Search

Start Over Subject photometry Capability Type Simple Cone Search
4291. Sample of 114 {gamma} Doradus candidates
ID:
ivo://CDS.VizieR/J/AJ/142/39
Title:
Sample of 114 {gamma} Doradus candidates
Short Name:
J/AJ/142/39
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have carried out a photometric survey of a complete, volume-limited sample of {gamma} Doradus candidates. The sample was extracted from the Hipparcos catalog and consists of 114 stars with colors and absolute magnitudes within the range of known {gamma} Doradus stars and that also lie within a specified volume of 266600pc^3^. We devoted one year of observing time with our T12 0.8m automatic photometric telescope to acquire nightly observations of the complete sample of stars. From these survey observations, we identify 37 stars with intrinsic variability of 0.002mag or more. Of these 37 variables, 8 have already been confirmed as {gamma} Doradus stars in our earlier papers; we scheduled the remaining 29 variables on our T3 0.4m automatic telescope to acquire more intensive observations over the next two years. As promising new {gamma} Doradus candidates were identified from the photometry, we obtained complementary spectroscopic observations of each candidate with the Kitt Peak coude feed telescope. Analysis of our new photometric and spectroscopic data reveals 15 new {gamma} Doradus variables (and confirms two others), 8 new {delta} Scuti variables (and confirms one other), and 3 new variables with unresolved periodicity. Therefore, of the 114 {gamma} Doradus candidates in our volume-limited sample, we find 25 stars that are new or previously known {gamma} Doradus variables. This results in an incidence of 22% for {gamma} Doradus variability among candidate field stars for this volume of the solar neighborhood. The corresponding space density of {gamma} Doradus stars in this volume of space is 0.094 stars per 103pc^3^ or 94 stars per 106pc^3^. We provide an updated list of 86 bright, confirmed, {gamma} Doradus field stars.
4292. Sample of GOODS/CDFS early-type galaxies
ID:
ivo://CDS.VizieR/J/ApJ/635/243
Title:
Sample of GOODS/CDFS early-type galaxies
Short Name:
J/ApJ/635/243
Date:
21 Oct 2021
Publisher:
CDS
Description:
We explore the evolution of field early-type galaxies in a sample extracted from the ACS images of the southern GOODS field. The galaxies are selected by means of a nonparametric analysis, followed by visual inspection of the candidates with a concentrated surface brightness distribution. We furthermore exclude from the final sample those galaxies that are not consistent with an evolution into the Kormendy relation between surface brightness and size that is observed for z=0 ellipticals. The final set, which comprises 249 galaxies with a median redshift z_m_=0.71, represents a sample of early-type systems not selected with respect to color, with similar scaling relations as those of bona fide elliptical galaxies.
4293. Sample of 45 H{alpha}EW outliers
ID:
ivo://CDS.VizieR/J/AJ/161/277
Title:
Sample of 45 H{alpha}EW outliers
Short Name:
J/AJ/161/277
Date:
09 Dec 2021
Publisher:
CDS
Description:
In this work, we calibrate the relationship between H{alpha} emission and M-dwarf ages. We compile a sample of 892 M-dwarfs with H{alpha} equivalent width (H{alpha}EW) measurements from the literature that are either comoving with a white dwarf of known age (21 stars) or in a known young association (871 stars). In this sample we identify 7 M-dwarfs that are new candidate members of known associations. By dividing the stars into active and inactive categories according to their H{alpha}EW and spectral type (SpT), we find that the fraction of active dwarfs decreases with increasing age, and the form of the decline depends on SpT. Using the compiled sample of age calibrators, we find that H{alpha} EW and fractional H{alpha} luminosity (L_H{alpha}_/L_bol_) decrease with increasing age. H{alpha}EW for SpT<~M7 decreases gradually up until ~1Gyr. For older ages, we found only two early M dwarfs that are both inactive and seem to continue the gradual decrease. We also found 14 mid-type M-dwarfs, out of which 11 are inactive and present a significant decrease in H{alpha}EW, suggesting that the magnetic activity decreases rapidly after ~1Gyr. We fit L_H{alpha}_/L_bol_ versus age with a broken power law and find an index of -0.11_-0.01_^+0.02^ for ages <~776Myr. The index becomes much steeper at older ages, but a lack of field age-calibrators (>>1Gyr) leaves this part of the relation far less constrained. Finally, from repeated independent measurements for the same stars, we find that 94% of them have a level of H{alpha}EW variability <~5{AA} at young ages (<1Gyr).
