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BMWHRICAT - Brera Multi-scale Wavelet (BMW) ROSAT HRI Source Catalog

HEASARC
Archive

Overview

The Brera Multi-scale Wavelet ROSAT High Resolution Imager Source Catalog (BMW-HRI) is derived from all ROSAT HRI pointed observations with exposure time longer than 100 seconds available in the ROSAT public archives. The data were analyzed automatically using a wavelet detection algorithm suited to the detection and characterization of both point-like and extended sources. This algorithm is able to detect and disentangle sources in very crowded fields and/or in presence of extended or bright sources. Images have been also visually inspected after the analysis to ensure verification. The final catalog, derived from 4,303 observations, consists of 29,089 sources detected with a detection probability of greater or equal 4.2 sigma. For each source, the primary catalog entries provide name, position, count rate, flux and extension along with the relative errors. In addition, results of cross-correlations with existing catalogs at different wavelengths (FIRST, IRAS, 2MASS and GSC2) are also reported. All these information are available on the web via the DIANA Interface at http://www.asdc.asi.it/diana/. As an external check, the authors compared their catalog with the previously available ROSHRICAT catalog (both in its short and long versions) and were able to recover, for the short version, ~90% of the entries. The sky coverage of the entire HRI data set was computed by means of simulations. The complete BMW-HRI catalog provides a sky coverage of 732 square degrees down to a limiting flux of ~1x10-12 erg/s/cm2 and of 10 square degrees down to ~1x10-14 erg/s/cm2. The authors were able to compute the cosmological log(N)-log(S) distribution down to a flux of about 1.2x10-14 erg/s/cm2.

Catalog Bibcode

2003A&A...399..351P

References

The Brera Multi-scale Wavelet ROSAT HRI source catalogue (BMW-HRI).
    Panzera M.R., Campana S., Covino S., Lazzati D., Mignani R.P.,
    Moretti A., Tagliaferri G.
   <Astron. Astrophys. 399, 351 (2003)>
   =2003A&A...399..351P

Provenance

This online catalog was created by the HEASARC in March 2003 based on an original table obtained from the CDS (ftp://cdsarc.u-strasbg.fr/pub/cats/IX/34/catalog.dat.gz) and its associated ReadMe file.

Description

The BMW-HRI catalog was generated from US and German ROSAT HRI observations for which data have been released to the US ROSAT archive at GSFC and to the German ROSAT archive at MPE up to December 2001. A total number of 4,303 observations with exposure times longer than 100 s were analyzed automatically using a wavelet detection algorithm. The catalog consists of 29,089 sources (detection probability greater or equal 4.2 sigma). For each source name, position, count rate, flux and extension along with the relative errors are given. The catalog also reports results of cross-correlations with existing catalogs at different wavelengths (FIRST, GSC2, 2MASS, and IRAS).

HEASARC Implementation

The original table contained a number of version parameters that appear to have the same value for every entry, and thus the HEASARC has not retained these in its version, but lists their values here:
Parameter             Value

Catalog Version      BMW_2.0
BMW-FIRST Version    BMWFIRST_1.0
BMW-GSC2 Version     BMWGSC2_1.0 or 1 BMWGSC2_1
BMW-2MASS Version    BMW2MASS_1.0
BMW-IRAS Version     BMWIRAS_1.0
BMW CC Version       BMW_X_1.0

Parameters

Name
The BMWHRI Catalog designation of the X-ray source following the IAU naming convention with the prefix 1BMW.

RA
The Right Ascension of the X-ray source in the selected equinox. In the original table this was given in J2000 equatorial coordinates to a precision of 0.01 seconds of time.

Dec
The Declination of the X-ray source in the selected equinox. In the original table this was given in J2000 equatorial coordinates to a precision of 0.1 arcseconds.

LII
The Galactic Longitude of the X-ray source.

BII
The Galactic Latitude of the X-ray source.

RA_Error
The error in Right Ascension of the position of the X-ray source, in arcseconds.

Dec_Error
The error in Declination of the position of the X-ray source, in arcseconds.

Error_Radius
The total positional error of the X-ray source, in arcseconds.

Rebin_Factor
For each HRI event file, the catalog authors extracted and separately analysed 4 concentric images at increasing rebinning factors of 1, 3, 6, and 10, corresponding to pixel sizes of 0.5, 1.5, 3 and 5 arcsec, respectively, in order to follow the instrumental PSF and to avoid the analysis of unnecessarily large images. This parameter represents the rebin factore at which the source was found.

X_Pixel
The X-ray source X coordinate, in pixels.

