TY - JOUR
T1 - High-energy neutrinos from multibody decaying dark matter
AU - Hiroshima, Nagisa
AU - Kitano, Ryuichiro
AU - Kohri, Kazunori
AU - Murase, Kohta
N1 - Funding Information:
This work is partially supported by Japanese Society for the Promotion of Science (JSPS) KAKENHI Grants No. 15H03669 and No. 15KK0176 (R. K.), No. 26247042 and No. JP1701131 (K. K.), and Ministry of Educations, Culture, Sports, Science and Technology-Japan (MEXT) KAKENHI Grants No. 25105011 (R. K.), No. JP15H05889 and No. JP16H0877 (K. K.). The work of K. M. is supported by NSF Grant No. PHY-1620777.
Publisher Copyright:
© 2018 authors. Published by the American Physical Society.
PY - 2018/1/10
Y1 - 2018/1/10
N2 - Since the report of the PeV-TeV neutrinos by the IceCube Collaboration, various particle physics models have been proposed to explain the neutrino spectrum by dark matter particles decaying into neutrinos and other standard model particles. In such scenarios, simultaneous γ-ray emission is commonly expected. Therefore, multimessenger connections are generally important for the indirect searches of dark matters. The recent development of γ-ray astronomy puts stringent constraints on the properties of dark matter, especially by observations with the Fermi γ-ray satellite in the last several years. Motivated by the lack of γ-ray as well as the shape of the neutrino spectrum observed by IceCube, we discuss a scenario in which the DM is a PeV scale particle which couples strongly to other invisible particles and its decay products do not contain a charged particle. As an example to realize such possibilities, we consider a model of fermionic dark matter that decays into a neutrino and many invisible fermions. The dark matter decay is secluded in the sense that the emitted products are mostly neutrinos and dark fermions. One remarkable feature of this model is the resulting broadband neutrino spectra around the energy scale of the dark matter. We apply this model to multi-PeV dark matter, and discuss possible observable consequences in light of the IceCube data. In particular, this model could account for the large flux at medium energies of ∼10-100 TeV, possibly as well as the second peak at PeV, without violating the stringent γ-ray constraints from Fermi and air-shower experiments such as CASA-MIA.
AB - Since the report of the PeV-TeV neutrinos by the IceCube Collaboration, various particle physics models have been proposed to explain the neutrino spectrum by dark matter particles decaying into neutrinos and other standard model particles. In such scenarios, simultaneous γ-ray emission is commonly expected. Therefore, multimessenger connections are generally important for the indirect searches of dark matters. The recent development of γ-ray astronomy puts stringent constraints on the properties of dark matter, especially by observations with the Fermi γ-ray satellite in the last several years. Motivated by the lack of γ-ray as well as the shape of the neutrino spectrum observed by IceCube, we discuss a scenario in which the DM is a PeV scale particle which couples strongly to other invisible particles and its decay products do not contain a charged particle. As an example to realize such possibilities, we consider a model of fermionic dark matter that decays into a neutrino and many invisible fermions. The dark matter decay is secluded in the sense that the emitted products are mostly neutrinos and dark fermions. One remarkable feature of this model is the resulting broadband neutrino spectra around the energy scale of the dark matter. We apply this model to multi-PeV dark matter, and discuss possible observable consequences in light of the IceCube data. In particular, this model could account for the large flux at medium energies of ∼10-100 TeV, possibly as well as the second peak at PeV, without violating the stringent γ-ray constraints from Fermi and air-shower experiments such as CASA-MIA.
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U2 - 10.1103/PhysRevD.97.023006
DO - 10.1103/PhysRevD.97.023006
M3 - Article
AN - SCOPUS:85042085596
SN - 2470-0010
VL - 97
JO - Physical Review D
JF - Physical Review D
IS - 2
M1 - 023006
ER -