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3641. Local SDSS galaxies in Herschel Stripe 82
ID:
ivo://CDS.VizieR/J/MNRAS/457/2703
Title:
Local SDSS galaxies in Herschel Stripe 82
Short Name:
J/MNRAS/457/2703
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study a set of 3319 galaxies in the redshift interval 0.04<z<0.15 Herschel/SPIRE 250{mu}m band. Total infrared (TIR) luminosities derived from HerS and Wide-field Infrared Survey Explorer (WISE) photometry allow us to compare infrared and optical estimates of SFR with unprecedented statistics for diverse classes of galaxies. We find excellent agreement between TIR-derived and emission line-based SFRs for H ii galaxies. Other classes, such as active galaxies and evolved galaxies, exhibit systematic discrepancies between optical and TIR SFRs. We demonstrate that these offsets are attributable primarily to survey biases and the large intrinsic uncertainties of the D_n_4000- and colour-based optical calibrations used to estimate the SDSS SFRs of these galaxies. Using a classification scheme which expands upon popular emission-line methods, we demonstrate that emission-line galaxies with uncertain classifications include a population of massive, dusty, metal-rich star-forming systems that are frequently neglected in existing studies. We also study the capabilities of infrared selection of star-forming galaxies. FIR selection reveals a substantial population of galaxies dominated by cold dust which are missed by the long-wavelength WISE bands. Our results demonstrate that Herschel large-area surveys offer the means to construct large, relatively complete samples of local star-forming galaxies with accurate estimates of SFR that can be used to study the interplay between nuclear activity and star formation.
3642. Local Star Formation effects on type Ia SNe
ID:
ivo://CDS.VizieR/J/ApJ/812/31
Title:
Local Star Formation effects on type Ia SNe
Short Name:
J/ApJ/812/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
Recent studies found a correlation with ~3{sigma} significance between the local star formation measured by GALEX in SN Ia host galaxies and the distances or dispersions derived from these SNe. We search for these effects by using data from recent cosmological analyses to greatly increase the SN Ia sample; we include 179 GALEX-imaged SN Ia hosts with distances from the Joint Light-curve Analysis (JLA) and Pan-STARRS SN Ia cosmology samples and 157 GALEX-imaged SN Ia hosts with distances from the Riess et al. (2011, J/ApJ/730/119) H_0_ measurement. We find little evidence that SNe Ia in locally star-forming environments are fainter after light curve correction than SNe Ia in locally passive environments. We find a difference of 0.000+/-0.018 (stat+sys) mag for SNe fit with SALT2 and 0.029+/-0.027 (stat+sys) mag for SNe fit with MLCS2k2 (R_V_=2.5), which suggests that proposed changes to recent measurements of H_0_ and w are not significant and numerically smaller than the parameter measurement uncertainties. We measure systematic uncertainties of ~0.01-0.02mag by performing several plausible variants of our analysis. We find the greatly reduced significance of these distance modulus differences compared to Rigault et al. (2013A&A...560A..66R) results from two improvements with fairly equal effects, our larger sample size and the use of the JLA and Riess et al. sample selection criteria. Without these improvements, we recover the results of Rigault et al. We find that both populations have similar dispersions in distance than found by Rigault et al. and Kelly et al. (2015Sci...347.1459K), with slightly smaller dispersions for locally passive (log({Sigma}_SFR_)<-2.9dex) SNe Ia fit with MLCS, the opposite of the effect seen by Rigault et al. and Kelly et al. We caution that measuring the local environments of SNe Ia in the future may require a higher resolution instrument than GALEX and that SN Ia sample selection has a significant effect on local star formation biases.
