120 research outputs found
Electron Cloud Measurements in Fermilab Booster
Fermilab Booster synchrotron requires an intensity upgrade from 4.5x1012 to
6.5x1012 protons per pulse as a part of Fermilab's Proton Improvement Plan-II
(PIP-II). One of the factors which may limit the high-intensity performance is
the fast transverse instabilities caused by electron cloud effects. According
to the experience in the Recycler, the electron cloud gradually builds up over
multiple turns inside the combined function magnets and can reach final
intensities orders of magnitude greater than in a pure dipole. Since the
Booster synchrotron also incorporates combined function magnets, it is
important to measure the presence of electron cloud. The presence or apparent
absence of the electron cloud was investigated using two different methods:
measuring bunch-by-bunch tune shift by changing the bunch train structure at
different intensities and propagating a microwave carrier signal through the
beampipe and analyzing the phase modulation of the signal. This paper presents
the results of the two methods and corresponding simulation results conducted
using PyECLOUD software.Comment: International Particle Accelerator Conference 202
Design and construction of the MicroBooNE Cosmic Ray Tagger system
The MicroBooNE detector utilizes a liquid argon time projection chamber
(LArTPC) with an 85 t active mass to study neutrino interactions along the
Booster Neutrino Beam (BNB) at Fermilab. With a deployment location near ground
level, the detector records many cosmic muon tracks in each beam-related
detector trigger that can be misidentified as signals of interest. To reduce
these cosmogenic backgrounds, we have designed and constructed a TPC-external
Cosmic Ray Tagger (CRT). This sub-system was developed by the Laboratory for
High Energy Physics (LHEP), Albert Einstein center for fundamental physics,
University of Bern. The system utilizes plastic scintillation modules to
provide precise time and position information for TPC-traversing particles.
Successful matching of TPC tracks and CRT data will allow us to reduce
cosmogenic background and better characterize the light collection system and
LArTPC data using cosmic muons. In this paper we describe the design and
installation of the MicroBooNE CRT system and provide an overview of a series
of tests done to verify the proper operation of the system and its components
during installation, commissioning, and physics data-taking
Novel event classification based on spectral analysis of scintillation waveforms in Double Chooz
Liquid scintillators are a common choice for neutrino physics experiments, but their capabilities to perform background rejection by scintillation pulse shape discrimination is generally limited in large detectors. This paper describes a novel approach for a pulse shape based event classification developed in the context of the Double Chooz reactor antineutrino experiment. Unlike previous implementations, this method uses the Fourier power spectra of the scintillation pulse shapes to obtain event-wise information. A classification variable built from spectral information was able to achieve an unprecedented performance, despite the lack of optimization at the detector design level. Several examples of event classification are provided, ranging from differentiation between the detector volumes and an efficient rejection of instrumental light noise, to some sensitivity to the particle type, such as stopping muons, ortho-positronium formation, alpha particles as well as electrons and positrons. In combination with other techniques the method is expected to allow for a versatile and more efficient background rejection in the future, especially if detector optimization is taken into account at the design level
Rejecting cosmic background for exclusive neutrino interaction studies with Liquid Argon TPCs; a case study with the MicroBooNE detector
Cosmic ray (CR) interactions can be a challenging source of background for
neutrino oscillation and cross-section measurements in surface detectors. We
present methods for CR rejection in measurements of charged-current
quasielastic-like (CCQE-like) neutrino interactions, with a muon and a proton
in the final state, measured using liquid argon time projection chambers
(LArTPCs). Using a sample of cosmic data collected with the MicroBooNE
detector, mixed with simulated neutrino scattering events, a set of event
selection criteria is developed that produces an event sample with minimal
contribution from CR background. Depending on the selection criteria used a
purity between 50% and 80% can be achieved with a signal selection efficiency
between 50% and 25%, with higher purity coming at the expense of lower
efficiency. While using a specific dataset from the MicroBooNE detector and
selection criteria values optimized for CCQE-like events, the concepts
presented here are generic and can be adapted for various studies of exclusive
{\nu}{\mu} interactions in LArTPCs.Comment: 12 pages, 10 figures, 1 tabl
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