Abstract
The observed anomalous excess of high-energy cosmic ray (CR) positrons is widely discussed as possible indirect evidence for dark matter (DM). However, any source of cosmic positrons is inevitably the source of gamma radiation. The least model dependent test of CR anomalies interpretation via DM particles decays (or annihilation) is connected with gamma-ray background due to gamma overproduction in such processes. In this work, we impose an observational constraint on gamma ray production from DM. Then, we study the possible suppression of gamma yield in the DM decays into identical final fermions. Such DM particles arise in the multi-component dark atom model. The influence of the interaction vertices on the gamma suppression was also considered. No essential gamma suppression effects are found. However, some minor ones are revealed.
Highlights
The physical nature of dark matter (DM) still is unknown and it s obviously connected with physics beyond the Standard Model (SM) Many DM search attempts, both direct in underground experiments and accelerator ones and indirect in cosmic ray (CR) experiments are undertaken
In our works [1,2,3,5,9] we have shown that the DM models explaining the positron anomaly in most cases have major problems with gamma-ray constraints, the one set by IGRB data obtained by Fermi-LAT experiment [12]
We consider the AMS-02 [11] data on the positron fraction and the basic leptophilic DM model with DM particle being able to annihilate into lepton-antilepton pairs
Summary
The physical nature of DM still is unknown and it s obviously connected with physics beyond the Standard Model (SM) Many DM search attempts, both direct in underground experiments and accelerator ones and indirect in cosmic ray (CR) experiments are undertaken. We continue our investigations in this field [1,2,3,4,5,6,7,8,9,10]. This note is devoted to the explanation of cosmic positron excess in the AMS-02 data [11] with the help of DM annihilation or decay in Galaxy. As it was shown previously, the main problem lies in the predicted contradiction with the data in gamma-ray background obtained by Fermi-LAT [12]. Many things have already been done in this field. This article considers several new mechanisms of gamma-ray suppression and estimates the necessary level of such suppression
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
