- ID:
- ivo://CDS.VizieR/J/AcA/63/429
- Title:
- VI light curves of 10 variables in NGC288
- Short Name:
- J/AcA/63/429
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A search for variable stars in the globular cluster NGC 288 was carried out using a time-series of CCD images in the V and I filters. The photometry of all stellar sources in the field of view of our images, down to V~19mag, was performed using difference image analysis (DIA). For stars of~15mag, measurement accuracies of ~8mmag and ~10mmag were achieved for V and I respectively. Three independent search strategies were applied to the 5525 light curves but no new variables were found above the threshold limits characteristic of our data set. The use of older data from the literature combined with the present data allowed the refinement of the periods of all known variables. Fourier light curve decomposition was performed for the RRab and the RRc stars to obtain an estimate of [Fe/H]_ZW_=-1.62+/-0.02 (statistical) +/-0.14 (systematic). A true distance modulus of 14.768+/-0.003mag (statistical) +/-0.042mag (systematic), or a distance of 8.99+/-0.01kpc (statistical) +/-0.17kpc (systematic) was calculated from the RRab star. The RRc star predicts a discrepant distance about one kiloparsec shorter but it is possibly a Blazhko variable. An independent distance from the P-L relationship for SX Phe stars leads to a distance of 8.9+/-0.3kpc. The SX Phe stars V5 and V9 are found to be double mode pulsators.
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- ID:
- ivo://CDS.VizieR/J/A+A/550/A93
- Title:
- VI light curves of V383 Sco
- Short Name:
- J/A+A/550/A93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The system V383 Sco was discovered to be an eclipsing binary star at the beginning of the twentieth century. This system has one of the longest orbital periods known (13.5yr) and was initially classified as a zeta Aur-type eclipsing variable. It was then forgotten about for decades, with no progress made in understanding it. This study provides a detailed look at the system V383 Sco, using new data obtained before, during and after the last eclipse, which occurred in 2007/8. There was a suspicion that this system could be similar to eclipsing systems with extensive dusty disks like EE Cep and epsilon Aur. This and other, alternative hypotheses are considered here. The All Sky Automated Survey (ASAS-3) V and I light curves have been used to examine apparent magnitude and colour changes. Low- and high- resolution spectra have been obtained and used for spectral classification, to analyse spectral line profiles, as well as to determine the reddening, radial velocities and the distance to the system. The spectral energy distribution (SED) was analysed using all available photometric and spectroscopic data. Using our own original numerical code, we performed a very simplified model of the eclipse, taking into account the pulsations of one of the components. The low-resolution spectrum shows apparent traces of molecular bands, characteristic of an M-type supergiant. The presence of this star in the system is confirmed by the SED, by a strong dependence of the eclipse depth on the photometric bands, and by the nature of pulsational changes. The presence of a very low excitation nebula around the system has been inferred from [OI] 6300{AA} emission in the high-resolution spectrum. Analysis of the radial velocities, reddening, and period-luminosity relation for Mira-type stars imply a distance to the V383 Sco system of 8.4+/-0.6kpc. The distance to the nearby V381 Sco is 6.4+/-0.8kpc. The very different and oppositely directed radial velocities of these two systems (89.8km/s vs -178.8km/s) seem to be in agreement with a bulge/bar kinematic model of the Galactic centre and inconsistent with purely circular motion. Conclusions. We have found strong evidence for the presence of a pulsating M-type supergiant in the V383 Sco system. This supergiant periodically obscures the much more luminous F0 I-type star, causing the deep (possibly total) eclipses which vary in duration and shape.
- ID:
- ivo://CDS.VizieR/J/BaltA/14/1
- Title:
- Vilnius photometry in a Cam area
- Short Name:
- J/BaltA/14/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The paper gives the results of seven-color CCD photometry in the Vilnius system of 1376 stars down to 15.5mag in the area of the Galactic equator (l=146{deg}, b=+2.6{deg}) in Camelopardalis. Photometric spectral and luminosity classes, interstellar extinctions and distances of the stars are determined.
