Comparison of burst properties between FRB 20190520B and FRB 20121102A
Abstract
A comparative analysis of the individual bursts between FRB 20190520B and FRB 20121102A is presented by compiling a sample of bursts in multiple wavelengths. It is found that the peak frequency (νp) distribution of the bursts of FRB 20190520B illustrates four discrete peaks in ~1-6 GHz and their spectral width distribution can be fitted with a lognormal function peaking at 0.35 GHz. The discrete νp distribution and the narrow-banded spectral feature are analogous to FRB 20121102A. The burst duration of FRB 20190520B in the rest frame averages to 10.72 ms, longer than that of FRB 20121102A by a factor 3. The specific energy $\left(E_{\rm\mu_{\rm c}}\right)$ at 1.25 GHz of FRB 20190520B observed with the Five-hundred-meter Aperture Spherical Radio Telescope narrowly ranges in [0.4, 1] × 1038 erg, different from the bimodal $E_{\rm \mu _{\rm c}}$ distribution of FRB 20121102A. Assuming a Gaussian spectral profile of the bursts, our Monte Carlo simulation analysis suggests that a power law (PL) or a cut-off power-law (CPL) energy function can comparably reproduce the $E_{\rm \mu _{\rm c}}$ distribution of FRB 20190520B. The derived energy function index of the PL model is 4.46 ± 0.17, much steeper than that of FRB 20121102A ($1.82^{+0.10}_{-0.30}$ ). For the CPL model, we obtain an index of 0.47 and a cut-off energy of 7.4 × 1037 erg. Regarding the predicted νp distribution in 1-2 GHz, the CPL model is more preferred than the PL model. These results indicate that FRB 20190520B and FRB 20121102A share similar spectral properties, but their energy functions are intrinsically different.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- July 2023
- DOI:
- 10.1093/mnras/stad1271
- arXiv:
- arXiv:2305.02595
- Bibcode:
- 2023MNRAS.522.5600L
- Keywords:
-
- radio continuum: transients;
- fast radio bursts;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 2023,MNRAS in press, 12 pages, 7 figures