Related papers: Long-Lived Neutralino NLSPs
A search for long-lived particles decaying to photons and weakly interacting particles, using proton-proton collision data at $\sqrt{s} =$ 13 TeV collected by the CMS experiment in 2016-2017 is presented. The data set corresponds to an…
We explore the potential of studying sterile neutrinos at a future high-energy muon collider, where these particles can generate small active neutrino masses via the seesaw mechanism and exhibit long-lived particle signatures. A Dirac…
This work investigates the possibility of a long-lived stop squark in supersymmetric models with the neutralino as the lightest supersymmetric particle (LSP). We study the implications of meta-stable stops on the sparticle mass spectra and…
A search for long-lived heavy neutrinos (N) in the decays of B mesons produced in proton-proton collisions at $\sqrt{s}$ = 13 TeV is presented. The data sample corresponds to an integrated luminosity of 41.6 fb$^{-1}$ collected in 2018 by…
A search is presented for long-lived particles decaying into an oppositely charged lepton pair, $\mu^{+}\mu^{-}$, $e^{+}e^{-}$, or $e^{\pm}\mu^{\mp}$, that form a vertex within the inner tracking system of the ATLAS detector at the Large…
A search is performed for heavy resonances decaying to two long-lived massive neutral particles, each decaying to leptons. The experimental signature is a distinctive topology consisting of a pair of oppositely charged leptons originating…
We investigate the LHC sensitivity to supersymmetric models with light higgsinos, small R-parity breaking and gravitino dark matter. The limits on decaying gravitino dark matter from gamma-ray searches with the Fermi-LAT put a lower bound…
New metastable massive particles with electric and colour charge are features of many theories beyond the Standard Model. A search is performed for long-lived gluino-based R-hadrons with the ATLAS detector at the LHC using a data sample…
We consider the possibility of Majorana neutrinos production at the Large Hadron Collider (LHC) by studying the $pp \rightarrow l_i^{+} l_j^{+} +2~jets$ ($l_j\equiv e ,\mu$) process which, due to leptonic number violation, is a clear…
A number of extensions of the Standard Model predict the existence of new light, weakly-coupled particles that couple to the visible sector through higher-dimensional operators containing one or two photons, suppressed by a high new physics…
It is shown that a decaying neutralino in a supergravity unified framework is a viable candidate for dark matter. Such a situation arises in the presence of a hidden sector with ultraweak couplings to the visible sector where the neutralino…
In the (M+1)SSM an additional gauge singlet Weyl spinor appears in the neutralino sector. For a large part of the parameter space this approximative eigenstate is the true LSP. Then most sparticle decays proceed via an additional cascade…
This paper describes a search for pairs of neutral, long-lived particles decaying in the ATLAS calorimeter. Long-lived particles occur in many extensions to the Standard Model and may elude searches for new promptly decaying particles. The…
Long-lived particles (LLPs) provide an unambiguous signal for physics beyond the Standard Model (BSM). They have a distinct detector signature, with decay lengths corresponding to lifetimes of around nanoseconds or longer. Lepton colliders…
The search strategy or the finding of new effects for heavy neutrinos often relies on their different decay channels to detectable particles. In particular in this work we study the decay of a Majorana neutrino with interactions obtained…
The four LEP collaborations have performed searches for supersymmetric particles in light gravitino scenarios, when neutralinos and sleptons are produced and may present measurable decay lengths. The highest energy data has been analysed…
We consider the dipole portal to sterile neutrinos, also called heavy neutral leptons (HNLs). The dipole interaction with the photon leads to HNL production in meson decays, as well as triggers the HNL decay into an active neutrino and a…
Within the framework of the $\mu\nu$SSM, a displaced dilepton signal is expected at the LHC from the decay of a tau left sneutrino as the lightest supersymmetric particle (LSP) with a mass in the range $45 - 100$ GeV. We compare the…
The experimental signatures for gauge mediated supersymmetry breaking are presented. The phenomenology associated with this class of models is distinctive since the gravitino is naturally the LSP. The next lightest supersymmetric particle…
We explore possible signatures for heavy neutrinos and neutral gauge boson, Z', in TeV scale B-L extension of the Standard Model (BLSM) with inverse seesaw mechanisms at the Large Hadron Collider. We show that due to new decay channels of…