Abstract
Localization of fast radio bursts (FRBs) to arcsecond and subarcsecond precision maximizes their potential as cosmological probes. To that end, FRB detection instruments are deploying triggered complex-voltage capture systems to localize FRBs, identify their host galaxy, and measure a redshift. Here, we report the discovery and localization of two FRBs (20220717A and 20220905A) that were captured by the transient buffer system deployed by the MeerTRAP instrument at the MeerKAT telescope in South Africa. We were able to localize the FRBs to precision of ∼1 arcsecond that allowed us to unambiguously identify the host galaxy for FRB 20220717A (posterior probability ∼0.97). FRB 20220905A lies in a crowded region of the sky with a tentative identification of a host galaxy but the faintness and the difficulty in obtaining an optical spectrum preclude a conclusive association. The bursts show low linear polarization fractions (10-17 per cent) that conform to the large diversity in the polarization fraction observed in apparently non-repeating FRBs akin to single pulses from neutron stars. We also show that the host galaxy of FRB 20220717A contributes roughly 15 per cent of the total dispersion measure (DM), indicating that it is located in a plasma-rich part of the host galaxy which can explain the large rotation measure. The scattering in FRB 20220717A can be mostly attributed to the host galaxy and the intervening medium and is consistent with what is seen in the wider FRB population.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 3881-3892 |
| Number of pages | 12 |
| Journal | Monthly Notices of the Royal Astronomical Society |
| Volume | 532 |
| Issue number | 4 |
| DOIs | |
| State | Published - Aug 1 2024 |
Funding
The authors would like to thank the referee for their comments that significantly improved the manuscript. The MeerKAT telescope is operated by the South African Radio Astronomy Observatory, which is a facility of the National Research Foundation, an agency of the Department of Science and Innovation (DSI). The MeerTRAP collaboration would like to thank the MeerKAT Large Survey Project teams for allowing MeerTRAP to observe commensally. The MeerTRAP collaboration acknowledges funding from the European Research Council (ERC) under the European Union\u2019s Horizon 2020 research and innovation programme (grant agreement no. 694745). The authors also acknowledge the usage of TRAPUM infrastructure funded and installed by the Max-Planck-Institut f\u00FCr Radioastronomie and the Max-Planck-Gesellschaft. KMR would like to thank Mattieu DeVilliers and Ludwig Schwarz for useful discussions regarding off-boresight polarization calibration for MeerKAT. The authors would like to thank the South African Radio Astronomy Observatory (SARAO) for immense support during the commissioning of the transient buffer mode. KMR acknowledges support from the Vici research programme \u2018ARGO\u2019 with project number 639.043.815, financed by the Dutch Research Council (NWO). AM acknowledges support from the U.S. National Science Foundation through grant AST-2206492 and from the Nantucket Maria Mitchell Association. MC acknowledges support of an Australian Research Council Discovery Early Career Research Award (project number DE220100819) funded by the Australian Government. MB acknowledges support from the Bundesministerium f\u00FCr Bildung und Forschung(BMBF) D-MeerKAT award 05A17VH3 (Verbundprojekt D-MeerKAT). The authors would like to thank the referee for their comments that significantly improved the manuscript. The MeerKAT telescope is operated by the South African Radio Astronomy Observatory, which is a facility of the National Research Foundation, an agency of the Department of Science and Innovation (DSD. The MeerTRAP collaboration would like to thank the MeerKAT Large Survey Project teams for allowing MeerTRAP to observe commensally. The MeerTRAP collaboration acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement no. 694745). The authors also acknowledge the usage of TRAPUM infrastructure funded and installed by the Max-Planck-Institut fur Radioastronomie and the Max-Planck-Gesellschaft. KMR would like to thank Mattieu DeVilliers and Ludwig Schwarz for useful discussions regarding off-boresight polarization calibration for MeerKAT. The authors would like to thank the South African Radio Astronomy Observatory (SARAO) for immense support during the commissioning of the transient buffer mode. KMR acknowledges support from the Vici research programme 'ARGO' with project number 639.043.815, financed by the Dutch Research Council (NWO). AM acknowl- edges support from the U.S. National Science Foundation through grant AST-2206492 and from the Nantucket Maria Mitchell As- sociation. MC acknowledges support of an Australian Research Council Discovery Early Career Research Award (project number DE2201008I9) funded by the Australian Government. MB ac- knowledges support from the Bundesministerium fur Bildung und Forschung(BMBF) D-MeerK AT award 05 AI7VH3 (Verbundprojekt D-MeerKAT).
Keywords
- radio continuum: transients
- stars: neutron
- techniques: interferometric
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science