Multiwavelength study of Cygnus A III. Evidence for relic lobe plasma
We study the particle energy distribution in the cocoon surrounding Cygnus A, using radio images between 151 MHz and 15 GHz and a 200 ks Chandra ACIS-I image. We show that the excess low frequency emission in the the lobe further from Earth cannot be explained by absorption or excess adiabatic expan...
| المؤلفون الرئيسيون: | , , |
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| التنسيق: | Journal article |
| اللغة: | English |
| منشور في: |
2009
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| _version_ | 1826257401510100992 |
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| author | Steenbrugge, K Heywood, I Blundell, K |
| author_facet | Steenbrugge, K Heywood, I Blundell, K |
| author_sort | Steenbrugge, K |
| collection | OXFORD |
| description | We study the particle energy distribution in the cocoon surrounding Cygnus A, using radio images between 151 MHz and 15 GHz and a 200 ks Chandra ACIS-I image. We show that the excess low frequency emission in the the lobe further from Earth cannot be explained by absorption or excess adiabatic expansion of the lobe or a combination of both. We show that this excess emission is consistent with emission from a relic counterlobe and a relic counterjet that are being re-energized by compression from the current lobe. We detect hints of a relic hotspot at the end of the relic X-ray jet in the more distant lobe. We do not detect relic emission in the lobe nearer to Earth as expected from light travel-time effects assuming intrinsic symmetry. We determine that the duration of the previous jet activity phase was slightly less than that of the current jet-active phase. Further, we explain some features observed at 5 and 15 GHz as due to the presence of a relic jet. |
| first_indexed | 2024-03-06T18:17:37Z |
| format | Journal article |
| id | oxford-uuid:052990d2-4256-418e-8c9c-b992e01af8f0 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T18:17:37Z |
| publishDate | 2009 |
| record_format | dspace |
| spelling | oxford-uuid:052990d2-4256-418e-8c9c-b992e01af8f02022-03-26T08:55:36ZMultiwavelength study of Cygnus A III. Evidence for relic lobe plasmaJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:052990d2-4256-418e-8c9c-b992e01af8f0EnglishSymplectic Elements at Oxford2009Steenbrugge, KHeywood, IBlundell, KWe study the particle energy distribution in the cocoon surrounding Cygnus A, using radio images between 151 MHz and 15 GHz and a 200 ks Chandra ACIS-I image. We show that the excess low frequency emission in the the lobe further from Earth cannot be explained by absorption or excess adiabatic expansion of the lobe or a combination of both. We show that this excess emission is consistent with emission from a relic counterlobe and a relic counterjet that are being re-energized by compression from the current lobe. We detect hints of a relic hotspot at the end of the relic X-ray jet in the more distant lobe. We do not detect relic emission in the lobe nearer to Earth as expected from light travel-time effects assuming intrinsic symmetry. We determine that the duration of the previous jet activity phase was slightly less than that of the current jet-active phase. Further, we explain some features observed at 5 and 15 GHz as due to the presence of a relic jet. |
| spellingShingle | Steenbrugge, K Heywood, I Blundell, K Multiwavelength study of Cygnus A III. Evidence for relic lobe plasma |
| title | Multiwavelength study of Cygnus A III. Evidence for relic lobe plasma |
| title_full | Multiwavelength study of Cygnus A III. Evidence for relic lobe plasma |
| title_fullStr | Multiwavelength study of Cygnus A III. Evidence for relic lobe plasma |
| title_full_unstemmed | Multiwavelength study of Cygnus A III. Evidence for relic lobe plasma |
| title_short | Multiwavelength study of Cygnus A III. Evidence for relic lobe plasma |
| title_sort | multiwavelength study of cygnus a iii evidence for relic lobe plasma |
| work_keys_str_mv | AT steenbruggek multiwavelengthstudyofcygnusaiiievidenceforreliclobeplasma AT heywoodi multiwavelengthstudyofcygnusaiiievidenceforreliclobeplasma AT blundellk multiwavelengthstudyofcygnusaiiievidenceforreliclobeplasma |