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We study the discovery prospects of leptophilic dark matter (DM) in future lepton colliders by considering the light neutrinos to be of Dirac type. Adopting an effective field theory (EFT) approach, we write down dimension six operators…

High Energy Physics - Phenomenology · Physics 2025-11-14 Debasish Borah , Nayan Das , Sahabub Jahedi , Bhavya Thacker

We investigate the influence of ideal Fermi gas dark matter on the observable properties of neutron stars (NSs). Our analysis considers dark matter (DM) particle masses ($\mu$) ranging from $0.2$ GeV to $1$ GeV and various DM mass fractions…

General Relativity and Quantum Cosmology · Physics 2026-03-24 Monmoy Molla , Masum Murshid , Mehedi Kalam

In this talk, we discuss the physics modelling of particle spectra arising from dark matter (DM) annihilation or decay. In the context of the indirect searches of DM, the final state products will, in general, undergo a set of complicated…

High Energy Physics - Phenomenology · Physics 2020-12-17 Simone Amoroso , Sascha Caron , Adil Jueid , Roberto Ruiz de Austri , Peter Skands

Recent results from PAMELA and ATIC hint that O(TeV) dark matter (DM) is annihilating, in our galactic neighborhood, predominantly to leptons. The annihilation rate is much larger now than during freeze-out, one possible explanation of this…

High Energy Physics - Phenomenology · Physics 2009-05-29 Cedric Delaunay , Patrick J. Fox , Gilad Perez

Spectral functions of the nucleon and its negative parity excited state in nuclear matter are studied using QCD sum rules and the maximum entropy method (MEM). It is found that in-medium modifications of the spectral functions are…

High Energy Physics - Phenomenology · Physics 2016-10-14 Keisuke Ohtani , Philipp Gubler , Makoto Oka

We show that a thermal relic which decouples from the standard model (SM) plasma while relativistic can be a viable dark matter (DM) candidate, if the decoupling is followed by a period of entropy dilution that heats up the SM, but not the…

High Energy Physics - Phenomenology · Physics 2020-03-18 Jared A. Evans , Akshay Ghalsasi , Stefania Gori , Michele Tammaro , Jure Zupan

We examine the impact of electromagnetic properties of neutrinos on the annihilation of relic neutrinos with ultra high energy cosmic neutrinos for the $\nu \bar{\nu}\to \gamma\gamma$ process. For this process, photon-neutrino decoupling…

High Energy Physics - Phenomenology · Physics 2013-01-03 S. C. Inan , M. Koksal

Dark matter and neutrinos provide the two most compelling pieces of evidence for new physics beyond the Standard Model of Particle Physics but they are often treated as two different sectors. In this paper, we consider how neutrino…

High Energy Physics - Phenomenology · Physics 2018-05-28 Andres Olivares-Del Campo , Sergio Palomares-Ruiz , Silvia Pascoli

We present generic formulae for computing how Sommerfeld corrections together with bound-state formation affects the thermal abundance of Dark Matter with non-abelian gauge interactions. We consider DM as a fermion 3plet (wino) or 5plet…

High Energy Physics - Phenomenology · Physics 2018-07-09 Andrea Mitridate , Michele Redi , Juri Smirnov , Alessandro Strumia

We consider a model of dark matter where the mediator corresponds to a superposition of a scalar and pseudoscalar, and the scenario where, after reheating, the number densities of the dark sector particles, i.e. the dark matter and the…

High Energy Physics - Phenomenology · Physics 2025-11-19 Geneviève Bélanger , Aoife Bharucha , Sreemanti Chakraborti , Rashidul Islam , Sophie Mutzel

Sterile neutrinos with masses in the keV range are well-motivated extensions to the Standard Model that could explain the observed neutrino masses while also making up the dark matter (DM) of the Universe. If sterile neutrinos are DM then…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-04 Joshua W. Foster , Marius Kongsore , Christopher Dessert , Yujin Park , Nicholas L. Rodd , Kyle Cranmer , Benjamin R. Safdi

Dark matter may accumulate in neutron stars given its gravitational interaction and abundance. We investigate the influence of strongly-interacting dark matter, described by a QCD-like one-flavor $G_2$ gauge theory, on neutron stars. This…

High Energy Physics - Phenomenology · Physics 2026-04-08 Yannick Dengler , Suchita Kulkarni , Axel Maas , Kevin Radl

We present a novel candidate for cold dark matter consisting of condensed Cooper pairs in a theory of interacting fermions with broken chiral symmetry. Establishing the thermal history from the early radiation era to the present, the…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-26 Guanming Liang

Due to their extreme density and low temperature, neutron stars (NS) are efficient probes to unveil interactions between standard model and dark matter (DM) particles. From elastic scatterings on NS material, DM can get gravitationally…

High Energy Physics - Phenomenology · Physics 2019-05-28 Raghuveer Garani , Yoann Genolini , Thomas Hambye

We study a scenario where a dark sector, described by a Conformal Field Theory (CFT), interacts with the Standard Model through the neutrino portal. In this setup, conformal invariance breaks below the electroweak scale, causing the theory…

High Energy Physics - Phenomenology · Physics 2024-12-03 Sungwoo Hong , Maxim Perelstein , Taewook Youn

In a usual dark matter (DM) model without a huge mass difference between the DM and lighter mediator, using the coupling strength suitable for having the correct relic density, the resulting self-interaction becomes several orders of…

High Energy Physics - Phenomenology · Physics 2024-04-04 Kwei-Chou Yang

Self-Interacting Dark Matter models can successfully explain dark matter (DM) production through interactions confined within the dark sector. However, they often lack measurable experimental signals due to their secluded nature. Including…

High Energy Physics - Phenomenology · Physics 2025-01-16 Esau Cervantes , Andrzej Hryczuk

We consider, in a model-independent framework, the potential for observing dark matter in neutrino detectors through the interaction $\bar{f} p \to e^+ n$, where $f$ is a dark fermion. Operators of dimension six or less are considered, and…

High Energy Physics - Phenomenology · Physics 2009-10-19 Jennifer Kile

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…

High Energy Physics - Phenomenology · Physics 2018-01-17 Nagisa Hiroshima , Ryuichiro Kitano , Kazunori Kohri , Kohta Murase

In this paper, we analyze the cosmological evolution, allowed parameter space, and observational prospects for a dark sector consisting of thermally produced pseudo-Dirac fermions with a small mass splitting, coupled to the Standard Model…

High Energy Physics - Phenomenology · Physics 2021-09-02 Mariana Carrillo González , Natalia Toro