An Observational Study of Single Pulse of PSR J0835-4510

Abstract

Vela pulsar (PSR J0835-4510) was observed in L-band with the 40-meter radio telescope at the Haoping Observatory of National Time Service Center, Chinese Academy of Sciences. 38040 single pulses were detected in 56 minutes. The half-maximum line width ($W_{50}$) of these single pulses ranges from 0.52 to 3.3 ms, with an average value of 1.5 ms. This is smaller than that of the integral profile, which is 1.9 ms. The signal-noise ratio (S/N) of single pulses ranges from 6.8 to 495, with an average S/N value of 32.4. About 58% of the peak of single pulses arrived earlier than the peak of integral pulse profile, the earliest was 2.3 ms earlier. Lognormal distribution fits the radiation energy of single pulses with average $\mu$ $=-$0.02 and standard deviation $\sigma$ = 0.28. One normal single pulse was detected in the leading edge of the pulsar radiation window, with the S/N values of 47.4. There are 69 single pulses with S/N larger than 5 times the detected average S/N value of single pulses. These strong pulses are relatively narrow, and their $W_{50}$ ranges from 0.52 to 1.04 ms. These pulses are located near the rising edge of the average pulse profile. There are 23 single pulses detected with bimodal structure. The primary and secondary peaks are located in different radiation regions. It is found that the influences of strong single pulses and double peak single pulses on average pulse profile are different by studying the integral pulse profile of different types of single pulses.