ICTS:32960

The discovery of two highly scattered FRBs with CRACO

(2025). The discovery of two highly scattered FRBs with CRACO. SciVideos. https://scivideos.org/index.php/icts-tifr/32960

The discovery of two highly scattered FRBs with CRACO. SciVideos, Oct. 13, 2025, https://scivideos.org/index.php/icts-tifr/32960 

          @misc{ scivideos_ICTS:32960,
            doi = {},
            url = {https://scivideos.org/index.php/icts-tifr/32960},
            author = {},
            keywords = {},
            language = {en},
            title = {The discovery of two highly scattered FRBs with CRACO},
            publisher = {},
            year = {2025},
            month = {oct},
            note = {ICTS:32960 see, \url{https://scivideos.org/index.php/icts-tifr/32960}}
          }
Joscha N. Jahns-Schindler
Talk numberICTS:32960
Source RepositoryICTS-TIFR

Abstract

CRACO is the new Commensal Realtime ASKAP Fast Transient COherent upgrade searching in the image domain for FRBs with an expected 5 times higher sensitivity than the incoherent sum survey. During commissioning, CRACO probed a new parameter space of long FRB durations from 14 ms to 110 ms time resolution. We found two slower FRBs at the high end of the search range. The detections demonstrate the presence of a detectable population of not-so-fast radio bursts at timescales of hundreds of milliseconds. The scattering times of ~70 ms and 700 ms at 0.8 GHz are among the highest observed so far. The second FRB also shows scintillation from the Milky Way restricting the scattering screen to be close to the source. These highly scattered events at moderate to low distances (z=0.3247 and 0.04973, respectively) extend the observed scattering timescales to 7 orders of magnitude. This extent together with the placement of one scattering screen in the host galaxy questions the applicability of a proposed scattering-distance relation. The vastly different estimated host dispersion measures of ~120 and ~220 pc/cm3 also question the transferability of the pulsar scattering-DM relationship to FRBs.