AMUSE-VIRGO. II. DOWN-SIZING IN BLACK HOLE ACCRETION
We complete the census of nuclear X-ray activity in 100 early-type Virgo galaxies observed by the Chandra X-ray Telescope as part of the AMUSE-Virgo survey, down to a (3σ) limiting luminosity of 3.7 × 10[superscript 38] erg s[superscript –1] over 0.5-7 keV. The stellar mass distribution of the targe...
| Main Authors: | , , , , , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
Institute of Physics/American Astronomical Society
2015
|
| Online Access: | http://hdl.handle.net/1721.1/95905 |
| _version_ | 1826200579449290752 |
|---|---|
| author | Gallo, Elena Treu, Tommaso Marshall, Philip J. Woo, Jong-Hak Leipski, Christian Antonucci, Robert |
| author2 | MIT Kavli Institute for Astrophysics and Space Research |
| author_facet | MIT Kavli Institute for Astrophysics and Space Research Gallo, Elena Treu, Tommaso Marshall, Philip J. Woo, Jong-Hak Leipski, Christian Antonucci, Robert |
| author_sort | Gallo, Elena |
| collection | MIT |
| description | We complete the census of nuclear X-ray activity in 100 early-type Virgo galaxies observed by the Chandra X-ray Telescope as part of the AMUSE-Virgo survey, down to a (3σ) limiting luminosity of 3.7 × 10[superscript 38] erg s[superscript –1] over 0.5-7 keV. The stellar mass distribution of the targeted sample, which is mostly composed of formally "inactive" galaxies, peaks below 10[superscript 10] M ☉, a regime where the very existence of nuclear supermassive black holes (SMBHs) is debated. Out of 100 objects, 32 show a nuclear X-ray source, including 6 hybrid nuclei which also host a massive nuclear cluster as visible from archival Hubble Space Telescope images. After carefully accounting for contamination from nuclear low-mass X-ray binaries based on the shape and normalization of their X-ray luminosity function (XLF), we conclude that between 24% and 34% of the galaxies in our sample host an X-ray active SMBH (at the 95% confidence level). This sets a firm lower limit to the black hole (BH) occupation fraction in nearby bulges within a cluster environment. The differential logarithmic XLF of active SMBHs scales with the X-ray luminosity as L X [superscript –0.4±0.1] up to 10[superscript 42] erg s[superscript –1]. At face value, the active fraction—down to our luminosity limit—is found to increase with host stellar mass. However, taking into account selection effects, we find that the average Eddington-scaled X-ray luminosity scales with BH mass as M BH -0.62 +0.13[over]-0.12, with an intrinsic scatter of 0.46+0.08[subscript –0.06 dex]. This finding can be interpreted as observational evidence for "down-sizing" of BH accretion in local early types, that is, low-mass BHs shine relatively closer to their Eddington limit than higher mass objects. As a consequence, the fraction of active galaxies, defined as those above a fixed X-ray Eddington ratio, decreases with increasing BH mass. |
| first_indexed | 2024-09-23T11:38:34Z |
| format | Article |
| id | mit-1721.1/95905 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T11:38:34Z |
| publishDate | 2015 |
| publisher | Institute of Physics/American Astronomical Society |
| record_format | dspace |
