DSA-10: a prototype array for localizing fast radio bursts
ABSTRACT The Deep Synoptic Array 10-dish prototype (DSA-10) is an instrument designed to detect and localize fast radio bursts with arcsecond accuracy in real time. Deployed at Owens Valley Radio Observatory, it consists of ten 4.5-m diameter dishes, equipped with a 250-MHz bandwidth dual polarization receiver, centred at 1.4 GHz. The 20 input signals are digitized and field programmable gate arrays are used to transform the data to the frequency domain and transmit it over ethernet. A series of computer servers buffer both raw data samples and perform a real time search for fast radio bursts on the incoherent sum of all inputs. If a pulse is detected, the raw data surrounding the pulse are written to disc for coherent processing and imaging. The prototype system was operational from 2017 June to 2018 February conducting a drift scan search. Giant pulses from the Crab Pulsar were used to test the detection and imaging pipelines. The 10-dish prototype system was brought online again in 2019 March, and will gradually be replaced with the new DSA-110, a 110-dish system, over the next 2 yr to improve sensitivity and localization accuracy.
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Award ID(s):
Publication Date:
NSF-PAR ID:
10189318
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
489
Issue:
1
Page Range or eLocation-ID:
919 to 927
ISSN:
0035-8711
1. ABSTRACT The origin of fast radio bursts (FRBs) still remains a mystery, even with the increased number of discoveries in the last 3 yr. Growing evidence suggests that some FRBs may originate from magnetars. Large, single-dish telescopes such as Arecibo Observatory (AO) and Green Bank Telescope (GBT) have the sensitivity to detect FRB 121102-like bursts at gigaparsec distances. Here, we present searches using AO and GBT that aimed to find potential radio bursts at 11 sites of past gamma-ray bursts that show evidence for the birth of a magnetar. We also performed a search towards GW170817, which has a merger remnant whose nature remains uncertain. We place $10\sigma$ fluence upper limits of ≈0.036 Jy ms at 1.4 GHz and ≈0.063 Jy ms at 4.5 GHz for the AO data and fluence upper limits of ≈0.085 Jy ms at 1.4 GHz and ≈0.098 Jy ms at 1.9 GHz for the GBT data, for a maximum pulse width of ≈42 ms. The AO observations had sufficient sensitivity to detect any FRB of similar luminosity to the one recently detected from the Galactic magnetar SGR 1935+2154. Assuming a Schechter function for the luminosity function of FRBs, we find that our non-detections favour a steep power-law index (α ≲ −1.1) and a large cut-off luminositymore »