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1391. Light curves of RR Lyrae variables in M31
ID:
ivo://CDS.VizieR/J/MNRAS/478/4590
Title:
Light curves of RR Lyrae variables in M31
Short Name:
J/MNRAS/478/4590
Date:
10 Dec 2021 13:45:59
Publisher:
CDS
Description:
We present an analysis of M31 RR Lyrae stars in six different fields using archival imaging from the Hubble Space Telescope. Published data for M31, M33, and several M31 dwarf spheroidal galaxies are also used to study the global properties of RR Lyrae in these systems. From the properties of RR Lyrae stars, we found that the majority of M31 and M33 RRLs are of Oosterhoff I (OoI),while those in M31 dSphs are of Oosterhoff intermediate. The main parameter affecting these Oosterhoff types is likely to be metallicity. Metallicity also plays a role in the lack of RRLs in the high amplitude short period(HASP, defined as those with P<=0.48 and A_V_>=0.75mag) variables in M31 dSphs. This difference in the properties of RRLs between their parent galaxy and satellites, as well as the lack of RRLs in the HASP region in dSphs can also be observed in the Milky Way (MW). Therefore, systems like these dSphs are unlikely to be the main building blocks of the M31 and MW halo.
1392. Light Curves of 29 SNe
ID:
ivo://CDS.VizieR/J/AJ/112/2408
Title:
Light Curves of 29 SNe
Short Name:
J/AJ/112/2408
Date:
21 Oct 2021
Publisher:
CDS
Description:
BV(RI)_KC_ (see Bessel, 1990PASP..102.1181B) light curves are presented for 27 type Ia supernovae discovered during the course of the Calan/Tololo Survey and for two other SNe Ia observed during the same period. Estimates of the maximum light magnitudes in the B, V, and I bands and the initial decline rate parameter {Delta}m_15_(B) are also given.
1393. Light curves of 5 supernovae
ID:
ivo://CDS.VizieR/J/A+A/643/A35
Title:
Light curves of 5 supernovae
Short Name:
J/A+A/643/A35
Date:
21 Oct 2021
Publisher:
CDS
Description:
Rapid variability before and near the maximum brightness of supernovae has the potential to provide a better understanding of nearly every aspect of supernovae, from the physics of the explosion up to their progenitors and the circumstellar environment. Thanks to modern time-domain optical surveys, which are discovering supernovae in the early stage of their evolution, we have the unique opportunity to capture their intraday behavior before maximum. We present high-cadence photometric monitoring (on the order of seconds-minutes) of the optical light curves of three Type Ia and two Type II SNe over several nights before and near maximum light, using the fast imagers available on the 2.3m Aristarchos telescope at Helmos Observatory and the 1.2m telescope at Kryoneri Observatory in Greece. We applied differential aperture photometry techniques using optimal apertures and we present reconstructed light curves after implementing a seeing correction and the Trend Filtering Algorithm (TFA, Kovacs et al. 2005MNRAS.356..557K). TFA yielded the best results, achieving a typical precision between 0.01 and 0.04mag. We did not detect significant bumps with amplitudes greater than 0.05mag in any of the SNe targets in the VR-, R-, and I- bands light curves obtained. We measured the intraday slope for each light curve, which ranges between -0.37-0.36mag/d in broadband VR, -0.19-0.31mag/d in R band, and -0.13-0.10mag/d in I band. We used SNe light curve fitting templates for SN 2018gv, SN 2018hgc and SN 2018hhn to photometrically classify the light curves and to calculate the time of maximum. We provide values for the maximum of SN 2018zd after applying a low-order polynomial fit and SN 2018hhn for the first time. We conclude that optimal aperture photometry in combination with TFA provides the highest-precision light curves for SNe that are relatively well separated from the centers of their host galaxies. This work aims to inspire the use of ground-based, high-cadence and high-precision photometry to study SNe with the purpose of revealing clues and properties of the explosion environment of both core-collapse and Type Ia supernovae, the explosion mechanisms, binary star interaction and progenitor channels. We suggest monitoring early supernovae light curves in hotter (bluer) bands with a cadence of hours as a promising way of investigating the post-explosion photometric behavior of the progenitor stars.
1394. Light curves of the RR Lyr SDSS J015450.17+001500.7
ID:
ivo://CDS.VizieR/J/ApJ/780/92
Title:
Light curves of the RR Lyr SDSS J015450.17+001500.7
Short Name:
J/ApJ/780/92
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present and discuss an extensive data set for the non-Blazhko ab-type RR Lyrae star SDSS J015450+001501, including optical Sloan Digital Sky Survey ugriz light curves and spectroscopic data, LINEAR and Catalina Sky Survey unfiltered optical light curves, and infrared Two Micron All Sky Survey (2MASS) JHKs and Wide-field Infrared Survey Explorer W1 and W2 light curves. Most notable is that light curves obtained by 2MASS include close to 9000 photometric measures collected over 3.3yr and provide an exceedingly precise view of near-infrared variability. These data demonstrate that static atmosphere models are insufficient to explain multiband photometric light-curve behavior and present strong constraints for nonlinear pulsation models for RR Lyrae stars. It is a challenge to modelers to produce theoretical light curves that can explain data presented here, which we make publicly available.
