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- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- ID:
- ivo://CDS.VizieR/J/AZh/88/34
- Title:
- Long-term (1984-2008) JHKLM photometry of stars
- Short Name:
- J/AZh/88/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Long-term (1984-2008) JHKLM photometry for 254 objects is presented. The observations were carried out in the standard JHKLM photometric system using an original method and a modern IR photometer designed and built at the Sternberg Astronomical Institute. Our program of studies included searches for and studies of relatively hot circumstellar dust envelopes.
- ID:
- ivo://CDS.VizieR/J/A+AS/131/321
- Title:
- Long-term monitoring of active stars. VIII.
- Short Name:
- J/A+AS/131/321
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As a part of an extensive program focusing on the global properties and evolution of active stars, high-precision UBV(RI)c photometry of 31 selected stars, collected at the European Southern Observatory over the 14-29 February 1992 interval, is presented. Significant evolution of the light curves, period variations and evidence for long-term variability of the global degree of spottedness are found. Some spectral classifications are revised and the inferred photometric parallaxes are compared, whenever possible, with the values measured by the Hipparcos satellite. Flare events were detected for the star HD 16157=CC Eri, EXO 055609-3804.4=TY Col and HD 119285=V851 Cen. Optical variability was discovered for the Pop II binary HD 89499. These observations contribute to the establishment of a time-extended photometric database which can give important clues on topics such as the stability of spotted areas, differential rotation, solar-like cycles and the correlation between inhomogeneities at different atmospheric levels.
- ID:
- ivo://CDS.VizieR/J/PAZh/41/303
- Title:
- Long-term monitoring of SZ Cam
- Short Name:
- J/PAZh/41/303
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of the reduction of our photometric and spectroscopic observations for the eclipsing binary SZ Cam performed with the telescopes at the Astronomical Observatory of the Ural Federal University and the Special Astrophysical Observatory of the Russian Academy of Sciences in 1996-2014. Based on an 11-year-long photometric monitoring of SZ Cam, we have obtained new elements of its photometric orbit and parameters of its components. We have detected low-amplitude periodic light variations in SZ Cam that are possibly related to the ellipsoidal shape of the components of the spectroscopic binary third body.
