Viewing Angle of Binary Neutron Star Mergers
© 2019 authors. Published by the American Physical Society. The joint detection of the gravitational wave (GW) GW170817 and its electromagnetic (EM) counterparts GRB170817A and kilonova AT 2017gfo has triggered extensive study of the EM emission of binary neutron star mergers. A parameter which is c...
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| Format: | Article |
| Language: | English |
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American Physical Society (APS)
2021
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| Online Access: | https://hdl.handle.net/1721.1/136425 |
| _version_ | 1826216660577550336 |
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| author | Chen, Hsin-Yu Vitale, Salvatore Narayan, Ramesh |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Chen, Hsin-Yu Vitale, Salvatore Narayan, Ramesh |
| author_sort | Chen, Hsin-Yu |
| collection | MIT |
| description | © 2019 authors. Published by the American Physical Society. The joint detection of the gravitational wave (GW) GW170817 and its electromagnetic (EM) counterparts GRB170817A and kilonova AT 2017gfo has triggered extensive study of the EM emission of binary neutron star mergers. A parameter which is common to and plays a key role in both the GW and the EM analyses is the viewing angle of the binary's orbit. If a binary is viewed from different angles, the amount of GW energy changes (implying that orientation and distance are correlated) and the EM signatures can vary, depending on the structure of the emission. Information about the viewing angle of the binary orbital plane is therefore crucial to the interpretation of both the GW and the EM data and can potentially be extracted from either side. In the first part of this study, we present a systematic analysis of how well the viewing angle of binary neutron stars can be measured from the GW data. We show that if the sky position and the redshift of the binary can be identified via the EM counterpart and an associated host galaxy, then for 50% of the systems the viewing angle can be constrained to ≤7° uncertainty from the GW data, independent of electromagnetic emission models. On the other hand, if no redshift measurement is available, the measurement of the viewing angle with GWs alone is not informative, unless the true viewing angle is close to 90°. This holds true even if the sky position is measured independently. Then, we consider the case where some constraints on the viewing angle can be placed from the EM data themselves. We show that the EM measurements can then be used in the analysis of GW data to improve the precision of the luminosity distance, and hence of the Hubble constant, by a factor of 2-3. |
| first_indexed | 2024-09-23T16:51:22Z |
| format | Article |
| id | mit-1721.1/136425 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T16:51:22Z |
| publishDate | 2021 |
| publisher | American Physical Society (APS) |
| record_format | dspace |
| spelling | mit-1721.1/1364252023-01-11T19:32:05Z Viewing Angle of Binary Neutron Star Mergers Chen, Hsin-Yu Vitale, Salvatore Narayan, Ramesh Massachusetts Institute of Technology. Department of Physics MIT Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology. Department of Physics © 2019 authors. Published by the American Physical Society. The joint detection of the gravitational wave (GW) GW170817 and its electromagnetic (EM) counterparts GRB170817A and kilonova AT 2017gfo has triggered extensive study of the EM emission of binary neutron star mergers. A parameter which is common to and plays a key role in both the GW and the EM analyses is the viewing angle of the binary's orbit. If a binary is viewed from different angles, the amount of GW energy changes (implying that orientation and distance are correlated) and the EM signatures can vary, depending on the structure of the emission. Information about the viewing angle of the binary orbital plane is therefore crucial to the interpretation of both the GW and the EM data and can potentially be extracted from either side. In the first part of this study, we present a systematic analysis of how well the viewing angle of binary neutron stars can be measured from the GW data. We show that if the sky position and the redshift of the binary can be identified via the EM counterpart and an associated host galaxy, then for 50% of the systems the viewing angle can be constrained to ≤7° uncertainty from the GW data, independent of electromagnetic emission models. On the other hand, if no redshift measurement is available, the measurement of the viewing angle with GWs alone is not informative, unless the true viewing angle is close to 90°. This holds true even if the sky position is measured independently. Then, we consider the case where some constraints on the viewing angle can be placed from the EM data themselves. We show that the EM measurements can then be used in the analysis of GW data to improve the precision of the luminosity distance, and hence of the Hubble constant, by a factor of 2-3. 2021-10-27T20:35:19Z 2021-10-27T20:35:19Z 2019 2021-07-08T17:55:45Z Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/136425 en 10.1103/PHYSREVX.9.031028 Physical Review X Creative Commons Attribution 4.0 International license https://creativecommons.org/licenses/by/4.0/ application/pdf American Physical Society (APS) APS |
| spellingShingle | Chen, Hsin-Yu Vitale, Salvatore Narayan, Ramesh Viewing Angle of Binary Neutron Star Mergers |
| title | Viewing Angle of Binary Neutron Star Mergers |
| title_full | Viewing Angle of Binary Neutron Star Mergers |
| title_fullStr | Viewing Angle of Binary Neutron Star Mergers |
| title_full_unstemmed | Viewing Angle of Binary Neutron Star Mergers |
| title_short | Viewing Angle of Binary Neutron Star Mergers |
| title_sort | viewing angle of binary neutron star mergers |
| url | https://hdl.handle.net/1721.1/136425 |
| work_keys_str_mv | AT chenhsinyu viewingangleofbinaryneutronstarmergers AT vitalesalvatore viewingangleofbinaryneutronstarmergers AT narayanramesh viewingangleofbinaryneutronstarmergers |