3643. LONEOS-I RR Lyrae stars
ID:
ivo://CDS.VizieR/J/ApJ/678/865
Title:
LONEOS-I RR Lyrae stars
Short Name:
J/ApJ/678/865
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present 838 ab-type RR Lyrae stars from the Lowell Observatory Near Earth Objects Survey Phase I (LONEOS-I). These objects cover 1430deg^2^ and span distances ranging from 3 to 30kpc from the Galactic center. Object selection is based on phased, photometric data with 28-50 epochs. We use this large sample to explore the bulk properties of the stellar halo, including the spatial distribution. The period-amplitude distribution of this sample shows that the majority of these RR Lyrae stars resemble Oosterhoff type I, but there is a significant fraction (26%) which have longer periods and appear to be Oosterhoff type II. We find that the radial distributions of these two populations have significantly different profiles ({rho}_OoI_~R^-2.26+/-0.07^ and {rho}_OoII_~R^-2.88+/-0.11^). This suggests that the stellar halo was formed by at least two distinct accretion processes and supports dual-halo models.
3644. Long-period variables in NGC 147 and NGC 185
ID:
ivo://CDS.VizieR/J/A+A/532/A78
Title:
Long-period variables in NGC 147 and NGC 185
Short Name:
J/A+A/532/A78
Date:
21 Oct 2021
Publisher:
CDS
Description:
Previous studies on the stellar content of the two nearby dwarf galaxies NGC 147 and NGC 185 reveal a rich population of late-type giants in both systems, including a large number of carbon-rich objects. These stars are known to show pronounced photometric variability, which can be used for a more detailed characterisation of these highly evolved stars. Owing to their well-studied parameters, these Local Group members are ideal candidates for comparative studies. Through photometric monitoring, we attempt to provide a catalogue of long-period variables (LPVs), including Mira variables, semi-regular variables, and even irregular variables in NGC 147 and NGC 185. We investigate the light variations and compare the characteristics of these two LPV populations with the results found for other galaxies, such as the LMC.
3645. Long period variables in omega Cen
ID:
ivo://CDS.VizieR/J/A+A/585/A111
Title:
Long period variables in omega Cen
Short Name:
J/A+A/585/A111
Date:
21 Oct 2021
Publisher:
CDS
Description:
Recent studies have detected multiple populations in globular clusters. The massive globular cluster {omega} Cen hosts at least three populations of different metallicity. The most metal-rich one is thought to show also an overabundance of He. These differences should become visible in the structure, evolution, and pulsation of its stars. We aim to study the effects of the different starting compositions of the three populations in {omega} Cen on the most luminous red giants in this cluster. The long-periodic variability of evolved stars in {omega} Cen opens a comparably easy access window to the structure and composition of these objects. We made a detailed search for long-period variables (LPVs) in {omega} Cen leading to the detection of many new variables and period determinations for a significant number of them. Periods and luminosities were then compared with the most recent pulsation models for these kinds of stars.
3646. Long-term BVRI photometry of 15 PMS stars
ID:
ivo://CDS.VizieR/J/other/RAA/18.137
Title:
Long-term BVRI photometry of 15 PMS stars
Short Name:
J/other/RAA/18.1
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper reports results from the multicolor photometric observations of 15 pre-main sequence stars collected in the period September 2010 - October 2017. The stars from our study are located in the star-forming HII region IC 5070. These objects were previously detected as either emission line stars, flare stars, T Tauri variables or Herbig Ae/Be stars. Photometric observations, especially concerning the long-term behavior of the objects, are missing in the literature. We present the first photometric monitoring for all stars from our study. The analysis of the obtained BVRI photometric data allows us to draw the conclusion that all investigated objects are variable stars. In the case of LkHa 146, we identified previously unknown periodicity in its photometric variability.
3647. Long-term BVRI photometry of V1704 Cygni
ID:
ivo://CDS.VizieR/J/other/BAJ/29.10
Title:
Long-term BVRI photometry of V1704 Cygni
Short Name:
J/other/BAJ/29.1
Date:
22 Feb 2022
Publisher:
CDS
Description:
Results from BVRI photometric observations of the pre-main sequence star V1704 Cyg collected during the time period from August 2010 to December 2017 are presented. The star is located in the star-forming HII region IC 5070 and it exhibits photometric variability in all optical passbands. After analysing the obtained data, V1704 Cyg is classified as a classical T Tauri star.
