The very high energy gamma ray burst GRB190114C as observed by MeerKAT
| dc.contributor.advisor | Woudt, Patrick | |
| dc.contributor.advisor | van der Horst, Alexander | |
| dc.contributor.author | Diretse, Reikantseone | |
| dc.date.accessioned | 2025-02-06T14:03:46Z | |
| dc.date.available | 2025-02-06T14:03:46Z | |
| dc.date.issued | 2024 | |
| dc.date.updated | 2025-02-06T14:00:58Z | |
| dc.description.abstract | We present the MeerKAT study of the highly energetic gamma ray burst (GRB), GRB190114C, which was the first GRB to have been recorded at teraelectronvolt (TeV) energies by the MAGIC telescope. We have observed this GRB with MeerKAT from as early as within the first day of the burst event, up to nearly a year at over 350 days. Our 13 epoch light curve is the most sampled radio light curve of this GRB at low frequencies (1.28 GHz) in comparison to published results. We detail the evolution of GRB190114C as a forward shock in a homogeneous medium for about 100 days post-burst, followed by a jet-break likely occurring simultaneously with the passage of the characteristic peak frequency across our observing band. We constrain the host galaxy component, and compare our modelled host value to fluxes extrapolated from pre-burst images of the field. As it is often for GRB observations at low radio frequencies, the evolution of GRB190114C is highly affected by strong interstellar scintillation, which we quantitatively constrain as long lasting refractive scattering. We then use the calculated scintillation parameters to put an upper limit on the radial size of the fireball, and compare this to other GRBs. Beyond the GRB, we take a commensal approach to study its intriguing and expansive background. We survey the field for potential radio transients or variables. We apply the LOFAR Transients Pipeline (TraP) in this pursuit. The pipeline has been adapted for MeerKAT data. We discover 11 potential transient or variable candidates. We detail their light curves, images, multi-wavelength counterparts and classifications to reveal their nature. We find that most of the candidates we find are likely active galactic nuclei (AGNs), and their variability in this context is reasonably due to interstellar scintillation as derived for the field | |
| dc.identifier.apacitation | Diretse, R. (2024). <i>The very high energy gamma ray burst GRB190114C as observed by MeerKAT</i>. (). University of Cape Town ,Faculty of Science ,Department of Astronomy. Retrieved from http://hdl.handle.net/11427/40882 | en_ZA |
| dc.identifier.chicagocitation | Diretse, Reikantseone. <i>"The very high energy gamma ray burst GRB190114C as observed by MeerKAT."</i> ., University of Cape Town ,Faculty of Science ,Department of Astronomy, 2024. http://hdl.handle.net/11427/40882 | en_ZA |
| dc.identifier.citation | Diretse, R. 2024. The very high energy gamma ray burst GRB190114C as observed by MeerKAT. . University of Cape Town ,Faculty of Science ,Department of Astronomy. http://hdl.handle.net/11427/40882 | en_ZA |
| dc.identifier.ris | TY - Thesis / Dissertation AU - Diretse, Reikantseone AB - We present the MeerKAT study of the highly energetic gamma ray burst (GRB), GRB190114C, which was the first GRB to have been recorded at teraelectronvolt (TeV) energies by the MAGIC telescope. We have observed this GRB with MeerKAT from as early as within the first day of the burst event, up to nearly a year at over 350 days. Our 13 epoch light curve is the most sampled radio light curve of this GRB at low frequencies (1.28 GHz) in comparison to published results. We detail the evolution of GRB190114C as a forward shock in a homogeneous medium for about 100 days post-burst, followed by a jet-break likely occurring simultaneously with the passage of the characteristic peak frequency across our observing band. We constrain the host galaxy component, and compare our modelled host value to fluxes extrapolated from pre-burst images of the field. As it is often for GRB observations at low radio frequencies, the evolution of GRB190114C is highly affected by strong interstellar scintillation, which we quantitatively constrain as long lasting refractive scattering. We then use the calculated scintillation parameters to put an upper limit on the radial size of the fireball, and compare this to other GRBs. Beyond the GRB, we take a commensal approach to study its intriguing and expansive background. We survey the field for potential radio transients or variables. We apply the LOFAR Transients Pipeline (TraP) in this pursuit. The pipeline has been adapted for MeerKAT data. We discover 11 potential transient or variable candidates. We detail their light curves, images, multi-wavelength counterparts and classifications to reveal their nature. We find that most of the candidates we find are likely active galactic nuclei (AGNs), and their variability in this context is reasonably due to interstellar scintillation as derived for the field DA - 2024 DB - OpenUCT DP - University of Cape Town KW - astronomy LK - https://open.uct.ac.za PB - University of Cape Town PY - 2024 T1 - The very high energy gamma ray burst GRB190114C as observed by MeerKAT TI - The very high energy gamma ray burst GRB190114C as observed by MeerKAT UR - http://hdl.handle.net/11427/40882 ER - | en_ZA |
| dc.identifier.uri | http://hdl.handle.net/11427/40882 | |
| dc.identifier.vancouvercitation | Diretse R. The very high energy gamma ray burst GRB190114C as observed by MeerKAT. []. University of Cape Town ,Faculty of Science ,Department of Astronomy, 2024 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/40882 | en_ZA |
| dc.language.rfc3066 | eng | |
| dc.publisher.department | Department of Astronomy | |
| dc.publisher.faculty | Faculty of Science | |
| dc.publisher.institution | University of Cape Town | |
| dc.subject | astronomy | |
| dc.title | The very high energy gamma ray burst GRB190114C as observed by MeerKAT | |
| dc.type | Thesis / Dissertation | |
| dc.type.qualificationlevel | Masters | |
| dc.type.qualificationlevel | MSc |