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231. BMW-Chandra source catalog
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.
232. Bochum Galactic Disk Survey (BGDS) images
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.
233. Bochum Galactic Disk Survey (BGDS) light curves
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.
234. Bochum Galactic Disk Survey: II
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.
235. Bochum survey of the southern Galactic disk
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.
236. Bonn 1420 MHz Survey
ID:
ivo://nasa.heasarc/skyview/1420mhz
Title:
Bonn 1420 MHz Survey
Short Name:
1420MHz
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This survey was taken with the Bonn Stockert 25m telescope. It was distributed on the NRAO <i>Images from the Radio Sky</i> CD-ROM. This image was delivered as a four map mosaic but was combined into a single map before being included in <i>SkyView</i>. Provenance: Max Planck Institute for Radio Astronomy, generated by P. Reich and W. Reich. This is a service of NASA HEASARC.
237. Bootes field deep LOFAR 150MHz imaging
ID:
ivo://CDS.VizieR/J/A+A/620/A74
Title:
Bootes field deep LOFAR 150MHz imaging
Short Name:
J/A+A/620/A74
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have conducted a deep survey (with a central rms of 55uJy) with the LOw Frequency ARray (LOFAR) at 120-168MHz of the Bootes field, with an angular resolution of 3.98"x6.45", and obtained a sample of 10091 radio sources (5{sigma} limit) over an area of 20deg^2^. The astrometry and flux scale accuracy of our source catalog is investigated. The resolution bias, incompleteness and other systematic effects that could affect our source counts are discussed and accounted for. The derived 150MHz source counts present a flattening below sub-mJy flux densities, that is in agreement with previous results from high- and low- frequency surveys. This flattening has been argued to be due to an increasing contribution of star-forming galaxies and faint active galactic nuclei. Additionally, we use our observations to evaluate the contribution of cosmic variance to the scatter in source counts measurements. The latter is achieved by dividing our Bootes mosaic into 10 non-overlapping circular sectors, each one with an approximate area of 2deg^2^. The counts in each sector are computed in the same way as done for the entire mosaic. By comparing the induced scatter with that of counts obtained from depth observations scaled to 150MHz, we find that the 1{sigma} scatter due to cosmic variance is larger than the Poissonian errors of the source counts, and it may explain the dispersion from previously reported depth source counts at flux densities S<1mJy. This work demonstrates the feasibility of achieving deep radio imaging at low-frequencies with LOFAR.
238. Bootes field LOFAR 150-MHz observations
ID:
ivo://CDS.VizieR/J/MNRAS/460/2385
Title:
Bootes field LOFAR 150-MHz observations
Short Name:
J/MNRAS/460/2385
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first wide area (19 deg^2^), deep (~=120-150 {mu}Jy/beam), high-resolution (5.6x7.4-arcsec) LOFAR High Band Antenna image of the Bootes field made at 130-169MHz. This image is at least an order of magnitude deeper and 3-5 times higher in angular resolution than previously achieved for this field at low frequencies. The observations and data reduction, which includes full direction-dependent calibration, are described here. We present a radio source catalogue containing 6276 sources detected over an area of 19deg^2^, with a peak flux density threshold of 5{sigma}. As the first thorough test of the facet calibration strategy, introduced by van Weeren et al. (2016ApJS..223....2V), we investigate the flux and positional accuracy of the catalogue. We present differential source counts that reach an order of magnitude deeper in flux density than previously achieved at these low frequencies, and show flattening at 150-MHz flux densities below 10 mJy associated with the rise of the low flux density star-forming galaxies and radio-quiet AGN.
239. Bordeaux AC Zone Data Reduced to ACRS
ID:
ivo://CDS.VizieR/I/228
Title:
Bordeaux AC Zone Data Reduced to ACRS
Short Name:
I/228
Date:
21 Oct 2021
Publisher:
CDS
Description:
The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the Bordeaux Zone, whose plates are centered between declinations +11 and +17 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of over 223,000 stars on eq. J2000.0, epoch of observation. Additionally, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added for additional identification purposes.
240. BOSS narrow CIV absorption lines. III.
ID:
ivo://CDS.VizieR/J/MNRAS/462/2980
Title:
BOSS narrow CIV absorption lines. III.
Short Name:
J/MNRAS/462/2980
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper, we extend our work of IV {lambda}{lambda}1548,1551 narrow absorption lines (NALs) with z_abs_<<z_em_ on quasar spectra of the Baryon Oscillation Spectroscopic Survey (BOSS) to collect CIV NALs with z_abs_<=z_em_ from blue to red wings of CIV {lambda}1549 emission lines. Together with IV NALs with 1.4544<=z_abs_<=4.9224 in surveyed spectral region redward of Ly{alpha} until red wing of CIV {lambda}1549 emission line. We find that the stronger CIV NALs tend to be the more saturated absorptions, and associated systems (z_abs_~=z_em_) seem to have larger absorption strengths when compared to intervening ones (z_abs_<<z_em_). The redshift density evolution behaviour of absorbers (the number of absorbers per redshift path) is similar to the history of the cosmic star formation. When compared to the quasar-frame velocity ({beta}) distribution of MgII absorbers, the {beta} distribution of CIV absorbers is broader at {beta}~=0, shows longer extended tail, and exhibits a larger dispersion for environmental absorptions. In addition, for associated CIV absorbers, we find that low-luminosity quasars seem to exhibit smaller {beta} and stronger absorptions when compared to high-luminosity quasars.

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