- ID:
- ivo://CDS.VizieR/J/A+AS/136/379
- Title:
- uvby photometry of 4 CP stars
- Short Name:
- J/A+AS/136/379
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Differential Stroemgren uvby photometric observations from the Four College Automated Photoelectric Telescope are presented for the magnetic CP stars 45 Leo, HR 4330, 49 Her, and HR 6718. We refined Winzer's periods for 45 Leo and HR 6718 to 1.443820 days and 0.51899days, respectively. For HR 4330 our period of 3.516 days is quite different from that of Winzer. That for 49 Her, 0.93663days, is an alias of Winzer's.
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- ID:
- ivo://CDS.VizieR/J/A+AS/136/111
- Title:
- uvby photometry of 4 CP stars
- Short Name:
- J/A+AS/136/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Differential Stroemgren uvby observations from the Four College Automated Photoelectric Telescope are presented for the mCP stars HD 35298, 19 Lyr, HD 192678, and HR 8216. The period for HD 35298 of 1.85457 days is a revision of North's value while that for 19 Lyr of 7.0980 days is alias of that found by Winzer. HD 192678 is found to be a small amplitude photometric variable with the 6.4186 day period proposed by Leroy from polarization measurements. For HR 8216, observations taken between 1995 and 1998 confirm that the star has remained constant at least since 1990.
- ID:
- ivo://CDS.VizieR/J/A+AS/122/249
- Title:
- uvby photometry of 4 CP stars
- Short Name:
- J/A+AS/122/249
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Differential Stroemgren uvby photometric observations from the Four College Automated Photoelectric Telescope refine the rotational periods and define the shapes of the light curves of four magnetic Chemically Peculiar stars. HD 32633 (P=6.43000d) exhibits an in-phase variability with asymmetrically shaped light curves. 25 Sex (P=4.37900d) has a complex variability with the v, b, and y light variability crudely in phase, but quite different from that of u. HR 7224 (P=1.123095d) shows in-phase variability with two nearly equal secondary minima. HD 200311 (P=26.0042d), which was previous thought to be a long period variable, is found to be a modest photometric variable.
- ID:
- ivo://CDS.VizieR/J/A+AS/146/13
- Title:
- uvby photometry of 4 CP stars
- Short Name:
- J/A+AS/146/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Differential Stroemgren uvby observations from the Four College Automated Photoelectric Telescope (FCAPT) are presented for the mCP stars 20 Eri, HR 1297, 12 CMa, and HD 134214. Adelman & Boyce found suggestions that the light curves of 20 Eri change between observing seasons. Observations for two additional seasons confirm this behavior and lead to an improved period of 1.928890 days. For HR 1297 a new period of 15.7490 days was derived. The uvby light curves now appear to be the same for different observing seasons. 12 CMa is found to be a photometric variable with the 2.18010 day period determined from magnetic measurements by Bohlender et al. Observations of the rapidly oscillating Ap star HD 134214 confirm the lack of photometric variability which is not associated with the rapid oscillations.
- ID:
- ivo://CDS.VizieR/J/A+AS/134/53
- Title:
- uvby photometry of 4 CP stars
- Short Name:
- J/A+AS/134/53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Differential Stroemgren uvby photometry obtained with the Four College Automated Photoelectric Telescope shows that the hot HgMn star 33 Gem is photometrically constant. The Si star HD 15980 is found to be a variable whose period is significantly greater than 2 years. The unusual magnetic chemically peculiar Co star HR 1094 is discovered to be a low amplitude photometric variable with the magnetic field period of Hill & Blake (1996MNRAS.278..183H), 2.9761 days. The ephemeris for the magnetic chemically peculiar star HD 115708 of Wade et al. (1996A&A...307..500W) is confirmed with the error in its period of 5.07622 days being greatly reduced. The u, v, b, and y light curves for both HR 1094 and HD 115708 exhibit differences which indicate complex elemental photospheric abundance distributions.