Y_Pixel
The X-ray Source Y coordinate, in pixels.

Off_Axis
The X-ray source angular offset from the nominal pointing direction or target position, in arcminutes.

Field_Name
The field name, i.e., the name of the nominal target of the observation.

RA_Target
The Right Ascension (in J2000 equatorial coordinates) of the nominal target of the observation.

Dec_Target
The Declination (in J2000 equatorial coordinates) of the nominal target of the observation.

ROR
The Rosat Observation Request (ROR) number of the observation, e.g., 200005.

Sequence_ID
The full observation sequence identifier, e.g., rh200005a00.

Time
The date and time of the start of the observation.

End_Time
The date and time of the end of the observation.

Nominal_Exposure
The nominal exposure time of the HRI observation, in seconds.

Exposure
The exposure time of the HRI observation as calculated from the exposure map,in seconds

Num_Src_Rebin_1
The number of X-ray sources detected with a rebin factor of 1 (pixel size of 0.5 arcseconds).

Num_Src_Rebin_3
The number of X-ray sources detected with a rebin factor of 3 (pixel size of 1.5 arcseconds).

Num_Src_Rebin_6
The number of X-ray sources detected with a rebin factor of 6 (pixel size of 3 arcseconds).

Num_Src_Rebin_10
The number of X-ray sources detected with a rebin factor of 10 (pixel size of 5 arcseconds).

SNR
The Signal-to-Noise Ratio (SNR) of the detected X-ray source.

Wavelet_SNR
The Signal-to-Noise Ratio (SNR) in wavelet space.

Wavelet_Prob
The wavelet probability in gaussian sigmas of the signal being spurious, given the signal to noise in wavelet space and the mean number of counts per pixel. The detection algorithm and its application are fully described in papers by Lazzati et al., 1999ApJ...524..414L and Campana et al., 1999ApJ...524..423C.

Count_Rate
The estimated net count rate of the X-ray source, in counts/second.

Count_Rate_Fit_Err
The error in the count rate derived from the fit procedure, Err1, in counts/second.

Count_Rate_Stat_Err
The statistical error in the count rate, Err2, in counts/second.

Count_Rate_Error
The error in the X-ray source count rate calculated from the maximum of the fit error and the statistical error, i.e, max(Err1,Err2).

Total_Counts
The total counts detected for the X-ray source, i.e., the product of the count rate and the exposure.

Vignet
The vignetting correction.

PSF_Correction
The Point Spread Function (PSF) correction.

Src_Count_Rate
The source count rate obtained from the counting procedure, in counts/second.

Src_Count_Rate_Error
The error in the source count rate from the counting procedure, in counts/second.

Bckgrd_Count_Rate
The estimated background count rate, in counts/second.

Num_Near_Sources
The number of other X-ray sources within 2 sigma of the X-ray source.

NH
The weighted average interstellar hydrogen column density, n_H, in H atoms/cm2 (104 atoms/m2).

Cf_Low
The count rate to flux conversion factor as determined assuming as a reference a Crab-like X-ray spectrum (power law with photon index 2.0), and a very low interstellar column density n_H of 5x1019 /cm2, in units of erg/cm2/count (mJ/m2/count).

Flux_Low
The HRI X-ray flux, as calculated using the conversion factor CF_Low, in erg/cm2/s (mW/m2).

Cf_Full
The count rate to flux conversion factor as determined assuming as a reference a Crab-like X-ray spectrum (power law with photon index 2.0), and the full Galactic interstellar column density n_H, in units of erg/cm2/count (mJ/m2/count).

Flux_Full
The HRI X-ray flux, as calculated using the conversion factor CF_Full, in erg/cm2/s (mW/m2).

Source_Extent
The sigma of the source extent as derived from the fit procedure, in arcseconds.

Source_Extent_Error
The error in the source extent sigma, in arcseconds.

Sigma_Flag
A Y/N flag parameter indicating whether or not the source extent sigma was fixed.

Extent_Flag
A parameter Indicating if the source is either "Point" or "Extended". To assess the source extension criterion, the catalog authors considered the distribution of the source extent as a function of the source off-axis angle (the off_axis parameter). Firstly, they derived the mean value of the source extent (that is the HRI PSF), then they determined the 3 sigma dispersion about the mean. The mean value plus the 3 sigma dispersion provides the threshold for a source possibly being extended. They conservatively classified a source as extended if the source extent error bar was "more than twice from the threshold". For extended sources, the extent_significance parameter reports the number of sigma from the threshold.

