Detection Statistics of Pulse Signals at Declinations from $+42^o$ to $+52^o$ at the Frequency 111 MHz

TL;DR

This study conducted a pulse signal search at declinations +42° to +52° at 111 MHz, detecting pulsar-like pulses, RRATs, and analyzing their dispersion measures, with findings on pulse rates, characteristics, and upper period estimates.

Contribution

It presents new observational data on pulse signals in a previously unmonitored sky region at 111 MHz, including detection of RRATs and analysis of their properties.

Findings

Average of 4 pulses per hour per beam

18.3% pulses similar to pulsars with dispersion shifts

Detection of 13 pulses from 4 RRATs with flux densities of 2-4 mJy

Abstract

A search for pulse signals was carried out in a new sky area included in the monitoring program for the search for pulsars and transients. Processing of several months data recorded in six frequency channels with a total bandwidth of 2.5 MHz showed that, on average, 4 pulses per hour are observed in each of the 24 connected stationary beams. Of these pulses, 18.3% are similar to those of pulsars. They are visible in one or two neighboring beams and have a pronounced dispersion shift, that is, they are recorded first at a high and then at a low frequency, which indicates the possible passage of the signal through the interstellar medium. Almost 68% of such detected pulses belong to six known pulsars with dispersion measures from 9 to 141 $pc/cm^3$, and almost all of the remaining pulses are either noise of an unknown nature or artifacts of the proposed pulse separation technique. An additional study of the selected array of 3650 obvious pulsar pulses revealed 13 pulses belonging to four rotating radio transients (RRATs). Their dispersion measures are in the range of 17-51 $pc/cm^3$. A search for regular (periodic) RRAT emission was carried out using power spectra summed over 121 days. Periodic radiation was not detected, but for two RRATs, upper estimates of the periods were obtained from measurements of the time intervals between pulses. The upper estimates of the integrated flux density of the detected RRATs are in the range 2-4 mJy at the frequency 111 MHz.