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Дата изменения: Fri Apr 19 22:10:24 2002
Дата индексирования: Sat Mar 1 02:46:09 2014
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NVSS Source Search ($Revision: 1.6 $ - running v2.17)

NRAO/VLA Sky Survey

NVSS Source catalog browser

***Please read the important message below***

On 1 February 2002 this Mirror was upgraded from NVSSlist v2.10 to NVSSlist v2.17 . Please refer to the NVSSlist software changes log re two changes (concerning deconvolution algorithm and CLEAN bias correction) at v2.16 and upwards which may affect your results.

This form searches the source catalog produced by the NRAO/VLA Sky Survey (NVSS). This radio survey uses the NRAO Very Large Array telescope and will cover the sky north of a declination of -40 degrees at a frequency of 1.4 GHz, a resolution of 45" and a limiting peak source brightness of about 2.5 mJy/beam. Linear polarization as well as total intensity measurments are made. The survey is now substantially complete with only a few remaining holes. For detailed general instructions click here or for more about a form entry click on its label.

Equinox:
Sizes:
Minimum peak flux density (mJy):
Minimum percentage polarization:

Single position to search
Object name [optional]:
Central Right Ascension:
Central declination:
(Note: be sure to include seconds in position.)
Search radius and verification halfwidth in arcseconds [Optional]:
(Note: there is a limit of 50 pages.)		   

List of positions to search
Enter a list of positions to search:
Each line should have, in order, RA (hh mm ss.s), Dec (dd mm ss.s), an optional search radius in arcseconds (default 15"), an optional verification halfwidth (no default), and an optional field label. For example:
12 34 56.78 -00 12 34.5 15 720 My Star
 (Clears EVERYTHING!)

For more details on the probability of the chance coincidence of an NVSS source within a given radius of an arbitrary position look here.

In publications using NVSS results please reference Condon, et al. 1998, AJ, 115, 1693; a preprint of this paper which describes the design and techniques of the NVSS is available here. The contents of the NVSS source catalog and the techniques used by NVSSlist to derive error estimates and other parameters are described here. . For very extensive searches or listing of large amounts of the catalog it may be best to obtain your own copy of the catalog (about 150 MByte) and the browsing software For the latest information and detailed descriptions of the NVSS survey see its main site home page. Entire 4 x 4 degree fields may be obtained as FITS files using either a Web browser or ftp.

(Reminder: shift-click will generally force your browser to save the requested image to a file rather than displaying it in a text window.) A postage stamp server which returns FITS or jpeg files of limited regions from NVSS images is also available.

Users of the AIPS task IMAGR often need to image extra fields covering nearby confusing sources. A RUN file generator produces the required list of field offsets for NVSS sources whose flux densities, attenuated by the primary beam, exceed a chosen cutoff.

The (USA) National Radio Astronomy Observatory (NRAO) is operated by Associated Universities, Inc. and is a Facility of the (USA) National Science Foundation.

Any problems with the UK server?

segh@mrao.cam.ac.uk