Related papers: Millisecond Pulsars, TeV Halos, and Implications F…
The HAWC Gamma-Ray Observatory has reported the discovery of TeV gamma-ray emission extending several degrees around the positions of Geminga and B0656+14 pulsars. Assuming these gamma rays are produced by inverse Compton scattering off…
Enabled by the Fermi Large Area Telescope, we now know young and recycled pulsars fill the gamma-ray sky, and we are beginning to understand their emission mechanism and their distribution throughout the Galaxy. However, key questions…
Globular clusters (GCs) with their ages of the order of several billion years contain many final products of evolution of stars such as: neutron stars, white dwarfs and probably also black holes. These compact objects can be at present…
The Galactic Center Excess (GCE) $\gamma$-ray emission detected with the Large Area Telescope onboard the {\it Fermi Gamma-ray Space Telescope} has been considered as a possible sign for dark matter (DM) annihilation, but other…
The Fermi Large Area Telescope (Fermi-LAT) has recently revealed a large population of gamma-ray emitting millisecond pulsars (MSPs) in our Galaxy. We aim to infer the properties of the Galactic population of gamma-ray emitting MSPs from…
The Geminga pulsar has long been one of the most intriguing MeV-GeV gamma-ray point sources. We examine the implications of the recent Milagro detection of extended, multi-TeV gamma-ray emission from Geminga, finding that this reveals the…
The High-Altitude Water Cherenkov Telescope (HAWC) has detected TeV halos associated with two nearby pulsars/pulsar wind nebulae (PWN) -- Geminga and B0656+14. These TeV halos extend up to tens of pc from the central accelerators,…
Millisecond pulsars (MSPs) are prolific GeV $\gamma\text{-ray}$ emitters, and nearly 80\% of Fermi-LAT MSPs reside in compact binaries. We demonstrate that the companions in these compact MSPs binaries are also 511 keV annihilation line…
Studies of Fermi data indicate an excess of GeV gamma rays around the Galactic center (GC), possibly due to dark matter. We show that young gamma-ray pulsars can yield a similar signal. First, a high concentration of GC supernovae naturally…
Globular clusters are source of gamma-ray radiation. At GeV energies, their emission is attributed to magnetospheric activity of millisecond pulsars residing in the clusters. Inverse Compton scattering of ambient photon fields on…
We study the gamma-ray spectra of 30 globular clusters (GCs) thus far detected with the Fermi Gamma-ray Space Telescope. Presuming that gamma-ray emission of a GC comes from millisecond pulsars (MSPs) contained in, a model that generates…
Extended $\gamma$-ray emission has been observed around several nearby pulsars and is commonly interpreted as inverse-Compton radiation produced by relativistic electrons and positrons diffusing in the surrounding interstellar medium. In…
Millisecond pulsars (MSPs) represent nearly half of the more than 160 currently known $\gamma$-ray pulsars detected by the Large Area Telescope on the \textit{Fermi} satellite, and a third of all known MSPs are seen in $\gamma$ rays. The…
Extended regions of very high energy $\gamma$-ray emission associated with middle-aged pulsars have been found by $\gamma$-ray observatories. These regions, called TeV halos or pulsar halos, are thought to be created when energetic…
It was found in the Fermi-LAT data that there is an extended $\gamma$-ray excess in the Galactic center region. The proposed sources to be responsible for the excess include the dark matter annihilation or an astrophysical alternative from…
Many of the recently discovered TeV gamma-ray sources are associated with pulsar wind nebulae (PWNe). In fact, they represent the most populous class of Galactic sources at TeV energies. In addition, HESS has also discovered, in a survey of…
The High Altitude Water Cherenkov Gamma-Ray Observatory (HAWC) continuously detects TeV photons and particles within its large field-of-view, accumulating every day a deeper exposure of two thirds of the sky. We analyzed 1523~days of HAWC…
Using the HEGRA system of imaging atmospheric Cherenkov telescopes, one quarter of the Galactic plane (-2 deg < l < 85 deg) was surveyed for TeV gamma-ray emission from point sources and moderately extended sources (diameter <= 0.8 deg).…
TeV halos are regions of enhanced photon emissivity surrounding pulsars. While multiple sources have been discovered, a self-consistent explanation of their radial profile and spherically-symmetric morphology remains elusive due to the…
Diffuse gamma-ray emission (DGE) has been discovered over the Galactic disk in the energy range from sub-GeV to sub-PeV. While it is believed to be dominated by the pionic emission of cosmic ray (CR) hadrons via interactions with…