great prospective of this damage-free transfer approach of VGNs for flexible nanoelectronic device applications. Corresponding authors: subrataghosh.phys@gmail.com (Subrata Ghosh); poalki@igcar.gov. in (S. R. Polaki) † both authors equally contributed to the work
Nonperturbative investigations of SU(3) gauge theory with eight dynamical flavors

We present our lattice studies of SU(3) gauge theory with ${N}_{f}=8$ degenerate fermions in the fundamental representation. Using nHYP-smeared staggered fermions we study finite-temperature transitions on lattice volumes as large as ${L}^{3}\ifmmode\times\else\texttimes\fi{}{N}_{t}=4{8}^{3}\ifmmode\times\else\texttimes\fi{}24$, and the zero-temperature composite spectrum on lattice volumes up to $6{4}^{3}\ifmmode\times\else\texttimes\fi{}128$. The spectrum indirectly indicates spontaneous chiral symmetry breaking, but finite-temperature transitions with fixed ${N}_{t}\ensuremath{\le}24$ enter a strongly coupled lattice phase as the fermion mass decreases, which prevents a direct confirmation of spontaneous chiral symmetry breaking in the chiral limit. In addition to the connected spectrum we focus on the lightest flavor-singlet scalar particle. We find it to be degenerate with the pseudo-Goldstone states down to the lightest masses reached so far by nonperturbative lattice calculations. Using the same lattice approach, we study the behavior of the composite spectrum when the number of light fermions is changed from eight to four. A heavy flavor-singlet scalar in the 4-flavor theory affirms the contrast between QCD-like dynamics and the low-energy behavior of the 8-flavor theory.
Presupernova Evolution and Explosive Nucleosynthesis of Rotating Massive Stars in the Metallicity Range −3 ≤ [Fe/H] ≤ 0

We present a new grid of presupernova models of massive stars extending in mass between 13 and 120 , covering four metallicities (i.e., [Fe/H] = 0, −1, −2, and −3) and three initial rotation velocities (i.e., 0, 150, and 300 km s−1). The explosion has been simulated following three different assumptions in order to show how the yields depend on the remnant mass−initial mass relation. An extended network from H to Bi is fully coupled to the physical evolution of the models. The main results can be summarized as follows. (a) At solar metallicity, the maximum mass exploding as a red supergiant (RSG) is of the order of 17 in the nonrotating case, with the more massive stars exploding as Wolf–Rayet (WR) stars. All rotating models, conversely, explode as WR stars. (b) The interplay between the core He-burning and the H-burning shell, triggered by the rotation-induced instabilities, drives the synthesis of a large primary amount of all the products of CNO, not just . A fraction of them greatly enriches the radiative part of the He core (and is responsible for the large production of F), and a fraction enters the convective core, leading therefore to an important primary neutron flux able to synthesize heavy nuclei up to Pb. (c) In our scenario, remnant masses of the order of those inferred from the first detections of gravitational waves (GW 150914, GW 151226, GW 170104, GW 170814) are predicted at all metallicities for none or moderate initial rotation velocities.
Age determination for 269 Gaia DR2 open clusters

Context. The Gaia Second Data Release provides precise astrometry and photometry for more than 1.3 billion sources. This catalog opens a new era concerning the characterization of open clusters and test stellar models, paving the way for better understanding of the disk properties. Aims. The aim of the paper is to improve the knowledge of cluster parameters, using only the unprecedented quality of the Gaia photometry and astrometry. Methods. We have made use of the membership determination based on the precise Gaia astrometry and photometry. We applied an automated Bayesian tool, BASE-9, to fit stellar isochrones on the observed G, GBP, GRP magnitudes of the high probability member stars. Results. We derive parameters such as age, distance modulus, and extinction for a sample of 269 open clusters, selecting only low reddening objects and discarding very young clusters, for which techniques other than isochrone-fitting are more suitable for estimating ages.
PHIBSS: exploring the dependence of the CO–H2 conversion factor on total mass surface density at z<1.5

We present an analysis of the relationship between the CO-H$_{2}$ conversion factor ($\alpha_{\rm CO}$) and total mass surface density ($\Sigma_{\rm tot}$) in star-forming galaxies at $z < 1.5$. Our sample, which is drawn from the IRAM Plateau de Bure HIgh-$z$ Blue Sequence Survey (PHIBSS) and the CO Legacy Database for GASS (COLD GASS), includes 'normal,' massive star-forming galaxies that dominate the evolution of the cosmic star formation rate (SFR) at this epoch and probe the $\Sigma_{\rm tot}$ regime where the strongest variation in $\alpha_{\rm CO}$ is observed. We constrain $\alpha_{\rm CO}$ via existing CO observations, measurements of the star formation rate, and an assumed molecular gas depletion time ($t_{\rm dep}$=$M_{\rm gas}$/SFR) --- the latter two of which establish the total molecular gas mass independent of the observed CO luminosity. For a broad range of adopted depletion times, we find that $\alpha_{\rm CO}$ is independent of total mass surface density, with little deviation from the canonical Milky Way value. This runs contrary to a scenario in which $\alpha_{\rm CO}$ decreases as surface density increases within the extended clouds of molecular gas that potentially fuel clumps of star formation in $z\sim1$ galaxies, similar to those observed in local ULIRGs. Instead, our results suggest that molecular gas, both at $z\sim0$ and $z\sim1$, is primarily in the form of self-gravitating molecular clouds. While CO observations suggest a factor of $\sim3$ reduction in the average molecular gas depletion time between $z \sim 0$ and $z\sim1$, we find that, for typical galaxies, the structure of molecular gas and the process of star formation at $z \sim 1$ is otherwise remarkably similar to that observed in local star-forming systems.
ALMA Reveals Molecular Cloud N55 in the Large Magellanic Cloud as a Site of Massive Star Formation

