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arXiv · 2303.05741

Gluon Condensation Signature in the GeV Gamma-Ray Spectra of Pulsars

Ze-Cheng Zou·Yong-Feng Huang·Cheng-Ming Li·He-Rui Zheng·Wei Zhu
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Abstract

The accumulation of gluons inside nucleons, i.e., the gluon condensation, may lead to a characteristic broken power-law gamma-ray spectrum in high-energy nucleon collisions. Here we show that the observed spectra of at least 25 sources in the second Fermi Large Area Telescope Catalog of Gamma-ray Pulsars can be well fitted by such a broken power-law function that has only four free parameters. It strongly indicates that the gamma-ray emission from these pulsars is of hadronic origin, but with gluon condensation inside hadrons. It is well known that the quark-gluon distribution in a free nucleon is different from that in a bound nucleon. This work exposes the nuclear $A$ dependence of the gluon condensation effect, where $A$ refers to the baryon number. Our study reveals the gluon condensation under the condition of $A\to\infty$, which may open a new window for eavesdropping on the structure of compact stars on the subnuclear level.

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Ze-Cheng Zou, Yong-Feng Huang, Cheng-Ming Li, He-Rui Zheng, Wei Zhu. 2023-03-10. Gluon Condensation Signature in the GeV Gamma-Ray Spectra of Pulsars. https://doi.org/10.1103/physrevd.107.063032

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