We identify potentially the world's most sensitive location to search for millicharged particles in the 10 MeV to 100 GeV mass range: the forward region at the LHC. We propose constructing a scintillator-based experiment, FORward MicrOcharge SeArch (FORMOSA) in this location, and estimate the corresponding sensitivity projection. We show that FORMOSA can discover millicharged particles in a...
We have investigated the search sensitivity to long lived light neutralinos, with masses below a few GeV down to 10s of MeV, at various forward detectors. The can be produced at the LHC via rare decays of standard mesons or via rare Z-boson decays. The neutralinos decay to a lighter meson plus a charged lepton, which can be observed. We have studied a large set of proposed experiments: ANUBIS;...
Charged current neutrino interactions have been extensively studied in the context of various experiments, including FASER$\nu$. The presence of a charged lepton in the final state allows for easy identification of candidate signal events and incoming beam energy reconstruction. Neutral current neutrino interaction on the other hand have a neutrino in the final state. This imposes two...
Tau neutrino is the least known particle of the Standard Model, first discovered by DONUT experiment in 2001. In DONUT, using tau neutrino interaction cross section was measured with large systematical (~50%) and statistical (~30%) errors. The main source of systematical error is due to a poor knowledge of the tau neutrino flux from Ds decays. The DsTau experiment at CERN-SPS has been...
In this talk, I will present some additional physics potential of FORMOSA, that not only provides leading sensitivity to MCPs but also is extremely sensitive to other forms of exotica beyond the standard model (BSM), such as heavy neutrinos and DM with a large electric dipole moment (EDM). Furthermore, we expect a sizable number of interactions of TeV-energy neutrinos in FORMOSA, providing...
We consider strategies for using new datasets to probe
scenarios in which light right-handed SM fermions couple
to a new gauge group, $U(1)_{T3R}$. This scenario
provides a natural explanation for the light flavor
sector scale, and a motivation for sub-GeV dark matter.
There is parameter space which is currently allowed, but
we find that much of it can be probed...
We calculate the prompt muon and tau neutrino (and antineutrino) number of events in the far forward region at the LHC. In a region as such, the heavy quark decay dominates the tau neutrino production. The hadronic charm and bottom hadron production cross section is evaluated at the next-to-leading order in perturbative QCD. The intrinsic transverse momentum of the initial partons becomes...
FASER is one of the promising experiments which search for long-lived particles in beyond standard models.
In this paper, we focus on dark photon associating with an additional U(1) gauge symmetry, and also a scalar boson
breaking this U(1) gauge symmetry.
We study the sensitivity to the dark photon originated from U(1)-breaking scalar decays.
We find that sizable number of the dark...
One of the primary aims of the Forward Physics Facility (FPF) would be to search for highly-displaced decays of light and long-lived particles (LLPs) produced in proton-proton collisions at the LHC. These searches are, however, limited to new particles with decay lengths similar to or larger than the baseline of the FPF. We will discuss how this basic constraint can be overcome in models that...
In the very forward region of the LHC, a number of tau neutrinos can be produced mostly from the $D_s^\pm$ decay. For an integrated luminosity of 3000 $\rm fb^{-1}$ at the HL-LHC, thousands of charged current tau neutrino events are expected in a detector of $\rm m^3$ size. It will allow the study of the mixing between sterile neutrinos and tau neutrinos with the fact that the possible...
We propose simple freeze-in models where the observed dark matter abundance is explained via the decay of an electrically charged and/or coloured parent particle into Feebly Interacting Massive Particles (FIMP). The parent particle is long-lived and yields a wide variety of LHC signatures depending on its lifetime and quantum numbers. We assess the current constraints and future high...
The FASER$\nu$ detector is a newly proposed detector whose main mission is to detect neutrino flux from the collision of the proton beams at the ATLAS Interaction Point (IP) during run III of the LHC in 2021-2023. We show that this detector can also test certain beyond standard model scenarios, especially the ones in which the neutrino interaction with matter fields can produce new unstable...
In the context of a well-motivated gauged U(1) extension of the Standard Model, we introduce a non-thermal dark matter whose interaction is too weak to allow it to be in thermal equilibrium with the Standard Model particles, and its relic density is determined by the freeze-in mechanism through a light mediator that is the extra U(1) gauge boson. We discuss a complementarity between the...
We study the prospects of a displaced-vertex search of sterile neutrinos at the Large Hadron Collider (LHC) in the framework of the neutrino-extended Standard Model Effective Field Theory. The production and decay of sterile neutrinos can proceed via the standard active-sterile neutrino mixing in the weak current, as well as via higher-dimensional operators arising from potentially new,...
We consider the nonminimal quartic inflation in a classically conformal U(1)$_X$ extended SM. We show that if the inflaton mass and its mixing angle with the SM Higgs field lie in a suitable range, the FASER experiment can search for the inflaton at the High Luminosity (HL)-LHC. Also because of the classical conformal invariance, the inflationary predictions and the LHC search for the U(1)$_X$...
We give a short review of recent Mueller-Navelet jets studies at the LHC and we propose new related observables to be used as probes of the BFKL dynamics.
In this talk I will discuss the connection of different neutrino mass models with long-lived particles (LLPs). We will also discuss the prospects of the LHC and several recent experimental proposals to search for these LLPs.
