- ID:
- ivo://CDS.VizieR/J/A+A/559/A70
- Title:
- Blue wing of the 2p-1s He_2_ line
- Short Name:
- J/A+A/559/A70
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The shape and broadening of He lines affects radiative transport in dense, He-rich, stellar atmospheres. At wavelengths inaccessible for direct observation, we rely on theoretical calculations of self-broadening to support stellar structure and spectral modeling. In this work, we examine lines of He due to 1s-2p and 2p-3s transitions. The line profiles are analyzed in terms of a unified theory of spectral line broadening using ab initio potential energies that have been recently determined. For temperatures up to 20000K, the linear dependence of width and shift on gas density and the non-linear dependence on temperature of the Lorentzian core of the resonance line are described. Beyond the conventional symmetrical Lorentzian core, we show that they are asymmetrical and have significant additional contributions on the short wavelength side. This blue asymmetry is a consequence of maxima in the corresponding He2 potential energy difference curves at short and intermediate internuclear distance. Over a limited range of density and temperature, laboratory measurements in the visible and near infrared can be used to validate the potentials that underlie the spectral line profile theory, which is useful for modeling spectra over the extreme ranges of temperature and density encountered in stellar and planetary atmospheres.
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- ID:
- ivo://CDS.VizieR/J/AN/338/453
- Title:
- BM CVn V-band differential light curve
- Short Name:
- J/AN/338/453
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We perform detailed time series analysis for V-band photometry of BM CVn to investigate the characteristics of its magnetic activity in both long and short time scale and also to estimate its differential rotation.
- ID:
- ivo://CDS.VizieR/J/A+A/488/1221
- Title:
- BMW-Chandra source catalog
- Short Name:
- J/A+A/488/1221
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the BMW-Chandra source catalogue drawn from essentially all Chandra ACIS-I pointed observations with an exposure time in excess of 10ks public as of March 2003 (136 observations). Using the wavelet detection algorithm developed by Lazzati et al. (1999ApJ...524..414) and Campana et al. (1999ApJ...524..423C), which can characterise both point-like and extended sources, we identified 21325 sources. Among them, 16758 are serendipitous, i.e. not associated with the targets of the pointings, and do not require a non-automated analysis. This makes our catalogue the largest compilation of Chandra sources to date. The 0.5-10keV absorption corrected fluxes of these sources range from ~3x10^-16^ to 9x10^-12^erg/cm^2^/s with a median of 7x10^-15^erg/cm^2^/s.
- ID:
- ivo://org.gavo.dc/bgds/q/sia
- Title:
- Bochum Galactic Disk Survey (BGDS) images
- Short Name:
- bgds sia
- Date:
- 27 Dec 2024 08:31:07
- Publisher:
- The GAVO DC team
- Description:
- The Bochum Galactic Disk Survey is a project to monitor the stellar content of the Galactic disk in a 6 degree wide stripe centered on the Galactic plane. The data has been recorded from September 2010 to September 2019 with the RoBoTT Telecsope at the Universitaetssternwarte Bochum near Cerro Armazones in the Chilean Atacama desert. It contains measurements of more than 2x10^7 stars. The second and final data release contains follow-up observations from January 2017 to September 2019 in Sloan r and i and intermittent measurements in Johnson UVB, Sloan z and the narrowbands OIII, NB, Halpha and SII.
- ID:
- ivo://org.gavo.dc/bgds/l/ssa
- Title:
- Bochum Galactic Disk Survey (BGDS) light curves
- Short Name:
- BGDS TS SSAP
- Date:
- 27 Dec 2024 08:31:01
- Publisher:
- The GAVO DC team
- Description:
- This service exposes the light curves of stars produced by the Bochum Galactic Disk Survey; several million light curves are provided in the SDSS i and r bands. The lightcurves are published per-band and are also available through obscore.
