16 papers
Constraints on the VHE counterpart of two binary black hole mergers observed by the MAGIC and CTAO LST-1 telescopes
K. Abe, S. Abe, J. Abhir +439
We present very-high-energy gamma-ray observations of two binary black hole merger candidates, GW240615_113620 and GW241125_010116, performed with the Major Atmospheric Gamma Imagi…
Extreme Blazars Observed with MAGIC: Second Catalog Release
K. Abe, S. Abe, J. Abhir +353
Extremely high-peaked BL Lac objects - also named extreme blazars - are among the most energetic and persistent extragalactic accelerators in the Universe, defined by a synchrotron…
Design of a mission to measure the shape and substructure of the 511 keV gamma-ray line from the center of the Milky Way
Kun Hu, Matthew Fritts, Daniel Becker +23
The 511 keV electron-positron annihilation feature near the galactic center has been detected for more than half a century, yet its origin remains a mystery. In this paper, we desc…
Refined Constraints on the Hard X-ray Polarization of the Crab Pulsar and Nebula Derived from an Extended XL-Calibur Dataset
Matthew G. Baring, Jacob Casey, Sohee Chun +26
We present updated hard X-ray polarization measurements of the Crab pulsar and nebula obtained with the balloon-borne polarimeter XL-Calibur in the ~19-64 keV energy range. During…
A New Approach for Testing Einstein's Theory of Gravity Close to Rapidly Spinning Black Holes
Shravan Vengalil Menon, Kun Hu, Henric Krawczynski
The Penrose process and the collisional Penrose process involve particles decaying or interacting very close to a spinning black hole, respectively, during which some particles are…
GRB 221009A: Observations with LST-1 of CTAO and Implications for Structured Jets in Long Gamma-Ray Bursts
LST Collaboration, K. Abe, S. Abe +328
GRB 221009A is the brightest gamma-ray burst (GRB) observed to date. Extensive observations of its afterglow emission across the electromagnetic spectrum were performed, providing…