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Date and Time of the Query: 2018-12-11 T18:41:40 PST
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For refcode 1988AJ.....96...30C:
Retrieve 186 NED objects in this reference.
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Copyright by American Astronomical Society. Reproduced by permission
1988AJ.....96...30C RADIO IDENTIFICATIONS OF UGC GALAXIES: STARBURSTS AND MONSTERS J. J. CONDON National Radio Astronomy Observatory, Edgemont Road, Charlottesville, Virginia 22903-2475 J. J. BRODERICK Department of Physics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 Received 20 January 1988; revised 29 March 1988 ABSTRACT Radio identifications of galaxies in the Uppsala General Catalogue of Galaxies with {delta} < +82^deg^ were made from the Green Bank 1400 MHz sky maps. Every source having peak flux density S_P_ >= 150 mJy in the ~12 arcmin FWHM map point-source response and position < 5 arcmin in both coordinates from the optical position of any UGC galaxy was considered a candidate identification to ensure that very extended (up to 1 Mpc) and asymmetric sources would not be missed. Maps in the literature or new 1.49 GHz VLA C array maps made with 18 arcsec resolution were used to confirm or reject candidate identifications. The resulting list of 176 confirmed identifications should be complete, reliable, and suitable for statistical investigations of radio emission from nearby (D < 300 Mpc for H_0_ = 50 km s^-1^ Mpc^-1^) galaxies of all morphological types. The distribution of the infrared-radio parameter u=log (S_60 micron_/S_1400 MHz_) for most radio-selected spirals is roughly Gaussian with mean <u> = +2.02 +/- 0.02 and rms width {sigma}_u_ = 0.20. These values agree with <u> = +2.15 and {sigma}_u_ <= 0.3 found for infrared- selected galaxies since a difference {DELTA}u~(3/2) ln (10){sigma}^2^_u_ = 0.14 is expected from frequency selection alone. The small observed value of {DELTA}u implies that populations of radio-selected spiral galaxies are very similar to infrared-selected galaxies, not "normal" (optically selected) galaxies. Radio sources powered by "starbursts" can be effectively distinguished from those whose energy sources are "monsters" (e.g., super- massive black holes) by three radio and infrared criteria: ( 1) radio morphology, (2) u>= 1.6, and (3) infrared spectral index {alpha}_IR_=log (S_60 micron_/S_25 micron_)/log (60/25) >= +1.25.
Retrieve 186 NED objects in this reference.
Please click here for ADS abstract

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