- ID:
- ivo://CDS.VizieR/J/A+A/454/171
- Title:
- CCD {Delta}a-photometry of 8 open clusters
- Short Name:
- J/A+A/454/171
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The detection of magnetic chemically peculiar (CP2) stars in open clusters of the Milky Way can be used to study the influence of different galactic environments on the (non-)presence of peculiarities, which has to be taken into account in stellar evolution models. Furthermore it is still unknown if the CP2 phenomenon evolves, i.e. does the strength of the peculiarity feature at 5200{AA} increase or decrease with age. Methods. We have observed eight young to intermediate age open clusters in the {Delta}a photometric system.
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- ID:
- ivo://CDS.VizieR/J/AJ/141/21
- Title:
- CCD distance estimates of SCR targets
- Short Name:
- J/AJ/141/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD photometric distance estimates of 100 SCR (SuperCOSMOS RECONS) systems with {mu}>=0.18"/yr, 29 of which are new discoveries previously unpublished in this series of papers. These distances are estimated using a combination of new VRI photometry acquired at CTIO and JHK magnitudes extracted from 2MASS. The estimates are improvements over those determined using photographic plate BRI magnitudes from SuperCOSMOS plus JHK, as presented in the original discovery papers. In total, 77 of the 100 systems investigated are predicted to be within 25pc.
- ID:
- ivo://CDS.VizieR/J/A+A/414/23
- Title:
- CCD H{alpha} and R photometry of 334 galaxies
- Short Name:
- J/A+A/414/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We discuss the selection and observations of a large sample of nearby galaxies, which we are using to quantify the star formation activity in the local Universe. The sample consists of 334 galaxies across all Hubble types from S0/a to Im and with recession velocities of between 0 and 3000km/s. The basic data for each galaxy are narrow band H{alpha}+[NII] and R-band imaging, from which we derive star formation rates, H{alpha}+[NII] equivalent widths and surface brightnesses, and R-band total magnitudes. A strong correlation is found between total star formation rate and Hubble type, with the strongest star formation in isolated galaxies occurring in Sc and Sbc types. More surprisingly, no significant trend is found between H{alpha}+[NII] equivalent width and galaxy R-band luminosity. More detailed analyses of the data set presented here will be described in subsequent papers.
- ID:
- ivo://CDS.VizieR/J/AJ/156/134
- Title:
- CCD measurements of multiple stars at ASV & NAOR
- Short Name:
- J/AJ/156/134
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of classical CCD observations for 371 double or multiple stars (450 pairs) obtained at both, Serbian Astronomical Station on the mountain of Vidojevica (ASV) and Bulgarian National Astronomical Observatory at Rozhen (NAOR) are presented. At ASV the observations were performed with the 0.6 m telescope in the first half of 2016 during 11 nights, and with the newly mounted 1.4 m telescope in the second half of 2016 during 16 nights. At NAOR, the observations were performed with the 2 m telescope during four nights. In this paper, we present 477 measurements (position angle and angular separation) for these 450 pairs. Among them there are 41 pairs with published orbital or linear elements and residuals are given for them. Some pairs have measurements for several epochs. Our observed pairs have angular separations in the interval from 1.60" to 190.30", with a mean angular separation of 14.87" and a median value of 4.34". Two new pairs and linear elements for four pairs which are calculated for the first time are also presented.
- ID:
- ivo://CDS.VizieR/J/AJ/146/52
- Title:
- CCD measurements of multiple stars at NAOR and ASV
- Short Name:
- J/AJ/146/52
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the 2m telescope of the Bulgarian National Astronomical Observatory at Rozhen, observations of 222 double or multiple stars were carried out during three nights in 2011. This is the sixth series of measurements of CCD frames of double and multiple stars obtained at Rozhen. Also in 2011, using the 0.6m telescope of the Serbian Astronomical Station on the mountain of Vidojevica, observations of 208 double or multiple stars were carried out during six nights. This is the first series of measurements of CCD frames of double and multiple stars obtained at this station. In this paper, we present the results for the position angle and angular separation for 337 pairs and residuals for 72 pairs with published orbital elements or linear solutions. These observations have angular separations in the range from 1.37'' to 172.81'', with a median angular separation of 7.66''. We also present the recalculated linear solutions for four pairs and one linear solution that has been calculated for the first time.
