Diffuse X-Ray-emitting Gas in Major Mergers
Using archived data from the Chandra X-ray telescope, we have extracted the diffuse X-ray emission from 49 equal-mass interacting/merging galaxy pairs in a merger sequence, from widely separated pairs to merger remnants. After the removal of contributions from unresolved point sources, we compared t...
| Main Authors: | , , , , , , , |
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| Format: | Journal Article |
| Published: |
Institute of Physics Publishing
2018
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| Online Access: | http://hdl.handle.net/20.500.11937/66900 |
| _version_ | 1848761422631141376 |
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| author | Smith, B. Campbell, K. Struck, C. Soria, Roberto Swartz, D. Magno, M. Dunn, B. Giroux, M. |
| author_facet | Smith, B. Campbell, K. Struck, C. Soria, Roberto Swartz, D. Magno, M. Dunn, B. Giroux, M. |
| author_sort | Smith, B. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Using archived data from the Chandra X-ray telescope, we have extracted the diffuse X-ray emission from 49 equal-mass interacting/merging galaxy pairs in a merger sequence, from widely separated pairs to merger remnants. After the removal of contributions from unresolved point sources, we compared the diffuse thermal X-ray luminosity from hot gas (L X (gas)) with the global star formation rate (SFR). After correction for absorption within the target galaxy, we do not see a strong trend of L X (gas)/SFR with the SFR or merger stage for galaxies with SFR > 1 Myr -1 . For these galaxies, the median L X (gas)/SFR is 5.5 ×10 39 ((erg s -1 )/Myr -1 )), similar to that of normal spiral galaxies. These results suggest that stellar feedback in star-forming galaxies reaches an approximately steady-state condition, in which a relatively constant fraction of about 2% of the total energy output from supernovae and stellar winds is converted into X-ray flux. Three late-stage merger remnants with low SFRs and high K-band luminosities (L K ) have enhanced L X (gas)/SFR; their UV/IR/optical colors suggest that they are post-starburst galaxies, perhaps in the process of becoming ellipticals. Systems with L K < 10 10 L have lower L X (gas)/SFR ratios than the other galaxies in our sample, perhaps due to lower gravitational fields or lower metallicities. We see no relation between L X (gas)/SFR and Seyfert activity in this sample, suggesting that feedback from active galactic nuclei is not a major contributor to the hot gas in our sample galaxies. |
| first_indexed | 2025-11-14T10:31:25Z |
| format | Journal Article |
| id | curtin-20.500.11937-66900 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T10:31:25Z |
| publishDate | 2018 |
| publisher | Institute of Physics Publishing |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-669002018-09-28T00:19:26Z Diffuse X-Ray-emitting Gas in Major Mergers Smith, B. Campbell, K. Struck, C. Soria, Roberto Swartz, D. Magno, M. Dunn, B. Giroux, M. Using archived data from the Chandra X-ray telescope, we have extracted the diffuse X-ray emission from 49 equal-mass interacting/merging galaxy pairs in a merger sequence, from widely separated pairs to merger remnants. After the removal of contributions from unresolved point sources, we compared the diffuse thermal X-ray luminosity from hot gas (L X (gas)) with the global star formation rate (SFR). After correction for absorption within the target galaxy, we do not see a strong trend of L X (gas)/SFR with the SFR or merger stage for galaxies with SFR > 1 Myr -1 . For these galaxies, the median L X (gas)/SFR is 5.5 ×10 39 ((erg s -1 )/Myr -1 )), similar to that of normal spiral galaxies. These results suggest that stellar feedback in star-forming galaxies reaches an approximately steady-state condition, in which a relatively constant fraction of about 2% of the total energy output from supernovae and stellar winds is converted into X-ray flux. Three late-stage merger remnants with low SFRs and high K-band luminosities (L K ) have enhanced L X (gas)/SFR; their UV/IR/optical colors suggest that they are post-starburst galaxies, perhaps in the process of becoming ellipticals. Systems with L K < 10 10 L have lower L X (gas)/SFR ratios than the other galaxies in our sample, perhaps due to lower gravitational fields or lower metallicities. We see no relation between L X (gas)/SFR and Seyfert activity in this sample, suggesting that feedback from active galactic nuclei is not a major contributor to the hot gas in our sample galaxies. 2018 Journal Article http://hdl.handle.net/20.500.11937/66900 10.3847/1538-3881/aaa1a6 Institute of Physics Publishing fulltext |
| spellingShingle | Smith, B. Campbell, K. Struck, C. Soria, Roberto Swartz, D. Magno, M. Dunn, B. Giroux, M. Diffuse X-Ray-emitting Gas in Major Mergers |
| title | Diffuse X-Ray-emitting Gas in Major Mergers |
| title_full | Diffuse X-Ray-emitting Gas in Major Mergers |
| title_fullStr | Diffuse X-Ray-emitting Gas in Major Mergers |
| title_full_unstemmed | Diffuse X-Ray-emitting Gas in Major Mergers |
| title_short | Diffuse X-Ray-emitting Gas in Major Mergers |
| title_sort | diffuse x-ray-emitting gas in major mergers |
| url | http://hdl.handle.net/20.500.11937/66900 |