Background and Motivation
We are re-analyzing archival data from the Parkes radio telescope to hunt for previously missed pulsars and fast radio bursts. The archival data is from a 70-cm survey (called PKS70) that was conducted at Parkes in the 1990's which covered much of the southern sky. This data was processed at the time it was taken, and a large number of pulsars were discovered and published.
We have reprocessed the raw data from the entire survey. There are two reasons for doing this reprocessing.
The first is that newer software we are using (PRESTO) is better tuned in some ways (better radio frequency interference excision, sensitivity to accelerated pulsars in binary systems) to find pulsars than the old software that was used all those years ago, so there may be pulsars lurking in the data that were missed.
The second is that with newer software we can search for radio bursts as well as periodicities. Impulsive signatures such as giant single pulses from neutron stars or fast radio bursts (FRBs) from distant galaxies that were previously undetected may now be discoverable. In particular, we are using the HEIMDALL single pulse detection package with the software package FETCH, a neural network classifier which is able to reliably identify realistic impulsive signals (and sift out likely interference signals).
Students working on the project look through standard prepfold search plots to look for pulsars. The pulsars found in the data are checked against the known pulsar catalog to see if it they are in fact new/undiscovered pulsars or not, and to make sure that all of the pulsars found in the original survey processing are seen again in the reprocessed data. In addition, students look through the single-pulse plots identified by FETCH as likely real to look for new signatures from burst sources.
Here are papers describing the original PKS70 survey:
Re-Analysis Status and Results
Four FRBs were found in the re-analysis of the PKS70 survey. These were published in "Four New Fast Radio Bursts Discovered in the Parkes 70-cm Pulsar Survey Archive" by F. Crawford et al., Monthly Notices of the Royal Astronomical Society, 515, 3698 (2022). See also the F&M FRB page.
Acknowledgment: This project includes archived data obtained through the Australia Telescope Online Archive and the CSIRO Data Access Portal (http://data.csiro.au). This research also used the Franklin and Marshall College compute cluster which was funded through NSF grant 1925192.