EINSTEIN2E - Einstein Observatory 2E Catalog of IPC X-Ray Sources
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 1990's
directly based on Einstein Observatory Source Catalog tables obtained via
the then-extant Astrophysics Data System distributed data archive. The IPC
Catalog contains 6816 entries compared to 5948 entries in this catalog,
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.
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)>
This catalog was created by the HEASARC in November 2000
based on the CDS Catalog IX/13.
This is the 2E Catalog Designation as created by the HEASARC based
on appending the 1950 Coordinates to the "2E " prefix in the recommended IAU
way, and as recognized by the Dictionary of Astronomical Nomenclature.
This the alternative 2E Catalog 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 Astronomical Nomenclature.
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.
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.
The Galactic Longitude of the X-ray source.
The Galactic Latitude of the X-ray source.
The 2E Catalog Number representing a unique source:
note that a single source may have more than one entry in this catalog.
The Einstein Sequence Number (ESN) of the IPC observation
in which the source was detected.
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.
The positional error radius of the X-ray source,
The corrected count rate, in counts per second.
The error in the count rate, in counts per second.
The live time (essentially the exposure time) of the
observations, in seconds, at the field center.
The Net Counts in the source detect cell.
The estimated background counts in the detect cell.
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
The Size Correction Factor. 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.
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.
The angular distance that the X-ray source is away from the
field center, in arcminutes.
A set of source flags coded as follows:
A - additional detections of this source were achieved in other
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.
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
GLB Globular Cluster
RS Radio source
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.
Questions regarding the EINSTEIN2E database table can be addressed to the
HEASARC User Hotline.
If you have any problems, please consult the help
page or mail firstname.lastname@example.org