arXiv subjects

Jia-Neng Zhou

Publications and source records attributed to Jia-Neng Zhou.

2 recordsLinked to original sources

arXiv2020

A gamma-ray periodic modulation in Globular Cluster 47 Tucanae

The Globular Cluster 47 Tucanae was firstly detected in gamma-rays by the Large Area Telescope (LAT) onboard the \emph{Fermi} Gamma-ray Space Telescope, and the gamma-ray emission has been widely attributed to the millisecond pulsars. In this work, we analyze the Fermi-LAT pass 8 data ranging from 2008 August to 2017 May and report the detection of a modulation with a period of $18.416\pm0.008$ hours at a significance level of $\sim 4.8σ$. This is the first time to detect a significant modulation with a period much longer than that of millisecond pulsars in gamma-rays from Globular Clusters. The periodic modulation signal appears in the {\it Swift}-BAT data as well. The phase-folded Chandra X-ray light curve of a point source may have provided an additional clue.

astro-ph.HE↗

arXiv2017

A $γ$-ray Quasi-Periodic modulation in the Blazar PKS 0301$-$243?

We report a nominally high-confidence $γ$-ray quasi-periodic modulation in the blazar PKS 0301$-$243. For this target, we analyze its \emph{Fermi}-LAT Pass 8 data covering from 2008 August to 2017 May. Two techniques, i.e., the maximum likelihood optimization and the exposure-weighted aperture photometry, are used to build the $γ$-ray light curves. Then both the Lomb-Scargle Periodogram and the Weighted Wavelet Z-transform are applied to the light curves to search for period signals. A quasi-periodicity with a period of $2.1\pm0.3$ yr appears at the significance level of $\sim5σ$, although it should be noted that this putative quasi-period variability is seen in a data set barely four times longer. We speculate that this $γ$-ray quasi-periodic modulation might be evidence of a binary supermassive black hole.

astro-ph.HE↗