G31.87+0.01

MAGPIS: What's New

2013 February 13

The APEX Telescope Large Area Survey of the Galaxy (ATLASGAL), a 870 µm survey of the Galactic Plane made using the LABOCA bolometer array at the APEX telescope in the Chilean Atacama Desert, has been added to the images included on the MAGPIS site. This covers the region

|b| < 1.5°    330° < l < 21°
The images have a pixel size of 6 arcsec, a resolution of 20" FWHM, and typical rms noise levels ranging from 40 to 50 mJy/beam.

2009 July 19

The Bolocam Galactic Plane Survey (BGPS), a 1.1 mm continuum survey of the Galactic Plane made using the Bolocam instrument on the Caltech Submillimeter Observatory, has been added to the images included in the MAGPIS site. This covers the region

|b| < 0.6°    349.4° < l < 90.5°
(There are additional images available from the BGPS web site covering a larger latitude range for a few fields in the outer Galaxy.) The images have a pixel size of 7.2 arcsec, a resolution of 33" FWHM, and typical rms noise levels ranging from 30 to 60 mJy/beam.

2008 July 9

A new page enabling the creation of multi-band color images is now available. Any of the twelve radio and infrared surveys can be used for the red, green, and blue channels of the image. The input images are resampled if necessary to match the highest resolution image being utilized.

This form can be accessed via a link on the usual single-band image cutout page.

2008 July 9

The MAGPIS database of high-dynamic range, high-sensitivity VLA images (Helfand et al., 2006, AJ, 131, 2525) has been extended. It now covers the region:

|b| < 0.8°  5° < l < 48.5°

2008 July 9

Our copy of the Spitzer Space Telescope Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) images has been updated to cover a larger sky area and to include all four GLIMPSE bands (3.6, 4.5, 5.8, and 8.0 µm). The sky area covered is now:

|b| < 1.0°  9.95° < l < 49.05°

As before, we have resampled the standard GLIMPSE images to match the New GPS 20 cm survey. That degrades the GLIMPSE resolution slightly (increasing the pixel size from 1.2 to 2.0 arcsec) but makes comparison with the radio images more straightforward.

2008 July 9

New 6 cm B-configuration images created from VLA archival data taken in 2005 and 2006 have been added. The 6cm Epoch 2 image images come from data acquired in March-May 2005 (program AH180). They cover the region:

|b| < 1.0°  28° < l < 33.5°

The 6cm Epoch 3 images come from data acquired in July-September 2006 (program AH884). They cover the region:

|b| < 1.2°  20.5° < l < 49.5°

Due to the way the data were collected, neither region is rectangular in Galactic coordinates. The images have a 0.5 arcsec pixel size. Note that the Epoch 2 data were reobserved for the Epoch 3 observations, and much of the Epoch 2 region was also observed for our 1994 6 cm survey.

2007 March 21

The catalogs from the reanalysis of the old 6 cm and 20 cm VLA radio surveys of the Galactic plane (White et al. 2005) have been updated. We recommend the new catalogs for all new projects, but the old catalogs are still available for ongoing projects.

The images have been coadded again to correct an error in the astrometry that could cause sources to be shifted by up to one pixel (1 to 1.5 arcseconds.) Most sources have smaller shifts, and many are hardly shifted at all. For the 20 cm catalog, the median position shift is 0.15 arcsec, and only 5% of sources are shifted by more than 1 arcsec. Where differences in positions exist, the new catalog is more accurate. For most uses the changes in the catalog are small.

As a result of small accompanying changes in peak flux densities, some sources in the previous catalog dropped below the detection threshold and do not appear in the new version (and vice versa.) This leads to changes in the source lists for each catalog at the detection limit.

2006 May 9

8 µm images taken with the Spitzer Space Telescope IRAC camera from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) project are now available through the image cutout server. We have resampled the standard GLIMPSE images to match the New GPS 20 cm survey. That degrades the GLIMPSE resolution slightly (increasing the pixel size from 1.2 to 2.0 arcsec) but makes comparison with the radio images more straightforward. The boundaries of the images are limited to the region of the northern Galactic plane currently released by the GLIMPSE project:

|b| < 1.0°  9.95° < l < 28.05°

2005 October 16

A new section of the website with catalogs and images from the Helfand et al. (2006) MAGPIS paper is now available. It is accessible through the Publications and Catalogs web pages.

2005 October 16

Maps derived from 90cm VLA archival data from Brogan et al. (2005, in preparation) and from our own observations have been added to the cutout image server. The region covered is

|b| < 2°    3.6° < l < 33.2°

The images have a pixel size of 6 arcsec over the range 3.6° < l < 20° (where they come from B+C+D-configuration archival data) and of 15 arcsec over the range 20° < l < 33° (where they come from our C-configuration observations).

2005 May 19

The catalogs and paper from the reanalysis of the old 6 cm and 20 cm VLA radio surveys of the Galactic plane have been updated. We recommend the new catalogs for all uses. The major change is reprocessing of a number of 20 cm fields to correct for the presence of OH maser emission lines in the bandpass.

2005 March 26

The web site has been redesigned and updated. We know that the web pages will no longer work well on Netscape4, but they should work and look better on most other browsers. Let us know of any serious problems.

2005 January 28

The Multi-Array Galactic Plane Imaging Survey website is online! Comments and suggestions are welcome.