- ID:
- ivo://CDS.VizieR/J/BaltA/12/301
- Title:
- Vilnius photometry in Barnard 1
- Short Name:
- J/BaltA/12/301
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectral and luminosity classes, absolute magnitudes. color excesses, interstellar extinctions and distances are determined for 98 stars down to 13mag in the Barnard 1 dark cloud belonging to the Per OB2 association. The classification of stars is based on their photoelectric photometry in the Vilnius seven-color photometric system. The extinction vs. distance diagram exhibits the presence of two dust layers at 150 and 230pc distances. The distance of the first cloud, which gives an extinction AV of 0.3mag, coincides with the distance of the Taurus dark cloud complex. The second cloud with much larger extinction is about at the same distance as the clouds in the direction of the nearby objects: reflection nebula NGC 1333 and open cluster IC 348.
- ID:
- ivo://CDS.VizieR/J/BaltA/10/349
- Title:
- Vilnius photometry in Cam/Per
- Short Name:
- J/BaltA/10/349
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 157 stars down to 11th mag in a 3{deg}x4{deg} area at l=149{deg}, b=-0.3{deg} have been measured in the Vilnius photometric system. Magnitudes V, color indices, spectral classes, absolute magnitudes, color excesses and distances of the stars are determined. The interstellar extinction in all the area appears at a distance of about 100pc, grows monotonically and at a distance of 500pc it reaches ~2mag in the area of the dark cloud L1391 and 0.7-1.7mag in the remaining area. At larger distances the extinction is affected by a selection effect.
- ID:
- ivo://CDS.VizieR/J/BaltA/11/75
- Title:
- Vilnius photometry in Cam-Per border
- Short Name:
- J/BaltA/11/75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Seven-color photometry in the Vilnius system for 309 stars down to 12.5mag in the area along the galactic equator near the Camelopardalis and Perseus border is presented. Photometric spectral and luminosity classes of the stars are determined.
- ID:
- ivo://CDS.VizieR/J/AJ/161/149
- Title:
- Vilnius photometry in IC 59 and IC 63
- Short Name:
- J/AJ/161/149
- Date:
- 20 Jan 2022
- Publisher:
- CDS
- Description:
- Optical and infrared continuum polarization from the interstellar medium is driven by radiative processes aligning the grains with the magnetic field. While a quantitative, predictive theory of radiative alignment torques (RATs) exists and has been extensively tested, several parameters of the theory remain to be fully constrained. In a recent paper, Medan & Andersson showed that the polarization efficiency (and therefore grain alignment efficiency) at different locations in the wall of the Local Bubble (LB) could be modeled as proportional to the integrated light intensity from the surrounding stars and OB associations. Here we probe that relationship at high radiation field intensities by studying the extinction and polarization in the two reflection nebulae IC59 and IC63 in the Sh2-185 HII region, illuminated by the B0 IV star {gamma}Cassiopeia. We combine archival visual polarimetry with new seven-band photometry in the Vilnius system, to derive the polarization efficiency from the material. We find that the same linear relationship seen in the LB wall also applies to the Sh2-185 region, strengthening the conclusion from the earlier study.
- ID:
- ivo://CDS.VizieR/J/BaltA/15/483
- Title:
- Vilnius photometry in LDN 935
- Short Name:
- J/BaltA/15/483
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Magnitudes and color indices of 439 stars down to V~17.5mag in the eight-color Vilnius + I photometric system were obtained in four areas of diameters 20' within the dark cloud L935 separating the North America and Pelican nebulae. Spectral types, interstellar color excesses, extinctions and distances of stars were determined from the photometric data.
- ID:
- ivo://CDS.VizieR/J/BaltA/11/219
- Title:
- Vilnius photometry in MBM12
- Short Name:
- J/BaltA/11/219
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of photoelectric photometry in the Vilnius seven-color system are given for 152 stars down to 12.2mag in the area of the molecular cloud MBM 12 and the dust clouds L1454 and L1457 in Aries. The results of photometric classification of stars are also given. The investigation of interstellar extinction in the area is described in the next paper, Straizys et al., Cat. <J/BaltA/11/231>.
- ID:
- ivo://CDS.VizieR/J/BaltA/10/319
- Title:
- Vilnius photometry in NGC 1499
- Short Name:
- J/BaltA/10/319
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Vilnius seven-color photometry has been obtained for 238 stars down to 13th mag in the area of the California Nebula in Perseus. For nearly all of the stars photometric spectral classes, luminosity classes, absolute magnitudes, interstellar reddenings, extinctions and distances are determined. The present paper contains the results of photometry and the parameters of the stars.
