IPCSLEW - Einstein Catalog IPC Slew Survey
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
The previous version of the source list, with 1075 sources, has been retained
in a database called OLDIPCSLEW.
Elvis, M., Plummer, D., Schachter, J., and Fabbiano G. 1992, Ap.J. Supplement,
in press (May issue).
The HEASARC implemented this database table in March 1992.
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.
The galactic latitude, calculated from the given RA and Dec.
`Catalog Designation` is the 1ES name according to IAU convention.
This is a 4-digit code, used by the BROWSE software, which indicates the object
`Count rate` is the IPC count rate for the source.
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`
`CR error neg` is the negative error bar for the count rate.
`CR error pos` is the positive error bar for the count rate.
The centroid Declination.
The galactic longitude, calculated from the given RA and Dec.
`Name` is the source name from cross-correlations with optical catalogs.
`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.
The centroid Right Ascension.
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 firstname.lastname@example.org