- ID:
- ivo://CDS.VizieR/J/MNRAS/474/5287
- Title:
- BeSOS Be stars stellar parameters
- Short Name:
- J/MNRAS/474/5287
- Date:
- 07 Dec 2021 13:16:10
- Publisher:
- CDS
- Description:
- The Be phenomenon is present in about 20 per cent of B-type stars. Be stars show variability on a broad range of time-scales, which in most cases is related to the presence of a circumstellar disc of variable size and structure. For this reason, a time-resolved survey is highly desirable in order to understand the mechanisms of disc formation, which are still poorly understood. In addition, a complete observational sample would improve the statistical significance of the study of stellar and disc parameters. The 'Be Stars Observation Survey' (BeSOS) is a survey containing reduced spectra obtained using the Pontifica Universidad Catolica High Echelle Resolution Optical Spectrograph (PUCHEROS) with a spectral resolution of 17000 in the range 4260-7300{AA}. BeSOS's main objective is to offer consistent spectroscopic and time-resolved data obtained with one instrument. The user can download or plot the data and obtain stellar parameters directly from the website. We also provide a star-by-star analysis based on photometric, spectroscopic and interferometric data, as well as general information about the whole BeSOS sample. Recently, BeSOS led to the discovery of a new Be star HD 42167 and facilitated study of the V/R variation of HD 35165 and HD 120324, the steady disc of HD 110335 and the Be shell status of HD 127972. Optical spectra used in this work, as well as the stellar parameters derived, are available online at http://besos.ifa.uv.cl.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/other/RAA/15.1325
- Title:
- Be stars in LAMOST DR1
- Short Name:
- J/other/RAA/15.1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on searching for Classical B-type emission-line (CBe) stars in the first data release of the Large Sky Area Multi-Object fiber Spectroscopic Telescope (LAMOST; also called the Guo Shou Jing Telescope). A total of 192 objects (including 12 previously known CBes) were identified as CBe candidates with prominent HeI {lambda}4387, HeI {lambda}4471 and MgII {lambda}4481 absorption lines, as well as H{beta} {lambda}4861 and H{alpha} {lambda}6563 emission lines. These candidates significantly increase the currently known sample of CBes by about 8%. Most of the CBe candidates are distributed near the Galactic Anti-Center due to the observing strategy used for LAMOST. Only two CBes are in star clusters. These two CBes have ages of 15.8 and 398Myr, respectively.
- ID:
- ivo://CDS.VizieR/J/AJ/134/1560
- Title:
- BEST periodic variable stars in IR01 field
- Short Name:
- J/AJ/134/1560
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on observations of the COROT IR01 field with the Berlin Exoplanet Search Telescope (BEST). BEST is a small-aperture telescope with a wide field of view (FOV). It is dedicated to searching for variable stars within the target fields of the COROT space mission to aid in minimizing false-alarm rates, and identifying potential targets for additional science. COROT's observational program started in 2007 February, with the "initial run" field (IR01) observed for about 2 months. BEST observed this field for 12 nights spread over 3 months in winter 2006. From the total of 30,426 stars observed in the IR01 field, 3769 were marked as suspected variable stars, and 54 of these showed clear periodicity. From these, 19 periodic stars are within the part of the COROT FOV covered in our data set.
- ID:
- ivo://CDS.VizieR/J/AJ/136/654
- Title:
- BEST periodic variable stars in LRa1 field
- Short Name:
- J/AJ/136/654
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we report on observations of the CoRoT LRa1 field with the Berlin Exoplanet Search Telescope (BEST). The current paper is part of a series of papers describing the results of our stellar variability survey. The BEST is a small aperture telescope with a wide field of view (FOV). It is dedicated to searching for stellar variability within the target fields of the CoRoT space mission to aid in minimizing false-alarm rates and identify potential targets for additional science. The LRa1 field is CoRoT's second long run field located in the galactic anticenter direction. We observed the LRa1 stellar field on 23 nights between November and March 2005/2006. From 6099 stars marked as variable, 39 were classified as periodic variable stars and 27 of them are within the CoRoT FOV. We also confirmed the variability for four stars listed in the General Catalogue of Variable Stars (GCVS).
- ID:
- ivo://CDS.VizieR/J/AJ/137/3911
- Title:
- BEST periodic variable stars in LRc2 field
- Short Name:
- J/AJ/137/3911
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on photometric observations of the CoRoT LRc2 field with the new robotic Berlin Exoplanet Search Telescope II (BEST II). The telescope system was installed and commissioned at the Observatorio Cerro Armazones, Chile, in 2007. BEST II is a small aperture telescope with a wide field of view dedicated to the characterization of the stellar variability primarily in CoRoT target fields with high stellar densities. The CoRoT stellar field LRc2 was observed with BEST II up to 20 nights in 2007 July and August. From the acquired data containing about 100,000 stars, 426 new periodic variable stars were identified and 90% of them are located within the CoRoT exoplanetary CCD segments and may be of further interest for CoRoT additional science programs.
