HOW SUPERCRITICAL STRING COSMOLOGY AFFECTS LHC

2010 ◽  
Vol 25 (40) ◽  
pp. 3335-3346
Author(s):  
D. V. NANOPOULOS
Keyword(s):  
Dark Matter ◽  
Parameter Space ◽  
Z Bosons ◽  
High Energy ◽  
String Cosmology ◽  
Matter Content ◽  
Higgs Bosons ◽  
Model Parameters ◽  
Final States ◽  
Dark Matter Relic Density

In supercritical string cosmology (SSC), a time-dependent dilaton leads to a smoothly evolving dark energy and modifies the regions of the mSUGRA parameter space where the observed value of the dark matter relic density may be obtained. In particular, the dilaton dilutes the supersymmetric dark matter density (of neutralinos) by a factor [Formula: see text] and consequently relaxes the allowed parameter mSUGRA parameter space. The final states expected at the LHC in this scenario, consist of Z bosons, Higgs bosons, and/or high energy taus. From this, it is possible to characterize these final states and determine the model parameters. Using these parameters, we determine the dark matter content and the neutralino–proton cross section. All these techniques can also be applied to determine model parameters in SSC models with different SUSY breaking scenarios.

scholarly journals SUSY DARK MATTER IN LIGHT OF CDMS/XENON LIMITS

2011 ◽  
Vol 20 (08) ◽  
pp. 1383-1388 ◽  
Author(s):  
JIN MIN YANG
Keyword(s):  
Dark Matter ◽  
Higgs Boson ◽  
Parameter Space ◽  
Charged Higgs Boson ◽  
Higgs Bosons ◽  
Dark Matter Relic Density ◽  
Higgs Search ◽  
Relic Density ◽  
Supersymmetric Models ◽  
Charged Higgs

We briefly review the current CDMS/XENON constraints on the neutralino dark matter in three popular supersymmetric models: the minimal (MSSM), the next-to-minimal (NMSSM) and the nearly minimal (nMSSM). The constraints from the dark matter relic density and various collider experiments are also taken into account. The conclusion is that for each model the current CDMS/XENON limits can readily exclude a large part of the parameter space allowed by other constraints and the future SuperCDMS or XENON100 can cover most of the allowed parameter space. The implication for the Higgs search at the LHC is also discussed. It is found that in the currently allowed parameter space the MSSM charged Higgs boson is quite unlikely to be discovered at the LHC while the neutral Higgs bosons H and A may be accessible at the LHC in the parameter space with a large μ parameter.

scholarly journals Constraining the Inert Doublet Model using Vector Boson Fusion

2019 ◽  
Vol 79 (11) ◽  
Author(s):  
Daniel Dercks ◽  
Tania Robens
Keyword(s):  
Dark Matter ◽  
Parameter Space ◽  
Vector Boson ◽  
Higgs Doublet ◽  
Dark Matter Candidate ◽  
Final States ◽  
Vector Boson Fusion ◽  
Doublet Model ◽  
Inert Doublet Model ◽  
Two Higgs Doublet Model

AbstractIn this work, we use a recast of the Run II search for invisible Higgs decays within Vector Boson Fusion to constrain the parameter space of the Inert Doublet model, a two Higgs doublet model with a dark matter candidate. When including all known theoretical as well as collider constraints, we find that the above can rule out a relatively large part in the $$m_H,\,\lambda _{345}$$mH,λ345 parameter space, for dark scalar masses $$m_H\,\le \,100\,{\mathrm{GeV}}$$mH≤100GeV. Including the latest dark matter constraints, a smaller part of parameter space remains which is solely excluded from the above analysis. We also discuss the sensitivity of monojet searches and multilepton final states from Run II.

SEARCH FOR CHARGED HIGGS BOSONS IN E+E- COLLISIONS AT LEP AT THE DELPHI EXPERIMENT

2001 ◽  
Vol 16 (supp01b) ◽  
pp. 839-842
Author(s):  
◽  
G. Gómez-Ceballos
Keyword(s):  
Higgs Boson ◽  
High Energy ◽  
Higgs Bosons ◽  
Final States ◽  
Centre Of Mass ◽  
Energy Data ◽  
Delphi Detector ◽  
Charged Higgs ◽  
Delphi Experiment ◽  
Charged Higgs Bosons

A search for pair produced charged Higgs bosons was performed in the high energy data collected by the DELPHI detector at LEP II at centre-of-mass energies from 183 GeV to 208 GeV. The three different final states, τντν, [Formula: see text] and [Formula: see text] were considered. No excess of data compared to the expected Standard Model processes was observed and the existence of a charged Higgs boson with mass lower than 75.0 GeV / c 2 is excluded at 95% confidence level.

scholarly journals Imprint of Pressure on Characteristic Dark Matter Profiles: The Case of ESO0140040

