We study the cosine similarity of sentence transformer embeddings and observe that they are well modeled by gamma mixtures. From a fixed corpus, we measure similarities between all document embeddings and a reference query embedding. Empirically we f...
We will report the observations of TeV gamma ray flares from Markarian 501 using Telescope Array Prototype. The observation were carried out continuously from the end of March to the end of July in 1997. The energy spectrum, and the time variation...
It is difficult to discover pulsars via their gamma-ray emission because current instruments typically detect fewer than one photon per million rotations. This creates a significant computing challenge for isolated pulsars, where the typical paramete...
In the paper, necessary and sufficient conditions are presented for a function involving a ratio of gamma functions to be logarithmically completely monotonic. This extends and generalizes the main result in [\emph{Inequalities and monotonicity for t...
Central engine of gamma-ray bursts (GRBs) may be intermittent and launch several episodes of ejecta separated by a long quiescent interval. In this scenario, an external shock is formed due to the propagation of the first launched ejecta into the cir...
The number of strong (equivalent width > 1A) MgII absorbers observed towards Gamma-ray bursts (GRBs) has been found to be statistically larger than the number of strong absorbers towards quasi-stellar objects (QSOs). We formalize this "MgII problem"...
We discuss the origin of continuum and line X-ray emission observed in the direction the Galactic Center. We predict a significant flux of de-excitation gamma-ray lines in this direction, which can be produced by subrelativistic protons generated b...
The production of high invariant mass opposite sign lepton pairs in proton-proton collisions at the LHC is dominated by the Drell-Yan process. In addition to this photon or Z exchange mediated mechanism, gamma-gamma collisions, where photons radiated...
Decades of improving data and extensive theoretical research have led to a popular model of gamma-ray bursts. According to this model, a catastrophic event in a stellar system results in the formation of a compact central engine, which releases a fra...
Exceptional observational breakthroughs in the field of Gamma Ray Burst research are not paralleled by theoretical advances. In this review, based on the introductory talk given at the "The Shocking Universe" meeting, I argue that any present day m...
The spectrometer SPI, one of the two main instruments of the INTEGRAL spacecraft, has strong capabilities in the Field of Gamma-Ray Burst (GRB) detections. In its 16 degree Field of view (FoV) SPI is able to trigger and to localize GRBs. With its l...
For over 25 years, the origin of long-duration gamma-ray bursts (lGRBs) has been linked to the collapse of rotating massive stars. However, we have yet to pinpoint the stellar progenitor powering these transients. Moreover, the dominant engine poweri...
We report on the gamma-ray activity of the high-synchrotron-peaked BL Lacertae object Mrk 421 during the first 1.5 years of Fermi operation, from 2008 August 5 to 2010 March 12. We find that the Large Area Telescope (LAT) gamma-ray spectrum above 0.3...
We study q-integral representations of the q-gamma and the q-beta functions. This study leads to a very interesting q-constant. As an application of these integral representations, we obtain a simple conceptual proof of a family of identities for J...
We have calculated the next-to-leading order cross section for the inclusive production of charm quarks as a function of the transverse momentum p_T and the rapidity in two approaches using massive or massless charm quarks. For the single-resolved...
The VERITAS gamma-ray observatory has an active multimessenger program, currently focused on studying the connection between very-high-energy gamma rays and the astrophysical neutrino flux recently discovered by the IceCube telescope. As both gammara...
The recent observation of the gamma ray burster GRB 990123, requiring at least two solar masses of energy in gamma radiation alone, created an energy crisis in astrophysics (Schilling 1999). We discuss a theorem which states that, of all four-dimen...
We investigate the high energy emission activities of two bright gamma-ray pulsars, PSR~J2021+4026 and Vela. For PSR~J2021+4026, the state changes in the gamma-ray flux and spin-down rate have been observed. We report that the long-term evolution of...
We present the light curve data of a remarkable blazer 3C 454.3 (z=0.859) in optical, X-ray, and gamma-ray bands. Since January 2008, we have been monitoring this object using the 50 cm MITSuME, a optical telescope, and detected several flares includ...
The WIDeField telescope for Gamma-ray burst Early Timing (WIDGET) is used for a fully automated, ultra-wide-field survey aimed at detecting the prompt optical emission associated with Gamma-ray Bursts (GRBs). WIDGET surveys the HETE-2 and Swift/BAT p...