Contemporaneous optical-radio observations of a fast radio burst in a close galaxy pair

Journal Article · 16 February 2025 · Monthly Notices of the Royal Astronomical Society

DOI: https://doi.org/10.1093/mnras/staf289 · OSTI ID:2536749

Hanmer, K. Y. ; Pastor-Marazuela, I.; Brink, J.; Malesani, D. ; Stappers, B. W. ; Groot, P. J.; Cooper, A. J. ; Tejos, N.; Buckley, D. A. H.; Barr, E. D. ; Bezuidenhout, M. C. ; Bloemen, S.; Caleb, M.; Driessen, L. N. ; Fender, R.; Jankowski, F. ; Kramer, M. ; Pieterse, D. L. A.; Rajwade, K. M. ; Tian, J. ; Vreeswijk, P. M.; Wijnands, R.; Woudt, P. A.

ABSTRACT We present the MeerKAT discovery and MeerLICHT contemporaneous optical observations of the fast radio burst (FRB) 20230808F, which was found to have a dispersion measure of $$\mathrm{DM}=653.2\pm 0.4\mathrm{\, pc\, cm^{-3}}$$. FRB 20230808F has a scattering time-scale $$\tau _{s}=3.1\pm 0.1\, \mathrm{ms}$$ at 1563.6 MHz, a rotation measure $$\mathrm{RM}=169.4\pm 0.2\, \mathrm{rad\, m^{-2}}$$, and a radio fluence $$F_{\mathrm{radio}}=1.72\pm 0.01\, \mathrm{Jy\, ms}$$. We find no optical counterpart in the time immediately after the FRB, nor in the 3 months after the FRB during which we continued to monitor the field of the FRB. We set an optical upper flux limit in MeerLICHT’s q-band of $$11.7\, \mathrm{\mu Jy}$$ for a 60 s exposure which started $${\sim}3.4$$ s after the burst, which corresponds to an optical fluence, $$F_{\mathrm{opt}}$$, of $$0.039\, \mathrm{Jy\, ms}$$ on a time-scale of $${\sim}3.4$$ s. We obtain an estimate for the $q-$band luminosity limit of $$vL_{v}\sim 1.3\times 10^{43}\, \mathrm{erg\, s^{-1}}$$. We localize the burst to a close galaxy pair at a redshift of $$z_{\mathrm{spec}}=0.3472\pm 0.0002$$. Our time delay of $${\sim}3.4$$ s between the FRB arrival time and the start of our optical exposure is the shortest ever for an as yet non-repeating FRB, and hence the closest to simultaneous optical follow-up that exists for such an FRB.

• Sponsoring Organization: USDOE
• OSTI ID: 2536749
• Journal Information: Monthly Notices of the Royal Astronomical Society, Journal Name: Monthly Notices of the Royal Astronomical Society Journal Issue: 3 Vol. 538; ISSN 0035-8711
• Publisher: Oxford University PressCopyright Statement
• Country of Publication: United Kingdom
• Language: English