4294. Sample of low mass stars with mu>0.1"/yr
ID:
ivo://CDS.VizieR/J/A+A/468/163
Title:
Sample of low mass stars with mu>0.1"/yr
Short Name:
J/A+A/468/163
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present details of the second part of the Southern Infrared Proper Motion Survey (SIPS). Here accurate relative astrometry allows us to reduce the minimum proper motion to 0.1"/yr. This yields 6904 objects with proper motions between our minimum cut and half an arcsecond a year. A small overspill sample with proper motions greater than this is also included. We examine our sample to identify interesting individual objects such as common proper motion binaries, potential L dwarfs and candidate nearby stars. Finally we show our survey is incomplete due to many factors, factors which we will take into account when simulating these survey results in the next paper in this series.
4295. Sample of major galaxy pairs at z=0.08-0.38
ID:
ivo://CDS.VizieR/J/AJ/139/1857
Title:
Sample of major galaxy pairs at z=0.08-0.38
Short Name:
J/AJ/139/1857
Date:
21 Oct 2021
Publisher:
CDS
Description:
We measure the strength, frequency, and timescale of tidally triggered star formation at redshift z=0.08-0.38 in a spectroscopically complete sample of galaxy pairs drawn from the magnitude-limited redshift survey of 9825 Smithsonian Hectospec Lensing Survey galaxies with R<20.3. To examine the evidence for tidal triggering, we identify a volume-limited sample of major (|{Delta}M_R_|<1.75, corresponding to mass ratio >1/5) pair galaxies with M_R_<-20.8 in the redshift range z=0.08-0.31.
4296. Sample of 141 SNe Ia
ID:
ivo://CDS.VizieR/J/A+A/644/A176
Title:
Sample of 141 SNe Ia
Short Name:
J/A+A/644/A176
Date:
21 Oct 2021
Publisher:
CDS
Description:
As part of an on-going effort to identify, understand and correct for astrophysics biases in the standardization of Type Ia supernovae (SN Ia) for cosmology, we have statistically classified a large sample of nearby SNe Ia into those that are located in predominantly younger or older environments. This classification is based on the specific star formation rate measured within a projected distance of 1kpc from each SN location (LsSFR). This is an important refinement compared to using the local star formation rate directly, as it provides a normalization for relative numbers of available SN progenitors and is more robust against extinction by dust. We find that the SNe Ia in predominantly younger environments are {DELTA}Y=0.163+/-0.029mag (5.7{sigma}) fainter than those in predominantly older environments after conventional light-curve standardization. This is the strongest standardized SN Ia brightness systematic connected to the host-galaxy environment measured to date. The well-established step in standardized brightnesses between SNe Ia in hosts with lower or higher total stellar masses is smaller, at {DELTA}M=0.119+/-0.032mag (4.5{sigma}), for the same set of SNe Ia. When fit simultaneously, the environment-age offset remains very significant, with {DELTA}Y=0.129+/-0.032mag (4.0{sigma}), while the global stellar mass step is reduced to {DELTA}M=0.064+/-0.029mag (2.2{sigma}). Thus, approximately 70% of the variance from the stellar mass step is due to an underlying dependence on environment-based progenitor age. Also, we verify that using the local star formation rate alone is not as powerful as LsSFR at sorting SNe Ia into brighter and fainter subsets. Standardization that only uses the SNe Ia in younger environments reduces the total dispersion from 0.142+/-0.008mag to 0.120+/-0.010mag. We show that as environment-ages evolve with redshift, a strong bias, especially on the measurement of the derivative of the dark energy equation of state, can develop. Fortunately, data that measure and correct for this effect using our local specific star formation rate indicator, are likely to be available for many next-generation SN Ia cosmology experiments.
