LHC experiments for long-lived particles of the dark sector

Abstract

webific.ific.uv.es/web Dark matter scenarios are being tested at the LHC in the general-purpose experiments through promptly decaying states. In parallel, new dedicated detectors have been proposed for the LHC to probe dark matter portal theories predicting long-lived particles that decay away from the interaction point: MoEDAL-MAPP, MoEDAL-MALL, FASER, SND@LHC, CODEX-b, MATHUSLA, AL3X, ANUBIS, FACET, milliQan, FORMOSA. In addition, the SHiP beam-dump experiment is planned to operate with the SPS beam to extend the discovery reach for such particles. The detector design and expected physics sensitivity of these experiments will be presented with emphasis on scenarios explaining the nature of dark matter.

Discovery prospects for long-lived multiply charged particles at the LHC

“…As can be seen, the effective cross section increases significantly for larger Q. This is because the photon-fusion process is very important for colourless particles, and its production rate grows with Q 4 .…”

“…Since the Z -boson is much heavier than the proton, the parton distribution functions (PDFs) used for LHC analyses do not include the Z -boson as a parton. 4 At LHC energies, the Z -boson initiated processes should be better understood as the Z /γ fusion processes, qq → qqφ +Q φ −Q or qq → qqψ +Q ψ −Q . One of such diagrams is depicted in Fig.…”

“…To evaluate the significance of the Z -boson contribution to the Z /γ fusion process with respect to the γ γ fusion, we compare the two cross sections computed with MadGraph 5 by the following commands: σ inc : generate u u > u u phiQ 4 Electroweak bosons (Z , W ± and h) should be included in the PDFs for future high energy hadron colliders with √ s ∼ 100 TeV. See e.g.…”

“…As conventional searches kept on showing no deviation from the SM predictions, the interest of the experimental -and theoretical -community started shifting towards less orthodox final states, such as those by long-lived particles a e-mail: r.maselek@uw.edu.pl (corresponding author) (LLPs) [2][3][4]. In theory, long lifetimes may be due to a symmetry (leading to stable particles), narrow mass splittings, small couplings, or a heavy mediator.…”