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تسجيل مستخدم جديدRe-examining the Solar Axion Explanation for the XENON1T Excess
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The XENON1T collaboration has observed an excess in electronic recoil events below $5~mathrm{keV}$ over the known background, which could originate from beyond-the-Standard-Model physics. The solar axion is a well-motivated model that has been proposed to explain the excess, though it has tension with astrophysical observations. The axions traveled from the Sun can be absorbed by the electrons in the xenon atoms via the axion-electron coupling. Meanwhile, they can also scatter with the atoms through the inverse Primakoff process via the axion-photon coupling, which emits a photon and mimics the electronic recoil signals. We found that the latter process cannot be neglected. After including the $rm{keV}$ photon produced via inverse Primakoff in the detection, the tension with the astrophysical constraints can be significantly reduced. We also explore scenarios involving additional new physics to further alleviate the tension with the astrophysical bounds.
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We argue that the interpretation in terms of solar axions of the recent XENON1T excess is not tenable when confronted with astrophysical observations of stellar evolution. We discuss the reasons why the emission of a flux of solar axions sufficiently
intense to explain the anomalous data would radically alter the distribution of certain type of stars in the color-magnitude diagram in first place, and would also clash with a certain number of other astrophysical observables. Quantitatively, the significance of the discrepancy ranges from $3.3sigma$ for the rate of period change of pulsating White Dwarfs, and exceedes $19sigma$ for the $R$-parameter and for $M_{I,{rm TRGB}}$.
This work is a study of some possible background sources in the XENON1T environment which might affect the energy spectrum of electronic recoil events in the lower side and might contribute to the observed excess. We have identified some additional p
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Solar interpretations of the recent XENON1T excess events, such as axion or dark photon emissions from the sun, are thought to be at odds with stellar cooling bounds from the horizontal branch stars and red giants. We propose a simple effective field
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, the axion gets its mass via radiative corrections at one-loop level mediated by virtual top quark, right handed Majorana neutrinos and SM gauge bosons. Its mass is obtained in the range $4$ keV$div$ $40$ keV, consistent with the one predicted by XENON1T experiment, when the right handed Majorana neutrino mass is varied from $100$ GeV up to $350$ GeV, thus implying that the light active neutrino masses are generated from a low scale type I seesaw mechanism. Furthermore, the theory under consideration can also successfully accommodates the XENON1T excess provided that the PQ symmetry is spontaneously broken at the $10^{10}$ GeV scale.
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