17,740 research outputs found
Science Requirements and Conceptual Design for a Polarized Medium Energy Electron-Ion Collider at Jefferson Lab
This report presents a brief summary of the science opportunities and program
of a polarized medium energy electron-ion collider at Jefferson Lab and a
comprehensive description of the conceptual design of such a collider based on
the CEBAF electron accelerator facility.Comment: 160 pages, ~93 figures This work was supported by the U.S. Department
of Energy, Office of Nuclear Physics, under Contract No. DE-AC05-06OR23177,
DE-AC02-06CH11357, DE-AC05-060R23177, and DESC0005823. The U.S. Government
retains a non-exclusive, paid-up, irrevocable, world-wide license to publish
or reproduce this manuscript for U.S. Government purpose
The model of an anomaly detector for HiLumi LHC magnets based on Recurrent Neural Networks and adaptive quantization
This paper focuses on an examination of an applicability of Recurrent Neural
Network models for detecting anomalous behavior of the CERN superconducting
magnets. In order to conduct the experiments, the authors designed and
implemented an adaptive signal quantization algorithm and a custom GRU-based
detector and developed a method for the detector parameters selection. Three
different datasets were used for testing the detector. Two artificially
generated datasets were used to assess the raw performance of the system
whereas the 231 MB dataset composed of the signals acquired from HiLumi magnets
was intended for real-life experiments and model training. Several different
setups of the developed anomaly detection system were evaluated and compared
with state-of-the-art OC-SVM reference model operating on the same data. The
OC-SVM model was equipped with a rich set of feature extractors accounting for
a range of the input signal properties. It was determined in the course of the
experiments that the detector, along with its supporting design methodology,
reaches F1 equal or very close to 1 for almost all test sets. Due to the
profile of the data, the best_length setup of the detector turned out to
perform the best among all five tested configuration schemes of the detection
system. The quantization parameters have the biggest impact on the overall
performance of the detector with the best values of input/output grid equal to
16 and 8, respectively. The proposed solution of the detection significantly
outperformed OC-SVM-based detector in most of the cases, with much more stable
performance across all the datasets.Comment: Related to arXiv:1702.0083
Commissioning strategies and methods
Accelerator beam commissioning is a challenging and exciting period. It is
generally the first integrated operation of the many systems in an accelerator
and, most importantly, of the beam. First, general preparation is discussed.
Then general methods for initial beam commissioning are described, including
methods for transverse and longitudinal beam set-up. The particular emphasis
here is on tuning methods for linear accelerators.Comment: 16 pages, contribution to the CAS - CERN Accelerator School: Course
on High Power Hadron Machines; 24 May - 2 Jun 2011, Bilbao, Spai
Linear Accelerator Test Facility at LNF Conceptual Design Report
Test beam and irradiation facilities are the key enabling infrastructures for
research in high energy physics (HEP) and astro-particles. In the last 11 years
the Beam-Test Facility (BTF) of the DA{\Phi}NE accelerator complex in the
Frascati laboratory has gained an important role in the European
infrastructures devoted to the development and testing of particle detectors.
At the same time the BTF operation has been largely shadowed, in terms of
resources, by the running of the DA{\Phi}NE electron-positron collider. The
present proposal is aimed at improving the present performance of the facility
from two different points of view: extending the range of application for the
LINAC beam extracted to the BTF lines, in particular in the (in some sense
opposite) directions of hosting fundamental physics and providing electron
irradiation also for industrial users; extending the life of the LINAC beyond
or independently from its use as injector of the DA{\Phi}NE collider, as it is
also a key element of the electron/positron beam facility. The main lines of
these two developments can be identified as: consolidation of the LINAC
infrastructure, in order to guarantee a stable operation in the longer term;
upgrade of the LINAC energy, in order to increase the facility capability
(especially for the almost unique extracted positron beam); doubling of the BTF
beam-lines, in order to cope with the signicant increase of users due to the
much wider range of applications.Comment: 71 page
Penetrating particle ANalyzer (PAN)
PAN is a scientific instrument suitable for deep space and interplanetary
missions. It can precisely measure and monitor the flux, composition, and
direction of highly penetrating particles (100 MeV/nucleon) in deep
space, over at least one full solar cycle (~11 years). The science program of
PAN is multi- and cross-disciplinary, covering cosmic ray physics, solar
physics, space weather and space travel. PAN will fill an observation gap of
galactic cosmic rays in the GeV region, and provide precise information of the
spectrum, composition and emission time of energetic particle originated from
the Sun. The precise measurement and monitoring of the energetic particles is
also a unique contribution to space weather studies. PAN will map the flux and
composition of penetrating particles, which cannot be shielded effectively,
precisely and continuously, providing valuable input for the assessment of the
related health risk, and for the development of an adequate mitigation
strategy. PAN has the potential to become a standard on-board instrument for
deep space human travel.
PAN is based on the proven detection principle of a magnetic spectrometer,
but with novel layout and detection concept. It will adopt advanced particle
detection technologies and industrial processes optimized for deep space
application. The device will require limited mass (~20 kg) and power (~20 W)
budget. Dipole magnet sectors built from high field permanent magnet Halbach
arrays, instrumented in a modular fashion with high resolution silicon strip
detectors, allow to reach an energy resolution better than 10\% for nuclei from
H to Fe at 1 GeV/n
Quantum Communication with Quantum Dot Spins
Single electron spins in quantum dots are attractive for quantum
communication because of their expected long coherence times. We propose a
method to create entanglement between two remote spins based on the coincident
detection of two photons emitted by the dots. Local nodes of several qubits can
be realized using the dipole-dipole interaction between trions in neighboring
dots and spectral addressing, allowing the realization of quantum repeater
protocols. We have performed a detailed feasibility study of our proposal based
on tight-binding calculations of quantum dot properties.Comment: 4 pages, 2 figures, new and improved version, explicit performance
estimate
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