1395. Light curves of type Ia supernovae (CfA3)
ID:
ivo://CDS.VizieR/J/ApJ/700/331
Title:
Light curves of type Ia supernovae (CfA3)
Short Name:
J/ApJ/700/331
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present multiband photometry of 185 type-Ia supernovae (SNe Ia), with over 11500 observations. These were acquired between 2001 and 2008 at the F. L. Whipple Observatory of the Harvard-Smithsonian Center for Astrophysics (CfA). This sample contains the largest number of homogeneously observed and reduced nearby SNe Ia (z<~0.08) published to date. It more than doubles the nearby sample, bringing SN Ia cosmology to the point where systematic uncertainties dominate. Our natural system photometry has a precision of <~0.02mag in BVRIr'i' and <~0.04 mag in U for points brighter than 17.5mag. We also estimate a systematic uncertainty of 0.03mag in our SN Ia standard system BVRIr'i' photometry and 0.07mag for U. Comparisons of our standard system photometry with published SN Ia light curves and comparison stars, where available for the same SN, reveal agreement at the level of a few hundredths mag in most cases. We find that 1991bg-like SNe Ia are sufficiently distinct from other SNe Ia in their color and light-curve-shape/luminosity relation that they should be treated separately in light-curve/distance fitter training samples.
1396. Light curves of type Ia supernovae in SNLS
ID:
ivo://CDS.VizieR/J/A+A/523/A7
Title:
Light curves of type Ia supernovae in SNLS
Short Name:
J/A+A/523/A7
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present photometric properties and distance measurements of 252 high redshift Type Ia supernovae (0.15<z<1.1) discovered during the first three years of the Supernova Legacy Survey (SNLS). These events were detected and their multi-colour light curves measured using the MegaPrime/MegaCam instrument at the Canada-France-Hawaii Telescope (CFHT), by repeatedly imaging four one-square degree fields in four bands. Follow-up spectroscopy was performed at the VLT, Gemini and Keck telescopes to confirm the nature of the supernovae and to measure their redshifts.
1397. Light curves of 5 type IIn supernovae
ID:
ivo://CDS.VizieR/J/A+A/555/A10
Title:
Light curves of 5 type IIn supernovae
Short Name:
J/A+A/555/A10
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present optical (uBgVri) and near-infrared (YJHKs) photometry of Type IIn Supernovae 2005kj, 2006aa, 2006bo, 2006qq, 2008fq, obtained by the Carnege Supernova Project. We also report the magnitudes of the local sequence stars for each of the five supernovae.
1398. Light curve templates of RR Lyrae stars
ID:
ivo://CDS.VizieR/J/ApJ/708/717
Title:
Light curve templates of RR Lyrae stars
Short Name:
J/ApJ/708/717
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an improved analysis of halo substructure traced by RR Lyrae stars in the Sloan Digital Sky Survey (SDSS) stripe 82 region. With the addition of SDSS-II data, a revised selection method based on new ugriz light curve templates results in a sample of 483 RR Lyrae stars that is essentially free of contamination. The main result from our first study persists: the spatial distribution of halo stars at galactocentric distances 5-100kpc is highly inhomogeneous. At least 20% of halo stars within 30kpc from the Galactic center can be statistically associated with substructure. We present strong direct evidence, based on both RR Lyrae stars and main-sequence stars, that the halo stellar number density profile significantly steepens beyond a Galactocentric distance of ~30kpc, and a larger fraction of the stars are associated with substructure. By using a novel method that simultaneously combines data for RR Lyrae and main-sequence stars, and using photometric metallicity estimates for main-sequence stars derived from deep co-added u-band data, we measure the metallicity of the Sagittarius dSph tidal stream (trailing arm) toward RA~2h-3h and DE~0{deg} to be 0.3dex higher ([Fe/H]=-1.2) than that of surrounding halo field stars.
1399. Light curve templates of SNe Ib/c from SDSS
ID:
ivo://CDS.VizieR/J/A+A/574/A60
Title:
Light curve templates of SNe Ib/c from SDSS
Short Name:
J/A+A/574/A60
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present optical (ugriz) light curve templates of supernovae Ib/c from the SDSS II SN survey.
1400. Light element abundances of RGB & AGB stars in M10
ID:
ivo://CDS.VizieR/J/AJ/156/6
Title:
Light element abundances of RGB & AGB stars in M10
Short Name:
J/AJ/156/6
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present CN and CH band measurements for 137 red giant branch (RGB) and asymptotic giant branch (AGB) stars in the Galactic globular cluster M10. Our measurements come from low-resolution spectroscopy taken with the Hydra spectrograph on the WIYN-3.5 m telescope. We use these measurements to identify two populations of stars within the cluster, CN-normal and CN-enhanced, and find that in our sample 60% of stars are CN-enhanced. Our large sample allows us to conduct a detailed analysis on the carbon and nitrogen abundances and the radial distribution of each population separately. Our analysis of the radial dependence shows that each population has the same radial distribution in the cluster, which is likely due to the cluster being dynamically evolved. We also compare our results to other methods of classifying multiple populations in globular clusters such as the Na-O anti-correlation and the HST pseudo-color-magnitude diagrams. We find that these three methods of identifying multiple populations are in good agreement with each other for M10 and all lead to an estimate of the fraction of second-generation stars approximately equal to 60%. Among AGB stars, when classified by the CN band, there appears to be a lack of second-generation stars when compared to the RGB stars. However, when classified by [N/Fe], we find a similar 60% of AGB stars in the second generation. Finally, we use the measured carbon and nitrogen abundances in RGB stars to study the change of each element with magnitude as stars evolve up the RGB, comparing the results to globular clusters of similar metallicity, M3 and M13.