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15861. Total ALFALFA H I fluxes for extended sources
ID:
ivo://CDS.VizieR/J/AJ/157/194
Title:
Total ALFALFA H I fluxes for extended sources
Short Name:
J/AJ/157/194
Date:
21 Oct 2021
Publisher:
CDS
Description:
A procedure is presented to improve on measurement of total H I fluxes for extended sources in the Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) survey of neutral hydrogen sources in the nearby universe. A number of tests of the procedure are detailed, and we verify that we recover all of the flux measured with much larger telescope beams. Total fluxes are reported for all sources (1) exceeding 10 Jy km/s in the {alpha}.100 catalog (Haynes et al. 2018ApJ...861...49H), or (2) with Uppsala General Catalog (Cat. VII/26) diameters 3.0 arcmin or more, or (3) ALFALFA pipeline isophotal ellipse area more than 3.0 times the Arecibo beam. Total fluxes are also provided for a number of confused pairs and small groups including one or more of those high-flux sources. These data should be of use in baryonic Tully-Fisher studies and other applications where the measurement of the total reservoir of neutral atomic gas is important.
15862. Toulouse AC Zone Data Reduced to ACRS
ID:
ivo://CDS.VizieR/I/232
Title:
Toulouse AC Zone Data Reduced to ACRS
Short Name:
I/232
Date:
21 Oct 2021
Publisher:
CDS
Description:
The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the Toulouse Zone, whose plates are centered between declinations +5 and +11 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of almost 270,000 stars on eq. J2000.0, epoch of observation. Additionally, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added for additional identification purposes.
15863. Towards Cosmicflows-4 HI data catalog
ID:
ivo://CDS.VizieR/J/A+A/646/A113
Title:
Towards Cosmicflows-4 HI data catalog
Short Name:
J/A+A/646/A113
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this study, we present an update of a compilation of line width measurements of neutral atomic hydrogen (HI) galaxy spectra at 21 cm wavelength. Our All Digital HI (ADHI) catalog consists of the previous release augmented with our new HI observations and an analysis of archival data. This study provides the required HI information to measure the distances of spiral galaxies through the application of the Tully-Fisher (TF) relation. We conducted observations at the Green Bank telescope (GBT) and reprocessed spectra obtained at the Nancay radiotelescope by the Nancay Interstellar Baryons Legacy Extragalactic Survey (NIBLES) and Kinematics of the Local Universe (KLUN) collaborations and we analyzed the recently published full completion Arecibo Legacy Fast ALFA (ALFALFA) 100% survey in order to identify galaxies with good quality HI line width measurements. This paper adds new HI data adequate for TF use for 385 galaxies observed at GBT, 889 galaxies from archival Nancay spectra, and 1515 rescaled Arecibo ALFALFA spectra. In total, this release adds 1274 new good quality measurements to the ADHI catalog. Today, the ADHI database contains 18,874 galaxies, for which 15,433 have good quality data for TF use. The final goal is to compute accurate distances to spiral galaxies, which will be included in the next generation of peculiar velocities catalog: Cosmicflows-4. This paper adds new HI data adequate for TF use for 385 galaxies observed at GBT, 889 galaxies from archival Nancay spectra, and 1515 rescaled Arecibo ALFALFA spectra. In total, this release adds 1274 new good quality measurements to the ADHI catalog. Today, the ADHI database contains 18874 galaxies, for which 15433 have good quality data for TF use. The final goal is to compute accurate distances to spiral galaxies, which will be included in the next generation of peculiar velocities catalog: Cosmicflows-4.
15864. TP-AGB stars contribution in SFR
ID:
ivo://CDS.VizieR/J/MNRAS/456/790
Title:
TP-AGB stars contribution in SFR
Short Name:
J/MNRAS/456/790
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the debated contribution from thermally pulsing asymptotic-giant-branch (TP-AGB) stars in evolutionary population synthesis models. We investigate the spectral energy distributions (SEDs) of a sample of 51 spectroscopically confirmed, high-z (1.3<z_spec_<2.7), galaxies using three evolutionary population synthesis models with strong, mild and light TP-AGB. Our sample is the largest of spectroscopically confirmed galaxies on which such models are tested so far. Galaxies were selected as passive, but we model them using a variety of star formation histories in order not to be dependent on this pre-selection. We find that the observed SEDs are best fitted with a significant contribution of TP-AGB stars or with substantial dust attenuation. Without including reddening, TP-AGB-strong models perform better and deliver solutions consistent within 1{sigma} from the best-fitted ones in the vast majority of cases. Including reddening, all models perform similarly. Using independent constraints from observations in the mid- and far-IR, we show that low/negligible dust attenuation, i.e. E(B-V)<~0.05, should be preferred for the SEDs of passively selected galaxies. Given that TP-AGB-light models give systematically older ages for passive galaxies, we suggest number counts of passive galaxies at higher redshifts as a further test to discriminate among stellar population models.
