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M. A. Kitaeva

Publications and source records attributed to M. A. Kitaeva.

20 records · Page 2Linked to original sources

arXiv2022

Pushchino multibeam pulsar search -- II. Long-term variability of RRATs

Pulses from 16 previously known rotating radio transients (RRAT) have been searched at the 110 MHz daily monitor program for 4 to 5.5 years by using the Large-Phased-Array (LPA) at Pushchino. The total number of pulses detected in such a long observation interval is only 90 pulses for RRAT J0640+07 or is as high as 10,751 pulses for RRAT J0302+22. The number and amplitude of pulses varies at a time-scales from six to twenty months for RRATs J1336+33, J1404+11, J1848+15, J2051+12, J2105+22, and the pulse number can increase by one or two orders of magnitude in active phases. The long-term trends are found for RRATs J0139+33 and J0302+22, showing a 2-3 times increase in detected pulse number over 1,959 days. Some RRATs show the annual variations on both pulse number and pulse amplitude. It is hard to explain all these variation time scales by refractive scintillation on the interstellar medium. The annual and semi-annual variations are likely caused by scintillations of the inhomogeneous interplanetary plasma. Our data show that the number of observational sessions with no pulse detection over the threshold decreases exponentially with the length of pulse silence.

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arXiv2022

Investigation of four rotating radio transients properties at 111 MHz

The analysis of individual pulses of four rotating radio transients (RRATs), previously discovered in a monitoring survey running for 5.5 years at the frequency of 111 MHz, is presented. At a time interval equivalent to five days of continuous observations for each RRAT, 90, 389, 206, and 157 pulses were detected in J0640+07, J1005+30, J1132+25, and J1336+33, respectively. The investigated RRATs have a different distribution of the pulses amplitude. For J0640+07 and J1132+25, the distribution is described by a single exponent over the entire range of flux densities. For J1005+30 and J1336+33, it is a lognormal function with a power law tail. For J0640+07 and J1005+30, we have detected pulses with a signal-to-noise (S/N) ratio of few hundreds. For J1132+25 and J1336+33, the S/N of the strongest pulses reaches several tens. These RRATs show strong changing of character of emission. When strengths of pulse amplitudes significantly changed, we see long intervals of absence of emission or its strong attenuation. The analysis carried out in this work shows that it is possible that all the studied RRATs are, apparently, pulsars with giant pulses.

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