scholarly journals Accurate neutralino relic density computations in supergravity models

1993 ◽  
Vol 48 (6) ◽  
pp. 2766-2776 ◽  
Author(s):  
Jorge L. Lopez ◽  
D. V. Nanopoulos ◽  
Kajia Yuan
1998 ◽  
Vol 57 (5) ◽  
pp. 3131-3139 ◽  
Author(s):  
V. Barger ◽  
Chung Kao

2011 ◽  
Vol 26 (21) ◽  
pp. 1521-1535 ◽  
Author(s):  
SUJEET AKULA ◽  
DANIEL FELDMAN ◽  
ZUOWEI LIU ◽  
PRAN NATH ◽  
GREGORY PEIM

Constraints on dark matter from the first CMS and ATLAS SUSY searches are investigated. It is shown that within the minimal supergravity model, the early search for supersymmetry at the LHC has depleted a large portion of the signature space in dark matter direct detection experiments. In particular, the prospects for detecting signals of dark matter in the XENON and CDMS experiments are significantly affected in the low neutralino mass region. Here the relic density of dark matter typically arises from slepton coannihilations in the early universe. In contrast, it is found that the CMS and ATLAS analyses leave untouched the Higgs pole and the Hyperbolic Branch/Focus Point regions, which are now being probed by the most recent XENON results. Analysis is also done for supergravity models with non-universal soft breaking where one finds that a part of the dark matter signature space depleted by the CMS and ATLAS cuts in the minimal SUGRA case is repopulated. Thus, observation of dark matter in the LHC depleted region of minimal supergravity may indicate non-universalities in soft breaking.


Author(s):  
Laurent Baulieu ◽  
John Iliopoulos ◽  
Roland Sénéor

The motivation for supersymmetry. The algebra, the superspace, and the representations. Field theory models and the non-renormalisation theorems. Spontaneous and explicit breaking of super-symmetry. The generalisation of the Montonen–Olive duality conjecture in supersymmetric theories. The remarkable properties of extended supersymmetric theories. A brief discussion of twisted supersymmetry in connection with topological field theories. Attempts to build a supersymmetric extention of the standard model and its experimental consequences. The property of gauge supersymmetry to include general relativity and the supergravity models.


2021 ◽  
Vol 2021 (4) ◽  
Author(s):  
Soo-Min Choi ◽  
Hyun Min Lee ◽  
Bin Zhu

Abstract We consider a novel mechanism to realize exothermic dark matter with dark mesons in the limit of approximate flavor symmetry in a dark QCD. We introduce a local dark U(1)′ symmetry to communicate between dark mesons and the Standard Model via Z′ portal by partially gauging the dark flavor symmetry with flavor-dependent charges for cancelling chiral anomalies in the dark sector. After the dark local U(1)′ is broken spontaneously by the VEV of a dark Higgs, there appear small mass splittings between dark quarks, consequently, leading to small split masses for dark mesons, required to explain the electron recoil excess in XENON1T by the inelastic scattering between dark mesons and electron. We propose a concrete benchmark model for split dark mesons based on SU(3)L× SU(3)R/SU(3)V flavor symmetry and SU(Nc) color group and show that there exists a parameter space making a better fit to the XENON1T data with two correlated peaks from exothermic processes and satisfying the correct relic density, current experimental and theoretical constraints.


2021 ◽  
Vol 2021 (6) ◽  
Author(s):  
Andrzej Hryczuk ◽  
Maxim Laletin

Abstract We study a novel dark matter production mechanism based on the freeze-in through semi-production, i.e. the inverse semi-annihilation processes. A peculiar feature of this scenario is that the production rate is suppressed by a small initial abundance of dark matter and consequently creating the observed abundance requires much larger coupling values than for the usual freeze-in. We provide a concrete example model exhibiting such production mechanism and study it in detail, extending the standard formalism to include the evolution of dark matter temperature alongside its number density and discuss the importance of this improved treatment. Finally, we confront the relic density constraint with the limits and prospects for the dark matter indirect detection searches. We show that, even if it was never in full thermal equilibrium in the early Universe, dark matter could, nevertheless, have strong enough present-day annihilation cross section to lead to observable signals.


2021 ◽  
Vol 2021 (5) ◽  
Author(s):  
Lorenzo Calibbi ◽  
Francesco D’Eramo ◽  
Sam Junius ◽  
Laura Lopez-Honorez ◽  
Alberto Mariotti

Abstract Displaced vertices at colliders, arising from the production and decay of long-lived particles, probe dark matter candidates produced via freeze-in. If one assumes a standard cosmological history, these decays happen inside the detector only if the dark matter is very light because of the relic density constraint. Here, we argue how displaced events could very well point to freeze-in within a non-standard early universe history. Focusing on the cosmology of inflationary reheating, we explore the interplay between the reheating temperature and collider signatures for minimal freeze-in scenarios. Observing displaced events at the LHC would allow to set an upper bound on the reheating temperature and, in general, to gather indirect information on the early history of the universe.


2016 ◽  
Vol 25 (14) ◽  
pp. 1630027 ◽  
Author(s):  
John Ellis

The plethora of recent and forthcoming data on the cosmic microwave background (CMB) data are stimulating a new wave of inflationary model-building. Naturalness suggests that the appropriate framework for models of inflation is supersymmetry. This should be combined with gravity in a supergravity theory, whose specific no-scale version has much to commend it, e.g. its derivation from string theory and the flat directions in its effective potential. Simple no-scale supergravity models yield predictions similar to those of the Starobinsky [Formula: see text] model, though some string-motivated versions make alternative predictions. Data are beginning to provide interesting constraints on the rate of inflaton decay into Standard Model particles. In parallel, LHC and other data provide significant constraints on no-scale supergravity models, which suggest that some sparticles might have masses close to present experimental limits.


2000 ◽  
Vol 585 (1-2) ◽  
pp. 124-142 ◽  
Author(s):  
E. Accomando ◽  
R. Arnowitt ◽  
B. Dutta ◽  
Y. Santoso

2015 ◽  
Vol 2015 (03) ◽  
pp. 022-022 ◽  
Author(s):  
Giorgio Busoni ◽  
Andrea De Simone ◽  
Thomas Jacques ◽  
Enrico Morgante ◽  
Antonio Riotto
Keyword(s):  

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