3 papers
astro-ph.HE2026
The Double-Peaked Calcium-Strong SN 2025coe: Progenitor Constraints from Early Interaction and Ejecta Asymmetries
Aravind P. Ravi, Sahana Kumar, Raphael Baer-Way +47
Supernova (SN) 2025coe at a distance of 25 Mpc is the second-closest calcium-strong (CaST) transient. It was discovered at a large projected offset of 34 kpc from its p…
astro-ph.HE2026
Spectral Variations of -rays in Mrk 421
Rui-Qi Huang, Xin-Ke Hu, Yu-Wei Yu +2
We present a comprehensive analysis of the 17-year Fermi-LAT observational data of Mrk 421 to investigate the spectral variations in the -ray bands. The light curve of the sour…
astro-ph.HE2025
SN 2021hpr: A Normal Type Ia Supernova Showing Excess Emission in the Early Rising Phase
Abdusamatjan Iskandar, Xiaofeng Wang, Ali Esamdin +37
We present extensive optical observations of a nearby Type Ia supernova (SN Ia), SN 2021hpr, located in the spiral galaxy NGC 3147 at a distance of 45 Mpc. Our observations…