832 research outputs found
Revisit of cosmic ray antiprotons from dark matter annihilation with updated constraints on the background model from AMS-02 and collider data
We study the cosmic ray antiprotons with updated constraints on the
propagation, proton injection, and solar modulation parameters based on the
newest AMS-02 data near the Earth and Voyager data in the local interstellar
space, and on the cross section of antiproton production due to proton-proton
collisions based on new collider data. We use a Bayesian approach to properly
consider the uncertainties of the model predictions of both the background and
the dark matter (DM) annihilation components of antiprotons. We find that
including an extra component of antiprotons from the annihilation of DM
particles into a pair of quarks can improve the fit to the AMS-02 antiproton
data considerably. The favored mass of DM particles is about GeV,
and the annihilation cross section is just at the level of the thermal
production of DM ( cm~s).Comment: 15 pages, 5 figures and 1 table; JCAP accepted versio
2-Fluoro-N′-(2-hyÂdroxyÂbenzylÂidene)benzohydrazide
In the title compound, C14H11FN2O2, an intraÂmolecular O—H⋯N hydrogen bond influences the molÂecular conformation; the two benzene rings form a dihedral angle of 18.4 (3)°. The F atom is disordered over two positions in a 0.717 (5):0.283 (5) ratio. In the crystal, interÂmolecular N—H⋯O hydrogen bonds link the molÂecules into chains extending along the c axis
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