Advanced search
Start date
Related content
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)


Full text
O'Sullivan, E. [1] ; Zezas, A. [1, 2, 3] ; Vrtilek, J. M. [1] ; Giacintucci, S. [4, 5] ; Trevisan, M. [6] ; David, L. P. [1] ; Ponman, T. J. [7] ; Mamon, G. A. [8, 9] ; Raychaudhury, S. [7, 10]
Total Authors: 9
[1] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 - USA
[2] Univ Crete, Dept Phys, GR-71003 Iraklion, Crete - Greece
[3] Univ Crete, Inst Theoret & Computat Phys, GR-71003 Iraklion, Crete - Greece
[4] Univ Maryland, Dept Astron, College Pk, MD 20742 - USA
[5] Univ Maryland, Joint Space Sci Inst, College Pk, MD 20742 - USA
[6] Inst Nacl Pesquisas Espaciais, BR-12227010 Sao Jose Dos Campos - Brazil
[7] Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands - England
[8] CNRS, UMR 7095, Inst Astrophys Paris, F-75014 Paris - France
[9] UMPC, F-75014 Paris - France
[10] Presidency Univ, Dept Phys, Kolkata 700073 - India
Total Affiliations: 10
Document type: Journal article
Source: ASTROPHYSICAL JOURNAL; v. 793, n. 2 OCT 1 2014.
Web of Science Citations: 7

We present new, deep Chandra X-ray and Giant Metrewave Radio Telescope 610 MHz observations of the spiral-galaxy-rich compact group HCG 16, which we use to examine nuclear activity, star formation, and high-luminosity X-ray binary populations in the major galaxies. We confirm the presence of obscured active nuclei in NGC 833 and NGC 835, and identify a previously unrecognized nuclear source in NGC 838. All three nuclei are variable on timescales of months to years, and for NGC 833 and NGC 835 this is most likely caused by changes in accretion rate. The deep Chandra observations allow us to detect for the first time an Fe K alpha emission line in the spectrum of the Seyfert 2 nucleus of NGC 835. We find that NGC 838 and NGC 839 are both starburst-dominated systems, with only weak nuclear activity, in agreement with previous optical studies. We estimate the star formation rates in the two galaxies from their X-ray and radio emission, and compare these results with estimates from the infrared and ultraviolet bands to confirm that star formation in both galaxies is probably declining after galaxy-wide starbursts were triggered similar to 400-500 Myr ago. We examine the physical properties of their galactic superwinds, and find that both have temperatures of similar to 0.8 keV. We also examine the X-ray and radio properties of NGC 848, the fifth largest galaxy in the group, and show that it is dominated by emission from its starburst. (AU)

FAPESP's process: 12/05142-5 - Assembling Baryons to Dark Halos: Stellar Content and the Star Formation History of Early-­type Galaxies
Grantee:Marina Trevisan
Support type: Scholarships in Brazil - Post-Doctorate