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Asfandiyarov, R.

Publications and source records attributed to Asfandiyarov, R..

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Transverse emittance reduction in muon beams by ionization cooling

Accelerated muon beams have been considered for the next-generation studies of high-energy lepton–antilepton collisions and neutrino oscillations. However, high-brightness muon beams have not yet been produced. The main challenge for muon acceleration and storage stems from the large phase-space volume occupied by the beam, derived from the production mechanism of muons through the decay of pions. The phase-space volume of the muon beam can be decreased through ionization cooling. Here we show that ionization cooling leads to a reduction in the transverse emittance of muon beams that traverse lithium hydride or liquid hydrogen absorbers in the Muon Ionization Cooling Experiment. Our results represent a substantial advance towards the realization of muon-based facilities that could operate at the energy and intensity frontiers.

43 PARTICLE ACCELERATORS↗
DOE OSTI2021

Performance of the MICE diagnostic system

Muon beams of low emittance provide the basis for the intense, well-characterised neutrino beams of a neutrino factory and for multi-TeV lepton-antilepton collisions at a muon collider. The international Muon Ionization Cooling Experiment (MICE) has demonstrated the principle of ionization cooling, the technique by which it is proposed to reduce the phase-space volume occupied by the muon beam at such facilities. This paper documents the performance of the detectors used in MICE to measure the muon-beam parameters, and the physical properties of the liquid hydrogen energy absorber during running.

43 PARTICLE ACCELERATORS↗
DOE OSTI2019

MAUS: the MICE analysis user software

The Muon Ionization Cooling Experiment (MICE) collaboration has developed the MICE Analysis User Software (MAUS) to simulate and analyze experimental data. It serves as the primary codebase for the experiment, providing for offline batch simulation and reconstruction as well as online data quality checks. The software provides both traditional particle-physics functionalities such as track reconstruction and particle identification, and accelerator physics functions, such as calculating transfer matrices and emittances. The code design is object orientated, but has a top-level structure based on the Map-Reduce model. This allows for parallelization to support live data reconstruction during data-taking operations. MAUS allows users to develop in either Python or C++ and provides APIs for both. Various software engineering practices from industry are also used to ensure correct and maintainable code, including style, unit and integration tests, continuous integration and load testing, code reviews, and distributed version control. The software framework and the simulation and reconstruction capabilities are described.

47 OTHER INSTRUMENTATION↗
DOE OSTI2019

First particle-by-particle measurement of emittance in the Muon Ionization Cooling Experiment

The Muon Ionization Cooling Experiment (MICE) collaboration seeks to demonstrate the feasibility of ionization cooling, the technique by which it is proposed to cool the muon beam at a future neutrino factory or muon collider. The emittance is measured from an ensemble of muons assembled from those that pass through the experiment. A pure muon ensemble is selected using a particle-identification system that can reject efficiently both pions and electrons. The position and momentum of each muon are measured using a high-precision scintillating-fibre tracker in a 4 T solenoidal magnetic field. This paper presents the techniques used to reconstruct the phase-space distributions in the upstream tracking detector and reports the first particle-by-particle measurement of the emittance of the MICE Muon Beam as a function of muon-beam momentum.

43 PARTICLE ACCELERATORS↗
DOE OSTI2016

Pion contamination in the MICE muon beam

Here, the international Muon Ionization Cooling Experiment (MICE) will perform a systematic investigation of ionization cooling with muon beams of momentum between 140 and 240\,MeV/c at the Rutherford Appleton Laboratory ISIS facility. The measurement of ionization cooling in MICE relies on the selection of a pure sample of muons that traverse the experiment. To make this selection, the MICE Muon Beam is designed to deliver a beam of muons with less than $\sim$1% contamination. To make the final muon selection, MICE employs a particle-identification (PID) system upstream and downstream of the cooling cell. The PID system includes time-of-flight hodoscopes, threshold-Cherenkov counters and calorimetry. The upper limit for the pion contamination measured in this paper is $f_\pi < 1.4\%$ at 90% C.L., including systematic uncertainties. Therefore, the MICE Muon Beam is able to meet the stringent pion-contamination requirements of the study of ionization cooling.