- ID:
- ivo://CDS.VizieR/J/AN/336/590
- Title:
- Bochum Galactic Disk Survey: II
- Short Name:
- J/AN/336/590
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is the second in a series describing the southern Galactic Disk Survey (GDS) performed at the Universitatssternwarte Bochum near Cerro Armazones in Chile. Haas et al. (2012, Cat. J/AN/333/706, Paper I) presented the survey design and the characteristics of the observations and data. They identified ~2200 variable stars in an area of 50 square degrees with more than 50 observations in 2011. Here we present the first complete version of the GDS covering all 268 fields with 1323 square degrees along the Galactic disk including revised data from Paper I. The individual fields were observed up to 272 times and comprise a maximum time span between September 2010 and May 2015. We detect a total of 64151 variable sources, which are presented in a catalog including some of their properties and their light curves. A comparison with the International Variable Star Index (VSX) and All Sky Automated Survey (ASAS) indicates that 56794 of these sources are previously unknown variables. Furthermore, we present U, B, V, r', i', z' photometry for all sources within the GDS, resulting in a new multi-color catalog of nearly 16x10^6^ sources detected in at least one filter. Both the GDS and the near-infrared VISTA Variables in the Via Lactea survey (VVV) complement each other in the overlap area of about 300 square degrees enabling future comparison studies.
- ID:
- ivo://CDS.VizieR/J/AN/333/706
- Title:
- Bochum survey of the southern Galactic disk
- Short Name:
- J/AN/333/706
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We are monitoring a 6{deg} wide stripe along the southern Galactic disk simultaneously in the r and i bands, using a robotic 15-cm twin telescope of the Universitatsternwarte Bochum near Cerro Armazones in Chile. Utilising the telescope's 2.7{deg} field of view, the survey aims at observing a mosaic of 268 fields once per month and to monitor dedicated fields once per night. The survey reaches a sensitivity from 10m down to 18m (AB system), with a completeness limit of r~15.5m and i~14.5m which - due to the instrumental pixel size of 2.4" - refers to stars separated by >3". This brightness range is ideally suited to examine the intermediately bright stellar population supposed to be saturated in deep variability surveys with large telescopes. To connect to deep surveys or to explore faint long term variables, coadded images of several nights reach a depth of ~20m. The astrometric accuracy is better than 1", as determined from the overlap of neighbouring fields. We describe the survey design, the data properties and our procedures to derive the light curves and to extract variable stars. We present a list of ~2200 variable stars identified in 50 square degrees with 50-80 observations between May and October 2011. For bright stars the variability amplitude A reaches down to A~0.05m, while at the faint end variations of A>1m are detected. About 200 stars were known to be variable, and their amplitudes and periods - as far as determinable from our six month monitoring - agree with literature values, demonstrating the performance of the Bochum Galactic Disk Survey.
- ID:
- ivo://CDS.VizieR/J/A+A/597/A118
- Title:
- Bok globule BHR 160 radio lines spectra
- Short Name:
- J/A+A/597/A118
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- BHR160 is a virtually unstudied cometary globule within the Sco OB4 association in Scorpius at a distance of 1600pc. It is part of a system of cometary clouds which face the luminous O star HD155806. BHR160 is special because it has an intense bright rim. We attempt to derive physical parameters for BHR160 and to understand its structure and the origin of its peculiar bright rim. BHR160 was mapped in the ^12^CO, ^13^CO and C^18^O (2-1) and (1-0) and CS (3-2) and (2-1) lines. These data, augmented with stellar photometry derived from the ESO VVV survey, were used to derive the mass and distribution of molecular material in BHR160 and its surroundings. Archival mid-infrared data from the WISE satellite was used to find IR excess stars in the globule and its neighbourhood.
