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http://hdl.handle.net/2289/1423
Title: | VLA observations of 1E 1740.7-2942 - A search for radio recombination lines of positronium |
Authors: | Anantharamaiah, K.R. Dwarakanath, K.S. Morris, D. Goss, W.M. Radhakrishnan, V. |
Keywords: | POSITRONIUM RADIO SPECTRA RECOMBINATION REACTIONS VERY LARGE ARRAY (VLA) X RAY SOURCES GALACTIC NUCLEI MILKY WAY GALAXY |
Issue Date: | Jun-1993 |
Publisher: | The University of Chicago Press for the American Astronomical Society |
Citation: | Astrophysical Journal, 1993, Vol.410, p110-115 |
Abstract: | We have searched for the Ps87-alpha recombination line of positronium at the position of the Einstein X-ray source 1E 1740.7-2942 which has been identified as a strong source of time-variable annihilation line radiation. No line was detected with a 3 sigma upper limit of 330 microJy for a line width of 23.5 MHz, the expected width if the temperature of the annihilation region is about 7 x 10 exp 4 K. A continuum image of the field made from the same data shows, within the 90 percent confidence error circle of the X-ray source, a weak radio source with a core and lobe structure similar to extragalactic double radio sources. Comparison with other observations shows that the radio flux density of the core at 6 cm had increased by a factor of about 2.6 between 1991 October 7 and November 16 and has been decreasing steadily since then. We have explored some possible relations between the radio source and the X-ray source. We find that the radio and the X-ray sources could well be associated with each other. The nature of this source is uncertain - it could be either Galactic or extragalactic. In either case this source is a unique object. |
URI: | http://hdl.handle.net/2289/1423 |
ISSN: | 0004-637X 1538-4357 (online) |
Alternative Location: | http://adsabs.harvard.edu/cgi-bin/bib_query?1993ApJ...410..110A |
Copyright: | (1993) by the American Astronomical Society. Scanned images provided by the NASA ADS Data System. |
Appears in Collections: | Research Papers (A&A) |
Files in This Item:
File | Description | Size | Format | |
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1993 ApJ V410 p110.pdf | 6p. | 1.21 MB | Adobe PDF | View/Open |
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