51 research outputs found
Constraining self-interacting dark matter with scaling laws of observed halo surface densities
The observed surface densities of dark matter halos are known to follow a
simple scaling law, ranging from dwarf galaxies to galaxy clusters, with a weak
dependence on their virial mass. Here we point out that this can not only be
used to provide a method to determine the standard relation between halo mass
and concentration, but also to use large samples of objects in order to place
constraints on dark matter self-interactions that can be more robust than
constraints derived from individual objects. We demonstrate our method by
considering a sample of about 50 objects distributed across the whole halo mass
range, and by modelling the effect of self-interactions in a way similar to
what has been previously done in the literature. Using additional input from
simulations then results in a constraint on the self-interaction cross section
per unit dark matter mass of about cm/g. We
expect that these constraints can be significantly improved in the future, and
made more robust, by i) an improved modelling of the effect of
self-interactions, both theoretical and by comparison with simulations, ii)
taking into account a larger sample of objects and iii) by reducing the
currently still relatively large uncertainties that we conservatively assign to
the surface densities of individual objects. The latter can be achieved in
particular by using kinematic observations to directly constrain the average
halo mass inside a given radius, rather than fitting the data to a pre-selected
profile and then reconstruct the mass. For a velocity-independent
cross-section, our current result is formally already somewhat smaller than the
range cm/g that has been invoked to explain potential
inconsistencies between small-scale observations and expectations in the
standard collisionless cold dark matter paradigm.Comment: 29 pages with jcappub.sty, 10 figures. Significantly improved
discussion of method and limits. Version submitted to JCA
Sensitivity of the intensity frontier experiments for neutrino and scalar portals: analytic estimates
In recent years, a number of intensity-frontier experiments have been
proposed to search for feebly interacting particles with a mass in the GeV
range. We show analytically how the characteristic shape of the sensitivity
regions of such experiments - upper and lower boundaries of the probed region,
the maximal mass reach - depends on the parameters of the experiments, taking
the SHiP and the MATHUSLA experiments as an example. We find a good agreement
of our estimates with the results of the Monte Carlo simulations.Comment: Journal versio
Probing new physics with displaced vertices: muon tracker at CMS
Long-lived particles can manifest themselves at the LHC via "displaced
vertices" - several charged tracks originating from a position separated from
the proton interaction point by a macroscopic distance. Here we demonstrate a
potential of the muon trackers at the CMS experiment for displaced vertex
searches. We use heavy neutral leptons and Chern-Simons portal as two examples
of long-lived particles for which the CMS muon tracker can provide essential
information about their properties.Comment: Journal versio
Sensitivity of the FACET experiment to Heavy Neutral Leptons and Dark Scalars
We analyze the potential of the recently proposed experiment FACET (Forward-Aperture CMS ExTension) to search for new physics. As an example, we consider the models of Higgs-like scalars with cubic and quartic interactions and Heavy Neutral Leptons. We compare the sensitivity of FACET with that of other proposed “intensity frontier” experiments, including FASER2, SHiP, etc. and demonstrate that FACET could probe an interesting parameter space between the current constraints and the potential reach of the above mentioned proposals
Phenomenology of GeV-scale scalar portal
We review and revise the phenomenology of the scalar portal -- a new scalar
particle with the mass in GeV range that mixes with the Higgs boson. In
particular, we consider production channels and and show that their contribution is significant. We extend the
previous analysis by comparing the production of scalars from decays of mesons,
of the Higgs bosons and direct production via proton bremsstrahlung, deep
inelastic scattering and coherent scattering on nuclei. Relative efficiency of
the production channels depends on the energy of the beam and we consider the
energies of DUNE, SHiP and LHC-based experiments. We present our results in the
form directly suitable for calculations of experimental sensitivities.Comment: Journal versio
Phenomenology of GeV-scale Heavy Neutral Leptons
We review and revise phenomenology of the GeV-scale heavy neutral leptons
(HNLs). We extend the previous analyses by including more channels of HNLs
production and decay and provide with more refined treatment, including QCD
corrections for the HNLs of masses GeV. We summarize the
relevance of individual production and decay channels for different masses,
resolving a few discrepancies in the literature. Our final results are directly
suitable for sensitivity studies of particle physics experiments (ranging from
proton beam-dump to the LHC) aiming at searches for heavy neutral leptons.Comment: journal versio
Connection between diphoton and triboson channels in new physics searches
Diphoton channel provides a clean signature in searches for new physics. In
this paper, we discuss a connection between the diphoton channel
() and triboson channels (, ,
) imposed by the symmetry of the Standard
Model (SM) in certain classes of models. To illustrate this idea we choose a
simple model that has all these channels. In this model, the same physics can
give rise to MET instead of and 2 bosons plus missing
energy instead of 3-boson channels. We analyze existing constraints and
previous searches and show that channels and especially
MET have a potential to discover new physics at the LHC
Sensitivities to feebly interacting particles: public and unified calculations
The idea that new physics could take the form of feebly interacting particles (FIPs) - particles with a mass below the electroweak scale, but which may have evaded detection due to their tiny couplings or very long lifetime - has gained a lot of traction in the last decade, and numerous experiments have been proposed to search for such particles. It is important, and now very timely, to consistently compare the potential of these experiments for exploring the parameter space of various well-motivated FIPs. The present paper addresses this pressing issue by presenting an open-source tool to estimate the sensitivity of many experiments - located at Fermilab or at the CERN\u27s SPS, LHC, and FCC-hh - to various models of FIPs in a unified way: the Mathematica-based code SensCalc
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