- ID:
- ivo://CDS.VizieR/J/AJ/134/766
- Title:
- BEST variable stars in LRc1 field
- Short Name:
- J/AJ/134/766
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The COROT space mission will monitor several target fields for up to 150 days to perform asteroseismology and to search for extrasolar planets by photometric transits. Variable stars in the target fields are important objects for additional scientific studies but can also disturb the search for planetary transits. A variability characterization of the target fields prior to COROT observations is therefore important for two reasons: to find interesting variable stars to monitor further and to make an analysis of the impact of the variable stars on detecting extrasolar planet transits with COROT. The Berlin Exoplanet Search Telescope (BEST) is a small wide-angle telescope dedicated to high-precision photometry. It has observed a 9deg^2^ field of view centered at (RA,DE)=(19:00:00.0+00:01:55.2) (J2000.0) over 98 nights to search for variable stars in the surroundings of the first long-run target field (LRc1) of the COROT space mission. In this data set we identified 92 periodic variable stars, 86 of which are new discoveries and 6 of which are known from the General Catalogue of Variable Stars (GCVS). For five of the GCVS stars, variability could not be confirmed. Forty-three of the 92 detected periodic variable stars are identified as eclipsing binaries. We have evaluated the completeness of our survey for eclipsing binaries by comparing it to the expected fraction of eclipsing binaries based on Hipparcos observations. From this evaluation we show that the BEST data set presented here has a completeness of 20%-30% for periods longer than 1 day and is complete relative to Hipparcos for short-period binaries.
- ID:
- ivo://CDS.VizieR/J/AJ/160/32
- Title:
- beta Cephei light curves from KELT project
- Short Name:
- J/AJ/160/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a search for Galactic {beta} Cephei stars, which are massive pulsating stars with both pressure modes and mixed modes. Thus, these stars can serve as benchmarks for seismological studies of the interiors of massive stars. We conducted the search by performing a frequency analysis on the optical light curves of known O- and B-type stars with data from the Kilodegree Extremely Little Telescope exoplanet survey. We identify 113 {beta} Cephei stars, of which 86 are new discoveries, which altogether represent a 70% increase in the number currently known. An additional 97 candidates are identified. Among our targets, we find five new eclipsing binaries and 22 stars with equal frequency spacings suggestive of rotational splitting of nonradial pulsation modes. Candidates for runaway stars among our targets and a number of interesting individual objects are discussed. Most of the known and newly discovered {beta} Cephei stars will be observed by the Transiting Exoplanet Survey Satellite mission, providing by far the most comprehensive observational data set of massive main-sequence pulsating stars of sufficient quality for detailed asteroseismic studies. Future analysis of these light curves has the potential to dramatically increase our understanding of the structure of stellar interiors and the physical processes taking place therein.
- ID:
- ivo://CDS.VizieR/J/A+A/477/907
- Title:
- Beta Cephei stars in the ASAS-3 data. I.
- Short Name:
- J/A+A/477/907
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyse V-filter photometry of 41 known Beta Cephei-type stars. The ASAS-3 photometry is combined with the archival data, if available, to determine long-term stability of periods and amplitudes of excited modes. We detected amplitude changes in three Beta Cephei stars, BW Cru, V836 Cen, and V348 Nor. Period changes were found in KK Vel and V836 Cen. Our analysis shows that intrinsic period changes are more common among multiperiodic stars, apparently because they are caused by some kind of mode interaction. In addition, we found new modes for seven stars, and for ten others we provide new solutions or remove ambiguities in the detected frequencies. One candidate hybrid Beta Cephei/SPB star, HD 133823, is discovered.
- ID:
- ivo://CDS.VizieR/J/A+A/477/917
- Title:
- Beta Cephei stars in the ASAS-3 data. II.
- Short Name:
- J/A+A/477/917
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analysed ASAS-3 photometry of bright early-type stars with the goal of finding new Beta Cephei stars. We were particularly interested in Beta Cephei stars that would be good for seismic analysis, i.e., stars that (i) have a large number of excited modes, (ii) show rotationally split modes, (iii) are components of eclipsing binary systems, (iv) have low-frequency modes, that is, are hybrid Beta Cephei/SPB stars. Our study was made with a homogeneous sample of over 4100 stars having MK spectral type B5 or earlier. For these stars, the ASAS-3 photometry was analysed by means of a Fourier periodogram. We have discovered 103 Beta Cephei stars, nearly doubling the number of previously known stars of this type. Among these stars, four are components of eclipsing binaries, seven have modes equidistant or nearly equidistant in frequency. In addition, we found five Beta Cephei stars that show low-frequency periodic variations, very likely due to pulsations. We therefore regard them as candidate hybrid Beta Cephei/SPB pulsators. All these stars are potentially very useful for seismic modeling. Moreover, we found Beta Cephei-type pulsations in three late O-type stars and fast period changes in one, HD 168050.
- ID:
- ivo://CDS.VizieR/J/ApJS/208/14
- Title:
- BGPS. IX. Data release 2.
- Short Name:
- J/ApJS/208/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a re-reduction and expansion of the Bolocam Galactic Plane Survey (BGPS), first presented by Aguirre+ (2011ApJS..192....4A) and Rosolowsky+ (2011, J/ApJS/188/123). The BGPS is a 1.1mm survey of dust emission in the Northern galactic plane, covering longitudes -10{deg}<{ell}<90{deg} and latitudes |b|<0.5{deg} with a typical 1{sigma} rms sensitivity of 30-100mJy in a ~33" beam. Version 2 of the survey includes an additional ~20deg^2^ of coverage in the third and fourth quadrants and ~2deg^2^ in the first quadrant. The new data release has improved angular recovery, with complete recovery out to ~80" and partial recovery to ~300", and reduced negative bowls around bright sources resulting from the atmospheric subtraction process. We resolve the factor of 1.5 flux calibration offset between the v1.0 data release and other data sets and determine that there is no offset between v2.0 and other data sets. The v2.0 pointing accuracy is tested against other surveys and is demonstrated to be accurate and an improvement over v1.0. We present simulations and tests of the pipeline and its properties, including measurements of the pipeline's angular transfer function. The Bolocat cataloging tool was used to extract a new catalog, which includes 8594 sources, with 591 in the expanded regions. We have demonstrated that the Bolocat 40" and 80" apertures are accurate even in the presence of strong extended background emission. The number of sources is lower than in v1.0, but the amount of flux and area included in identified sources is larger.
