SearcharxivSearch

arXiv subjects

Robert Craig Group

Publications and source records attributed to Robert Craig Group.

8 recordsLinked to original sources

Measurement of the LCLS-II dark current using the LDMX Trigger Scintillator Prototype

The Light Dark Matter eXperiment (LDMX) is a proposed fixed-target missing momentum search for sub-GeV thermal relic dark matter. LDMX aims to probe thermal dark matter targets with 1016 electrons on target. Such an approach requires a high-repetition rate, low-current beam, with an average of one electron on target per event. These requirements are well-suited to the DArk Sector Experiments at LCLS-II (DASEL) facility, which will take advantage of the unused RF buckets between LCLS-II bunches to produce a well-defined low-current beam with a 26.9 ns bunch spacing. This document describes the results of a measurement of dark current in the Sector 30 transfer line (S30XL) of the LCLS-II beam, using a prototype of the LDMX trigger scintillator (TS) subsystem.

hep-ex

Mass testing of SiPMs for the CMVD at IICHEP

A Cosmic Muon Veto Detector (CMVD) is being built around the mini-Iron Calorimeter (mini-ICAL) detector at the transit campus of the India based Neutrino Observatory, Madurai. The CMV detector will be made using extruded plastic scintillators with embedded wavelength shifting (WLS) fibres which propagate re-emitted photons of longer wavelengths to silicon photo-multipliers (SiPMs). The SiPMs detect these scintillation photons, producing electronic signals. The design goal for the cosmic muon veto efficiency of the CMV is $>$99.99\% and fake veto rate less than 10$^{-5}$. A testing system was developed, using an LED driver, to measure the noise rate and gain of each SiPM, and thus determine its overvoltage ($V_{ov}$). This paper describes the test results and the analysed characteristics of about 3.5k SiPMs.

physics.ins-det

Qualification study of SiPMs on a large scale for the CMVD Experiment

A Cosmic Muon Veto (CMV) detector using extruded plastic scintillators is being designed around the mini-Iron Calorimeter (mini-ICAL) detector at the transit campus of the India based Neutrino Observatory, Madurai for the feasibility study of shallow depth underground experiments. The scintillation signals that are produced in the plastic due to muon trajectories are absorbed by wavelength shifting (WLS) fibres. The WLS fibres re-emit photons of longer wavelengths and propagate those to silicon photo-multipliers (SiPMs). The SiPMs detect these photons, producing electronic signals. The CMV detector will use more than 700 scintillators to cover the mini-ICAL detector and will require around 3000 SiPMs. The design goal for the cosmic muon veto efficiency of the CMV is >99.99%. Hence, every SiPM used in the detector needs to be tested and characterised to satisfy the design goal of CMV. A mass testing system was developed for the measurement of gain and choice of the overvoltage ($V_{ov}$) of each SiPMs using an LED driver. The $V_{ov}$ is obtained by studying the noise rate, the gain of the SiPM. This paper describes the experimental setup used to test the SiPMs characteristics along with detailed studies of those characteristics as a function of temperature.

physics.ins-det

Characterization of Silicon-Photomultipliers for a Cosmic Muon Veto detector

A Cosmic Muon Veto (CMV) detector using extruded scintillators is being designed around the mini-Iron Calorimeter detector at the transit campus of the India-based Neutrino Observatory at Madurai for measuring its efficiency at shallow depth underground experiments. The scintillation signal is transmitted through a Wavelength Shifting (WLS) fibre and readout by Hamamatsu Silicon-Photomultipliers (SiPMs). A Light Emitting Diode (LED) system is included on the front-end readout for in-situ calibration of the gain of each SiPM. A characterization system was developed for the measurement of gain and choice of the overvoltage (Vov) of SiPMs using LED as well as a cosmic muon telescope. The Vov is obtained by studying the noise rate, the gain of the SiPM, and the muon detection efficiency. In case of any malfunction of the LED system during the operation, the SiPM can also be calibrated with the noise data as well as using radioactive sources. This paper describes the basic characteristics of the SiPM and the comparison of the calibration results using all three methods, as well as the Vov of the SiPMs and muon selection criteria for the veto detector.

hep-ex

Design considerations for the cosmic-ray-veto system of the Mu2e experiment at Fermilab

Since the discovery of the muon, particle physicists have carried out a series of experiments aimed at measuring flavor violation in charged-lepton interactions. To date, no such violation has been observed. The Mu2e experiment at Fermilab will search for the charged lepton flavor violating process of coherent muon-to-electron conversion in the presence of a nucleus with a sensitivity four orders of magnitude beyond current limits. The experiment will have a single event sensitivity of about $2.5\times10^{-17}$ while limiting the total background to less than 0.5 events. One potential background is due to cosmic-ray muons producing an electron that is indistinguishable from signal within the Mu2e apparatus. The cosmic-ray-veto system of the Mu2e experiment is tasked with vetoing cosmic-ray-induced backgrounds with high efficiency without inducing significant dead time and while operating in a high-intensity environment. In this note the challenges related to the high-radiation environment that influence the design of the cosmic-ray-veto system will be discussed.

physics.ins-det

Higgs Boson Searches at CDF

Results are presented on searches for standard model and non-standard model production of a Higgs boson in pbar-p collisions at sqrt{s}= 1.96 TeV with the CDF II detector at the Fermilab Tevatron. Using data corresponding to 2-3.6 1/fb of integrated luminosity, searches are performed in a number of different production and decay modes. No excess in data above that expected from backgrounds is observed; therefore, we set upper limits on the production cross section times branching fraction as a function of the Higgs boson mass.

hep-ex

Recent QCD Studies at the Tevatron

Since the beginning of Run II at the Fermilab Tevatron, the QCD physics groups of the CDF and D0 experiments have worked to reach unprecedented levels of precision for many QCD observables. Thanks to the large dataset - over 3 fb^-1 of integrated luminosity recorded by each experiment - many important new measurements have recently been made public and will be summarized in this paper.

hep-ex