1997/11/13 by I. Aretxaga, Itziar Aretxaga, R. J. Terlevich +2 · 24 citations
Physics and Astronomy · #Active galactic nucleus #Apparent magnitude #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Brightness #Galaxies: Formation, Evolution, Phenomena #Galaxy #Halo #Magnitude (astronomy) #QSOS #Redshift #Surface brightness #astro-ph
paper · pdf · doi:10.1046/j.1365-8711.1998.01398.x
published in Monthly Notices of the Royal Astronomical Society 296(3), 643-652 (Oxford University Press) · Accepted to be published in MNRAS. 11 pages, Latex, uses mn macros, also available at http://www.mpa-garching.mpg.de/~itziar
arxiv created 1997/11/13 · openalex publication_date 1998/05/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present multicolour images of the hosts of three z = 2 QSOs previously detected in the R band by our group. The luminosities, colours and sizes of the hosts overlap with those of actively star-forming galaxies in the nearby Universe. Surface brightness radial profiles over the outer resolved areas roughly follow either an r1/4 or an exponential law. These properties give support to the young host galaxy interpretation of the extended light around QSOs at high redshift. The rest-frame UV and UV-optical colours are inconsistent with the hypothesis of a scattered halo of light from the active nucleus by a simple optically thin scattering process produced by dust or hot electrons. If the UV light is indeed stellar, star formation rates of hundreds of solar masses per year are implied, an order of magnitude larger than in field galaxies at similar redshifts and above. This might indicate that the QSO phenomenon (at least the high-luminosity one) is preferentially accompanied by enhanced galactic activity at high redshifts.