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1921. Light curves of RR Lyrae stars in M3 (NGC5272)
ID:
ivo://CDS.VizieR/J/ApJS/219/25
Title:
Light curves of RR Lyrae stars in M3 (NGC5272)
Short Name:
J/ApJS/219/25
Date:
21 Oct 2021
Publisher:
CDS
Description:
The overtone and multi-mode RR Lyrae stars in the globular cluster M3 are studied using a 200 day long, B,V, and l_c_ time-series photometry obtained in 2012. 70% of the 52 overtone variables observed show some kind of multi-periodicity (with additional frequency at f_0.61_=f_1O_/0.61 frequency ratio, Blazhko effect, double/multi-mode pulsation, and period doubling). A signal at the 0.587 frequency ratio to the fundamental-mode frequency is detected in the double-mode star, V13, which may be identified as the second radial overtone mode. If this mode identification is correct, then V13 is the first RR Lyrae star showing triple-mode pulsation of the first three radial modes. Either the Blazhko effect or the f_0,61_ frequency (or both of these phenomena) appears in seven double-mode stars. The P_1O_/P_F_ period ratio of RRd stars showing the Blazhko effect are anomalous. A displacement of the main frequency component at the fundamental mode with the value of modulation frequency (or its half), is detected in three Blazhko RRd stars that are parallel with the appearance of the overtone-mode pulsation. The f_0.61_ frequency appears in RRc stars that lie at the blue side of the double-mode region and in RRd stars, raising the suspicion that its occurrence may be connected to double-mode pulsation. The changes of the Blazhko and double-mode properties of the stars are also reviewed using the recent and archive photometric data.
1922. 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.
1923. Light curves of 2 Seyfert 1 galaxies
ID:
ivo://CDS.VizieR/J/ApJ/854/107
Title:
Light curves of 2 Seyfert 1 galaxies
Short Name:
J/ApJ/854/107
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present optical continuum lags for two Seyfert 1 galaxies, MCG+08-11-011 and NGC 2617, using monitoring data from a reverberation mapping campaign carried out in 2014. Our light curves span the ugriz filters over four months, with median cadences of 1.0 and 0.6 days for MCG+08-11-011 and NGC 2617, respectively, combined with roughly daily X-ray and near-UV data from Swift for NGC 2617. We find lags consistent with geometrically thin accretion-disk models that predict a lag-wavelength relation of {tau}{propto}{lambda}^4/3^. However, the observed lags are larger than predictions based on standard thin-disk theory by factors of 3.3 for MCG+08-11-011 and 2.3 for NGC 2617. These differences can be explained if the mass accretion rates are larger than inferred from the optical luminosity by a factor of 4.3 in MCG+08-11-011 and a factor of 1.3 in NGC 2617, although uncertainty in the SMBH masses determines the significance of this result. While the X-ray variability in NGC 2617 precedes the UV/optical variability, the long (2.6 day) lag is problematic for coronal reprocessing models.
1924. 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.
1925. 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.
1926. Light curves of the PMS eclipsing binary Par 1802
ID:
ivo://CDS.VizieR/J/ApJ/745/58
Title:
Light curves of the PMS eclipsing binary Par 1802
Short Name:
J/ApJ/745/58
Date:
21 Oct 2021
Publisher:
CDS
Description:
Parenago 1802, a member of the ~1 Myr Orion Nebula Cluster, is a double-lined, detached eclipsing binary in a 4.674 day orbit, with equal-mass components (M_2_/M_1_=0.985+/-0.029). Here we present extensive VI_C_JHK_S_light curves (LCs) spanning ~15 yr, as well as a Keck/High Resolution Echelle Spectrometer (HIRES) optical spectrum. The LCs evince a third light source that is variable with a period of 0.73 days, and is also manifested in the high-resolution spectrum, strongly indicating the presence of a third star in the system, probably a rapidly rotating Classical T Tauri star. We incorporate this third light into our radial velocity and LC modeling of the eclipsing pair, measuring accurate masses (M_1_=0.391+/-0.032 and M_2_=0.385+/-0.032M_{sun}_), radii (R_1_=1.73+/-0.02 and R_2_=1.62+/-0.02R_{sun}_), and temperature ratio (T_eff,1_/T_eff,2_=1.0924+/-0.0017). Thus, the radii of the eclipsing stars differ by 6.9%+/-0.8%, the temperatures differ by 9.2%+/-0.2%, and consequently the luminosities differ by 62%+/-3%, despite having masses equal to within 3%. This could be indicative of an age difference of ~3x10^5^yr between the two eclipsing stars, perhaps a vestige of the binary formation history. We find that the eclipsing pair is in an orbit that has not yet fully circularized, e=0.0166+/-0.003. In addition, we measure the rotation rate of the eclipsing stars to be 4.629+/-0.006 days; they rotate slightly faster than their 4.674 day orbit. The non-zero eccentricity and super-synchronous rotation suggest that the eclipsing pair should be tidally interacting, so we calculate the tidal history of the system according to different tidal evolution theories. We find that tidal heating effects can explain the observed luminosity difference of the eclipsing pair, providing an alternative to the previously suggested age difference.
1927. Light curves of the PMS system TY CrA
ID:
ivo://CDS.VizieR/J/A+AS/130/245
Title:
Light curves of the PMS system TY CrA
Short Name:
J/A+AS/130/245
Date:
21 Oct 2021
Publisher:
CDS
Description:
Complete uvby light curves of the detached Herbig Be eclipsing binary TY Coronae Australis are presented. A total of 1787 photometric measurements in each of the four colours were obtained in 1989 and in 1992-1994. A detailed analysis of the y light curve obtained in 1992-1993 is published separately (Casey et al. 1997). The reflection nebula around the system contributes about 30% of the light in all four passbands. Here we present and discuss the non-eclipse-related photometric variability of the system. We suggest that these variations are the result of variable obscuration, possibly linked to dust shells physically associated to the system.
1928. 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.
1929. Light curves of the triple system V906 Sco
ID:
ivo://CDS.VizieR/J/A+AS/125/471
Title:
Light curves of the triple system V906 Sco
Short Name:
J/A+AS/125/471
Date:
21 Oct 2021
Publisher:
CDS
Description:
Complete uvby light curves of the detached triple-lined late B-type eclipsing binary V906 Scorpii, obtained from 1987 to 1991, are presented. A detailed photometric analysis based on these observations and on new spectroscopic material yields accurate masses and radii (errors <2%) for the components, confirms that the system is member of NGC 6475 (Messier 7) and is published separately (Alencar et al., 1997A&A...326..709A)
1930. 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.