- ID:
- ivo://CDS.VizieR/J/AJ/156/199
- Title:
- CCD observations in BVRI bands for TY Pup
- Short Name:
- J/AJ/156/199
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- TY Pup is a well-known bright eclipsing binary with an orbital period of 0.8192 days. New light curves in B, V, (RI)_C_ bands were obtained with the 0.61 m reflector robotic telescope (PROMPT-8) at CTIO in Chile during 2015 and 2017. By analyzing those photometric data with the W-D method, it is found that TY Pup is a low-mass-ratio (q~0.184) and deep-contact binary with a high fill-out factor (84.3%). An investigation of all available times of minimum light including three new ones obtained with the 60 cm and the 1.0 m telescopes at Yunnan Observatories in China indicates that the period change of TY Pup is complex. An upward parabolic variation in the O-C diagram is detected to be superimposed on a cyclic oscillation. The upward parabolic change reveals a long-term continuous increase in the orbital period at a rate of dP/dt=5.57(+/-0.08)x10^-8^ days/yr. The period increase can be explained by mass transfer from the less massive component (M_2_~0.3 M_{sun}_) to the more massive one (M_1_~1.65 M_{sun}_). The binary will be merging when it meets the criterion that the orbital angular momentum is less than three times the total spin angular momentum, i.e., J_orb_<3J_rot_. This suggests that the system will finally merge into a rapid-rotating single star and may produce a luminous red nova. The cyclic oscillation in the O-C diagram can be interpreted by the light-travel time effect via the presence of a third body.
- ID:
- ivo://CDS.VizieR/J/A+AS/100/517
- Title:
- CCD Observations of wide visual double stars
- Short Name:
- J/A+AS/100/517
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/A+AS/139/425
- Title:
- CCD photometry and astrometry of double stars
- Short Name:
- J/A+AS/139/425
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photometric and astrometric data of about 280 visual double stars of the "intermediate" class, i.e. with angular separations mainly in the range 2"<{rho}<12". The observations have been obtained in 1991-92 with a CCD camera attached to the 91cm Dutch telescope at ESO La Silla, Chile. Differential magnitudes of the double star components as well as magnitudes and colour indices of the individual components have been determined in the Cousins V and I passbands with an internal error of about 0.005mag and an external accuracy of less than 0.03mag. In addition, angular separations have been secured to an internal accuracy of 0.004" and position angles to about 0.05{deg}.
- ID:
- ivo://CDS.VizieR/J/A+A/374/132
- Title:
- CCD photometry and astrometry of double stars
- Short Name:
- J/A+A/374/132
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new astrometric and photometric data for 253 visual double stars of the "intermediate" class, i.e. with angular separations in the range 1 to 15 arcsec. The multi-colour observations were obtained in 1992-94 as part of the ESO Key Programme "Visual Double Stars" performed at La Silla Observatory (Chile). Differential magnitudes and colours have been secured in a systematic way while component magnitudes and colour indices have been determined in the V and I passbands of the Cousins standard system in good photometric conditions only. Internal and mean external errors are respectively smaller than 0.01mag and a few hundred of a magnitude (0.02 to 0.03mag). Relative positions are obtained as a by-product with internal errors of the order of 0.006arcsec in angular separation and 0.08{deg} in position angle. Final accuracies are thoroughly discussed: we illustrate the overall excellent quality of the data and estimate the quality degradation for angular separations barely larger than the width of the seeing disk.
- ID:
- ivo://CDS.VizieR/J/MNRAS/246/433
- Title:
- CCD photometry & APM parameters for galaxies
- Short Name:
- J/MNRAS/246/433
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The sequences for UKS fields 152 246 and 249 appear to be discrepant with the plate matching in the APM survey, and so may not be completely reliable.
