7–11 Dec 2026
The University of Sydney
Australia/Sydney timezone
AIP Congress 2026

Stellar Halos as Probes of Interstellar Cosmic-Ray Electrons with Fermi--LAT

Not scheduled
1h 30m
Belinda Hutchinson Building (The University of Sydney )

Belinda Hutchinson Building

The University of Sydney

Abercrombie St & Codrington St NSW 2008
Invited talk AIP | Astroparticle Physics (GAP) Parallel sessions

Speaker

Peter Marinos (Stanford University)

Description

High-precision measurements of cosmic-ray (CR) electrons are confined to the heliospheric environment, leaving the distribution in the nearby interstellar medium poorly constrained. We propose to probe the CR-electron spectrum outside the heliosphere by searching for extended Compton emissions from the stellar radiation fields surrounding individual stars in Fermi--LAT data. We have identified a sample of isolated O- and B-type stars at high Galactic latitudes where the predicted Compton emission is comparable to the diffuse background, reducing the source confusion that limited previous studies. We also create custom models of the diffuse background from dust maps computed from Gaia stellar-extinction data, allowing us to separate structures along the line of sight at parsec-scale resolutions. Detection of these Compton gamma-ray halos would enable the first direct constraints on the CR electron intensity at distances of 100--400 pc from the Solar system. Here we will report on our preliminary results.

I am the presenting author Yes

Author

Peter Marinos (Stanford University)

Co-authors

Igor Moskalenko Troy Porter (Stanford University)

Presentation materials

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