Colliders as a simultaneous probe of supersymmetric dark matter and Terascale cosmology

Abstract

Terascale supersymmetry has the potential to provide a natural explanation of the dominant dark matter component of the standard ΛCDM cosmology. However once we impose the constraints on minimal supersymmetry parameters from current particle physics data, a satisfactory dark matter abundance is no longer prima facie natural. This Neutralino Tuning Problem could be a hint of nonstandard cosmology during and/or after the Terascale era. To quantify this possibility, we introduce an alternative cosmological benchmark based upon a simple model of quintessential inflation. This benchmark has no free parameters, so for a given supersymmetry model it allows an unambiguous prediction of the dark matter relic density. As a example, we scan over the parameter space of the CMSSM, comparing the neutralino relic density predictions with the bounds from WMAP. We find that the WMAP-allowed regions of the CMSSM are an order of magnitude larger if we use the alternative cosmological benchmark, as opposed to ΛCDM. Initial results from the CERN Large Hadron Collider will distinguish between the two allowed regions.

Quintessence, inflation and baryogenesis from a single pseudo-Nambu-Goldstone boson

“…If dark matter is predominately composed of thermally produced WIMPs, this prediction can be tested by combining collider data with signals from direct and indirect WIMP searches [8], [21]- [25].…”

“…The Slinky model of quintessential inflation introduced in [6]- [8] is a PNGB quintessence model of the general class just described, but with some special features. It does not require tuned initial conditions; in particular the initial value ofθ is of order H. It is the simplest model with a periodic equation of state parameter for quintessence.…”

Connecting LHC, ILC, and quintessence

“…the standard scenario and the kination domination scenario. The anticipated collider data will allow us to probe in the laboratory a new era in cosmological history, which may lead to significant deviations from the standard cosmological picture [49][50][51][52].…”

Inflationary cosmology connecting dark energy and dark matter

“…[14,15,16,17,18]), but we treat the reheating more precisely and derive new predictions in the context of kination-dominated quintessence models relevant for dark matter. The work [10] considers the connection between dark energy and dark matter, but it differs from the present treatment in that their scenario is model specific and has multiple inflationary phases. In addition to the prediction that the relic abundance inferred from collider measurements can measurably disagree with the cosmologically inferred dark matter relic abundance (in the context of a thermal freeze-out scenario), many experimentally accessible cosmological predictions can be made by embedding the kination domination scenario in inflationary models.…”

“…This scenario is extremely difficult (if not impossible) to test directly in collider experiments, since quintessence models generically require the quintessence field to have gravitationally suppressed interactions with the fields of the Standard Model (SM).However, if the dark energy is in the form of quintessence, the presence of the quintessence field can modify the cosmological evolution and lead to significant departures from standard cosmology. A striking example is the possible interconnection of dark matter and dark energy within quintessence scenarios [6,7,8,9,10]. As first pointed out by Salati [6], the freeze-out of thermal relics can be strongly enhanced in scenarios in which the energy density is dominated by the kinetic energy of the quintessence field (kination domination) during the time of freeze-out, but dilutes away by the time of big bang nucleosynthesis (BBN).…”