Origins of hidden sector dark matter II: collider physics

Self Cite

126

We present a systematic cosmological study of a universe in which the visible sector is coupled, albeit very weakly, to a hidden sector comprised of its own set of particles and interactions. Assuming that dark matter (DM) resides in the hidden sector and is charged under a stabilizing symmetry shared by both sectors, we determine all possible origins of weak-scale DM allowed within this broad framework. We show that DM can arise only through a handful of mechanisms, lending particular focus to Freeze-Out and Decay and Freeze-In, as well as their variations involving late time re-annihilations of DM and DM particle anti-particle asymmetries. Much like standard Freeze-Out, where the abundance of DM depends only on the annihilation cross-section of the DM particle, these mechanisms depend only on a very small subset of physical parameters, many of which may be measured directly at the LHC. In particular, we show that each DM production mechanism is associated with a distinctive window in lifetimes and cross-sections for particles which may be produced in the near future. We evaluate prospects for employing the LHC to definitively reconstruct the origin of DM in a companion paper.

Section: Jhep03(2011)042mentioning

confidence: 99%

“…This offers the exciting prospect that the origin of DM might be successfully reconstructed from collider physics in this enormous and theoretically motivated class of theories. We consider the details of such an endeavor in a companion paper [9].…”

Section: Jhep03(2011)042mentioning

confidence: 99%

Origins of hidden sector dark matter I: cosmology

Cheung

Elor

Hall

et al. 2011

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126

“…This is intriguing as although these couplings are small it is not infeasible that they might be probed by experiments, see [39][40][41][42][43][44] for relevant remarks. Further, supplementing the mediator sector (containing φ) with additional states, which introduce new sources of CP-violation, could provide an interesting variant as it may be possible to enhance the size of .…”

Section: Jhep10(2014)190mentioning

confidence: 99%

“…In models of DM freeze-in [39][40][41][42][43][44] it is generally assumed that the hidden and visible sectors are both separately in thermal equilibrium at different temperatures, with the hidden sector being cooler. Correspondingly, the DM states χ initially have a depleted number density relative to the visible sector states.…”

Section: Introductionmentioning

confidence: 99%

Towards cogenesis via Asymmetric Freeze-In: the χ who came-in from the cold

Unwin

2014

In models of freeze-in the dark matter (DM) is decoupled from the visible sector and initially has a depleted number density. The hidden and visible sectors are connected only via a feeble portal interaction by which DM can be produced. Asymmetric freeze-in (AFI) combines this scenario with ideas from asymmetric DM and provides a potential cogenesis mechanism. However, it has been argued that existing AFI models do not produce suitably large particle asymmetries due to cancellations which arises because the mediator state remains in thermal equilibrium. We examine AFI via an out-of-equilibrium mediator and using a simple scalar model show that in this case sizeable asymmetries may be generated.

“…As such, both theoretical and experimental programs have moved beyond the WIMP paradigm. On the theoretical side, explorations of alternative dark matter candidates and production mechanisms have motivated dark matter masses below a GeV [4][5][6][7][8][9][10][11][12][13][14][15][16]. On the experimental side, progress has been made on the size frontier -where ton-scale experiments are needed to search for signals with rates consistent with current bounds.…”

Section: Introductionmentioning

confidence: 99%

Absorption of fermionic dark matter by nuclear targets

Dror

Elor

McGehee

2020

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Absorption of fermionic dark matter leads to a range of distinct and novel signatures at dark matter direct detection and neutrino experiments. We study the possible signals from fermionic absorption by nuclear targets, which we divide into two classes of four Fermi operators: neutral and charged current. In the neutral current signal, dark matter is absorbed by a target nucleus and a neutrino is emitted. This results in a characteristically different nuclear recoil energy spectrum from that of elastic scattering. The charged current channel leads to induced β decays in isotopes which are stable in vacuum as well as shifts of the kinematic endpoint of β spectra in unstable isotopes. To confirm the possibility of observing these signals in light of other constraints, we introduce UV completions of example higher dimensional operators that lead to fermionic absorption signals and study their phenomenology. Most prominently, dark matter which exhibits fermionic absorption signals is necessarily unstable leading to stringent bounds from indirect detection searches. Nevertheless, we find a large viable parameter space in which dark matter is sufficiently long lived and detectable in current and future experiments.