15865. Tracers of stellar mass-loss. II.
ID:
ivo://CDS.VizieR/J/ApJ/856/170
Title:
Tracers of stellar mass-loss. II.
Short Name:
J/ApJ/856/170
Date:
21 Oct 2021
Publisher:
CDS
Description:
I present integrated colors and surface brightness fluctuation magnitudes in the mid-infrared (IR), derived from stellar population synthesis models that include the effects of the dusty envelopes around thermally pulsing asymptotic giant branch (TP-AGB) stars. The models are based on the Bruzual & Charlot CB* isochrones; they are single-burst, range in age from a few Myr to 14Gyr, and comprise metallicities between Z=0.0001 and Z=0.04. I compare these models to mid-IR data of AGB stars and star clusters in the Magellanic Clouds, and study the effects of varying self-consistently the mass-loss rate, the stellar parameters, and the output spectra of the stars plus their dusty envelopes. I find that models with a higher than fiducial mass-loss rate are needed to fit the mid-IR colors of "extreme" single AGB stars in the Large Magellanic Cloud. Surface brightness fluctuation magnitudes are quite sensitive to metallicity for 4.5{mu}m and longer wavelengths at all stellar population ages, and powerful diagnostics of mass-loss rate in the TP-AGB for intermediate-age populations, between 100Myr and 2-3Gyr.
15866. Tracers of the Milky Way mass
ID:
ivo://CDS.VizieR/J/A+A/562/A134
Title:
Tracers of the Milky Way mass
Short Name:
J/A+A/562/A134
Date:
21 Oct 2021
Publisher:
CDS
Description:
We model the phase-space distribution of the kinematic tracers using general, smooth distribution functions to derive a conservative lower bound on the total mass within ~~150-200kpc. By approximating the potential as Keplerian, the phase-space distribution can be simplified to that of a smooth distribution of energies and eccentricities. Our approach naturally allows for calculating moments of the distribution function, such as the radial profile of the orbital anisotropy. We systematically construct a family of phase-space functions with the resulting radial velocity dispersion overlapping with the one obtained using data on radial motions of distant kinematic tracers, while making no assumptions about the density of the tracers and the velocity anisotropy parameter {beta} regarded as a function of the radial variable. While there is no apparent upper bound for the Milky Way mass, at least as long as only the radial motions are concerned, we find a sharp lower bound for the mass that is small. In particular, a mass value of 2.4x10^11^M_{sun}_, obtained in the past for lower and intermediate radii, is still consistent with the dispersion profile at larger radii. Compared with much greater mass values in the literature, this result shows that determining the Milky Way mass is strongly model-dependent. We expect a similar reduction of mass estimates in models assuming more realistic mass profiles.
15867. Tracing stars of MW dwarf galaxies: Sextans
ID:
ivo://CDS.VizieR/J/A+A/609/A53
Title:
Tracing stars of MW dwarf galaxies: Sextans
Short Name:
J/A+A/609/A53
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a deep and very spatially extended CTIO/DECam g and r photometric catalogue of point-sources (reaching out to ~2 magnitudes below the oldest main-sequence turn-off and covering ~20deg^2^) around the Sextans dwarf spheroidal galaxy, together with another catalogue of literature spectroscopic measurements (Walker et al., 2009, Cat. J/AJ/137/3100 and Battaglia et al., 2011, Cat. J/MNRAS/411/1013) with updated membership probabilities.
15868. Transient black hole X-ray binaries XMM obs.
ID:
ivo://CDS.VizieR/J/MNRAS/471/1468
Title:
Transient black hole X-ray binaries XMM obs.
