Bound-state effects on dark matter coannihilation: Pushing the boundaries of conversion-driven freeze-out

Abstract

Bound-state formation can have a large impact on the dynamics of dark matter freeze-out in the early Universe, in particular for colored coannihilators. We present a general formalism to include an arbitrary number of excited bound states in terms of an effective annihilation cross section, taking bound-state formation, decay and transitions into account, and derive analytic approximations in the limiting cases of no or efficient transitions. Furthermore, we provide explicit expressions for radiative bound-state formation rates for states with arbitrary principal and angular quantum numbers $n,\ell$ for a mediator in the fundamental representation of $SU(3{)}_c$, as well as electromagnetic transition rates among them in the Coulomb approximation. We then assess the impact of bound states within a model with Majorana dark matter and a colored scalar $t$-channel mediator. We consider the regime of coannihilation as well as conversion-driven freeze-out (or coscattering), where the relic abundance is set by the freeze-out of conversion processes. We find that the region in parameter space where the latter occurs is considerably enhanced into the multi-TeV regime. For conversion-driven freeze-out, dark matter is very weakly coupled, evading direct and indirect detection constraints but leading to prominent signatures of long-lived particles that provide great prospects to be probed by dedicated searches at the upcoming LHC runs.

arXiv commentv3: Minor presentational improvements, left panel of Fig. 2 and Tab. 1 updated

References in corpus (44)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• Neutralino Relic Density including Coannihilations
• micrOMEGAs5.0 : freeze-in
• Dark matter direct-detection experiments
• Calculations of Neutralino-Stau Coannihilation Channels and the Cosmologically Relevant Region of MSSM Parameter Space
• NLO Production and Decay of Quarkonium
• A review of indirect searches for particle dark matter
• Review of LHC Dark Matter Searches
• Light Scalar Top Quarks and Supersymmetric Dark Matter
• Calculations of Neutralino-Stop Coannihilation in the CMSSM
• DarkSUSY 6 : An Advanced Tool to Compute Dark Matter Properties Numerically
• MadDM v.3.0: a Comprehensive Tool for Dark Matter Studies
• NNLL-fast: predictions for coloured supersymmetric particle production at the LHC with threshold and Coulomb resummation
• Cosmological Implications of Dark Matter Bound States
• Search for long-lived charginos based on a disappearing-track signature in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Search for long-lived, massive particles in events with displaced vertices and missing transverse momentum in $\sqrt{s}$ = 13 TeV $pp$ collisions with the ATLAS detector
• Thermal width and gluo-dissociation of quarkonium in pNRQCD
• Search for heavy charged long-lived particles in the ATLAS detector in 36.1 fb${}^{-1}$ of proton-proton collision data at $\sqrt{s}=13$ TeV
• A Fourth Exception in the Calculation of Relic Abundances
• Dark-matter bound states from Feynman diagrams
• Coannihilation without chemical equilibrium
• Signatures of Majorana dark matter with t-channel mediators
• Gluino Coannihilation Revisited
• Anatomy of Coannihilation with a Scalar Top Partner
• Quarkonium inside Quark-Gluon Plasma: Diffusion, Dissociation, Recombination and Energy Loss
• Coupled Boltzmann Transport Equations of Heavy Quarks and Quarkonia in Quark-Gluon Plasma
• Top-philic dark matter within and beyond the WIMP paradigm
• Capture and Decay of Electroweak WIMPonium
• Effects of QCD bound states on dark matter relic abundance
• Radiative bound-state formation in unbroken perturbative non-Abelian theories and implications for dark matter
• Thermal dark matter co-annihilating with a strongly interacting scalar
• Non-Abelian Electric Field Correlator at NLO for Dark Matter Relic Abundance and Quarkonium Transport
• Coloured coannihilations: Dark matter phenomenology meets non-relativistic EFTs
• A feeble window on leptophilic dark matter
• A universal framework for t-channel dark matter models
• Leptoquark manoeuvres in the dark: a simultaneous solution of the dark matter problem and the $R_{D^{(\ast )}}$ anomalies
• Dark Matter bound-state formation at higher order: a non-equilibrium quantum field theory approach
• Exchange driven freeze out of dark matter
• Search for heavy charged long-lived particles in proton-proton collisions at $\sqrt{s}=13$ TeV using an ionisation measurement with the ATLAS detector
• Forbidden Dark Matter at the Weak Scale via the Top Portal
• Closing in on $t$-channel simplified dark matter models
• Radiative corrections to stoponium annihilation decays
• Coscattering in next-to-minimal dark matter and split supersymmetry
• Soft displaced leptons at the LHC

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• Bound-state formation, dissociation and decays of darkonium with potential non-relativistic Yukawa theory for scalar and pseudoscalar mediators
• Conversion-Driven Leptogenesis: A Testable Theory of Dark Matter and Baryogenesis at the Electroweak Scale
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• Anatomy of singlet-doublet dark matter relic: annihilation, co-annihilation, co-scattering, and freeze-in
• Non-perturbative effects for dark sectors with QCD portals
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• t-channel dark matter at the LHC -- a whitepaper
• Flavoured Majorana Dark Matter then and now: From freeze-out scenarios to LHC signatures
• The role of unitarisation on dark-matter freeze-out via metastable bound states
• Illuminating Scalar Dark Matter Co-Scattering in EFT with Monophoton Signatures
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• Effective Field Theories for Dark Matter Pairs in the Early Universe
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