- ID:
- ivo://irsa.ipac/Bolocam_GPS/Catalog/BGPSv1
- Title:
- Bolocam Galactic Plane Survey Catalog v1
- Short Name:
- Bolocam GPS v1
- Date:
- 01 Oct 2018 20:27:21
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- The Version 2 release (hereafter v2) of the BGPS data includes images and a catalog. It is described in Ginsburg et al (2013). The new images have improved fidelity and more uniform noise. The fields include all those in the original v1 release and some new data. There are new fields included in the BGPS v2 release, primarily in the outer galaxy but including some expansions in the inner galaxy. These include M17, IRAS 22172, a significant expansion in l and b around the l=110 region, Mon R2, NGC 2264, parts of the Orion A and B clouds, Sharpless 235, and scattered IRAS+CO selected fields at longitude 119, 123, 126, 129, 154, 169, 181, 182, 195, 201, and 217. IRSA provides a coverage map. There is a new catalog associated with the v2 images. The sources were extracted using Bolocat with parameters set in the same way as for the v1 catalog. There are many sources in v1 that are not in v2 and vice-versa. These discrepancies occur primarily for faint sources with low signal-to-noise. Objects in both catalogs are likely to be real since catalog parameters were selected to minimize false positives. Changing the quality of the images and the structure of the noise highlights some new objects and obscures others. The v2 catalog has about a 75% overlap with the v1 catalog. The differences are explored in more detail in the Ginsburg et al (2013). The flux calibration offset identified in the version 1 data is now understood. The version 2 data are brighter, on average, by approximately a factor 1.5, but the factor varies from source to source. The v2 catalog should be used instead of the v1 catalog. The source of the error was the incorrect application of a flux calibration solution. Contreras et al (2013) noted a 4.7 arcsecond offset between the BGPS v1 catalog and the ATLASGAL catalog. We believe this is caused by an offset of that magnitude (~3-4 arcseconds) in a few fields that have an inordinate number of sources extracted; the pointing accuracy in the vast majority of the BGPS fields, based on a comparison to Herschel Hi-Gal images, is better than 4 arcseconds, but the mean offset is within 2 arcseconds of zero.
- ID:
- ivo://irsa.ipac/Bolocam_GPS/Catalog/BGPSv2.1
- Title:
- Bolocam Galactic Plane Survey Catalog v2.1
- Short Name:
- Bolocam GPS v2.1
- Date:
- 01 Oct 2018 20:27:21
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- The Version 2 release (hereafter v2) of the BGPS data includes images and a catalog. It is described in Ginsburg et al (2013). The new images have improved fidelity and more uniform noise. The fields include all those in the original v1 release and some new data. There are new fields included in the BGPS v2 release, primarily in the outer galaxy but including some expansions in the inner galaxy. These include M17, IRAS 22172, a significant expansion in l and b around the l=110 region, Mon R2, NGC 2264, parts of the Orion A and B clouds, Sharpless 235, and scattered IRAS+CO selected fields at longitude 119, 123, 126, 129, 154, 169, 181, 182, 195, 201, and 217. IRSA provides a coverage map. There is a new catalog associated with the v2 images. The sources were extracted using Bolocat with parameters set in the same way as for the v1 catalog. There are many sources in v1 that are not in v2 and vice-versa. These discrepancies occur primarily for faint sources with low signal-to-noise. Objects in both catalogs are likely to be real since catalog parameters were selected to minimize false positives. Changing the quality of the images and the structure of the noise highlights some new objects and obscures others. The v2 catalog has about a 75% overlap with the v1 catalog. The differences are explored in more detail in the Ginsburg et al (2013). The flux calibration offset identified in the version 1 data is now understood. The version 2 data are brighter, on average, by approximately a factor 1.5, but the factor varies from source to source. The v2 catalog should be used instead of the v1 catalog. The source of the error was the incorrect application of a flux calibration solution. Contreras et al (2013) noted a 4.7 arcsecond offset between the BGPS v1 catalog and the ATLASGAL catalog. We believe this is caused by an offset of that magnitude (~3-4 arcseconds) in a few fields that have an inordinate number of sources extracted; the pointing accuracy in the vast majority of the BGPS fields, based on a comparison to Herschel Hi-Gal images, is better than 4 arcseconds, but the mean offset is within 2 arcseconds of zero.