Short Name:
J/MNRAS/471/1468
Date:
21 Oct 2021
Publisher:
CDS
Description:
All observations of Galactic X-ray binaries are affected by absorption from gas and dust in the interstellar medium (ISM) which imprints narrow (line) and broad (photoelectric edges) features on the continuum emission spectrum of the binary. Any spectral model used to fit data from a Galactic X-ray binary must therefore take account of these features; when the absorption is strong (as for most Galactic sources) it becomes important to accurately model the ISM absorption in order to obtain unbiased estimates of the parameters of the (emission) spectrum of the binary system. In this paper, we present analysis of some of the best spectroscopic data from the XMM-Newton RGS instrument using the most up-to-date photoabsorption model of the gaseous ISM ISMabs. We calculate column densities for H, O, Ne and Fe for seven transient black hole X-ray binary systems. We find that the hydrogen column densities in particular can vary greatly from those presented elsewhere in the literature. We assess the impact of using inaccurate column densities and older X-ray absorption models on spectral analysis using simulated data. We find that poor treatment of absorption can lead to large biases in inferred disc properties and that an independent analysis of absorption parameters can be used to alleviate such issues.
15869. Transient processing and analysis using AMPEL
ID:
ivo://CDS.VizieR/J/A+A/631/A147
Title:
Transient processing and analysis using AMPEL
Short Name:
J/A+A/631/A147
Date:
21 Oct 2021
Publisher:
CDS
Description:
Both multi-messenger astronomy and new high-throughput wide-field surveys require flexible tools for the selection and analysis of astrophysical transients. Here we introduce the alert management, photometry, and evaluation of light curves (AMPEL) system, an analysis framework designed for high-throughput surveys and suited for streamed data. AMPEL combines the functionality of an alert broker with a generic framework capable of hosting user-contributed code; it encourages provenance and keeps track of the varying information states that a transient displays. The latter concept includes information gathered over time and data policies such as access or calibration levels. We describe a novel ongoing real-time multi-messenger analysis using AMPEL to combine IceCube neutrino data with the alert streams of the Zwicky Transient Facility (ZTF). We also reprocess the first four months of ZTF public alerts, and compare the yields of more than 200 different transient selection functions to quantify efficiencies for selecting Type Ia supernovae that were reported to the Transient Name Server (TNS). We highlight three channels suitable for (1) the collection of a complete sample of extragalactic transients, (2) immediate follow-up of nearby transients, and (3) follow-up campaigns targeting young, extragalactic transients. We confirm ZTF completeness in that all TNS supernovae positioned on active CCD regions were detected. AMPEL can assist in filtering transients in real time, running alert reaction simulations, the reprocessing of full datasets as well as in the final scientific analysis of transient data. This is made possible by a novel way of capturing transient information through sequences of evolving states, and interfaces that allow new code to be natively applied to a full stream of alerts. This text also introduces a method by which users can design their own channels for inclusion in the AMPEL live instance that parses the ZTF stream and the real-time submission of high-quality extragalactic supernova candidates to the TNS.
15870. Transient X-ray sources in M31
ID:
ivo://CDS.VizieR/J/ApJ/643/356
Title:
Transient X-ray sources in M31
Short Name:
J/ApJ/643/356
Date:
21 Oct 2021
Publisher:
CDS
Description:
From 1999 October to 2002 August, 45 transient X-ray sources were detected in M31 by Chandra and XMM-Newton. We have performed spectral analysis of all XMM-Newton and Chandra ACIS detections of these sources, as well as flux measurements of Chandra HRC detections. The result is absorption-corrected X-ray light curves for these sources covering this 2.8yr period, along with spectral parameters for several epochs of the outbursts of most of the transient sources. We supply a catalog of the locations, outburst dates, peak observed luminosities, decay time estimates, and spectral properties of the transient sources, and we discuss similarities with Galactic X-ray novae. Duty cycle estimates are possible for eight of the transients and range from 34% to 2%; upper limits to the duty cycles are estimated for an additional 15 transients and cover a similar range. We find five transients that have rapid decay times and may be ultracompact X-ray binaries. Spectra of three of the transients suggest that they may be faint Galactic foreground sources. If even one is a foreground source, this suggests a surface density of faint transient X-ray sources of >~1deg^2^.

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