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From the 2 of 7 linked papers with an AI index.

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7 papers

astro-ph.CO2026

Cosmological - Pair-Production Background

Mika A. Gelowicz, Thomas Siegert, Saurabh Mittal +10

The paper calculates how photons from the cosmic photon background interact with each other to produce electron‑positron pairs across cosmic time, and evaluates the resulting secon…

astro-ph.GA2026

Stellar flares cannot explain the Galactic 511 keV emission

Saurabh Mittal, Thomas Siegert, Francesca Calore +12

The authors assess whether stellar flares can produce enough positrons to explain the Milky Way’s 511 keV annihilation line and conclude that flares fall short by several orders of…

astro-ph.HE2026

On the Possibility of an Extragalactic Positron Annihilation Signal

Thomas Siegert, Hiroki Yoneda

With 20 years of INTEGRAL/SPI observations, Yoneda et al. (2025) created the most detailed map of the positron annihilation line at 511keV. While central bulge and extended disk ar…

astro-ph.HE2025

Search for Axion-Like Particles from Nearby Pre-Supernova Stars

Saurabh Mittal, Thomas Siegert, Francesca Calore +7

Axion-like particles (ALPs) are hypothetical pseudoscalar bosons that arise in many extensions of the Standard Model and are well-motivated dark matter candidates. Nearby massive s…

astro-ph.HE2025

Imaging the positron annihilation line with 20 years of INTEGRAL/SPI observations

Hiroki Yoneda, Thomas Siegert, Saurabh Mittal

The e e annihilation line at 511 keV provides a unique probe for studying the distribution and origin of positrons in our Galaxy. The SPI spectrometer on INTEGRAL has obser…

hep-ph2025

Light WIMPs and MeV Gamma-ray Detection with COSI

Yu Watanabe, Shigeki Matsumoto, Christopher M. Karwin +6

Light weakly interacting massive particles (WIMPs), whose masses are in the sub-GeV scale, have been attracting more attention due to the negative results searching for traditional…