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arXiv · 2503.14030

Variations in the Radiation Intensity of Pulsar B0950+08: Nine Years of Monitoring at 110 MHz

T. V. Smirnova·M. O. Toropov·S. A. Tyul'bashev
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Abstract

The analysis of variations in the emission intensity of the pulsar B0950+08 from 2014 to 2022 with scales from minutes to years was carried out. The observations were obtained in a round-the-clock daily survey conducted on the Large Phased Array (LPA) radio telescope. The high variability of emission is shown not only from pulse to pulse, but also at scales greater than 3 min. The average value of the estimated amplitude of these variations in 3.2 minutes is 25~Jy, the modulation index is 1. The average relative amplitude of the interpulse (IP) is $2.00 \pm 0.28\%$ of the main pulse. In individual pulses, the amplitude of the interpulse may exceed the amplitude of the main pulse (MP), but this is a rare event. Emission is observed in almost the entire period of the pulsar. For the first time, the relative amplitude of emission between the main pulse and the interpulse (emission bridge) was measured. When averaging about 10 hours, it varies from $0.8\%$ to $1.31\%$ with an average value of $1.04 \pm 0.28\%$. A high correlation was found between MP and IP amplitude variations both when averaging profiles over 3.2 minutes and when averaging over years. This correlation is due to refractive interstellar scintillation. The frequency scale of IP diffraction interstellar scintillation was measured for the first time and it was shown that the spectral forms for IP and MP are well correlated and have the same frequency scale. There are strong variations in the frequency scale of scintillation $f_{dif}$ from session to session (time interval from one day) on scales of 200-800 kHz. The refractive scale of scintillation for 1-2 days has been determined. A modulation of emission with a characteristic scale of about 130 days was detected, which, apparently, is also associated with refractive scintillation.

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T. V. Smirnova, M. O. Toropov, S. A. Tyul'bashev. 2025-03-18. Variations in the Radiation Intensity of Pulsar B0950+08: Nine Years of Monitoring at 110 MHz. https://doi.org/10.1134/s1063772924700707

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