Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/419/2173
- Title:
- Long-term photometry of M3 RR Lyrae
- Short Name:
- J/MNRAS/419/2173
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The period-change behaviour of 134 RR Lyrae stars in the globular cluster Messier 3 (M3) is investigated on the ~120yr time-base of the photometric observations. The mean period-change rates ({beta}~~0.01d/Myr) of the subsamples of variables exhibiting the most regular behaviour are in good agreement with theoretical expectations based on horizontal branch stellar evolution models. However, a large fraction of variables show period changes that contradict the evolutionary expectations.
- ID:
- ivo://CDS.VizieR/J/A+A/568/A49
- Title:
- Long-term photometry of pre-MS stars
- Short Name:
- J/A+A/568/A49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To broaden the search and study stars in the early evolutionary phase, we investigated a sample of 17 pre-main sequence objects previously detected as either H{alpha} emission-line pre-main sequence stars or T Tauri variables located in the field of the North America/Pelican Nebula complex. Johnson-Cousins B, V, Rc, Ic magnitudes and mean color indices for the program stars are determined from more than 12400 measurements from archive photographic plates and from CCD data collected at 7 observatories covering the period of almost 60 years from 1954 up to 2013. We complemented previously rare insights on the photometry of the program stars and presented their photometric history, which for almost all program stars is the first long term photometric monitoring on a timescale of 6 decades. Eight program stars are found to be classical T Tauri stars of variability type II, while 6 program stars are weak-line T Tauri stars of variability type I. For the first time, periodicity is found for three stars: V1716 Cyg indicates a 4.15 day period, V2051 Cyg indicates a 384 day period, and V521 Cyg a period of 503 days.
- ID:
- ivo://CDS.VizieR/J/other/JAD/18.5
- Title:
- Long-term photometry of 11 RS CVn stars
- Short Name:
- J/other/JAD/18.5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- I present BVRI photometry of short-period (P<1d) eclipsing RS CVn binary star systems collected between 1988 and 2009 at Mount Laguna Observatory. Most of the data are for ER Vul and WY Cnc, with light curves nearly every year during that time period. I also present light curves for at least several years for XY UMa, BH Vir, CG Cyg, RT And, and UV Psc. I have fewer light curves for SV Cam, UV Leo, 1E1919+0427, and GSC 2038-0293. In addition to the eclipsing short-period systems, I also include UBVRI data for two longer period non-eclipsing RS CVn binary systems: UZ Lib and DM UMa, as well as two active chromosphere single stars: FK Com and HD 199178.
- ID:
- ivo://CDS.VizieR/II/170
- Title:
- Long-term photometry of Variables I.
- Short Name:
- II/170
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the first catalogue of photometric data in the Stroemgren system obtained during the period October 1982 - September 1986. Full description can be found in ESO report SP 8. Since our goal is not absolute (all-sky) photometry, the observations should be used for differential photometry only. The mean values of the r.m.s. deviations of the differential measurements of comparison stars are around (from Table 5 of paper) ------------------------------------ System y b-y m1 c1 ------------------------------------ 1 0.0109 0.0088 0.0133 0.0136 4 0.0068 0.0057 0.0079 0.0118 5 0.0087 0.0070 0.0114 0.0114 6 0.0090 0.0078 0.0126 0.0132 7 0.0071 0.0033 0.0041 0.0065 ------------------------------------
- ID:
- ivo://CDS.VizieR/II/188
- Title:
- Long-term photometry of Variables II
- Short Name:
- II/188
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The second catalogue of the LTPV programme contains photometric data obtained during the period October 1986 - September 1990. Full description can be found in ESO reports SP 8 and 12. The data presented here have been upgraded since the printing of catalogue ESO SR 12; a major change is the use of a quite different standard, namely the ESO SAT (Stroemgren Automatic Telescope) instrumental system has been used as standard. The instrumental systems 6 and 8 can be obtained by applying the following color matrices (see ESO SR 12, page 4, Eq. (3)), inverted (b-y , y , m1 , c1): SYSTEM 6 1.0518 0.0000 0.0000 0.0000 0.0094 1.0000 0.0000 0.0000 -0.1238 0.0000 1.1206 0.0000 0.0426 0.0000 0.0000 1.0352 SYSTEM 8 1.0476 0.0000 0.0000 0.0000 0.0384 1.0000 0.0000 0.0000 -0.0877 0.0000 1.0487 0.0000 -0.2657 0.0000 0.0000 0.9732 It also very easy to go back to the same standard as in ESO SR 8 by applying the transformations given in Table 3 of ESO SR 12 (page 3). Note that the faint star C7060 is not identified so far. The mean values of the r.m.s. deviations of the differential measurements of comparison stars are around (from Table 5 of paper) ------------------------------------ System y b-y m1 c1 ------------------------------------ 6 0.0069 0.0058 0.0122 0.0129 7 0.0064 0.0030 0.0039 0.0067 8 0.0068 0.0061 0.0110 0.0097 ------------------------------------
