EINSTEIN2E - Einstein Observatory 2E Catalog of IPC X-Ray Sources

Overview

This is the Einstein Observatory 2E Catalog of Imaging Proportional Counter (IPC) X-Ray Sources which was created by the HEASARC from the CDS Catalog IX/13. This latter catalog was prepared by the CDS in October 1996 based on the Einline version. It is similar to the HEASARC's IPC source catalog which the HEASARC created in the early 1990s directly based on Einstein Observatory Source Catalog tables obtained from the then-extant Astrophysics Data System distributed data archive. The IPC Catalog contains 6816 entries compared to 5948 entries in this catalog, notice.

This catalog contains sources with signal-to-noise values of 3.5 and greater from Einstein IPC observations. Note that a single source may have more than one entry in this catalog.

References

EINSTEIN Observatory catalog of IPC X-ray sources
    Harris D.E., Forman W, Gioa I.M., Hale J.A., Harnden Jr. F.R., Jones C.,
    Karakashian T., Maccacaro T., McSweeney J.D., Primnini F.A., Schwarz J.,
    Tananbaum H.D., Thurman J.
   <SAO HEAD CD-ROM Series I (Einstein), Nos 18-36 (1994)>

Provenance

This catalog was created by the HEASARC in November 2000 based on the CDS Catalog IX/13 file 2e.dat.

Parameters

Name
This is the 2E catalog source designation as created by the HEASARC, based on appending the 1950 coordinates to the "2E " prefix in the recommended IAU naming style, and as recognized by the Dictionary of Nomenclature of Celestial Objects.

Alt_Name
This the alternative 2E catalog source designation as created by the HEASARC, based on appending the 2E Catalog Number to the "2E " prefix. This alternate source naming convention is also recognized by the Dictionary of Nomenclature of Celestial Objects.

RA
The Right Ascension of the X-ray source in the selected equinox. This was given in 1950 coordinates to a precision of 0.1 seconds of time in the original CDS table.

Dec
The Declination of the X-ray source in the selected equinox. This was given in 1950 coordinates to a precision of 1 arcsecond in the original CDS table.

LII
The Galactic Longitude of the X-ray source.

BII
The Galactic Latitude of the X-ray source.

Catalog_Number
The 2E Catalog Number representing a unique source: note that a single source may have more than one entry in this catalog.

Sequence_Number
The Einstein Sequence Number (ESN) of the IPC observation in which the source was detected.

Field_Number
A running field number within a given IPC observation as identified by the Einstein Sequence Number. Each entry has a unique combination of sequence_number and field_number, therefore.

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

Count_Rate
The corrected count rate, in counts per second.

Count_Rate_Error
The error in the count rate, in counts per second.

Live_Time
The live time (essentially the exposure time) of the observations, in seconds, at the field center.

Net_Counts
The Net Counts in the source detect cell.

Background_Counts
The estimated background counts in the detect cell.

SNR
The signal-to-noise ratio (SNR) for the detection: only sources with signal-to-noise values of 3.5 or greater were included in this catalog.

Size_Corr
The size correction is a factor which serves to correct all intensity measurements (optimized for point sources) of resolved sources for the x-ray flux ignored by the detection box measurements. It is defined as the ratio of the intensity contained within the 3-sigma contour to the intensity within the detection box (2.4'x2.4'), the latter value corrected for the point response function and mirror scattering.

Rib_Edge_Code
The Ribs and Edges Code or RECO. This is a numeric flag with non-zero values indicating that the detection cell falls near or on a rib shadow or detector edge. The code contains two embedded numbers expressed in 4 digits: the first two (thousands and hundreds) give the total number (max # = 16) of frame subcells shadowed by the ribs or masked field edge; the last two (tens and units digits) give the total number of subcells (maximum = 09) within the detect box which are shadowed.

Off_Axis
The angular distance that the X-ray source is away from the field center, in arcminutes.

Source_Flags
A set of source flags coded as follows:

       A - additional detections of this source were achieved in other
           observations
       B - Probably should be paired with another detection; but separation
           exceeded cutoff and thus not assigned an "A" flag.
       H - a hardness ratio is available
       L - the source was detected only with the local detect method
       E - intensity corrected for source near the exposure cutoff at
           the field edge.
       I - source detected by local detect near a field edge. Intensity
           adjusted to remove redundant exposure corrections.

Reference_Flag
A reference and/or identification flag coded as follows:

       AGN     Active Galactic Nucleus
       BL      BL Lac object
       CLG     Cluster (or group) of galaxies
       CV      Cataclysmic Variable
       G       Galaxy
       GLB     Globular Cluster
       P       Pulsar
       Q       Quasar
       RS      Radio source
       S       Star
       SNR     Supernova Remnant
       SY      Seyfert Galaxy
       Y       Reference available, but no optical class
       +       Generic indicator which means possible ID lies from
               100-150 arcseconds from source location.

Contact Person

Questions regarding the EINSTEIN2E database table can be addressed to the HEASARC Help Desk.

Page Author: Browse Software Development Team
Last Modified: Monday, 16-Sep-2024 17:26:51 EDT