Galaxies ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 74
Author(s):  
Kuantay Boshkayev ◽  
Talgar Konysbayev ◽  
Ergali Kurmanov ◽  
Orlando Luongo ◽  
Marco Muccino
Keyword(s):  
Dark Matter ◽  
Complex Structure ◽  
Matter Content ◽  
Model Parameters ◽  
Matter Distribution ◽  
Density Profiles ◽  
The Galaxy ◽  
Dark Matter Distribution ◽  
Observational Signature

We investigate the dark matter distribution in the spiral galaxy ESO0140040, employing the most widely used density profiles: the pseudo-isothermal, exponential sphere, Burkert, Navarro-Frenk-White, Moore and Einasto profiles. We infer the model parameters and estimate the total dark matter content from the rotation curve data. For simplicity, we assume that dark matter distribution is spherically symmetric without accounting for the complex structure of the galaxy. Our predictions are compared with previous results and the fitted parameters are statistically confronted for each profile. We thus show that although one does not include the galaxy structure it is possible to account for the same dynamics assuming that dark matter provides a non-zero pressure in the Newtonian approximation. In this respect, we solve the hydrostatic equilibrium equation and construct the dark matter pressure as a function for each profile. Consequently, we discuss the dark matter equation of state and calculate the speed of sound in dark matter. Furthermore, we interpret our results in view of our approach and we discuss the role of the refractive index as an observational signature to discriminate between our approach and the standard one.

scholarly journals Precision SMEFT bounds from the VBF Higgs at high transverse momentum

2021 ◽  
Vol 2021 (4) ◽  
Author(s):  
Jack Y. Araz ◽  
Shankha Banerjee ◽  
Rick S. Gupta ◽  
Michael Spannowsky
Keyword(s):  
Standard Model ◽  
Vector Boson ◽  
High Energy ◽  
Effective Field ◽  
Higgs Bosons ◽  
Quadratic Growth ◽  
Final States ◽  
High Transverse Momentum ◽  
The Standard Model ◽  
Independent Operator

Abstract We study the production of Higgs bosons at high transverse momenta via vector-boson fusion (VBF) in the Standard Model Effective Field Theory (SMEFT). We find that contributions from four independent operator combinations dominate in this limit. These are the same ‘high energy primaries’ that control high energy diboson processes, including Higgs-strahlung. We perform detailed collider simulations for the diphoton decay mode of the Higgs boson as well as the three final states arising from the ditau channel. Using the quadratic growth of the SMEFT contributions relative to the Standard Model (SM) contribution, we project very stringent bounds on these operators that far surpass the corresponding bounds from the LEP experiment.

Searches for new, massive particles with AMO experiments

2019 ◽  
pp. 29-81
Author(s):  
David DeMille
Keyword(s):  
Dark Matter ◽  
Cp Violation ◽  
Particle Physics ◽  
High Energy ◽  
Higgs Bosons ◽  
Substantial Impact ◽  
Molecular Hamiltonian ◽  
Physics Experiments ◽  
Pedagogical Goal ◽  
New Particles

These lectures aim to explain how certain types of atomic, molecular, and optical physics experiments can have a substantial impact in modern particle physics. A central pedagogical goal is to describe, using only concepts familiar to atomic experimentalists, how new particles can lead to new terms in the atomic or molecular Hamiltonian. Well-motivated examples are discussed, including potential dark matter candidates known as “dark photons”, known and as-yet unknown Higgs bosons, and supersymmetric particles leading to CP violation. The observable effects of new Hamiltonian terms associated with these phenomena are worked out, and state-of-the-art strategies for detecting them, using atomic and molecular experiments, are described for some cases. Remarkably, the sensitivity of atomic/molecular experiments can make it possible to detect new particles even more massive than those that can be created directly at the largest high-energy colliders.

scholarly journals A Comparative Study of Dark Matter in the MSSM and Its Singlet Extensions: A Mini Review

2012 ◽  
Vol 2012 ◽  
pp. 1-22 ◽  
Author(s):  
Wenyu Wang
Keyword(s):  
Dark Matter ◽  
Higgs Boson ◽  
Comparative Study ◽  
Parameter Space ◽  
Light Neutralino ◽  
Dark Matter Relic Density ◽  
Relic Density ◽  
The Future

In this note we briefly review the recent studies of dark matter in the MSSM and its singlet extensions: the NMSSM, the nMSSM, and the general singlet extension. Under the new detection results of CDMS II, XENON, CoGeNT, and PAMELA, we find that (i) the latest detection results can exclude a large part of the parameter space which is allowed by current collider constraints in these models. The future SuperCDMS and XENON can cover most of the allowed parameter space; (ii) the singlet sector will decouple from the MSSM-like sector in the NMSSM; however, singlet sector makes the nMSSM quite different from the MSSM; (iii) the NMSSM can allow light dark matter at several GeV to exist. Light CP-even or CP-odd Higgs boson must be present so as to satisfy the measured dark matter relic density. In case of the presence of a light CP-even Higgs boson, the light neutralino dark matter can explain the CoGeNT and DAMA/LIBRA results; (iv) the general singlet extension of the MSSM gives a perfect explanation for both the relic density and the PAMELA result through the Sommerfeld-enhanced annihilation. Higgs decays in different scenario are also studied.

