相关论文: Constraining electroweak and strongly charged long…
We present Self-Destructing Dark Matter (SDDM), a new class of dark matter models which are detectable in large neutrino detectors. In this class of models, a component of dark matter can transition from a long-lived state to a short-lived…
Although the LHC experiments have searched for and excluded many proposed new particles up to masses close to 1 TeV, there are many scenarios that are difficult to address at a hadron collider. This talk will review a number of these…
We consider a dark sector model containing stable fermions charged under an unbroken $U(1)$ gauge interaction, with a massless dark photon as force carrier, and interacting with ordinary matter via scalar messengers. We study its early…
In recent years, the sensitivity of opto-mechanical force sensors has improved leading to increased interest in using these devices as particle detectors. In this study we consider scenarios where dark matter with mass close to the Planck…
New physics close to the electroweak scale is well motivated by a number of theoretical arguments. However, colliders, most notably the Large Hadron Collider (LHC), have failed to deliver evidence for physics beyond the Standard Model. One…
A search is presented for free heavy long-lived fractionally charged particles produced in pp collisions at sqrt(s) = 7 TeV. The data sample was recorded by the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0…
Most data gathered from high energy experiments at colliders are analyzed assuming that particles stable enough to not decay in the detector volume, and able to interact strongly or electromagnetically, must be electrons, muons, protons,…
These four lectures constitute a gentle introduction to what may lie beyond the standard model of quarks and leptons interacting through $SU(3)_c \otimes SU(2)_L \otimes U(1)_Y$ gauge bosons, prepared for an audience of graduate students in…
Heavy long-lived multi-charged leptons (MCLs) are predicted by various new physics models. These hypothetical MCLs can form bound states, due to their high electric charges and long life times. In this work, we propose a novel strategy of…
We search for new long-lived particles which decay to Z bosons by looking for Z->e+e- decays with displaced vertices. We find no evidence for parent particles of the Z with long lifetimes in 90 pb-1 of data from the CDF experiment at…
A model for composite elementary Standard Model (SM) particles based upon magnetically bound vorton pairs, briefly introduced here, predicts the existence of a complete family of magnetically charged particles, as well as their neutral…
Recently, the vector-like leptons (VLLs) as a simple extension to the standard model (SM) have attracted widespread attention both in theory and experiments. The present collider searches mainly focus on the studies of their prompt decays,…
The Standard Model (SM) fails to explain many problems (neutrino masses, dark matter, and matter-antimatter asymmetry, among others) that may be resolved with new particles beyond the Standard model (BSM). The fact that such new particles…
The nonbaryonic dark matter of the Universe is assumed to consist of new stable forms of matter. Their stability reflects symmetry of micro world and particle candidates for cosmological dark matter are the lightest particles that bear new…
A variety of new physics models predict heavy resonances that decay to multiple hadronic jets. These models include axigluons, colorons, diquarks, excited quarks, Randall-Sundrum gravitons, string resonances, and Z' models, among others.…
All extensions of the standard model that generate Majorana neutrino masses at the electro-weak scale introduce some "heavy" mediators, either fermions and/or scalars, weakly coupled to leptons. Here, by "heavy" we understand implicitly the…
We explore the physics potential of using precision timing information at the LHC in searches for long-lived particles (LLPs). In comparison with the light Standard Model particles, the decay products of massive LLPs arrive at detectors…
A search for long-lived particles (LLPs) using 140 fb$^{-1}$ of $pp$ collision data with $\sqrt{s} = 13$ TeV recorded by the ATLAS experiment at the LHC is presented. The search targets LLPs with masses between $5$ and $55$ GeV that decay…
We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in…
In contrast to the decay products ensuing from a fast moving particle which are collimated along the original direction of the parent, those from a slow moving particle are distributed over a wide region. In the context of searches for…