scholarly journals Dark QCD matters

2021 ◽  
Vol 2021 (12) ◽  
Author(s):  
Raghuveer Garani ◽  
Michele Redi ◽  
Andrea Tesi
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Structure Formation ◽  
Gauge Theories ◽  
Initial Temperature ◽  
Pion Mass ◽  
Dark Sector ◽  
Abelian Gauge ◽  
The Standard Model

Abstract We investigate the nightmare scenario of dark sectors that are made of non-abelian gauge theories with fermions, gravitationally coupled to the Standard Model (SM). While testing these scenarios is experimentally challenging, they are strongly motivated by the accidental stability of dark baryons and pions, that explain the cosmological stability of dark matter (DM). We study the production of these sectors which are minimally populated through gravitational freeze-in, leading to a dark sector temperature much lower than the SM, or through inflaton decay, or renormalizable interactions producing warmer DM. Despite having only gravitational couplings with the SM these scenarios turn out to be rather predictive depending roughly on three parameters: the dark sector temperature, the confinement scale and the dark pion mass. In particular, when the initial temperature is comparable to the SM one these scenarios are very constrained by structure formation, ∆Neff and limits on DM self-interactions. Dark sectors with same temperature or warmer than SM are typically excluded.

Extension of Standard Model in multi-spinor field formalism — Visible and dark sectors

2016 ◽  
Vol 31 (18) ◽  
pp. 1630027
Author(s):  
Ikuo S. Sogami
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Dark Sector ◽  
Quadratic Interaction ◽  
Inflationary Phase ◽  
The Standard Model ◽  
Visible Sector ◽  
Field Formalism ◽  
Main Component ◽  
Higgs Fields

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.

scholarly journals Finite field-dependent BRST–anti-BRST transformations: Jacobians and application to the Standard Model

2016 ◽  
Vol 31 (20n21) ◽  
pp. 1650111 ◽  
Author(s):  
Pavel Yu. Moshin ◽  
Alexander A. Reshetnyak
Keyword(s):  
Standard Model ◽  
Gauge Theories ◽  
Landau Gauge ◽  
Gauge Fields ◽  
Nontrivial Solutions ◽  
Abelian Gauge ◽  
The Standard Model ◽  
Field Dependent ◽  
Quantum Action ◽  
General Gauge

We continue our research[Formula: see text] and extend the class of finite BRST–anti-BRST transformations with odd-valued parameters [Formula: see text], [Formula: see text], introduced in these works. In doing so, we evaluate the Jacobians induced by finite BRST–anti-BRST transformations linear in functionally-dependent parameters, as well as those induced by finite BRST–anti-BRST transformations with arbitrary functional parameters. The calculations cover the cases of gauge theories with a closed algebra, dynamical systems with first-class constraints, and general gauge theories. The resulting Jacobians in the case of linearized transformations are different from those in the case of polynomial dependence on the parameters. Finite BRST–anti-BRST transformations with arbitrary parameters induce an extra contribution to the quantum action, which cannot be absorbed into a change of the gauge. These transformations include an extended case of functionally-dependent parameters that implies a modified compensation equation, which admits nontrivial solutions leading to a Jacobian equal to unity. Finite BRST–anti-BRST transformations with functionally-dependent parameters are applied to the Standard Model, and an explicit form of functionally-dependent parameters [Formula: see text] is obtained, providing the equivalence of path integrals in any 3-parameter [Formula: see text]-like gauges. The Gribov–Zwanziger theory is extended to the case of the Standard Model, and a form of the Gribov horizon functional is suggested in the Landau gauge, as well as in [Formula: see text]-like gauges, in a gauge-independent way using field-dependent BRST–anti-BRST transformations, and in [Formula: see text]-like gauges using transverse-like non-Abelian gauge fields.

scholarly journals Collider signatures of coannihilating dark matter in light of the B-physics anomalies

2021 ◽  
Vol 2021 (11) ◽  
Author(s):  
Michael J. Baker ◽  
Darius A. Faroughy ◽  
Sokratis Trifinopoulos
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Bound States ◽  
B Physics ◽  
Search Strategy ◽  
Dark Matter Candidate ◽  
Final States ◽  
Dark Sector ◽  
Decay Modes ◽  
The Standard Model

Abstract Motivated by UV explanations of the B-physics anomalies, we study a dark sector containing a Majorana dark matter candidate and a coloured coannihilation partner, connected to the Standard Model predominantly via a U1 vector leptoquark. A TeV scale U1 leptoquark, which couples mostly to third generation fermions, is the only successful single-mediator description of the B-physics anomalies. After calculating the dark matter relic surface, we focus on the most promising experimental avenue: LHC searches for the coloured coannihilation partner. We find that the coloured partner hadronizes and forms meson-like bound states leading to resonant signatures at colliders reminiscent of the quarkonia decay modes in the Standard Model. By recasting existing dilepton and monojet searches we exclude coannihilation partner masses less than 280 GeV and 400 GeV, respectively. Since other existing collider searches do not significantly probe the parameter space, we propose a new dedicated search strategy for pair production of the coloured partner decaying into bbττ final states and dark matter particles. This search is expected to probe the model up to dark matter masses around 600 GeV with current luminosity.

scholarly journals Observing the Dark Sector

Universe ◽  
2019 ◽  
Vol 5 (6) ◽  
pp. 137
Author(s):  
Valerio Marra ◽  
Rogerio Rosenfeld ◽  
Riccardo Sturani
Keyword(s):  
General Relativity ◽  
Dark Matter ◽  
Dark Energy ◽  
Standard Model ◽  
Dark Sector ◽  
The Standard Model

