Results 91 to 100 of about 479,061 (218)
Lessons from the apparent peculiar nature of the star TYC 6544‐3483‐1
Astronomische Nachrichten, Volume 345, Issue 4, May 2024.Abstract We report a radio and optical study of the star TYC 6544‐3483‐1 originally selected as a follow‐up target in the course of our efforts to cross‐identify Galactic high‐energy sources. The star by itself finally turned out to be a very ordinary main‐sequence star despite the initial expectations that apparently pointed to the contrary.
Josep Martí +5 more
wiley +1 more source
Asymptotically‐Flat Black Hole Solutions in Symmergent Gravity
Fortschritte der Physik, Volume 72, Issue 4, April 2024.Abstract Symmergent gravity is an emergent gravity model with an R+R2$R+R^2$ curvature sector and an extended particle sector having new particles beyond the known ones. With constant scalar curvature, asymptotically flat black hole solutions are known to have no sensitivity to the quadratic curvature term (coefficient of R2$R^2$). With variable scalar
Beyhan Puliçe +3 more
wiley +1 more source
Unveiling the Origin of the Fermi Bubbles
Galaxies, 2018 The Fermi bubbles, two giant structures above and below the Galactic center (GC), are among the most important discoveries of the Fermi Gamma-ray Space Telescope.
H.-Y. Karen Yang +2 more
doaj +1 more source
On the Spectral Shape of Non-recycled γ-ray Pulsars [PDF]
Journal of Astronomy and Space Sciences, 2016 More than 100 γ−ray pulsars have been discovered by the Fermi Gamma-ray Space Telescope. With a significantly enlarged sample size, it is possible to compare the properties of different classes. Radio-quiet (RQ) γ−ray pulsars form a distinct population,
Chung-Yue Hui, Jongsu Lee
doaj +1 more source
Cosmology with Gravitational Waves: A Review
Annalen der Physik, Volume 536, Issue 2, February 2024.The review gives an overview of the most recent advances in gravitational‐wave (GWs) cosmology. After an in‐depth discussion of methodologies and tools for GW cosmology, it presents the latest results on measurements of standard cosmological parameters from the LIGO, Virgo, and KAGRA detections.
Simone Mastrogiovanni +6 more
wiley +1 more source
Universe, 2022 The blazar PKS 0208-512 was in the lowest γ-ray brightness state during the initial 10 years of observations with the Fermi Gamma-ray Space Telescope (Fermi), which was an order of magnitude lower than its flux state during the EGRET era (1991–2000). The
Krishna Mohana Ammenadka +4 more
doaj +1 more source
, 2009 An overview of the Fermi Gamma-ray Space Telescope's first 6 months in operation is provided. The Fermi Gamma-ray Space Telescope, formerly called GLAST, is a mission to measure the cosmic gamma-ray flux in the energy rage 20 MeV to more than 300 GeV ...
Hays, Elizabeth
core +1 more source
Nuclear astrophysicists at war
Natural Sciences, Volume 4, Issue 1, January 2024.The Manhattan program not only opened the path to the nuclear age for humans, but also triggered a lot of new questions and research directions in nuclear physics and astrophysics that still inform the ideas in these fields today. Abstract The question of energy production in stars stimulated an entire generation of young physicists in the 1930s who ...
Michael Wiescher, Karlheinz Langanke
wiley +1 more source
Probing photon-ALP oscillations from the flat spectrum radio quasar 4C+21.35
Physics Letters B, 2022 Flat spectrum radio quasar (FSRQ) is the most luminous blazar at the GeV energies. In this paper, we probe the photon-axion-like particle (ALP) oscillation effect on the latest very-high-energy (VHE) γ-ray observations of the FSRQ 4C+21.35 (PKS 1222+216).
Hai-Jun Li
doaj
Searching for γ-ray Emission from Binary Black-Hole Mergers Detected in LIGO/Virgo O3 Run
Universe, 2022 We conduct searches for γ-ray emission from the binary black-hole (BBH) mergers reported in the Gravitational-Wave Candidate Event Database (GraceDB). The γ-ray data are from the all-sky survey of the Large-Area Telescope (LAT) onboard the Fermi Gamma ...
Chongyang Ren, Zhongxiang Wang
doaj +1 more source