ROSPSPC - ROSAT Results Archive Sources for the PSPC

Overview

The ROSPSPC database table contains a list of sources detected by the Standard Analysis Software System (SASS) in public, unfiltered, pointed PSPC datasets. In addition to the parameters returned by SASS (like position, count rate, likelihood, etc.) each source in the table has associated with it a set of source and sequence "flags." These flags are provided by the ROSAT data centers in the US, Germany and the UK to help the user of the ROSPSPC database table quickly judge the reliability of a given source.

The ROSPSPC table excludes sources that meet the following parameter criteria: false_det = 'T' or deferred = 'T' or not_checked = 'T'. See the documentation below for descriptions of these parameters.

The catalog consists of all primary source parameters from the automated detection algorithm employed by the SASS. In addition each observation has been quality checked, both by automatic algorithms and by detailed visual inspection. The results of this quality checking are contained as a set of logical-value flags for a set of principal source parameters. If a source parameter is suspect, the associated flag is set to "TRUE"; parameters with no obvious problems maintain the default, "FALSE", value.

Catalog Bibcode

References

More information about the ROSAT mission and the SASS can be obtained from the ROSAT User Handbook, available at

   http://heasarc.gsfc.nasa.gov/docs/rosat/rosdocs.html

Provenance

This database table was last updated in August 2001. More information about the ROSAT Results Archive for PSPC sources can be obtained at the following web pages:

   http://heasarc.gsfc.nasa.gov/docs/rosat/rra/RRA.html
   http://hea-www.harvard.edu/rosat/rra.html
   http://www.aip.de/groups/xray/rosat/rra.html
   http://ledas-www.star.le.ac.uk/rra

Version

This catalog is the Second ROSAT Source Catalog of Pointed Observations with the Position Sensitive Proportional Counter (ROSPSPC / 2RXP), released on August 9, 2001. (See ROSAT NEWS No. 74 at http://heasarc.gsfc.nasa.gov/mail_archive/rosnews/msg00131.html for the official announcement.)

Flag Description

The following flags are used by the datacenters in constructing the ROSPSPC table. Flags are divided into "SEQUENCE FLAGS" which describe an entire data sequence, and "SOURCE FLAGS" which describe an individual detection. The PSPC source flags are associated with the primary SASS parameters like count rates, positions, etc., and with qualitative source characteristics.

All flags are LOGICAL, i.e. they have a value of TRUE or FALSE. A flag with a TRUE value indicates a possible problem with a source parameter. Thus, a source with no discernable problem would have all flags set to FALSE.

 Sequence flags:
 ===============

 FLAG NAME              "True" condition
 ---------               ----------------
 ASP_SUSP                obvious aspect problems (sources appear multiple or
                         have obvious ellipticity) (*)
 EXT_EMIS                presence of extended emission over most of the field
 FIELD_FDET              one or more detected sources deemed false
 DEFERRED                data screening not done
 MISS_SRC                one or more obvious sources not detected by SASS
 BKG_SUSP                field background may be incorrect (due to inclusion
                         of high background intervals or extended emission)
 SLIS_MIS                source list is missing (no sources detected by SASS or
                         source detection stopped)
 EXPO_MAP                the exposure map is not correct

 Source Flags:
 =============

 FLAG NAME              "True" condition
 ----------              ----------------
 CONFUSED                close sources confused detection algorithm
 DET_STRUCT              source near detector structure
 EXTENDED                source is probably resolved
 FALSE_DET               detection judged to be spurious
 INTEN_SUSP              source intensity suspect
 LTC_SUSP                source lightcurve may be suspect
 SPEC_SUSP               source spectrum suspect
 MULT_DET                complex emission split into individual sources
 NOT_CHECKED             source not checked visually by operator
 POS_SUSP                source position suspect (*)
 ASSOCIATED              another source nearby may influence derived source
                         quantities
 VARFLG_SUSP             SASS variability flag suspect
 WITHIN_EXT              source within extended emission

 (*) Note: The ASP_SUSP and POS_SUSP flags have been set for all observations
           after the loss of the second startracker on 1998-Apr-25.

Missed Sources

The Second ROSAT Pointed PSPC Source Catalog includes missing sources, i.e. obvious sources which were not detected by the SASS source detection software but which could be easily detected by visual inspection. Missed sources in the list are marked by negative values of their source identification numbers; i.e., the parameters 'SOLST_ID' and 'MPLSX_ID' are negative for these sources. The only tabulated quantities for these visually identified missed sources are source positions; other quantities (like count rates, hardness ratios, etc.) are not available.

Parameters

RA
Source Right Ascension

Dec
Source Declination

LII
Source Galactic Longitude

BII
Source Galactic Latitude

X
Unblocked x source position (0.5 arcsec/pixel)

Y
Unblocked y source position (0.5 arcsec/pixel)

XY_Error
Error in position (0.5 arcsec/pixel)

Im_X
Blocked x source position (15 arcsec/pixel)

Im_Y
Blocked y source position (15 arcsec/pixel)

Im_X_Error
Source X error in image pixels

Im_Y_Error
Source Y error in image pixels

Lev1_X
SASS level 1 x coordinate

Lev1_Y
SASS level 1 y coordinate

Offaxis
Off axis angle averaged over observation (arcmin)

Count_Rate
Source count rate from ML or MDETEC (cts/s), pha channel 11 to 235

Count_Rate_Error
Error of count rate (cts/s), pha channel 11 to 235

Background
Bkg surface countrate (cts/s/arcmin**2)

XY_Size
Source detect cell size (arcsec)

