MAGPIS - Multi-Array Galactic Plane Imaging Survey

Overview

The Multi-Array Galactic Plane Imaging Survey (MAGPIS) maps portions of the first Galactic quadrant with an angular resolution, sensitivity, and dynamic range that surpass existing radio images of the Milky Way by more than an order of magnitude. The source detection threshold at 20 cm is in the range 1-2 mJy over the 85% of the survey region (Galactic longitudes from 5 to 32 degrees and Galactic latitudes within 0.8 degrees of the Galactic plane) not covered by bright extended emission; the angular resolution is ~6". Over 3000 discrete sources (diameters mostly <30") and ~400 diffuse emission regions are catalogued.

Additional information and data products, including full-resolution 20 cm images, complementary 90 cm images, regridded MSX 21 micron images, an image atlas of diffuse emission regions are available at the MAGPIS web site http://third.ucllnl.org/gps

Catalog Bibcode

2006AJ....131.2525H

References

MAGPIS: A Multi-Array Galactic Plane Imaging Survey
        Helfand D.J., Becker R.H., White R.L., Fallon A., Tuttle S.
       <Astron. J. 131, 2525 (2006)>
       =2006AJ....131.2525H

Provenance

This table was created by the HEASARC in June 2006 based on machine-readable versions of Tables 2 and 3 of the above reference which were obtained from the electronic Astronomical Journal web site.

Parameters

Name
The MAGPIS source designation recommended by the Dictionary of Nomenclature of Celestial Objects, using a naming convention based on the Galactic latitude and longitude of the radio source. Objects which were listed in Table 2 of the reference, i.e., the discrete sources, have been given a prefix of 'MAGPIS Discrete G', whereas objects from Table 3, the diffuse emission regions, have been given a prefix of 'MAGPIS Diffuse G'.

RA
The Right Ascension of the radio source in the selected equinox. This was calculated by the HEASARC from the Galactic latitude and longitude encoded in the name (and given to 5 decimal places) for the discrete sources, and from the Galactic latitude and longitude of the brightest pixel (given to 4 decimal places) for the diffuse emission regions. Notice that in the latter case, the position encoded in the name field and that of the brightest pixel are typically somewhat different.

Dec
The Declination of the radio source in the selected equinox. This was calculated by the HEASARC from the Galactic latitude and longitude encoded in the name (and given to 5 decimal places) for the discrete sources, and from the Galactic latitude and longitude of the brightest pixel (given to 4 decimal places) for the diffuse emission regions. Notice that in the latter case, the position encoded in the name field and that of the brightest pixel are typically somewhat different.

LII
The Galactic Longitude of the radio source.

BII
The Galactic Latitude of the radio source.

Flux_20_cm
The peak 20-cm flux density, in mJy/beam, of the radio source, as obtained from the Gaussian fit for the discrete sources, and for the brightest pixel value for the diffuse sources.

Int_Flux_20_cm
The integrated 20-cm flux density, in mJy, of the radio source, as obtained from the Gaussian fit for the discrete sources, and for the region within the source box (whose size is specified by the source_box_size parameter), but with the sum of the discrete sources that fall within the region subtracted out, for the diffuse sources.

Int_Flux_20_cm_Flag
This parameter is a flag which is set to a value of 'E' to indicate that the Gaussian model for a discrete source was inadequate and that the value is probably inaccurate.

Flux_20_cm_Error
The estimated RMS noise level at 20 cm (given only for the subset of discrete sources).

Major_Axis
The full width at half-maximum (FWHM) of the major axis of the elliptical Gaussian fit, in arcseconds (given only for the subset of discrete sources). The CLEAN beam (6.2" X 5.4") determines the size for unresolved sources.

Minor_Axis
The full width at half-maximum (FWHM) of the minor axis of the elliptical Gaussian fit, in arcseconds (given only for the subset of discrete sources). The CLEAN beam (6.2" X 5.4") determines the size for unresolved sources.

Position_Angle
The position angle of the major axis of the elliptical Gaussian fit, in degrees (given only for the subset of discrete sources).

Flux_8um_Limit
A limit flag for the 8 micron (um) flux density for sources which have matches in the MSX Point Source Catalog, Version 2.3. (given only for the subset of discrete sources).

Flux_8um
The 8 micron (um) flux density, in Janskies (Jy), for sources which have matches in the MSX Point Source Catalog, Version 2.3. (given only for the subset of discrete sources). The matching procedure to the MSXPSC is discussed in Section 5.1 of the MAGPIS reference.

Flux_21um_Limit
A limit flag for the 21 micron (um) flux density for sources which have matches in the MSX Point Source Catalog, Version 2.3. (given only for the subset of discrete sources).

Flux_21um
The 21 micron (um) flux density, in Janskies (Jy), for sources which have matches in the MSX Point Source Catalog, Version 2.3. (given only for the subset of discrete sources). The matching procedure to the MSXPSC is discussed in Section 5.1 of the MAGPIS reference.

Source_Box_Size
The size of the square box enclosing the diffuse source, in arcminutes.

Scaling_Factor
The intensity scaling factor for the diffuse emission region, used for display purposes in the diffuse source atlas available at the MAGPIS web site (http://third.ucllnl.org/gps/).

SNR_Names
This parameter (given only for the subset of diffuse sources) contains the name(s) of known supernova remnants.

Contact Person

Questions regarding the MAGPIS database table can be addressed to the HEASARC User Hotline.

Page Author: Browse Software Development Team
Last Modified: Friday, 30-Jun-2006 12:51:20 EDT