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arXiv · 2605.26220

Strong Constraints on Millisecond Pulsar Injection Spectra from Fermi-LAT Observations of the Galactic Center

Jordan Koechler·Pedro De la Torre Luque·Mattia Di Mauro
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Abstract

Millisecond pulsars (MSPs) are a leading explanation of the Galactic Center excess (GCE) observed in Fermi-LAT data. We constrain this scenario by jointly modeling prompt and inverse-Compton $\gamma$ rays from MSP-injected $e^\pm$ on the Galactic bulge, using recent Fermi-LAT GCE spectra from state-of-the-art interstellar emission models and data analysis. Current data place strong upper limits on the efficiency ratio $\eta_e/\eta_\gamma$ across broad $e^\pm$ injection scenarios, surpassing those from globular-cluster observations with MAGIC and competitive with projected CTAO sensitivities toward the Galactic bulge.

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Jordan Koechler, Pedro De la Torre Luque, Mattia Di Mauro. 2026-05-25. Strong Constraints on Millisecond Pulsar Injection Spectra from Fermi-LAT Observations of the Galactic Center. https://arxiv.org/abs/2605.26220

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