Exposure
Exposure live time (s)

ML_Like
Maximum likelihood from ML algorithm

Srcdist
Distance from source to nearest source (arcsec)

Ribdist
Distance from source to nearest rib (arcsec)

Extent
sigma of gaussian distribution fitted to data (arcsec)

Extentlik
Source likelihood of extent

Hardness_Ratio_1
Hardness ratio (B-A)/(B+A), where A = counts in PHA-channel 11-41 and B = counts in PHA-channel 52-201

Hardness_Ratio_1_Error
Error in hardness ratio 1

Hardness_Ratio_2
Hardness ratio (D-C)/(D+C), where C = counts in PHA-channel 52-90 and D = counts in PHA-channel 91-201

Hardness_Ratio_2_Error
Error in hardness ratio 2

Chipl
Reduced chi-square of power law fit

Chirs
Reduced chi-square of Raymond-Smith fit

Vignetting
Mean vignetting correction

Counts_A
Source net counts for PHA-channel 11-41

Counts_B
Source net counts for PHA-channel 52-201

Counts_C
Source net counts for PHA-channel 52-90

Counts_D
Source net counts for PHA-channel 91-201

Counts_A_Error
Error on source net counts for PHA-channel 11-41

Counts_B_Error
Error on source net counts for PHA-channel 52-201

Counts_C_Error
Error on source net counts for PHA-channel 52-90

Counts_D_Error
Error on source net counts for PHA-channel 91-201

Corr_Ribdist
corrected src-rib dist

Corr_SrcDist
corrected src-src dist

Md_Like
Source likelihood from the L/MDETECT algorithm

Extraction_Radius
Extraction radius in MAX LIKELIHOOD algorithm (?arcsec)

Begin_Date
Observation start date

End_Date
Observation finish date

ROR
ROSAT Observation Request number assigned to the observing program. Typically the target of each pointed observation will have a unique ROR number assigned to it.

MPLSX_ID
Source number from the merged source list (MPLSX)

SOLST_ID
Source number from the final source list (SOLST)

QC_Date
Date on which this particular observation was visually inspected (yymmdd)

SeqID
Rationalized Data Format root file name; changed 980403 from FNAME. An observing sequence consists of a number of files with names like SEQID_suffix.fits. For example, rp900176n00_bas.fits is the name of the "basic" events file for the pointing named by SEQID="rp900176n00".

ObsID
Observation ID used during SASS processing

Site
Processing Site (either MPE or GSFC)

Filter
Filter (either NONE or BORON); for the ROSPSPC table, FILTER="NONE" since all the filtered observations are listed in a separate table (ROSPSPCF)

Priority
Bit-encoded value which signifies in which band(s) the detection was made. A bit value = 1 means a detection, 0 means no detection. The bits are encoded as follows:

                    BIT             Type
                    00              LDETEC, broad band
                    01              LDETEC, soft band
                    02              LDETEC, hard band
                    03              MDETEC, broad band
                    04              MDETEC, soft band
                    05              MDETEC, hard band

Mdet
Flag set to Y if the counts(net_rt) from the MDETEC (maximum likelihood detection) algorithm rather than the LDETEC (Local detect) algorithm.

Csq_Flag
Variability flag from chi-square test

Ks_Flag
Variability flag from KS test

U_Flag
Variability flag from U test

Fft_Flag
Variability flag from FFT test

SrcFlags
Summary of source flags. This is a string of abbreviations for each source flag which is set to TRUE, and indicates a possible problem with the source. The abbreviations used are c=CONFUSED, d=DET_STRUCT, e=EXTENDED f=FALSE_DET, i=INTEN_SUSP,l=LTC_SUSP, s=SPEC_SUSP, m=MULT_DET, n=NOT_CHECKED, p=POS_SUSP,a=ASSOCIATED, v=VARFLG_SUSP, w=WITHIN_EXT.

Confused
Close sources confused detect

Det_Struct
Source near detector structure

Extended
Source extended

False_Det
False detection

Inten_Susp
Source brightness suspect

Spec_Susp
Source spectrum suspect

Ltc_Susp
Source lightcurve suspect

Mult_Det
Complex emission erroneously split into numerous point sources

Not_Checked
Source not checked

Pos_Susp
Source position suspect

Associated
Associated source nearby

Varflg_Susp
Source variability flag suspect

Within_Ext
Source within extended emission

SeqFlags
Summary of sequence flags. This is a string of abbreviations for each sequence flag which is set to TRUE, and indicates a possible problem with the sequence. The abbreviations used are A=ASP_SUSP, E=EXT_EMIS, F=FIELD_FDET, D=DEFERRED, M=MISS_SRC, B=BKG_SUSP, S=SLIS_MIS, X=EXPO_MAP.

Deferred
Sequence deferred

Asp_Susp
Possible aspect problems?

Bkg_Susp
Possible bkg problems?

Ext_Emis
Significant extended emission

Field_Fdet
False detections present

Src_Miss
Missed sources present

Slis_Mis
No source list available

Vary
Variability flag (see comments below)

Source_Name
Name of source, like: 2RXP J153127.5+312918)

Detection_Name
Name of detection, like: 1RXP J153127.5+312918)

Sequence_Detection_Name
Name of detection, like: 1rp200855n00.123

Comments
Source comments

QC_Name
Checker ID

QC_Site
Checker site

Contact Person

Questions regarding the ROSPSPC database table can be addressed to the HEASARC Help Desk.

Page Author: Browse Software Development Team
Last Modified: Monday, 16-Sep-2024 17:34:05 EDT