238 citations · 1.4k across the 44 of their papers we have counts for
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A merger within a merger: Chandra pinpoints the short GRB 230906A in a peculiar environment
S. Dichiara, E. Troja, B. O'Connor +6
We report the precise X-ray localization of GRB 230906A, a short duration (0.9 s) burst with no optical or radio counterpart. Deep imaging with the Hubble Space Telesco…
Analysis of GRB Closure Relationship in Multi-wavelengths
M. G. Dainotti, S. Bhardwaj, E. Bissaldi +3
Gamma-ray bursts (GRBs) are intense pulses of high-energy emission associated with massive stars' death or compact objects' coalescence. Their multi-wavelength observations help ve…
Synchrotron self-Compton in a radiative-adiabatic fireball scenario: Modelling the multiwavelength observations in some Fermi/LAT bursts
Nissim Fraija, P. Veres, B. Betancourt Kamenetskaia +4
Energetic GeV photons expected from the closest and the most energetic Gamma-ray bursts (GRBs) provide an unique opportunity to study the very-high-energy emission as well as the p…
An Explanation of GRB Fermi-LAT Flares and High-Energy Photons in Stratified Afterglows
Nissim Fraija, Boris Betancourt Kamenetskaia, Antonio Galván-Gámez +6
The second {\itshape Fermi}/LAT gamma-ray burst (GRB) catalog (2FLGC) spanning the first decade of operations by the LAT collaboration was recently released. The closure relations…
Off-axis Afterglow Closure Relations and Fermi-LAT Detected Gamma-Ray Bursts
Nissim Fraija, M. G. Dainotti, D. Levine +2
Gamma-ray bursts (GRBs) are one of the most promising transient events for studying multi-wavelength observations in extreme conditions. Observation of GeV photons from bursts woul…
Closure Relations of Synchrotron Self-Compton in Afterglow stratified medium and Fermi-LAT Detected Gamma-Ray Bursts
Nissim Fraija, Maria G. Dainotti, B. Betancourt Kamenetskaia +2
The Second Gamma-ray Burst Catalog (2FLGC) was announced by the Fermi Large Area Telescope (Fermi-LAT) Collaboration. It includes 29 bursts with photon energy higher than 10 GeV. G…
Evidence of a lepto-hadronic two-zone emission in flare states
E. Aguilar-Ruiz, N. Fraija, A. Galván-G ámez
The BL Lac Markarian 501 exhibited two flaring activities in the very-high-energy (VHE) band in May 2009. The lack of correlation between X-rays and TeV gamma-rays without increasi…
High-Energy Neutrino Fluxes from Hard-TeV BL Lacs
E. Aguilar-Ruiz, N. Fraija, A. Galván-Gámez
Blazars have been pointed out as promising high-energy (HE) neutrinos sources, although the mechanism is still under debate. The blazars with a hard-TeV spectrum, which leptonic mo…
Polarization From A Radially Stratified Off-Axis GRB Outflow
A. C. Caligula do E. S. Pedreira, N. Fraija, A. Galvan-Gamez +5
While the dominant radiation mechanism gamma-ray bursts (GRBs) remains a question of debate, synchrotron emission is one of the foremost candidates to describe the multi-wavelength…
Afterglow Polarization from Off-Axis GRB Jets
A. C. Caligula do E. S. Pedreira, N. Fraija, A. Galvan-Gamez +5
As we further our studies on Gamma-ray bursts (GRBs), both on theoretical models and observational tools, more and more options begin to open for exploration of its physical proper…
Exploring the Early Afterglow Polarization of GRB 190829A
A. C. Caligula do E. S. Pedreira, N. Fraija, S. Dichiara +5
The GRB 190829A has been widely studied due to its nature and the high energy emission presented. Due to the detection of a very-high-energy component by the High Energy Stereoscop…
GRB Afterglow of the Sub-relativistic Materials with Energy Injection
N. Fraija, B. Betancourt Kamenetskaia, A. Galvan-Gamez +5