43 PARTICLE ACCELERATORS↗
DOE OSTI2015

Physics potential of a long-baseline neutrino oscillation experiment using a J-PARC neutrino beam and Hyper-Kamiokande

Hyper-Kamiokande will be a next generation underground water Cherenkov detector with a total (fiducial) mass of 0.99 (0.56) million metric tons, approximately 20 (25) times larger than that of Super-Kamiokande. One of the main goals of Hyper-Kamiokande is the study of CP asymmetry in the lepton sector using accelerator neutrino and anti-neutrino beams. In this paper, the physics potential of a long baseline neutrino experiment using the Hyper-Kamiokande detector and a neutrino beam from the J-PARC proton synchrotron is presented. The analysis uses the framework and systematic uncertainties derived from the ongoing T2K experiment. With a total exposure of 7.5 MW × 107 sec integrated proton beam power (corresponding to 1.56×1022 protons on target with a 30 GeV proton beam) to a 2.5-degree off-axis neutrino beam, it is expected that the leptonic CP phase δCP can be determined to better than 19 degrees for all possible values of δCP, and CP violation can be established with a statistical significance of more than 3σ (5σ) for 76% (58%) of the δCP parameter space. Using both νe appearance and νμ disappearance data, the expected 1σ uncertainty of sin2θ23 is 0.015(0.006) for sin2θ23=0.5(0.45).

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2014

Light sterile neutrino sensitivity at the nuSTORM facility

A facility that can deliver beams of electron and muon neutrinos from the decay of a stored muon beam has the potential to unambiguously resolve the issue of the evidence for light sterile neutrinos that arises in short-baseline neutrino oscillation experiments and from estimates of the effective number of neutrino flavors from fits to cosmological data. In this paper, we show that the nuSTORM facility, with stored muons of 3.8 GeV/c ± 10%, will be able to carry out a conclusive muon neutrino appearance search for sterile neutrinos and test the LSND and MiniBooNE experimental signals with 10σ sensitivity, even assuming conservative estimates for the systematic uncertainties. This experiment would add greatly to our knowledge of the contribution of light sterile neutrinos to the number of effective neutrino flavors from the abundance of primordial helium production and from constraints on neutrino energy density from the cosmic microwave background. Here, the appearance search is complemented by a simultaneous muon neutrino disappearance analysis that will facilitate tests of various sterile neutrino models.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2013

Characterisation of the muon beams for the Muon Ionisation Cooling Experiment

A novel single-particle technique to measure emittance has been developed and used to characterise seventeen different muon beams for the Muon Ionisation Cooling Experiment (MICE). The muon beams, whose mean momenta vary from 171 to 281 MeV/c, have emittances of approximately 1.5--2.3 \pi mm-rad horizontally and 0.6--1.0 \pi mm-rad vertically, a horizontal dispersion of 90--190 mm and momentum spreads of about 25 MeV/c. There is reasonable agreement between the measured parameters of the beams and the results of simulations. The beams are found to meet the requirements of MICE.

43 PARTICLE ACCELERATORS↗
DOE OSTI2013

nuSTORM - Neutrinos from STORed Muons: Proposal to the Fermilab PAC

The nuSTORM facility has been designed to deliver beams of electron neutrinos and muon neutrinos (and their anti-particles) from the decay of a stored muon beam with a central momentum of 3.8 GeV/c and a momentum acceptance of 10%. The facility is unique in that it will: 1. Allow searches for sterile neutrinos of exquisite sensitivity to be carried out; 2. Serve future long- and short-baseline neutrino-oscillation programs by providing definitive measurements of electron neutrino and muon neutrino scattering cross sections off nuclei with percent-level precision; and 3. Constitutes the crucial first step in the development of muon accelerators as a powerful new technique for particle physics. The document describes the facility in detail and demonstrates its physics capabilities. This document was submitted to the Fermilab Physics Advisory Committee in consideration for Stage I approval.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2013