3648. Long-term BVRI photometry of V2492 Cygni
ID:
ivo://CDS.VizieR/J/other/PASA/35.7
Title:
Long-term BVRI photometry of V2492 Cygni
Short Name:
J/other/PASA/35.
Date:
21 Oct 2021
Publisher:
CDS
Description:
Results from BVRI photometric observations of the young stellar object V2492 Cyg collected during the period from August 2010 to December 2017 are presented. The star is located in the field of the Pelican Nebula and it was discovered in 2010 due to its remarkable increase in the brightness by more than 5mag in R-band. According to the first hypothesis of the variability, V2492 Cyg is an FUor candidate. During subsequent observations, it was reported that the star shows the characteristics inherent to EXor- and UXor-type variables. The optical data show that during the whole time of observations the star exhibits multiple large amplitude increases and drops in the brightness. In the beginning of 2017, we registered a significant increase in the optical brightness of V2492 Cyg, which seriously exceeds the maximal magnitudes registered after 2010.
3649. Long-term BVRI photometry of V900 Mon
ID:
ivo://CDS.VizieR/J/other/Ser/202.31
Title:
Long-term BVRI photometry of V900 Mon
Short Name:
J/other/Ser/202.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from photometric monitoring of V900 Mon, one of the newly discovered and still under-studied object from the FU Orionis type. The FUor phenomenon is very rarely observed, but it is essential for stellar evolution. Since we only know about twenty stars of this type, the study of each new object is very important for our knowledge. Our data were obtained in optical spectral region with the BVRI Johnson-Cousins set of filters during the period from September 2011 to April 2021. In order to follow the photometric history of the object, we measured its stellar magnitudes on available plates from the Mikulski Archive for Space Telescopes. The collected archival data suggest that the rise in brightness of V900 Mon began after January 1989 and the outburst goes on so far. In November 2009, when the outburst was registered, the star had already reached the level of brightness close to the current one. Our observations indicate that during the period 2011-2017 the stellar magnitude increased gradually in each pass band. The observed amplitude of the ourburst is about 4 magnitudes (R). During the last three years, the increase in brightness has stopped and there has even been a slight decline. The comparison of light curves of the known FUor objects shows that they are very diverse and are rarely repeated. However, the photometric data we have so far show that V900 Mon's light curve is somewhat similar to those of V1515 Cyg and V733 Cep.
3650. Long-term CCD photometry of the EB 2M1533+3759
ID:
ivo://CDS.VizieR/J/ApJ/839/39
Title:
Long-term CCD photometry of the EB 2M1533+3759
Short Name:
J/ApJ/839/39
Date:
21 Oct 2021
Publisher:
CDS
Description:
New CCD photometry of seven successive years from 2010 is presented for the HW Vir-type eclipsing binary 2M 1533+3759. Using the VI light curves together with the radial-velocity data given by For+ (2010ApJ...708..253F), we determined the absolute parameters of each component to be M1=0.442+/-0.012M{sun}, M2=0.124+/-0.005M{sun}, R1=0.172+/-0.002R{sun}, R2=0.157+/-0.002R{sun}, L1=19.4+/-1.4L{sun}, and L2=0.002+/-0.002L{sun}. These indicate that 2M 1533+3759 is a detached system consisting of a normal sdB primary and an M7 dwarf companion. Detailed analyses of 377 minimum epochs, including our 111 timings, showed that the orbital period of the system remains constant during the past 12 years. Inspecting both types of minima, we found a delay of 3.9+/-1.0s in the arrival times of the secondary eclipses relative to the primary eclipse times. This delay is in satisfactory agreement with the predicted Romer delay of 2.7+/-1.4s, and the result is the second measurement in sdB+M eclipsing binaries. The time shift of the secondary eclipse can be explained by some combination of the Romer delay and a non-zero eccentricity. Then the binary star would have a very small eccentricity of e.cos{omega}~0.0001.