scholarly journals Mixed hidden sector-visible sector dark matter and observation of a CP odd Higgs boson at HL-LHC and HE-LHC

2019 ◽  
Vol 100 (1) ◽  
Author(s):  
Amin Aboubrahim ◽  
Pran Nath
2008 ◽  
Vol 23 (30) ◽  
pp. 4817-4827 ◽  
Author(s):  
O. BERTOLAMI ◽  
R. ROSENFELD

We examine a scenario where the Higgs boson is coupled to an additional Standard Model singlet scalar field from a hidden sector. We show that, in the case where this field is very light and has already relaxed to its nonzero vacuum expectation value, one gets a very stringent limit on the mixing angle between the hidden sector scalar and the Higgs field from fifth force experiments. However, this limit does not imply in a small coupling due to the large difference of vacuum expectation values. In the case that the hidden sector scalar is identified with the quintessence field, responsible for the recent acceleration of the universe, the most natural potential describing the interaction is disfavored since it results in a time-variation of the Fermi scale. We show that an ad hoc modification of the potential describing the Higgs interaction with the quintessence field may result in an unified picture of dark matter and dark energy, where dark energy is the zero-mode classical field rolling the usual quintessence potential and the dark matter candidate is the quantum excitation (particle) of the field, which is produced in the universe due to its coupling to the Higgs boson. This coupling also generates a mass for the new particle that, contrary to usual quintessence models, does not have to be small, since it does not affect the evolution of classical field. In this scenario, a feasible dark matter density can be, under conditions, obtained.


2022 ◽  
Vol 2022 (01) ◽  
pp. 005
Author(s):  
Mayumi Aoki ◽  
Jisuke Kubo ◽  
Jinbo Yang

Abstract Dynamical chiral symmetry breaking in a QCD-like hidden sector is used to generate the Planck mass and the electroweak scale including the heavy right-handed neutrino mass. A real scalar field transmits the energy scale of the hidden sector to the visible sectors, playing besides a role of inflaton in the early Universe while realizing a Higgs-inflation-like model. Our dark matter candidates are hidden pions that raise due to dynamical chiral symmetry breaking. They are produced from the decay of inflaton. Unfortunately, it will be impossible to directly detect them, because they are super heavy (109 ∼ 12 GeV), and moreover the interaction with the visible sector is extremely suppressed.


2009 ◽  
Vol 680 (1) ◽  
pp. 88-93 ◽  
Author(s):  
Shrihari Gopalakrishna ◽  
Seung J. Lee ◽  
James D. Wells

2021 ◽  
Vol 2021 (12) ◽  
Author(s):  
Amin Aboubrahim ◽  
Pran Nath ◽  
Zhu-Yao Wang

Abstract Analysis of EDGES data shows an absorption signal of the redshifted 21-cm line of atomic hydrogen at z ∼ 17 which is stronger than expected from the standard ΛCDM model. The absorption signal interpreted as brightness temperature T21 of the 21-cm line gives an amplitude of $$ -{500}_{-500}^{+200} $$ − 500 − 500 + 200 mK at 99% C.L. which is a 3.8σ deviation from what the standard ΛCDM cosmology gives. We present a particle physics model for the baryon cooling where a fraction of the dark matter resides in the hidden sector with a U(1) gauge symmetry and a Stueckelberg mechanism operates mixing the visible and the hidden sectors with the hidden sector consisting of dark Dirac fermions and dark photons. The Stueckelberg mass mixing mechanism automatically generates a millicharge for the hidden sector dark fermions providing a theoretical basis for using millicharged dark matter to produce the desired cooling of baryons seen by EDGES by scattering from millicharged dark matter. We compute the relic density of the millicharged dark matter by solving a set of coupled equations for the dark fermion and dark photon yields and for the temperature ratio of the hidden sector and the visible sector heat baths. For the analysis of baryon cooling, we analyze the evolution equations for the temperatures of baryons and millicharged dark matter as a function of the redshift. We exhibit regions of the parameter space which allow consistency with the EDGES data. We note that the Stueckelberg mechanism arises naturally in strings and the existence of a millicharge would point to its string origin.


2021 ◽  
Vol 81 (8) ◽  
Author(s):  
Amin Aboubrahim ◽  
Tarek Ibrahim ◽  
Michael Klasen ◽  
Pran Nath

AbstractIt is shown that a decaying neutralino in a supergravity unified framework is a viable candidate for dark matter. Such a situation arises in the presence of a hidden sector with ultraweak couplings to the visible sector where the neutralino can decay into the hidden sector’s lightest supersymmetric particle (LSP) with a lifetime larger than the lifetime of the universe. We present a concrete model where the MSSM/SUGRA is extended to include a hidden sector comprised of $$U(1)_{X_1} \times U(1)_{X_2}$$ U ( 1 ) X 1 × U ( 1 ) X 2 gauge sector and the LSP of the hidden sector is a neutralino which is lighter than the LSP neutralino of the visible sector. We compute the loop suppressed radiative decay of the visible sector neutralino into the neutralino of the hidden sector and show that the decay can occur with a lifetime larger than the age of the universe. The decaying neutralino can be probed by indirect detection experiments, specifically by its signature decay into the hidden sector neutralino and an energetic gamma ray photon. Such a gamma ray can be searched for with improved sensitivity at Fermi-LAT and by future experiments such as the Square Kilometer Array (SKA) and the Cherenkov Telescope Array (CTA). We present several benchmarks which have a natural suppression of the hadronic channels from dark matter annihilation and decays and consistent with measurements of the antiproton background.


2016 ◽  
Vol 31 (18) ◽  
pp. 1630027
Author(s):  
Ikuo S. Sogami

With multi-spinor fields which behave as triple-tensor products of the Dirac spinors, the Standard Model is extended so as to embrace three families of ordinary quarks and leptons in the visible sector and an additional family of exotic quarks and leptons in the dark sector of our Universe. Apart from the gauge and Higgs fields of the Standard Model symmetry G, new gauge and Higgs fields of a symmetry isomorphic to G are postulated to exist in the dark sector. It is the bi-quadratic interaction between visible and dark Higgs fields that opens a main portal to the dark sector. Breakdowns of the visible and dark electroweak symmetries result in the Higgs boson with mass 125 GeV and a new boson which can be related to the diphoton excess around 750 GeV. Subsequent to a common inflationary phase and a reheating period, the visible and dark sectors follow weakly-interacting paths of thermal histories. We propose scenarios for dark matter in which no dark nuclear reaction takes place. A candidate for the main component of the dark matter is a stable dark hadron with spin 3/2, and the upper limit of its mass is estimated to be 15.1 GeV/c2.


2012 ◽  
Vol 86 (3) ◽  
Author(s):  
Bumseok Kyae ◽  
Jong-Chul Park
Keyword(s):  

2008 ◽  
Vol 23 (39) ◽  
pp. 3271-3283 ◽  
Author(s):  
HYE-SUNG LEE

Supersymmetry is one of the best motivated new physics scenarios. To build a realistic supersymmetric standard model, however, a companion symmetry is necessary to address various issues. While R-parity is a popular candidate that can address the proton and dark matter issues simultaneously, it is not the only option for such a property. We review how a TeV scale U(1)′ gauge symmetry can replace the R-parity. Discrete symmetries of the U(1)′ can make the model still viable and attractive with distinguishable phenomenology. For instance, with a residual discrete symmetry of the U(1)′, Z6 = B3 × U2, the proton can be protected by the baryon triality (B3) and a hidden sector dark matter candidate can be protected by the U-parity (U2).


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