Extent_Significance
The significance of the source being extended, i.e., the number of sigma from the threshold for a source possibly being extended.

Chi_Squared
The Chi Squared statistic from the fit procedure.

SASS_Version
The version of the ROSAT SASS processing system that was used to process the HRI field in which the X-ray source was found.

First_Name
The cross-correlated FIRST (CDS Catalog <VIII/59>) source name. A full description of all FIRST parameters can be found at the Web URL http://sundog.stsci.edu/first/catalogs/readme_01oct15.html. As the number of FIRST sources that cross-correlate with each BMW-HRI sources can be, in several cases, more than one, the catalog authors decided to adopt the minimum distance approach. In this way, all the FIRST parameters are for the nearest FIRST source to the X-ray source position.

First_RA
The Right Ascension (J2000) of the cross-correlated FIRST source, in degrees.

First_Dec
The Declination (J2000) of the cross-correlated FIRST source, in degrees.

First_Sidelobe_Flag
This parameter is a warning flag indicating that the FIRST source may be a sidelobe of a nearby bright source.

First_Peak_Flux
The FIRST source peak flux density, in milliJanskies (mJy).

First_Int_Flux
The FIRST source integrated flux density, in milliJanskies (mJy).

First_RMS
The local rms noise estimate at the FIRST source position, in milliJanskies (mJy).

First_Maj_Axis
The FWHM of the major axis of the FIRST source, found using an elliptical Gaussian model, after deconvolution, in arcseconds. Noise can cause the fitted values of the major and minor axes (before deconvolution) to be smaller than the beam size. The corresponding deconvolved size values are given as zero in those cases.

First_Min_Axis
The FWHM of the minor axis of the FIRST source, found using an elliptical Gaussian model, after deconvolution, in arcseconds. Noise can cause the fitted values of the major and minor axes (before deconvolution) to be smaller than the beam size. The corresponding deconvolved size values are given as zero in those cases.

First_PA
The position angle of the FIRST source, found using an elliptical Gaussian model, after deconvolution, in degrees.

First_Meas_Maj_Axis
The measured FWHM of the major axis of the FIRST source, i.e., before deconvolution, in arcseconds.

First_Meas_Min_Axis
The measured FWHM of the minor axis of the FIRST source, i.e., before deconvolution, in arcseconds.

First_Meas_PA
The measured position angle of the FIRST source, i.e., before deconvolution, in degrees.

First_BMW_Offset
The angular distance between the FIRST source and the BMW-HRI X-ray source position, in arcseconds.

First_Num_Ctrprt
The number of FIRST cross-correlated objects associated with the BMW-HRI X-ray source.

GSC2_Name
The cross-correlated Guide Star Catalog II (GSC-2, CDS Catalog <I/271>) source name. A full description of GSC-2 can be found at the URL: http://gsss.stsci.edu/Catalogs/GSC/GSC2/gsc2.htm. As the number of GSC-2 sources that cross-correlate with each BMW-HRI source can be, in several cases, more than one, the catalog authors decided to adopt the minimum distance approach. In this approach, all the GSC-2 parameters refer to the source nearest to the position of the BMW-HRI X-ray source.

GSC2_RA
The Right Ascension (J2000) of the cross-correlated GSC-2 source, in degrees.

GSC2_Dec
The Declination (J2000) of the cross-correlated GSC-2 source, in degrees.

GSC2_RA_Error
The error in the Right Ascension of the cross-correlated GSC-2 source, in arcseconds.

GSC2_Dec_Error
The error in the Declination of the cross-correlated GSC-2 source, in arcseconds.

GSC2_Epoch
The epoch of observation of the GSC-2 source, in years.

GSC2_PM_RA
The proper motion in the Right Ascension direction of the cross-correlated GSC-2 source, in mas/yr.

GSC2_PM_Dec
Th proper motion in the Declination direction of the cross-correlated GSC-2 source, in mas/yr.

GSC2_PM_RA_Error
The error in the proper motion in the Right Ascension direction of the cross-correlated GSC-2 source, in mas/yr.

GSC2_PM_Dec_Error
The error in the proper motion in the Declination direction of the cross-correlated GSC-2 source, in mas/yr.

GSC2_Fmag
The F Magnitude of the cross-correlated GSC-2 source.

GSC2_Fmag_Error
The error in the F Magnitude of the cross-correlated GSC-2 source.

GSC2_Jmag
The J Magnitude of the cross-correlated GSC-2 source.

GSC2_Jmag_Error
The error in the J Magnitude of the cross-correlated GSC-2 source.

