Abstract I conducted a new search for dispersed radio pulses from the X-ray pulsar PSR J0537−6910 in the Large Magellanic Cloud (LMC) in a long (11.6 hr) archival 1.4 GHz Parkes search observation. I searched dispersion measures (DMs) between 0 and 10,000 pc cm−3and detected 49 pulses with a signal-to-noise ratio (S/N) greater than 7 at a wide range of DMs using the HEIMDALL and FETCH pulse detection and classification packages. All of the pulses were weak, with none having an S/N above 8.5. There was a significant excess of pulses observed in the DM range of the known pulsar population in the LMC, suggesting that these pulses may originate from LMC pulsars. Three repeat pulses, each having widths ≲1 ms, were detected in a single DM trial of 103.412 pc cm−3, which is in the LMC DM range. This is unlikely to occur by chance in a single DM trial in this search at the (marginally significant) 4.3σlevel. It remains unclear whether any of the detected pulses in the sample are from PSR J0537−6910 itself.
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No Dispersed Single Radio Pulses Detected in Archival Parkes Pulsar Observations Targeting Supernova Remnants and Anomalous X-Ray Pulsars
Abstract Four supernova remnants and four anomalous X-ray pulsars were previously observed with the Parkes telescope in a campaign to detect pulsed radio emission from associated neutron stars. No signals were detected in the original searches of these data. I have reprocessed the data with the more recently developed HEIMDALL and FETCH software packages, which are optimized for single-pulse detection and classification. In this new analysis, no astrophysical pulses were detected having a signal-to-noise ratio above 7 from any of the targets at dispersion measures ranging from 0 to 104pc cm−3. I include calculated fluence limits on single radio pulses from these targets.
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- Award ID(s):
- 2020265
- PAR ID:
- 10501160
- Publisher / Repository:
- Research Notes of the AAS
- Date Published:
- Journal Name:
- Research Notes of the AAS
- Volume:
- 7
- Issue:
- 11
- ISSN:
- 2515-5172
- Page Range / eLocation ID:
- 238
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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