- ID:
- ivo://CDS.VizieR/J/A+AS/125/65
- Title:
- uvby photometry of 4 CP stars
- Short Name:
- J/A+AS/125/65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Differential Stroemgren uvby photometric observations from the Four College Automated Photoelectric Telescope are presented for four magnetic chemically peculiar stars. Comparison with uvby photometry of Pedersen & Thomsen for HD 37776 yields an improved period of 1.538675 days. New periods of 15.0305 days and 18.065 days are found for the sharp-lined stars HR 2258 and HR 6958, respectively, rather than one of their aliases. For HR 6958 each color shows a slightly different time of maximum. Comparison of the four color photometry of 108 Aqr taken during the fall of 1995 which well covers the period shows the presence of a secondary minimum near primary maximum in u, v, and b. Comparison with published photometry indicates indicates that subtle changes in the shapes of the light curves have occurred suggesting that this star might be precessing.
- ID:
- ivo://CDS.VizieR/J/A+A/390/1023
- Title:
- uvby photometry of 4 CP stars
- Short Name:
- J/A+A/390/1023
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Differential Stroemgren uvby observations from the Four College Automated Photoelectric Telescope (FCAPT) are presented for the CP stars HR 149 and HR 7911 and the mCP stars HD 32966 and HD 171782. The Hg-Mn star HR 149 is found to be constant while HR 7911 with a period of 5.9617 days probably has a component which is a magnetic CP star. Improved periods were derived for HD 32966 and HD 171782 of 3.0927 and 4.4674 days, respectively. The former is a rather large amplitude mCP star. Both have at least one light curve different in shape from the others observed.
- ID:
- ivo://CDS.VizieR/J/A+A/487/1081
- Title:
- uvby photometry of 6 eclipsing binaries
- Short Name:
- J/A+A/487/1081
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate mass, radius, and abundance determinations from binaries provide important information on stellar evolution, fundamental to central fields in modern astrophysics and cosmology. Within the long-term Copenhagen Binary Project, we aim to obtain high-quality light curves and standard photometry for double-lined detached eclipsing binaries with late A, F, and G type main-sequence components, needed for the determination of accurate absolute dimensions and abundances, and for detailed comparisons with results from recent stellar evolutionary models. Between March 1985 and July 2007, we carried out photometric observations of AD Boo, HW CMa, SW CMa, V636 Cen, VZ Hya, and WZ Oph at the Stromgren Automatic Telescope at ESO, La Silla. We obtained complete uvby light curves, ephemerides, and standard uvby{beta} indices for all six systems.
- ID:
- ivo://CDS.VizieR/J/A+AS/106/333
- Title:
- uvby photometry of four CP stars
- Short Name:
- J/A+AS/106/333
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Differential Stroemgren uvby photometric observations from the Four College Automated Photoelectric Telescope of four chemical peculiar stars is presented and analyzed. The peculiar Hg-Mn star {alpha} And is found not to be a photometric variable within the errors of measurement contrary to some published studies. Observations of the magnetic CP star HD 184905 were used to refine the zero epoch and the period which was found to be 1.85435 days. Our photometry and that of Morrison & Wolff are generally quite similar. We find evidence for two sub-minima within the broad minimum in both u and y. The cool magnetic CP star HR 8216 is non-variable in agreement with previous studies that suggested it was constant or a very long period variable. The CP star HR 8434 has a period of 1.43242 days and shows a generally in phase variation of u, v, b, and y. The light curves have two nearly equally maximum and a sharp minimum. The largest amplitude is for u, 0.085 mag.
- ID:
- ivo://CDS.VizieR/J/A+A/402/509
- Title:
- uvby photometry of four MC eclipsing binaries
- Short Name:
- J/A+A/402/509
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new accurate CCD uvby light curves for the LMC eclipsing binaries HV 982 and HV 12578, and for the SMC systems HV 1433 and HV 11284 obtained at the Danish 1.5m telescope at ESO, La Silla, equipped with a direct camera and CCD #28 (a thinned 1024x1024 Tek device), during several periods between November 1992 and November 1995. The light curves were derived from DoPHOT photometry, and typical accuracies are between 0.007 and 0.012mag per point. Standard uvby indices have also been established for each binary, primarily for determination of interstellar reddening and absorption. For HV 982 and HV 12578, accurate photometric elements have been established. Both systems consist of two detached components of comparable sizes in an eccentric orbit.