GSC2_Vmag
The V Magnitude of the cross-correlated GSC-2 source.

GSC2_Vmag_Error
The error in the V Magnitude of the cross-correlated GSC-2 source.

GSC2_Nmag
The N Magnitude of the cross-correlated GSC-2 source.

GSC2_Nmag_Error
The error in the N Magnitude of the cross-correlated GSC-2 source.

GSC2_Maj_Axis
The semi-major axis of the cross-correlated GSC-2 source, in arcseconds.

GSC2_Eccentricity
The eccentricity of the cross-correlated GSC-2 source.

GSC2_PA
The position angle of the cross-correlated GSC-2 source, in degrees.

GSC2_Class_Code
The GSC-2 Catalog class code of the cross-correlated GSC-2 source using the following scheme:

             0: star
             1: galaxy
             2: blend
             3: non-star
             4: unclassified
             5: defect
  

GSC2_BMW_Offset
The angular distance between the GSC-2 source and the BMW-HRI X-ray source position, in arcseconds.

GSC2_Num_Ctrprt
The number of GSC-2 cross-correlated objects associated with the BMW-HRI X-ray source.

TMASS_RA
The Right Ascension (J2000) of the cross-correlated Two Micron All Sky Survey (2MASS) source, in degrees. A full description of the 2MASS project can be found at the Web URL: http://pegasus.phast.umass.edu/. As the number of 2MASS sources that cross-correlate with each BMW-HRI X-ray source can be, in several cases, more than one, the catalog authors decided to adopt the minimum distance approach. In this approach, all the 2MASS parameters refer to the 2MASS source nearest to the position of the BMW-HRI X-ray source.

TMASS_Dec
The Declination (J2000) of the cross-correlated 2MASS source, in degrees. A full description of the 2MASS project can be found at the Web URL: http://pegasus.phast.umass.edu/. As the number of 2MASS sources that cross-correlate with each BMW-HRI X-ray source can be, in several cases, more than one, the catalog authors decided to adopt the minimum distance approach. In this approach, all the 2MASS parameters refer to the 2MASS source nearest to the position of the BMW-HRI X-ray source.

TMASS_Jmag
The J magnitude of the cross-correlated 2MASS source.

TMASS_Jmag_Error
The error in the J magnitude of the cross-correlated 2MASS source.

TMASS_Hmag
The H magnitude of the cross-correlated 2MASS source.

TMASS_Hmag_Error
The error in the H magnitude of the cross-correlated 2MASS source.

TMASS_Kmag
The K magnitude of the cross-correlated 2MASS source.

TMASS_Kmag_Error
The error in the K magnitude of the cross-correlated 2MASS source.

TMASS_BMW_Offset
The angular distance between the 2MASS source and the BMW-HRI X-ray source position, in arcseconds.

TMASS_Num_Ctrprt
The number of 2MASS cross-correlated objects associated with the BMW-HRI X-ray source.

IRAS_Name
The cross-correlated IRAS Point Source Catalog (IRASPSC, CDS Catalog <II/125>) source name. See the Web URL http://space.gsfc.nasa.gov/astro/iras/psc.html for a description of this catalog. As the number of IRASPSC sources that cross-correlate with each BMW-HRI source can be, in several cases, more than one, the catalog authors decided to adopt the minimum distance approach. In this approach, all the IRASPSC parameters refer to the nearest IRASPSC source to the position of the BMW-HRI X-ray source.

IRAS_RA
The Right Ascension (J2000) of the cross-correlated IRASPSC source, in degrees.

IRAS_Dec
The Declination (J2000) of the cross-correlated IRASPSC source, in degrees.

IRAS_Flux_12um
The 12-micron, non-color-corrected flux density of the cross-correlated IRASPSC source, in Janskies.

IRAS_Flux_25um
The 25-micron, non-color-corrected flux density of the cross-correlated IRASPSC source, in Janskies.

IRAS_Flux_60um
The 60-micron, non-color-corrected flux density of the cross-correlated IRASPSC source, in Janskies.

IRAS_Flux_100um
The 100-micron, non-color-corrected flux density of the cross-correlated IRASPSC source, in Janskies.

IRAS_BMW_Offset
The angular distance between the IRASPSC source and the BMW-HRI X-ray source, in arcseconds.

IRAS_Num_Ctrprt
The number of IRASPSC cross-correlated objects associated with the BMW-HRI X-ray source.


Contact Person

Questions regarding the BMWHRICAT database table can be addressed to the HEASARC User Hotline.

Page Author: Browse Software Development Team
Last Modified: 8-Dec-2009