ALMA observations of 4U 1728 - 34 and 4U 1820 - 30: First detection of neutron star X-ray binaries at 300 GHz
We report on the first observations of neutron star low-mass X-ray binaries with the Atacama Large Millimeter/submillimeter Array (ALMA) at ~300 GHz. Quasi-simultaneous observations of 4U 1728-34 and 4U 1820-30 were performed at radio (ATCA), infrared (VLT) and X-ray (Swift) frequencies, spanning mo...
| Main Authors: | , , , , , |
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| Format: | Journal Article |
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EDP Sciences
2017
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| Online Access: | http://purl.org/au-research/grants/arc/FT140101082 http://hdl.handle.net/20.500.11937/52076 |
| _version_ | 1848758839355113472 |
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| author | Díaz Trigo, M. Migliari, S. Miller-Jones, James Rahoui, F. Russell, D. Tudor, V. |
| author_facet | Díaz Trigo, M. Migliari, S. Miller-Jones, James Rahoui, F. Russell, D. Tudor, V. |
| author_sort | Díaz Trigo, M. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | We report on the first observations of neutron star low-mass X-ray binaries with the Atacama Large Millimeter/submillimeter Array (ALMA) at ~300 GHz. Quasi-simultaneous observations of 4U 1728-34 and 4U 1820-30 were performed at radio (ATCA), infrared (VLT) and X-ray (Swift) frequencies, spanning more than eight decades in frequency coverage. Both sources are detected at high significance with ALMA. The spectral energy distribution of 4U 1728-34 is consistent with synchrotron emission from a jet with a break from optically thick to optically thin emission at 1.3-11.0 × 1013 Hz. This is the third time a jet spectral break has been reported for a neutron star X-ray binary. The radio to mm spectral energy distribution of 4U 1820-30 has significant detections at 5 and 300 GHz. This confirms the presence of radio emission during a soft state for this neutron star and represents the first detection of mm emission during such a state, unambiguously pointing to the presence of a jet. We also report on three additional unrelated sources - showing mm emission - in the ALMA fields of view of 4U 1728-34 and 4U 1820-30. © ESO, 2017. |
| first_indexed | 2025-11-14T09:50:22Z |
| format | Journal Article |
| id | curtin-20.500.11937-52076 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T09:50:22Z |
| publishDate | 2017 |
| publisher | EDP Sciences |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-520762022-11-23T06:22:30Z ALMA observations of 4U 1728 - 34 and 4U 1820 - 30: First detection of neutron star X-ray binaries at 300 GHz Díaz Trigo, M. Migliari, S. Miller-Jones, James Rahoui, F. Russell, D. Tudor, V. We report on the first observations of neutron star low-mass X-ray binaries with the Atacama Large Millimeter/submillimeter Array (ALMA) at ~300 GHz. Quasi-simultaneous observations of 4U 1728-34 and 4U 1820-30 were performed at radio (ATCA), infrared (VLT) and X-ray (Swift) frequencies, spanning more than eight decades in frequency coverage. Both sources are detected at high significance with ALMA. The spectral energy distribution of 4U 1728-34 is consistent with synchrotron emission from a jet with a break from optically thick to optically thin emission at 1.3-11.0 × 1013 Hz. This is the third time a jet spectral break has been reported for a neutron star X-ray binary. The radio to mm spectral energy distribution of 4U 1820-30 has significant detections at 5 and 300 GHz. This confirms the presence of radio emission during a soft state for this neutron star and represents the first detection of mm emission during such a state, unambiguously pointing to the presence of a jet. We also report on three additional unrelated sources - showing mm emission - in the ALMA fields of view of 4U 1728-34 and 4U 1820-30. © ESO, 2017. 2017 Journal Article http://hdl.handle.net/20.500.11937/52076 10.1051/0004-6361/201629472 http://purl.org/au-research/grants/arc/FT140101082 EDP Sciences fulltext |
| spellingShingle | Díaz Trigo, M. Migliari, S. Miller-Jones, James Rahoui, F. Russell, D. Tudor, V. ALMA observations of 4U 1728 - 34 and 4U 1820 - 30: First detection of neutron star X-ray binaries at 300 GHz |
| title | ALMA observations of 4U 1728 - 34 and 4U 1820 - 30: First detection of neutron star X-ray binaries at 300 GHz |
| title_full | ALMA observations of 4U 1728 - 34 and 4U 1820 - 30: First detection of neutron star X-ray binaries at 300 GHz |
| title_fullStr | ALMA observations of 4U 1728 - 34 and 4U 1820 - 30: First detection of neutron star X-ray binaries at 300 GHz |
| title_full_unstemmed | ALMA observations of 4U 1728 - 34 and 4U 1820 - 30: First detection of neutron star X-ray binaries at 300 GHz |
| title_short | ALMA observations of 4U 1728 - 34 and 4U 1820 - 30: First detection of neutron star X-ray binaries at 300 GHz |
| title_sort | alma observations of 4u 1728 - 34 and 4u 1820 - 30: first detection of neutron star x-ray binaries at 300 ghz |
| url | http://purl.org/au-research/grants/arc/FT140101082 http://hdl.handle.net/20.500.11937/52076 |