arXiv subjects

K. Long

Publications and source records attributed to K. Long.

45 records · Page 3Linked to original sources

arXiv2012

nuSTORM: Neutrinos from STORed Muons

The results of LSND and MiniBooNE, along with the recent papers on a possible reactor neutrino flux anomaly give tantalizing hints of new physics. Models beyond the neutrino-SM have been developed to explain these results and involve one or more additional neutrinos that are non-interacting or "sterile." Neutrino beams produced from the decay of muons in a racetrack-like decay ring provide a powerful way to study this potential new physics. In this Letter of Intent, we describe a facility, nuSTORM, "Neutrinos from STORed Muons," and an appropriate far detector for neutrino oscillation searches at short baseline. We present sensitivity plots that indicated that this experimental approach can provide over 10 sigma confirmation or rejection of the LSND/MinBooNE results. In addition we indicate how the facility can be used to make precision neutrino interaction cross section measurements important to the next generation of long-baseline neutrino oscillation experiments.

hep-ex↗

arXiv2012

Light Sterile Neutrinos: A White Paper

This white paper addresses the hypothesis of light sterile neutrinos based on recent anomalies observed in neutrino experiments and the latest astrophysical data.

hep-ph↗

arXiv2011

Interim Design Report

The International Design Study for the Neutrino Factory (the IDS-NF) was established by the community at the ninth "International Workshop on Neutrino Factories, super-beams, and beta- beams" which was held in Okayama in August 2007. The IDS-NF mandate is to deliver the Reference Design Report (RDR) for the facility on the timescale of 2012/13. In addition, the mandate for the study [3] requires an Interim Design Report to be delivered midway through the project as a step on the way to the RDR. This document, the IDR, has two functions: it marks the point in the IDS-NF at which the emphasis turns to the engineering studies required to deliver the RDR and it documents baseline concepts for the accelerator complex, the neutrino detectors, and the instrumentation systems. The IDS-NF is, in essence, a site-independent study. Example sites, CERN, FNAL, and RAL, have been identified to allow site-specific issues to be addressed in the cost analysis that will be presented in the RDR. The choice of example sites should not be interpreted as implying a preferred choice of site for the facility.

hep-ex↗

arXiv2009

Fully Automated Approaches to Analyze Large-Scale Astronomy Survey Data

Observational astronomy has changed drastically in the last decade: manually driven target-by-target instruments have been replaced by fully automated robotic telescopes. Data acquisition methods have advanced to the point that terabytes of data are flowing in and being stored on a daily basis. At the same time, the vast majority of analysis tools in stellar astrophysics still rely on manual expert interaction. To bridge this gap, we foresee that the next decade will witness a fundamental shift in the approaches to data analysis: case-by-case methods will be replaced by fully automated pipelines that will process the data from their reduction stage, through analysis, to storage. While major effort has been invested in data reduction automation, automated data analysis has mostly been neglected despite the urgent need. Scientific data mining will face serious challenges to identify, understand and eliminate the sources of systematic errors that will arise from this automation. As a special case, we present an artificial intelligence (AI) driven pipeline that is prototyped in the domain of stellar astrophysics (eclipsing binaries in particular), current results and the challenges still ahead.

astro-ph.IM↗

arXiv2007

MICE: The International Muon Ionization Cooling Experiment

Muon storage rings have been proposed for use as a source of high-energy neutrino beams (the Neutrino Factory) and as the basis for a high-energy lepton-antilepton collider (the Muon Collider). The Neutrino Factory is widely believed to be the machine of choice for the search for leptonic CP violation while the Muon Collider may prove to be the most practical route to multi-TeV lepton-antilepton collisions. The baseline conceptual designs for each of these facilities requires the phase-space compression (cooling) of the muon beams prior to acceleration. The short muon lifetime makes it impossible to employ traditional techniques to cool the beam while maintaining the muon-beam intensity. Ionization cooling, a process in which the muon beam is passed through a series of liquid-hydrogen absorbers followed by accelerating RF cavities, is the technique proposed to cool the muon beam. The international Muon Ionization Cooling Experiment (MICE) collaboration will carry out a systematic study of ionization cooling. The MICE experiment, which is under construction at the Rutherford Appleton Laboratory, will begin to take data late this year. The MICE cooling channel, the instrumentation and the implementation at the Rutherford Appleton Laboratory are described together with the predicted performance of the channel and the measurements that will be made.

physics.acc-ph↗

arXiv2005

The scattering of muons in low Z materials

This paper presents the measurement of the scattering of 172 MeV/c muons in assorted materials, including liquid hydrogen, motivated by the need to understand ionisation cooling for muon acceleration. Data are compared with predictions from the Geant 4 simulation code and this simulation is used to deconvolute detector effects. The scattering distributions obtained are compared with the Moliere theory of multiple scattering and, in the case of liquid hydrogen, with ELMS. With the exception of ELMS, none of the models are found to provide a good description of the data. The results suggest that ionisation cooling will work better than would be predicted by Geant 4.7.0p01.

hep-ex↗

arXiv2005

Neutrino Factory R&D

Elegant experiments are being carried out, or are in preparation, to improve the precision with which the solar and atmospheric neutrino-oscillation parameters are known, and to attempt to make a first measurement of the small mixing angle $θ_{13}$. The compelling case for the development of an accelerator-based neutrino source to serve the programme of precision measurements of neutrino oscillations and sensitive searches for leptonic-CP violation that is required to follow these experiments is briefly reviewed. The Neutrino Factory, an intense high-energy neutrino source based on a stored muon beam, is widely believed to yield a precision and sensitivity superior to other proposed second-generation facilities. The alternatives are identified and the case for a critical comparison of the performance of the various options is presented. Highlights of the exciting international R&D programmes which are designed to demonstrate the feasibility of the required techniques are then reviewed. The steps that the international community is taking to produce, by the end of the decade, a full conceptual design for the facility are described. The ambition of the Neutrino Factory community is to demonstrate the feasibility of a cost-effective design such that, should forthcoming measurements show that it is required, the facility could be brought into operation in the second half of the next decade.

physics.ins-det↗

arXiv2002

QCD at high energy (experiments)

Recent measurements of QCD interactions involving large momentum transfers are reviewed. The status of measurements of the strong coupling constant is summarised. Recent developments in the measurement and interpretation of deep inelastic scattering, proton-anti-proton collisions and two-photon processes are discussed. While QCD at next-to-leading order gives a qualitative description of many processes, next-to-NLO calculations are now required to allow quantitative information to be extracted from hadron-initiated multijet data. This is illustrated by a discussion of recent data on the photoproduction of dijet events at HERA.

hep-ex↗

arXiv1999

High Q^2 Deep Inelastic Scattering at HERA

High Q^2 NC and CC cross-sections as measured at HERA can give information on two distinct areas of current interest. Firstly, supposing that all the electroweak parameters are well known, these cross-sections may be used to give information on parton distributions at high x and high Q^2. Secondly, supposing that parton distributions are well known, after evolution in Q^2 from the kinematic regime where they are already measured, these cross-sections can be used to give information on electroweak parameters in a process where the exchanged boson is `spacelike' rather than `timelike'. WG1 addressed itself to clarifying the limits of our present and possible future knowledge on both these areas.

hep-ph↗