Neutrinos from Stored Muons nuSTORM: Expression of Interest

The nuSTORM facility has been designed to deliver beams of electron and muon neutrinos from the decay of a stored muon beam with a central momentum of 3.8 GeV/c and a momentum spread of 10%. The facility is unique in that it will: serve the future long- and short-baseline neutrino-oscillation programmes by providing definitive measurements of electron-neutrino- and muon-neutrino-nucleus cross sections with percent-level precision; allow searches for sterile neutrinos of exquisite sensitivity to be carried out; and constitute the essential first step in the incremental development of muon accelerators as a powerful new technique for particle physics. Of the world's proton-accelerator laboratories, only CERN and FNAL have the infrastructure required to mount nuSTORM. Since no siting decision has yet been taken, the purpose of this Expression of Interest (EoI) is to request the resources required to: investigate in detail how nuSTORM could be implemented at CERN; and develop options for decisive European contributions to the nuSTORM facility and experimental programme wherever the facility is sited. The EoI defines a two-year programme culminating in the delivery of a Technical Design Report.

43 PARTICLE ACCELERATORS↗
DOE OSTI2012

Search for lepton flavour violation in the eμ continuum with the ATLAS detector in $\sqrt{s} = 7~\mbox{TeV}$ pp collisions at the LHC

This paper presents a search for the t-channel exchange of an R-parity violating scalar top quark ($\sim\atop{t}$) in the e ± μ ∓ continuum using 2.1 fb 1 of data collected by the ATLAS detector in √s = 7 TeV pp collisions at the Large Hadron Collider. Data are found to be consistent with the expectation from the Standard Model backgrounds. Limits on R-parity-violating couplings at 95 % C.L. are calculated as a function of the scalar top mass (m$_t^-$). The upper limits on the production cross section for pp→eμX, through the t-channel exchange of a scalar top quark, ranges from 170 fb for m$_t^-$ = 95 GeV to 30 fb for m$_t^-$ = 1000 GeV.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2012

Measurements of the electron and muon inclusive cross-sections in proton-proton collisions at root s=7 TeV with the ATLAS detector

This Letter presents measurements of the differential cross-sections for inclusive electron and muon production in proton-proton collisions at a centre-of-mass energy of {radical}s = 7 TeV, using data collected by the ATLAS detector at the LHC. The muon cross-section is measured as a function of pT in the range 4 < pT < 100 GeV and within pseudorapidity |{eta}| < 2.5. In addition the electron and muon cross-sections are measured in the range 7 < pT < 26 GeV and within |{eta}| < 2.0, excluding 1.37 < |{eta}| < 1.52. Integrated luminosities of 1.3 pb{sup -1} and 1.4 pb{sup -1} are used for the electron and muon measurements, respectively. After subtraction of the W/Z/{gamma}{sm_bullet} contribution, the differential cross-sections are found to be in good agreement with theoretical predictions for heavy-flavour production obtained from Fixed Order NLO calculations with NLL high-pT resummation, and to be sensitive to the effects of NLL resummation.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2012

Measurement of the isolated diphoton cross section in p p collisions at s = 7 TeV with the ATLAS detector

Here, the ATLAS experiment has measured the production cross section of events with two isolated photons in the final state, in proton-proton collisions at √s = 7 TeV. The full data set acquired in 2010 is used, corresponding to an integrated luminosity of 37 pb –1 . The background, consisting of hadronic jets and isolated electrons, is estimated with fully data-driven techniques and subtracted. The differential cross sections, as functions of the di-photon mass (m γγ ), total transverse momentum (pT, γγ ), and azimuthal separation (ΔΦ γγ ), are presented and compared to the predictions of next-to-leading-order QCD.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