Zobrazeno 1 - 10
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pro vyhledávání: '"Li, Shao-Ping"'
Autor:
Li, Shao-Ping
Even after dark matter chemically freezes out in the early universe, electromagnetic cascades from dark matter annihilation can still perturb the background photon spectrum when the universe temperature cools down to 0.5 keV. We revisit the CMB spect
Externí odkaz:
http://arxiv.org/abs/2402.16708
Autor:
Li, Shao-Ping, Yu, Bingrong
A singlet majoron can arise from the seesaw framework as a pseudo-Goldstone boson when the heavy Majorana neutrinos acquire masses via the spontaneous breaking of global ${\rm U}(1)_L$ symmetry. The resulting cosmological impacts are usually derived
Externí odkaz:
http://arxiv.org/abs/2310.13492
Autor:
Kanemura, Shinya, Li, Shao-Ping
A dark sector is an interesting place where a strong first-order phase transition, observable gravitational waves and/or a dark matter candidate could arise. However, the experimental tests for such a dark sector could be ambiguous due to the dark co
Externí odkaz:
http://arxiv.org/abs/2308.16390
Autor:
Li, Shao-Ping, Xu, Xun-Jie
We investigate the impact of new light particles, carrying significant energy in the early universe after neutrino decoupling, on the cosmological effective relativistic neutrino species, $N_{{\rm eff}}$. If the light particles are produced from deco
Externí odkaz:
http://arxiv.org/abs/2307.13967
Autor:
Li, Shao-Ping, Xie, Ke-Pan
A cosmic first-order phase transition (FOPT) occurring at MeV-scale provides an attractive explanation for the nano-Hertz gravitational wave (GW) background indicated by the recent pulsar timing array data from the NANOGrav, CPTA, EPTA and PPTA colla
Externí odkaz:
http://arxiv.org/abs/2307.01086
Autor:
Li, Shao-Ping, Xu, Xun-Jie
Light weakly interacting particles could be copiously produced in the Sun which, as a well-understood star, could provide severe constraints on such new physics. In this work, we calculate the solar production rates of light gauge bosons (e.g. dark p
Externí odkaz:
http://arxiv.org/abs/2304.12907
Autor:
Li, Shao-Ping
The connection between a hidden nonthermal sector and a thermal plasma can be established by a light thermal fermion mediator. When the fermion mediator is much lighter than the hidden species, kinematically forbidden decay of the mediator can be ope
Externí odkaz:
http://arxiv.org/abs/2301.02835
Autor:
Li, Shao-Ping, Xu, Xun-Jie
Right-handed neutrinos (RHNs) provide a natural portal to a dark sector accommodating dark matter (DM). In this work, we consider that the dark sector is connected to the standard model only via RHNs and ask how DM can be produced from RHNs. Our fram
Externí odkaz:
http://arxiv.org/abs/2212.09109
Autor:
Li, Shao-Ping
It is generically believed that the two-body scattering is suppressed by higher-order weak couplings with respect to the two-body decay. We show that this does not always hold when a heavy particle is produced by forbidden decay in a thermal plasma,
Externí odkaz:
http://arxiv.org/abs/2211.16802
Autor:
Li, Shao-Ping, Xu, Xun-Jie
In the early universe, Dirac neutrino magnetic moments due to their chirality-flipping nature could lead to thermal production of right-handed neutrinos, which would make a significant contribution to the effective neutrino number, $N_{\rm eff}$. We
Externí odkaz:
http://arxiv.org/abs/2211.04669