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Related papers: $\mathbf{{N}_{eff}}$ from Excited DM state

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The decay and annihilation cross sections of dark matter particles may depend on the value of a chameleonic scalar field that both evolves cosmologically and takes different values depending on the local matter density. This possibility…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 Kimberly K. Boddy , Sean M. Carroll , Mark Trodden

Kinetic heating of old cold neutron stars, via the scattering of dark matter with matter in the star, provides a promising way to probe the nature of dark matter interactions. We consider a dark matter candidate that is a Standard Model…

High Energy Physics - Phenomenology · Physics 2025-10-24 Nicole F. Bell , Giorgio Busoni , Avirup Ghosh

The naturalness problem of PQ symmetry motivates study of the heavy QCD axion, with masses $m_a >$ 1 MeV generated at scales above the QCD scale, and low values of the PQ symmetry breaking scale, $f_a$. We compute the abundance of such…

High Energy Physics - Phenomenology · Physics 2022-05-25 David I. Dunsky , Lawrence J. Hall , Keisuke Harigaya

We present a comprehensive framework for interpreting electron recoil signals induced by fast-moving dark matter (DM), applicable across a wide range of theoretically motivated models. Amid both null results in conventional weakly…

High Energy Physics - Phenomenology · Physics 2025-11-07 Haider Alhazmi , Doojin Kim , Kyoungchul Kong , Aishah Sumayli

The neutron-deficient nucleus 173Hg has been studied following fusion-evaporation reactions. The observation of gamma rays decaying from excited states are reported for the first time and a tentative level scheme is proposed. The proposed…

The stable hadronic bound states in a hidden new non-Abelian gauge sector provide interesting candidates for strongly-interacting Dark Matter (DM). A particular example are theories in which DM is made up of dark pions which set the DM…

High Energy Physics - Phenomenology · Physics 2023-01-11 Fabian Zierler , Suchita Kulkarni , Axel Maas , Seán Mee , Marco Nikolic , Josef Pradler

Dark matter (DM) is added to the Froggatt-Nielsen (FN) mechanism, and conditions for its successful freezeout identified. Requesting the FN scale $\Lambda_{\text{FN}}$ to be the cutoff of the theory renders freezeout scenarios surprisingly…

High Energy Physics - Phenomenology · Physics 2017-10-04 Carlos Alvarado , Fatemeh Elahi , Nirmal Raj

The acoustic peaks in the angular power spectrum of cosmic microwave background (CMB) temperature and polarization anisotropies play an important role as a probe of the nature of new relativistic particles contributing to the radiation…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-03 Gongjun Choi , Chi-Ting Chiang , Marilena LoVerde

We study phenomenology of electroweak-interacting fermionic dark matter (DM) with a mass of $\mathcal{O}(100)$ GeV. Constructing the effective Lagrangian that describes the interactions between the Higgs boson and the SU(2)$_L$ isospin…

High Energy Physics - Phenomenology · Physics 2015-02-03 Junji Hisano , Daiki Kobayashi , Naoya Mori , Eibun Senaha

In this paper we consider a spin-$\frac{3}{2}$ dark matter (DM) particle coupled to neutrinos as a viable candidate to produce the observed DM relic density through the thermal freeze-out mechanism. The couplings of DM to neutrinos is…

High Energy Physics - Phenomenology · Physics 2022-11-09 Ashok Goyal , Mohammed Omer Khojali , Mukesh Kumar , Alan S. Cornell

We consider inelastic dark matter scenarios with dark photon mediator and a dark Higgs boson. The dark Higgs boson spontaneously breaks the gauge symmetry associated with the dark photon, and gives the mass to the dark photon and the mass…

High Energy Physics - Phenomenology · Physics 2022-10-19 Jinmian Li , Takaaki Nomura , Takashi Shimomura

In this work, we make a detailed discussion on the phenomenology of the scotogenic Dirac model, which could accommodate the Dirac neutrino mass and dark matter. We have studied the LFV processes in this model, which are mediated by the…

High Energy Physics - Phenomenology · Physics 2020-12-11 Shu-Yuan Guo , Zhi-Long Han

Planned CMB Stage IV experiments have the potential to measure the effective number of relativistic degrees of freedom in the early Universe, $N_\text{eff}$, with percent-level accuracy. This probes new thermalized light particles and also…

High Energy Physics - Phenomenology · Physics 2019-10-25 Kevork N. Abazajian , Julian Heeck

We consider a cosmological model in which a fraction $f$ of the Dark Matter (DM) is allowed to decay in an invisible relativistic component, and compute the resulting constraints on both the decay width (or inverse lifetime) $\Gamma$ and…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-31 Vivian Poulin , Pasquale D. Serpico , Julien Lesgourgues

In interacting multi-component dark matter (DM) models, if the DM components are nearly degenerate in mass and the interactions between them are strong enough, the relatively heavy DM components can be converted into lighter ones at late…

High Energy Physics - Phenomenology · Physics 2015-06-03 Ze-Peng Liu , Yue-Liang Wu , Yu-Feng Zhou

We studied the effects of the absolute neutrino mass scale in the scotogenic radiative seesaw model. From a scan over the parameter space of this model, a linear relation between the absolute neutrino mass and the dark sector-Higgs coupling…

High Energy Physics - Phenomenology · Physics 2021-05-03 Thede de Boer , Michael Klasen , Caroline Rodenbeck , Sybrand Zeinstra

We study the possibility of generating light Dirac neutrino mass via scotogenic mechanism where singlet-doublet fermion dark matter (DM) plays non-trivial role in generating one-loop neutrino mass, anomalous magnetic moment of muon…

High Energy Physics - Phenomenology · Physics 2024-04-19 Debasish Borah , Satyabrata Mahapatra , Dibyendu Nanda , Sujit Kumar Sahoo , Narendra Sahu

We show that a Dirac right-handed scalar neutrino can be weakly interacting massive particle in the neutrinophilic Higgs model. When the additional Higgs fields couple only to the leptonic sector through neutrino Yukawa couplings, the right…

High Energy Physics - Phenomenology · Physics 2015-06-05 Ki-Young Choi , Osamu Seto

We constrain the parameters of a representative new physics model with possible dark matter (DM) signature from a global CKM fit analysis. The model has neutral quark current interactions mediated by a scalar, impacting the semileptonic and…

High Energy Physics - Phenomenology · Physics 2023-03-07 Aritra Biswas , Lopamudra Mukherjee , Soumitra Nandi , Sunando Kumar Patra

We investigate the effects of dark matter (DM) on neutron star (NS) properties using the neutron decay anomaly model within the relativistic mean-field (RMF) framework. Three nucleonic models (HCD0-HCD2) are developed, satisfying…

High Energy Astrophysical Phenomena · Physics 2025-05-15 H. C. Das , G. F. Burgio