4297. Sample SNRs for M31 and M33
ID:
ivo://CDS.VizieR/J/ApJ/795/170
Title:
Sample SNRs for M31 and M33
Short Name:
J/ApJ/795/170
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using Hubble Space Telescope photometry to measure star formation histories, we age-date the stellar populations surrounding supernova remnants (SNRs) in M31 and M33. We then apply stellar evolution models to the ages to infer the corresponding masses for their supernova progenitor stars. We analyze 33 M33 SNR progenitors and 29 M31 SNR progenitors in this work. We then combine these measurements with 53 previously published M31 SNR progenitor measurements to bring our total number of progenitor mass estimates to 115. To quantify the mass distributions, we fit power laws of the form dN/dM{prop.to}M^-{alpha}^. Our new larger sample of M31 progenitors follows a distribution with {alpha}=4.4_-0.4_^+0.4^, and the M33 sample follows a distribution with {alpha}=3.8_-0.5_^+0.4^. Thus both samples are consistent within the uncertainties, and the full sample across both galaxies gives {alpha}=4.2_-0.3_^+0.3^. Both the individual and full distributions display a paucity of massive stars when compared to a Salpeter initial mass function, which we would expect to observe if all massive stars exploded as SN that leave behind observable SNR. If we instead fix {alpha}=2.35 and treat the maximum mass as a free parameter, we find M_max_~35-45 M_{sun}_, indicative of a potential maximum cutoff mass for SN production. Our results suggest that either SNR surveys are biased against finding objects in the youngest (<10 Myr old) regions, or the highest mass stars do not produce SNe.
4298. 4 samples of disc galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/467/2127
Title:
4 samples of disc galaxies
Short Name:
J/MNRAS/467/2127
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the influence of environment on the structure of disc galaxies, using IMFIT to measure the g- and r-band structural parameters of the surface-brightness profiles for ~700 low-redshift (z<0.063) cluster and field disc galaxies with intermediate stellar mass (0.8x10^10^M_{sun}_<M*<4x10^10^M_{sun}_) from the Sloan Digital Sky Survey, DR7. Based on this measurement, we assign each galaxy to a surface-brightness profile type (Type I = single-exponential, Type II = truncated, Type III = antitruncated). In addition, we measure (g-r) rest frame colour for disc regions separated by the break radius. Cluster disc galaxies (at the same stellar mass) have redder (g-r) colour by ~0.2 mag than field galaxies. This reddening is slightly more pronounced outside the break radius. Cluster disc galaxies also show larger global Sersic-indices and are more compact than field discs, both by ~15 per cent. This change is connected to a flattening of the (outer) surface-brightness profile of Type I and - more significantly - of Type III galaxies by ~8 per cent and ~16 per cent, respectively, in the cluster environment compared to the field. We find fractions of Type I, Type II and Type III of (6+/-2) per cent, (66+/-4) per cent and (29+/-4) per cent in the field and (15_-4_^+7^) per cent, (56+/-7) per cent and (29+/-7) per cent in the cluster environment, respectively. We suggest that the larger abundance of Type I galaxies in clusters (matched by a corresponding decrease in the Type II fraction) could be the signature of a transition between Type II and Type I galaxies produced/enhanced by environment-driven mechanisms.
4299. SAO and Supplementary Data
ID:
ivo://CDS.VizieR/V/15
Title:
SAO and Supplementary Data
Short Name:
V/15
Date:
21 Oct 2021
Publisher:
CDS
Description:
This SAO catalogue (Smithsonian Astrophysical Observatory Catalogue of 258,997 stars, 1966; see catalog <I/131>), connected to the CSI (Catalogue of Stellar Identifications, see Ochsenbein et al. 1981), enables researchers to retrieve reliable astrophysical data for about 20,000 stars. This includes SAO identifications, CSI identifications, equatorial coordinates (B1950), Galactic coordinates, proper motions, photometric data, spectral classifications, radial velocity, etc. The SAO/HD cross index for about 188,000 stars allows users to find (or enter) the catalog with the HD number of the star. The notes contain detected errors, the value of the trigonometric parallax taken from the Jenkins' (1952, 1963) catalogues, the double star designation ADS or IDS, and the name of the star.
4300. SARS galaxy luminosity profiles
ID:
ivo://CDS.VizieR/J/AJ/129/1237
Title:
SARS galaxy luminosity profiles
Short Name:
J/AJ/129/1237
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have analyzed CCD images of 14 Abell clusters in the R filter of the Southern Abell Clusters Redshifts Survey (SARS) with cz<40,000km/s. We have obtained the luminosity profiles for 507 galaxies, of which 232 (46%) have known redshifts. In order to fit the luminosity profiles, we used the de Vaucouleurs law for bulge systems and an exponential profile for disk systems, and we also fitted the Sersic's law (r^n^) to all galaxy profiles.