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IPCSLEW: Help

IPCSLEW - Einstein Catalog IPC Slew Survey


Overview

This database table contains the list of sources detected in the IPC Slew Survey. It was created in March 1992 and contains 819 entries.

The original IPC Slew Survey source list was released on CD-ROM and contained 1067 sources. The list was updated in 1991 to remedy a software bug which omitted a thin slice of RA near 24h; the bug fix yielded 8 additional sources, to bring the total to 1075. The list, however, was found to contain a large fraction (10 to 15 percent) of unreliable sources, especially those sources with <= 5 photons. The unreliable sources were rejected in producing the latest version of the source list, so that it now has an estimated false source rate of only 2 percent, and contains 256 fewer sources than the previous version.

The previous version of the source list, with 1075 sources, has been retained in a database called OLDIPCSLEW.


Catalog Bibcode

1992ApJS...80..257E

References

Elvis, M., Plummer, D., Schachter, J., and Fabbiano G. 1992, Ap.J. Supplement, in press (May issue).

Provenance

The HEASARC implemented this database table in March 1992.

Description

The Einstein IPC was left turned on during slews from one object to the next and so provided a limited survey of the sky. This database table is a catalog of the sources detected during this survey.

This source list is more compact than the previous versions, with fewer parameters. Each entry contains source names, coordinates, a count rate and associated errors, and an object classification.


Parameters

BII
The galactic latitude, calculated from the given RA and Dec.

Catalog_Designation
`Catalog Designation` is the 1ES name according to IAU convention.

Class
This is a 4-digit code, used by the BROWSE software, which indicates the object classification.

Count_Rate
`Count rate` is the IPC count rate for the source.

Count_Rate_Error
The count rate error did not originate in the original source list. It was derived by the HEASARC by averaging the sizes of the two error bars. It was necessary to add a database parameter called `count rate error` so that BROWSE can use it for plots. When creating plots, the BROWSE software sometimes uses a parameter called `xxxxx error`, where `xxxxx` is the parameter name, to draw symmetrical error bars around a quantity. Since BROWSE cannot plot asymmetrical error bars, it was decided that the positive and negative IPC count rate error bars could be averaged to create a `count rate error` parameter.

Cr_Error_Neg
`CR error neg` is the negative error bar for the count rate.

Cr_Error_Pos
`CR error pos` is the positive error bar for the count rate.

Dec
The centroid Declination.

LII
The galactic longitude, calculated from the given RA and Dec.

Name
`Name` is the source name from cross-correlations with optical catalogs.

Object_Type
`Object type` is a string indicating what type of object the source is. The object types are coded as follows:

   * AC     = active star
   * AGN    = active galactic nucleus
   * BL     = BL Lac object
   * CG     = cluster of galaxies
   * CV     = cataclysmic variable
   * GAL    = normal galaxy
   * P      = pulsar
   * S      = normal star
   * SNR    = supernova remnant
   * WD     = white dwarf
   * XRB    = X-ray binary
   * XRB-Be = X-ray binary with Be star secondary
  
The AGN, BL, CG, and GAL codes are often followed by a colon and then a redshift, while the star codes (S, AC, WD) are often followed by a colon and a stellar classification or white dwarf type.

RA
The centroid Right Ascension.


Contact Person

Questions regarding the IPCSLEW database table can be addressed to the HEASARC User Hotline.
If you have any problems, please consult the help page or mail ledas-help@star.le.ac.uk
 
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