We present the molecular cloud properties of N55 in the Large Magellanic Cloud using 12CO(1–0) and 13CO(1–0) observations obtained with Atacama Large Millimeter Array. We have done a detailed study of molecular gas properties, to understand how the cloud properties of N55 differ from Galactic clouds. Most CO emission appears clumpy in N55, and molecular cores that have young stellar objects (YSOs) show larger linewidths and masses. The massive clumps are associated with high and intermediate mass YSOs. The clump masses are determined by local thermodynamic equilibrium and virial analysis of the 12CO and 13CO emissions. These mass estimates lead to the conclusion that (a) the clumps are in self-gravitational virial equilibrium, and (b) the 12CO(1–0)-to-H2 conversion factor, X CO , is 6.5 × 1020 cm−2 (K km s−1)−1. This CO-to-H2 conversion factor for N55 clumps is measured at a spatial scale of ∼0.67 pc, which is about two times higher than the X CO value of the Orion cloud at a similar spatial scale. The core mass function of N55 clearly show a turnover below 200 M ⊙ , separating the low-mass end from the high-mass end. The low-mass end of the 12CO mass spectrum is fitted with a power law of index 0.5 ± 0.1, while for 13CO it is fitted with a power law index 0.6 ± 0.2. In the high-mass end, the core mass spectrum is fitted with a power index of 2.0 ± 0.3 for 12CO, and with 2.5 ± 0.4 for 13CO. This power law behavior of the core mass function in N55 is consistent with many Galactic clouds.
An improved characterization of bounded realness for singular delay systems and its applications

This paper is concerned with establishing a delay‐dependent bounded real lemma (BRL) for singular systems with a time delay. Without resorting to any bounding techniques for some cross terms and model transformation, a new version of BRL for such systems is proposed, which guarantees a singular system to be regular, impulse free and stable while satisfying a prescribed H∞ performance level for any delays smaller than a given upper bound. Based on this, an H∞ state feedback controller is designed via a linear matrix inequality approach. The BRL, stability as well as H∞ results developed in this paper are less conservative than existing ones in the literature, which is demonstrated by providing some numerical examples. Copyright © 2007 John Wiley & Sons, Ltd.
The role of particle, energy and momentum losses in 1D simulations of divertor detachment

A new 1D divertor plasma code, SD1D, has been used to examine the role of recombination, radiation, and momentum exchange in detachment. Neither momentum or power losses by themselves are found to be sufficient to produce a reduction in target ion flux in detachment (flux rollover); radiative power losses are required to (a) limit and reduce the ionisation source and (b) access low-target temperature, Ttarget, conditions for volumetric momentum losses. Recombination is found to play a small role at flux rollover, but as Ttarget drops to temperatures around 1 eV, it becomes a strong ion sink. In the case where radiative losses are dominated by hydrogen, the detachment threshold is identified as a minimum gradient of the energy cost per ionisation with respect to Ttarget. This is also linked to thresholds in Ttarget and in the ratio of upstream pressure to power flux. A system of determining the detached condition is developed such that the divertor solution at a given Ttarget (or lack of one) is determined by the simultaneous solution of two equations for target ion current—one dependent on power losses and the other on momentum. Depending on the detailed momentum and power loss dependence on temperature there are regions of Ttarget where there is no solution and the plasma ‘jumps’ from high to low Ttarget states. The novel analysis methods developed here provide an intuitive way to understand complex detachment phenomena, and can potentially be used to predict how changes in the seeding impurity used or recycling aspects of the divertor can be utilised to modify the development of detachment.
The Radial Acceleration Relation Is a Natural Consequence of the Baryonic Tully–Fisher Relation

Galaxies covering several orders of magnitude in stellar mass and a variety of Hubble types have been shown to follow the radial acceleration relation (RAR), a relationship between , the observed circular acceleration of the galaxy, and , the acceleration due to the total baryonic mass of the galaxy. For accelerations above , traces , asymptoting to the 1:1 line. Below this scale, there is a break in the relation such that . We show that the RAR slope, scatter, and the acceleration scale are all natural consequences of the well-known baryonic Tully–Fisher relation (BTFR). We further demonstrate that galaxies with a variety of baryonic and dark matter (DM) profiles and a wide range of dark halo and galaxy properties (well beyond those expected in Cold Dark Matter (CDM) theory) lie on the RAR if we simply require that their rotation curves satisfy the BTFR. We explore conditions needed to break this degeneracy: subkiloparsec resolved rotation curves inside of cored DM-dominated profiles and/or outside could lie on BTFR but deviate in the RAR, providing new constraints on DM.