scholarly journals Relativistic freeze-in with scalar dark matter in a gauged B − L model and electroweak symmetry breaking

2021 ◽  
Vol 2021 (5) ◽  
Author(s):  
Priyotosh Bandyopadhyay ◽  
Manimala Mitra ◽  
Abhishek Roy
Keyword(s):  
Dark Matter ◽  
Higgs Boson ◽  
Symmetry Breaking ◽  
Electroweak Symmetry Breaking ◽  
Higgs Bosons ◽  
Thermal Mass ◽  
Electroweak Symmetry ◽  
Mass Correction ◽  
Dark Matter Relic Density ◽  
Bose Einstein

Abstract We explore relativistic freeze-in production of scalar dark matter in gauged B − L model, where we focus on the production of dark matter from the decay and annihilation of Standard Model (SM) and B − L Higgs bosons. We consider the Bose-Einstein (BE) and Fermi-Dirac (FD) statistics, along with the thermal mass correction of the SM Higgs boson in our analysis. We show that in addition to the SM Higgs boson, the annihilation and decay of the B − L scalar can also contribute substantially to the dark matter relic density. Potential effects of electroweak symmetry breaking (EWSB) and thermal mass correction in BE framework enhance the dark matter relic substantially as it freezes-in near EWSB temperature via scalar annihilation. However, such effects are not so prominent when the dark matter freezes-in at a later epoch than EWSB, dominantly by decay of scalars. The results of this analysis are rather generic, and applicable to other similar scenarios.

scholarly journals Dark Matter Constraints and the Neutralino Sector of the scNMSSM

Universe ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 31
Author(s):  
Elham Aldufeery ◽  
Maien Binjonaid
Keyword(s):  
Dark Matter ◽  
Parameter Space ◽  
Cross Sections ◽  
Direct Detection ◽  
Mass Range ◽  
Upper And Lower Bounds ◽  
Dark Matter Candidate ◽  
Dark Matter Relic Density ◽  
Relic Density ◽  
Moderate Range

The neutralino sector of the semi-constrained next-to-minimal supersymmetric standard model is explored under recent experimental constraints, with special attention to dark matter (DM) limits. The effects of the upper and lower bounds of dark matter relic density and recent direct detection constraints on spin-independent and -dependent cross-sections are thoroughly analyzed. Particularly, we show which regions of the parameter space are ruled out due to the different dark matter constraints and the corresponding model-specific parameters: λ,κ,Aλ, and Aκ. We analyze all annihilation and co-annihilation processes (with heavier neutralinos and charginos) that contribute to the dark matter relic density. The mass components of the dark matter candidate, the lightest neutralino χ˜10, are studied, and the decays of heavy neutralinos and charginos, especially χ˜20 and χ˜1+, into the lightest neutralino are examined. We impose semi-universal boundary conditions at the Grand Unified Theory scale, and require a moderate range of tanβ≲10. We find that the allowed parameter space is associated with a heavy mass spectrum in general and that the lightest neutralino is mostly Higgsino with a mass range that resides mostly between 1000 and 1500 GeV. However, smaller mass values can be achieved if the DM candidate is bino-like or singlino-like.

scholarly journals Latest results on dark matter searches with H.E.S.S

2019 ◽  
Vol 209 ◽  
pp. 01023 ◽  
Author(s):  
Lucia Rinchiuso
Keyword(s):  
Dark Matter ◽  
Dwarf Galaxies ◽  
Dwarf Galaxy ◽  
Mass Range ◽  
High Energy ◽  
Galactic Centre ◽  
Final States ◽  
Cherenkov Telescopes ◽  
Observation Strategy ◽  
Very High Energy

The nature of Dark Matter (DM) is one of the most debated questions of contemporary physics. Ground-based arrays of Cherenkov telescopes such as the High Energy Spectroscopic System (H.E.S.S.) search for DM signatures through the detection of Very-High-Energy (VHE, E > 100 GeV) gamma-rays. DM particles could selfannihilate in dense environments producing VHE γ-rays in the final states that could be eventually detected by H.E.S.S.. The H.E.S.S. observation strategy for DM search focuses towards the Galactic Centre (GC) region and nearby dwarf galaxy satellites of the Milky Way. The GC dataset provides the most stringent constraints on the DM annihilation cross section in the mass range 300 GeV - 70 TeV. Searches have been carried out towards classical and ultra-faint dwarf galaxies to test specific heavy DM models. The latest results towards the GC and dwarf galaxies are shown.

Sign in / Sign up

Export Citation Format

Share Document