Despite the observational success of the standard model of cosmology, present-day observations do not tightly constrain the nature of dark matter and dark energy and modifications to the theory of general relativity. Here, we will discuss some of the ongoing and upcoming surveys that will revolutionize our understanding of the dark sector.

scholarly journals DARK MATTER CANDIDATE FROM CONFORMALITY

2007 ◽  
Vol 22 (13) ◽  
pp. 931-937 ◽  
Author(s):  
P. H. FRAMPTON
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Cross Section ◽  
Weak Interaction ◽  
Gauge Theories ◽  
Dark Matter Candidate ◽  
Beyond The Standard Model ◽  
The Standard Model ◽  
Relic Density ◽  
Baryonic Dark Matter

Abelian quiver gauge theories provide candidates for the conformality approach to physics beyond the standard model which possess novel cancellation mechanisms for quadratic divergences. A Z2 symmetry ( R parity) can be imposed and leads naturally to a dark matter candidate which is the Lightest Conformality Particle (LCP), a neutral spin-1 / 2 state with weak interaction annihilation cross-section, mass in the 100 GeV region and relic density of non-baryonic dark matter Ωdm which can be consistent with the observed value Ωdm≃0.24.

scholarly journals SEARCHING FOR A DARK MATTER COUPLING TO THE STANDARD MODEL WITH A STUECKELBERG EXTENSION

2012 ◽  
Vol 18 ◽  
pp. 10-12
Author(s):  
A. L. DOS SANTOS ◽  
D. HADJIMICHEF
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Z Boson ◽  
Dark Sector ◽  
Minimal Coupling ◽  
Matter Coupling ◽  
The Standard Model ◽  
Double Extension ◽  
Matter Sector

We investigate a double extension to the Standard Model (SM). A first extension introduces, via minimal coupling, a massive Z′ boson. This enlarged SM is coupled to a dark matter sector through the Stueckelberg mechanism by a A′ boson. However, the A′ boson does not interact directly with the SM fermions. In our study, we found that the A′ is a massless photon-like particle in dark sector. Constraints on the mass for Z′ and corrections to Z mass are obtained.

scholarly journals Nearly Supersymmetric Dark Atoms

2011 ◽  
Vol 2011 ◽  
pp. 1-34 ◽  
Author(s):  
Siavosh R. Behbahani ◽  
Martin Jankowiak ◽  
Tomas Rube ◽  
Jay G. Wacker
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Supersymmetry Breaking ◽  
Bound States ◽  
Dark Sector ◽  
Missing Mass ◽  
The Standard Model ◽  
The Universe

Theories of dark matter that support bound states are an intriguing possibility for the identity of the missing mass of the Universe. This article proposes a class of models of supersymmetric composite dark matter where the interactions with the Standard Model communicate supersymmetry breaking to the dark sector. In these models, supersymmetry breaking can be treated as a perturbation on the spectrum of bound states. Using a general formalism, the spectrum with leading supersymmetry effects is computed without specifying the details of the binding dynamics. The interactions of the composite states with the Standard Model are computed, and several benchmark models are described. General features of nonrelativistic supersymmetric bound states are emphasized.

scholarly journals The Higgs boson and cosmology

2015 ◽  
Vol 373 (2032) ◽  
pp. 20140038 ◽  
Author(s):  
Mikhail Shaposhnikov
Keyword(s):  
Dark Matter ◽  
Higgs Boson ◽  
Standard Model ◽  
Structure Formation ◽  
Higgs Field ◽  
Big Bang ◽  
Seed Structure ◽  
Matter Production ◽  
The Standard Model ◽  
The Universe

I will discuss how the Higgs field of the Standard Model may have played an important role in cosmology, leading to the homogeneity, isotropy and flatness of the Universe; producing the quantum fluctuations that seed structure formation; triggering the radiation-dominated era of the hot Big Bang; and contributing to the processes of baryogenesis and dark matter production.

scholarly journals Gravitational vector Dark Matter

2021 ◽  
Vol 2021 (3) ◽  
Author(s):  
Christian Gross ◽  
Sotirios Karamitsos ◽  
Giacomo Landini ◽  
Alessandro Strumia
Keyword(s):  
Dark Matter ◽  
Gauge Theory ◽  
Bound States ◽  
Gauge Theories ◽  
Dark Sector ◽  
Abelian Gauge ◽  
Abelian Gauge Theory ◽  
Gravitational Vector ◽  
Relic Abundance

Abstract A new dark sector consisting of a pure non-abelian gauge theory has no renormalizable interaction with SM particles, and can thereby realise gravitational Dark Matter (DM). Gauge interactions confine at a scale ΛDM giving bound states with typical lifetimes $$ \tau \sim {M}_{\mathrm{P}1}^4/{\Lambda}_{\mathrm{DM}}^5 $$ τ ∼ M P 1 4 / Λ DM 5 that can be DM candidates if ΛDM is below 100 TeV. Furthermore, accidental symmetries of group-theoretical nature produce special gravitationally stable bound states. In the presence of generic Planck-suppressed operators such states become long-lived: SU(N) gauge theories contain bound states with $$ \tau \sim {M}_{\mathrm{P}1}^8/{\Lambda}_{\mathrm{DM}}^9 $$ τ ∼ M P 1 8 / Λ DM 9 ; even longer lifetimes τ = (MPl/ΛDM)2N−4/ΛDM arise from SO(N) theories with N ≥ 8, and possibly from F4 or E8. We compute their relic abundance generated by gravitational freeze-in and by inflationary fluctuations, finding that they can be viable DM candidates for ΛDM ≳ 1010 GeV.

Sign in / Sign up

Export Citation Format

Share Document