101 research outputs found
Performance of prototypes for the ALICE electromagnetic calorimeter
The performance of prototypes for the ALICE electromagnetic sampling
calorimeter has been studied in test beam measurements at FNAL and CERN. A
array of final design modules showed an energy resolution of about
11% / 1.7 % with a uniformity of the response
to electrons of 1% and a good linearity in the energy range from 10 to 100 GeV.
The electromagnetic shower position resolution was found to be described by 1.5
mm 5.3 mm /. For an electron identification
efficiency of 90% a hadron rejection factor of was obtained.Comment: 10 pages, 10 figure
Three-component variometer based on a scalar potassium sensor
Abstract A new variometer is developed comprising a fast-response scalar optically pumped potassium magnetometer inside a rotating magnetic field created by a two-dimensional coil system mounted on a quartz frame. The variometer measures three components of the Earth's field: the total field intensity and two transverse components. The theoretically predicted accuracy of the field component measurement is not worse than 0.1 nT. The noise-limited sensitivity measured in a quiet magnetic field has been proved to be not worse than 25 pT rms at 0.2 s and 30 pT rms at 1 min; comparison with a proton vector magnetometer and a fluxgate magnetometer shows 1.5 nT p-t-p daily deviation
Particle identification studies with a full-size 4-GEM prototype for the ALICE TPC upgrade
A large Time Projection Chamber is the main device for tracking and
charged-particle identification in the ALICE experiment at the CERN LHC. After
the second long shutdown in 2019/20, the LHC will deliver Pb beams colliding at
an interaction rate of about 50 kHz, which is about a factor of 50 above the
present readout rate of the TPC. This will result in a significant improvement
on the sensitivity to rare probes that are considered key observables to
characterize the QCD matter created in such collisions. In order to make full
use of this luminosity, the currently used gated Multi-Wire Proportional
Chambers will be replaced. The upgrade relies on continuously operated readout
detectors employing Gas Electron Multiplier technology to retain the
performance in terms of particle identification via the measurement of the
specific energy loss by ionization d/d. A full-size readout chamber
prototype was assembled in 2014 featuring a stack of four GEM foils as an
amplification stage. The performance of the prototype was evaluated in a test
beam campaign at the CERN PS. The d/d resolution complies with both the
performance of the currently operated MWPC-based readout chambers and the
challenging requirements of the ALICE TPC upgrade program. Detailed simulations
of the readout system are able to reproduce the data.Comment: Submitted to NIM
The DIRC Particle Identification System for the BABAR Experiment
A new type of ring-imaging Cherenkov detector is being used for hadronic particle identification in the BABAR experiment at the SLAC B Factory (PEP-II). This detector is called DIRC, an acronym for Detection of Internally Reflected Cherenkov (Light). This paper will discuss the construction, operation and performance of the BABAR DIRC in detail
Design and Simulated Performance of Calorimetry Systems for the ECCE Detector at the Electron Ion Collider
We describe the design and performance the calorimeter systems used in the
ECCE detector design to achieve the overall performance specifications
cost-effectively with careful consideration of appropriate technical and
schedule risks. The calorimeter systems consist of three electromagnetic
calorimeters, covering the combined pseudorapdity range from -3.7 to 3.8 and
two hadronic calorimeters. Key calorimeter performances which include energy
and position resolutions, reconstruction efficiency, and particle
identification will be presented.Comment: 19 pages, 22 figures, 5 table
ECCE Sensitivity Studies for Single Hadron Transverse Single Spin Asymmetry Measurements
We performed feasibility studies for various single transverse spin
measurements that are related to the Sivers effect, transversity and the tensor
charge, and the Collins fragmentation function. The processes studied include
semi-inclusive deep inelastic scattering (SIDIS) where single hadrons (pions
and kaons) were detected in addition to the scattered DIS lepton. The data were
obtained in {\sc pythia}6 and {\sc geant}4 simulated e+p collisions at 18 GeV
on 275 GeV, 18 on 100, 10 on 100, and 5 on 41 that use the ECCE detector
configuration. Typical DIS kinematics were selected, most notably