| spelling | mit-1721.1/959052022-10-01T04:57:45Z AMUSE-VIRGO. II. DOWN-SIZING IN BLACK HOLE ACCRETION Gallo, Elena Treu, Tommaso Marshall, Philip J. Woo, Jong-Hak Leipski, Christian Antonucci, Robert MIT Kavli Institute for Astrophysics and Space Research Gallo, Elena We complete the census of nuclear X-ray activity in 100 early-type Virgo galaxies observed by the Chandra X-ray Telescope as part of the AMUSE-Virgo survey, down to a (3σ) limiting luminosity of 3.7 × 10[superscript 38] erg s[superscript –1] over 0.5-7 keV. The stellar mass distribution of the targeted sample, which is mostly composed of formally "inactive" galaxies, peaks below 10[superscript 10] M ☉, a regime where the very existence of nuclear supermassive black holes (SMBHs) is debated. Out of 100 objects, 32 show a nuclear X-ray source, including 6 hybrid nuclei which also host a massive nuclear cluster as visible from archival Hubble Space Telescope images. After carefully accounting for contamination from nuclear low-mass X-ray binaries based on the shape and normalization of their X-ray luminosity function (XLF), we conclude that between 24% and 34% of the galaxies in our sample host an X-ray active SMBH (at the 95% confidence level). This sets a firm lower limit to the black hole (BH) occupation fraction in nearby bulges within a cluster environment. The differential logarithmic XLF of active SMBHs scales with the X-ray luminosity as L X [superscript –0.4±0.1] up to 10[superscript 42] erg s[superscript –1]. At face value, the active fraction—down to our luminosity limit—is found to increase with host stellar mass. However, taking into account selection effects, we find that the average Eddington-scaled X-ray luminosity scales with BH mass as M BH -0.62 +0.13[over]-0.12, with an intrinsic scatter of 0.46+0.08[subscript –0.06 dex]. This finding can be interpreted as observational evidence for "down-sizing" of BH accretion in local early types, that is, low-mass BHs shine relatively closer to their Eddington limit than higher mass objects. As a consequence, the fraction of active galaxies, defined as those above a fixed X-ray Eddington ratio, decreases with increasing BH mass. National Science Foundation (U.S.) (CAREER award NSF-0642621) Alfred P. Sloan Foundation (Sloan Research Fellowship) David & Lucile Packard Foundation (Fellowship) United States. National Aeronautics and Space Administration (Association of Universities for Research in Astronomy, Inc., NASA contract no. NAS5-26555) Space Telescope Science Institute (U.S.) (Hubble Postdoctoral Fellowship grant number HST-HF-01218.01-A ) 2015-03-06T16:48:02Z 2015-03-06T16:48:02Z 2010-05 2009-10 Article http://purl.org/eprint/type/JournalArticle 0004-637X 1538-4357 http://hdl.handle.net/1721.1/95905 Gallo, Elena, Tommaso Treu, Philip J. Marshall, Jong-Hak Woo, Christian Leipski, and Robert Antonucci. “AMUSE-VIRGO. II. DOWN-SIZING IN BLACK HOLE ACCRETION.” The Astrophysical Journal 714, no. 1 (April 6, 2010): 25–36. © 2009 American Astronomical Society. en_US http://dx.doi.org/10.1088/0004-637x/714/1/25 Astrophysical Journal Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf Institute of Physics/American Astronomical Society American Astronomical Society |
| spellingShingle | Gallo, Elena Treu, Tommaso Marshall, Philip J. Woo, Jong-Hak Leipski, Christian Antonucci, Robert AMUSE-VIRGO. II. DOWN-SIZING IN BLACK HOLE ACCRETION |
| title | AMUSE-VIRGO. II. DOWN-SIZING IN BLACK HOLE ACCRETION |
| title_full | AMUSE-VIRGO. II. DOWN-SIZING IN BLACK HOLE ACCRETION |
| title_fullStr | AMUSE-VIRGO. II. DOWN-SIZING IN BLACK HOLE ACCRETION |
| title_full_unstemmed | AMUSE-VIRGO. II. DOWN-SIZING IN BLACK HOLE ACCRETION |
| title_short | AMUSE-VIRGO. II. DOWN-SIZING IN BLACK HOLE ACCRETION |
| title_sort | amuse virgo ii down sizing in black hole accretion |
| url | http://hdl.handle.net/1721.1/95905 |
| work_keys_str_mv | AT galloelena amusevirgoiidownsizinginblackholeaccretion AT treutommaso amusevirgoiidownsizinginblackholeaccretion AT marshallphilipj amusevirgoiidownsizinginblackholeaccretion AT woojonghak amusevirgoiidownsizinginblackholeaccretion AT leipskichristian amusevirgoiidownsizinginblackholeaccretion AT antonuccirobert amusevirgoiidownsizinginblackholeaccretion |