Sub-relativistic materials launched during the merger of binary compact objects and the core-collapse of massive stars acquire velocity structures when expanding in a stratified en…
A Two-Zone Model as origin of Hard TeV Spectrum in Extreme BL Lacs
E. Aguilar-Ruiz, N. Fraija, A. Galvan-Gamez +1
The emission of the so-called extreme BL Lacs poses challenges to the particle acceleration models. The hardness of their spectrum, , in the high-energy band demands un…
A theoretical model of an off-axis GRB jet
B. Betancourt Kamenetskaia, N. Fraija, M. Dainotti +3
In light of the most recent observations of late afterglows produced by the merger of compact objects or by the core-collapse of massive dying stars, we research the evolution of t…
HAWC observations of the acceleration of very-high-energy cosmic rays in the Cygnus Cocoon
A. U. Abeysekara, A. Albert, R. Alfaro +98
Cosmic rays with energies up to a few PeV are known to be accelerated within the Milky Way. Traditionally, it has been presumed that supernova remnants were the main source of very…
HAWC Search for High-Mass Microquasars
HAWC Collaboration, A. Albert, R. Alfaro +87
Microquasars with high-mass companion stars are promising very-high-energy (VHE; 0.1-100 TeV) gamma-ray emitters, but their behaviors above 10 TeV are poorly known. Using the High…
Probing the Sea of Cosmic Rays by Measuring Gamma-Ray Emission from Passive Giant Molecular Clouds with HAWC
A. Albert, R. Alfaro, C. Alvarez +87
The study of high-energy gamma rays from passive Giant Molecular Clouds (GMCs) in our Galaxy is an indirect way to characterize and probe the paradigm of the "sea" of cosmic rays i…
Evidence of 200 TeV photons from HAWC J1825-134
A. Albert, R. Alfaro, C. Alvarez +81
The Earth is bombarded by ultra-relativistic particles, known as cosmic rays (CRs). CRs with energies up to a few PeV (=10 eV), the knee in the particle spectrum, are believ…
Cosmic rays, neutrinos and GeV-TeV gamma rays from Starburst Galaxy NGC 4945
E. Aguilar-Ruiz, N. Fraija, Jagdish C. Joshi +2
The detection of high-energy astrophysical neutrinos and ultra-high-energy cosmic rays (UHECRs) provides a new way to explore sources of cosmic rays. One of the highest energy neut…
HAWC and Fermi-LAT Detection of Extended Emission from the Unidentified Source 2HWC J2006+341
A. Albert, R. Alfaro, C. Alvarez +71
The discovery of the TeV point source 2HWC J2006+341 was reported in the second HAWC gamma-ray catalog. We present a follow-up study of this source here. The TeV emission is best d…
A survey of active galaxies at TeV photon energies with the HAWC gamma-ray observatory
A. Albert, C. Alvarez, J. R. Angeles Camacho +86
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 exposu…
3HWC: The Third HAWC Catalog of Very-High-Energy Gamma-ray Sources
A. Albert, R. Alfaro, C. Alvarez +104
We present a new catalog of TeV gamma-ray sources using 1523 days of data from the High Altitude Water Cherenkov (HAWC) observatory. The catalog represents the most sensitive surve…
HAWC J2227+610 and its association with G106.3+2.7, a new potential Galactic PeVatron
A. Albert, R. Alfaro, C. Alvarez +97
We present the detection of VHE gamma-ray emission above 100 TeV from HAWC J2227+610 with the HAWC observatory. Combining our observations with previously published results by VERI…
On the origin of the multi-GeV photons from the closest burst with intermediate luminosity: GRB 190829A
N. Fraija, P. Veres, P. Beniamini +4
Very-high-energy (VHE) emission is usually interpreted in the synchrotron-self Compton (SSC) scenario, and expected from the low-redshift and high-luminosity gamma-ray bursts (GRBs…