GeV, and cover the range from to . The single spin
asymmetries were extracted as a function of and , as well as the
semi-inclusive variables , and . They are obtained in azimuthal moments
in combinations of the azimuthal angles of the hadron transverse momentum and
transverse spin of the nucleon relative to the lepton scattering plane. The
initially unpolarized MonteCarlo was re-weighted in the true kinematic
variables, hadron types and parton flavors based on global fits of fixed target
SIDIS experiments and annihilation data. The expected statistical
precision of such measurements is extrapolated to 10 fb and potential
systematic uncertainties are approximated given the deviations between true and
reconstructed yields. The impact on the knowledge of the Sivers functions,
transversity and tensor charges, and the Collins function has then been
evaluated in the same phenomenological extractions as in the Yellow Report. The
impact is found to be comparable to that obtained with the parameterized Yellow
Report detector and shows that the ECCE detector configuration can fulfill the
physics goals on these quantities.Comment: 22 pages, 22 figures, to be submitted to joint ECCE proposal NIM-A
volum
Open Heavy Flavor Studies for the ECCE Detector at the Electron Ion Collider
The ECCE detector has been recommended as the selected reference detector for
the future Electron-Ion Collider (EIC). A series of simulation studies have
been carried out to validate the physics feasibility of the ECCE detector. In
this paper, detailed studies of heavy flavor hadron and jet reconstruction and
physics projections with the ECCE detector performance and different magnet
options will be presented. The ECCE detector has enabled precise EIC heavy
flavor hadron and jet measurements with a broad kinematic coverage. These
proposed heavy flavor measurements will help systematically study the
hadronization process in vacuum and nuclear medium especially in the
underexplored kinematic region.Comment: Open heavy flavor studies with the EIC reference detector design by
the ECCE consortium. 11 pages, 11 figures, to be submitted to the Nuclear
Instruments and Methods
ECCE unpolarized TMD measurements
We performed feasibility studies for various measurements that are related to
unpolarized TMD distribution and fragmentation functions. The processes studied
include semi-inclusive Deep inelastic scattering (SIDIS) where single hadrons
(pions and kaons) were detected in addition to the scattered DIS lepton. The
single hadron cross sections and multiplicities were extracted as a function of
the DIS variables and , as well as the semi-inclusive variables ,
which corresponds to the momentum fraction the detected hadron carries relative
to the struck parton and , which corresponds to the transverse momentum of
the detected hadron relative to the virtual photon. The expected statistical
precision of such measurements is extrapolated to accumulated luminosities of
10 fb and potential systematic uncertainties are approximated given the
deviations between true and reconstructed yields.Comment: 12 pages, 9 figures, to be submitted in joint ECCE proposal NIM-A
volum
AI-assisted Optimization of the ECCE Tracking System at the Electron Ion Collider
The Electron-Ion Collider (EIC) is a cutting-edge accelerator facility that
will study the nature of the "glue" that binds the building blocks of the
visible matter in the universe. The proposed experiment will be realized at
Brookhaven National Laboratory in approximately 10 years from now, with
detector design and R&D currently ongoing. Notably, EIC is one of the first
large-scale facilities to leverage Artificial Intelligence (AI) already
starting from the design and R&D phases. The EIC Comprehensive Chromodynamics
Experiment (ECCE) is a consortium that proposed a detector design based on a
1.5T solenoid. The EIC detector proposal review concluded that the ECCE design
will serve as the reference design for an EIC detector. Herein we describe a
comprehensive optimization of the ECCE tracker using AI. The work required a
complex parametrization of the simulated detector system. Our approach dealt
with an optimization problem in a multidimensional design space driven by
multiple objectives that encode the detector performance, while satisfying
several mechanical constraints. We describe our strategy and show results
obtained for the ECCE tracking system. The AI-assisted design is agnostic to
the simulation framework and can be extended to other sub-detectors or to a
system of sub-detectors to further optimize the performance of the EIC
detector.Comment: 16 pages, 18 figures, 2 appendices, 3 table
- …