- ID:
- ivo://CDS.VizieR/II/200
- Title:
- Long-term photometry of Variables III
- Short Name:
- II/200
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the third catalogue of photometric data in the Stroemgren system obtained during the period October 1990-January 1992 in the framework of the Long-Term Photometry of Variables (LTPV) program at the European Southern Observatory. All data have been obtained with the Danish 50-cm telescope. The mean values of the r.m.s. deviations of the differential measurements of comparison stars are around (from Table 4 of paper) ------------------------------ y b-y m1 c1 ------------------------------ 0.005 0.002 0.004 0.006 ------------------------------
- ID:
- ivo://CDS.VizieR/II/202
- Title:
- Long-term photometry of Variables IV
- Short Name:
- II/202
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the fourth catalogue of photometric data in the Stroemgren system obtained during the period June 18, 1992 - August 23, 1994 in the framework of the Long-Term Photometry of Variables (LTPV) program at the European Southern Observatory. Since our goal is not absolute (all-sky) photometry, the observations should be used for differential photometry only. The mean values of the r.m.s. deviations of the differential measurements of comparison stars are around (from Table 3 of paper) ------------------------------ y b-y m1 c1 ------------------------------ 0.005 0.002 0.004 0.007 ------------------------------
- ID:
- ivo://CDS.VizieR/J/other/PASA/32.11
- Title:
- Long-term UBVRI photometry of GM Cep
- Short Name:
- J/other/PASA/32.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results from UBVRI photometric observations of the pre-main sequence star GM Cephei obtained in the period April 2011 - August 2014 are reported in the paper. Presented data are a continuation of our photometric monitoring of the star started in 2008. GM Cep is located in the field of the young open cluster Trumpler 37 and over the past years it has been an object of intense photometric and spectral studies. The star shows a strong photometric variability interpreted as a possible outburst from EXor type in previous studies. Our photometric data for a period of over six years show a large amplitude variability ({Delta}V~2.3mag) and several deep minimums in brightness are observed. The analysis of the collected multicolor photometric data show the typical of UX Ori variables a colour reversal during the minimums in brightness. The observed decreases in brightness have a different shape, and evidences of periodicity are not detected. At the same time, high amplitude rapid variations in brightness typical for the classical T Tauri stars also present on the light curve of GM Cep. The spectrum of GM Cep shows the typical of classical T Tauri stars wide H alpha emission line and absorption lines of some metals. We calculate the outer radius of the H{alpha} emitting region as 10.4+/-0.5R_{sun}_ and the accretion rate as 1.8x10^-7^M_{sun}_/yr.
- ID:
- ivo://CDS.VizieR/J/AJ/123/3460
- Title:
- Low-amplitude variables in NGC 6791
- Short Name:
- J/AJ/123/3460
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have undertaken a long-term project, the Planets in Stellar Clusters Extensive Search (PISCES), to search for transiting planets in open clusters. As our first target, we have chosen NGC 6791, a very old, populous, metal-rich cluster. We present the results of a test observing run at the F.L. Whipple Observatory's 1.2 m telescope, from 2001 July 6 to August 1. Our primary goal is to demonstrate the feasibility of obtaining the accuracy required for planetary-transit detection using image subtraction photometry on data collected with a 1 m class telescope. We present a catalog of 62 variable stars, 47 of them newly discovered, most with low-amplitude variability. Among those there are several BY Draconis type variables. We have also observed outbursts in the cataclysmic variables B7 and B8.