arXiv subjects

Joseph Reichert

Publications and source records attributed to Joseph Reichert.

4 recordsLinked to original sources

arXiv2026

Signals of New Resonances from Di-Lepton Non-Universality in the Bottomonium Mass Region at the Large Hadron Collider

Universality classes of new physics models featuring narrow boson resonances produced through strongly interacting initial states in proton-proton collisions and with enhanced decays to di-tau final states are classified. Spin-zero scalar or pseudoscalar bosons with chirality-violating fermion couplings can induce potentially significant di-lepton non-universality in the bottomonium mass region, with up to many hundreds of nanobarns of direct production total cross section in proton-proton collisions at the Large Hadron Collider. Conversely, mass suppressed chirality-violating couplings of spin-zero bosons to di-electrons maintain di-lepton universality to a high degree in the same mass region at electron-positron colliders. Simultaneous measurement and comparison of integrated resonant prompt di-electron, di-muon, and di-tau mass spectra at the Large Hadron Collider in the bottomonium mass region could be sensitive to the existence of new boson resonances with enhanced di-tau decays, or likewise bottomonium states with non-Standard Model enhanced di-tau decay modes.

hep-ph↗

arXiv2023

Direct Searches at CMS

Several of the CMS experiment's latest results on direct searches for new physics are presented. In particular, an emphasis is made to highlight the new models, unexplored final states, and innovative tools for discovery that these searches focus on.

hep-ex↗

arXiv2022

Strange quark as a probe for new physics in the Higgs sector

This paper describes a novel algorithm for tagging jets originating from the hadronisation of strange quarks (strange-tagging) with the future International Large Detector (ILD) at the International Linear Collider (ILC). It also presents the first application of such a strange-tagger to a Higgs to strange ($h \rightarrow s\bar{s}$) analysis with the $P(e^-,e^+) = (-80\%,+30\%)$ polarisation scenario, corresponding to 900 fb$^{-1}$ of the initial proposed 2000 fb$^{-1}$ of data which will be collected by ILD during its first 10 years of data taking at $\sqrt{s} = 250$ GeV. Upper limits on the Standard Model Higgs-strange coupling strength modifier, $κ_s$, are derived at the 95% confidence level to be 7.14. The paper includes as well a preliminary study of a Ring Imaging Cherenkov (RICH) system capable of discriminating between kaons and pions at high momenta (up to 25 GeV), and thus enhancing strange-tagging performance at future Higgs factory detectors.

hep-ex↗

arXiv2015

The Heavy Photon Search Test Detector

The Heavy Photon Search (HPS), an experiment to search for a hidden sector photon in fixed target electroproduction, is preparing for installation at the Thomas Jefferson National Accelerator Facility (JLab) in the Fall of 2014. As the first stage of this project, the HPS Test Run apparatus was constructed and operated in 2012 to demonstrate the experiment's technical feasibility and to confirm that the trigger rates and occupancies are as expected. This paper describes the HPS Test Run apparatus and readout electronics and its performance. In this setting, a heavy photon can be identified as a narrow peak in the e$^+$e$^-$ invariant mass spectrum, above the trident background or as a narrow invariant mass peak with a decay vertex displaced from the production target, so charged particle tracking and vertexing are needed for its detection. In the HPS Test Run, charged particles are measured with a compact forward silicon microstrip tracker inside a dipole magnet. Electromagnetic showers are detected in a PbW0$_{4}$ crystal calorimeter situated behind the magnet, and are used to trigger the experiment and identify electrons and positrons. Both detectors are placed close to the beam line and split top-bottom. This arrangement provides sensitivity to low-mass heavy photons, allows clear passage of the unscattered beam, and avoids the spray of degraded electrons coming from the target. The discrimination between prompt and displaced e$^+$e$^-$ pairs requires the first layer of silicon sensors be placed only 10~cm downstream of the target. The expected signal is small, and the trident background huge, so the experiment requires very large statistics. Accordingly, the HPS Test Run utilizes high-rate readout and data acquisition electronics and a fast trigger to exploit the essentially 100% duty cycle of the CEBAF accelerator at JLab.

physics.ins-det↗