Tomasz Nowakowski is a writer for Phys.org.
The Chinese have detected quasi-periodic oscillation from the source of the historical light curve of blazar. A paper published May 5 on arXiv.org could shed more light on the nature and behavior of this blazar.
There are quasars at the centers of active, giant elliptical galaxies. They are part of a larger group of active galaxies that host active galactic nuclei. Their characteristic features are jets pointing towards the Earth.
Astronomers divide blazars into two classes based on their optical emission properties: flat-spectrum radio quasars that feature prominent and broad optical emission lines, and BL Lacs that do not.
The behavior of X-ray light when it flickers about certain frequencies is known as quasi-periodic oscillations. Many questions about the phenomenon of QPOs remain unanswered, but it is believed that they occur when X-rays are emitted near the inner edge of an accretion disk in which gas swirls onto a compact object.
The emission from blazars has also been observed with QPOs. The data from the Large Area Telescope (LAT) has led to the reporting of more than 20 QPOs in more than 20 blazars. It is important to detect new blazars that exhibit the same type of oscillations in the gamma-ray regime as the cause of the QPOs is still unclear.
A team of astronomer led by Yunlu Gong of Yunnan University in China has reported the finding of quasi-period behavior in the 4FGL J0407.0-3826), based on the LAT data.
The long-term data of blazar PKS 0405-385 was analyzed and found to have a highly probable quasi-periodic behavior.
The team decided to use the periodic timescale of approximately 2.8 years as the nal result, because the temporal coverage of high-energy gamma-ray turned out to be longer than that of the optical band. The behavior should be longer than the light curve duration.
The results of the QPO analysis were consistent with the periodic detection in the G-band light curve. According to the authors of the paper, the optical emission is similar to the gamma-ray emission.
The team is trying to find a way to explain the observed quasi-periodic behavior in PKS 0405-385.
The QPO-like ux modulations might be related to a geometrical scenario with the relativistic motion of the enhanced emission.
More information: Yunlu Gong et al, Quasi-periodic behaviour in the γ-ray light curve of the blazar PKS 0405-385. arXiv:2205.02402v1 [astro-ph.HE], arxiv.org/abs/2205.02402The Science X Network will be launched in 2022.
Citation: Quasi-periodic oscillation detected in blazar PKS 0405-385 (2022, May 16) retrieved 16 May 2022 from https://phys.org/news/2022-05-quasi-periodic-oscillation-blazar-pks-.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
All Rights Reserved © 2024
