Yu-Liang Xin

DISCOVERY OF gamma-RAY EMISSION FROM THE STRONGLY LOBE-DOMINATED QUASAR 3C 275.1

We systematically analyze the 6 year Fermi/Large Area Telescope (LAT) data on lobe-dominated quasars (LDQs) in the complete LDQ sample from the Revised third Cambridge Catalogue of Radio Sources (3CRR) survey and report the discovery of high-energy gamma-ray emission from 3C 275.1. The gamma-ray emission of 3C 207 is confirmed and significant variability of the light curve is identified. We do not find statistically significant gamma-ray emission from other LDQs. 3C 275.1 is the known gamma-ray quasar with the lowest core dominance parameter (i.e., R=0.11). We also show that both the northern radio hotspot and parsec jet models can reasonably reproduce the gamma-ray data. The parsec jet model, however, is favored by the potential gamma-ray variability on a timescale of months. We suggest that some dimmer gamma-ray LDQs will be detected in the future and LDQs could contribute non-ignorably to the extragalactic gamma-ray background.

A GeV source in the direction of Supernova Remnant CTB 37B

Supernova remnants (SNRs) are the most attractive candidates for the acceleration sites of Galactic cosmic rays. We report the detection of GeV

EVOLUTION OF HIGH-ENERGY PARTICLE DISTRIBUTION IN MATURE SHELL-TYPE SUPERNOVA REMNANTS

\gamma

Discovery of

-ray emission with the Pass 8 events recorded by Fermi Large Area Telescope (Fermi-LAT) in the vicinity of the shell type SNR CTB 37B that is likely associated with the TeV

\gamma

\gamma-

-ray emission from the radio-intermediate quasar III Zw 2: violent jet activity with intraday

ray source HESS J1713-381. The photon spectrum of CTB 37B is consistent with a power-law with an index of

\gamma

1.89\pm0.08

-ray variability

in the energy range of

Detection of GeV Gamma-Ray Emission in the Direction of HESS J1731-347 with Fermi-LAT

0.5-500

HESS J1427−608: AN UNUSUAL HARD, UNBROKEN γ-RAY SPECTRUM IN A VERY WIDE ENERGY RANGE

GeV, and the measured flux connects smoothly with that of HESS J1713-381 at a few hundred GeV. No significant spatial extension and time variation are detected. The multi-wavelength data can be well fitted with either a leptonic model or a hadronic one. However, parameters of both models suggest more efficient particle acceleration than typical SNRs. Meanwhile, the X-ray and