121776162
ARENA 2008 acoustic detection conference summary
The principle for detecting ultra-high energy neutrinos acoustically is briefly introduced. Current activities in this field are numerous and many have been reported at this conference. They include, e.g., the co-deployment of acoustic sensors in optical Cherenkov neutrino telescopes, the analysis of acoustic data from the existing hydrophone arrays for calibration and noise determination purposes, the design of bespoke acoustic sensors and the development of signal processing techniques. A digest of the status of current acoustic detection projects is presented. The work of the authors referenced in this text can be found elsewhere in these proceedings.
13361149
Recent results from the ANTARES deep-sea neutrino telescope
Abstract The ANTARES collaboration is currently constructing a large area neutrino telescope for deployment in the Mediterranean Sea. The ANTARES detector will be located 30 km off the southern French coast. After introducing the detection principle, the details of the detector design are considered. In describing the ANTARES site, emphasis is placed on results from more than 25 deployments of autonomous mooring lines instrumented with various measuring devices. These deployments have led to an understanding of the water and environmental parameters at the site. A neutrino telescope can address a wide-ranging scientific programme which covers topics in particle physics and astrophysics, a brief summary of this programme is made, following which, aspects of the expected detector performance, specifically the angular and energy resolutions, are discussed. Finally, the results from a “demonstrator string” are presented. This is a full-scale, part-instrumented string which was deployed in the Mediterranean Sea in late 1999. The string has provided the first recorded down-going muons which have been subsequently reconstructed and analysed, examples of these events and their properties are given. The demonstrator was also equipped with the instrumentation required for determining the position, inclination and orientation of the string as a function of time. The performance of these systems is also discussed.
123448556
The Acoustic Detection of Ultra-High Energy Neutrinos - a Status Report
An overview is presented of current worldwide activities in the field of the acoustic detection of ultra-high energy neutrinos. Emphasis is placed on recent results from test experimental setups, simulation work, sensitivity calculations and on data taken at deep-water deployments.
15848028
PRECISION TESTS OF THE STANDARD MODEL AT LEP AND RESULTS FROM THE 4-JET FINAL STATE AT LEP 1.5
First a short review is made of current limits on the Standard Model as derived from the electroweak sector concerning the Z boson at LEP. The second part of the paper presents an analysis of the four jet nal state at ALEPH, this analysis was performed on LEP data taken at centre of mass energies of 130 and 136 GeV. The results presented here are from approximate totals 1 of 12.3 millionhadronic Z decays and 1.3 million leptonic decays recorded by the four LEP experiments during the years 1990 to 1995 inclusive. These statistics permit a precise study of the Standard Model though the coupling of the Z boson to fermion pairs. This reaction is modiied by vacuum polarization corrections in the propogator such as t-quark and Higgs boson loops thus allowing a determination of m top and m Higgs to be made via indirect measurements. It should be noted that results for 1993 onwards are regarded as preliminary for all 4 LEP experiments. In order to combine electroweak results a common reference point is required. Each of the LEP experiments measures the leptonic and hadronic total cross-sections and the leptonic forward-backward asymmetries from angular distributions in cos. These results are tted 1 according to the Z 0 lineshape to give 9 parameters, namely the Z boson mass and width, (m Z , ? Z), the pole hadronic cross-section, (0 h), the ratios of the hadronic to leptonic partial widths, (R e , R , R) and the leptonic pole asymmetries (A 0; e FB ,A 0; FB ,A 0; FB). These 9 parameters are then combined 1 , along with the individual experimental covariance matices and common systematic errors to give the results in Table 1. The nal two entries in Table 1 represent the values of the partial width ratio and the pole asymmetry under the assumption of lepton universality. This assumption is further explored in Figure 1 where R ` is plotted against A 0;` FB individually for the 3 lepton species and also under the assumption of lepton universality. The accuracy of these results is remarkable, with the Z boson mass being measured to 24 parts per million.
119419425
Acoustic detection of UHE neutrinos – the ACORNE project
An interesting new possibility of detection of ultra-high energy (UHE) neutrinos is that of acoustic detection whereby the acoustic pressure pulse generated as a UHE neutrino interacts in a suitable medium such as water or ice is detected by an array of acoustic sensors. Recent years have seen something of a renaissance of this field and there are currently a number of activities worldwide to assess the potential of this technique. The UK-based ACORNE collaboration is one of these activities; ACORNE has access to the QinetiQ underwater acoustic range off Rona, an island off the North-West coast of Scotland. The poster will summarise ACORNE's R&D work, including simulation of the thermoacoustic emission of neutrino-induced particle cascades, reconstruction of event vertices and the effects of refraction, potential neutrino flux sensitivities from large area hydrophone arrays, a study transducer based calibration techniques and an analysis of the first acoustic data recorded by the Rona hydrophone array.
5995908
Probing quantum decoherence in atmospheric neutrino oscillations with a neutrino telescope
Quantum decoherence, the evolution of pure states into mixed states, may be a feature of quantum gravity. In this paper, we show how these effects can be modelled for atmospheric neutrinos and illustrate how the standard oscillation picture is modified. We examine how neutrino telescopes, such as ANTARES, are able to place upper bounds on these quantum decoherence effects.
59360505
SYNCHROTRON RADIATION IN THE INTERACTION REGION FOR A RING-RING AND LINAC-RING LHeC
The Large Hadron electron Collider (LHeC) aims at bringing hadron-lepton collisions to CERN with centre of mass energies in the TeV scale. The LHeC will utilise the existing LHC storage ring with the addition of a 60 GeV electron accelerator. The electron beam will be stored and accelerated in either a storage ring in the LHC tunnel (Ring-Ring) or a linac tangent to the LHC tunnel (LinacRing). Synchrotron Radiation (SR) in the Interaction Region (IR) of this machine requires an iterative design process in which luminosity is optimised while the SR is minimised. This process also requires attention to be given to the detector as the beam pipe must be designed such that disturbing effects, such as out-gassing and background scattering, are minimised while the tracker remains close to the IP thus maximising the acceptance of the experiment. The machinery of GEANT4 has been used to simulate the SR load in the IR and also to design absorbers/masks to shield SR from backscattering into the detector or propagating with the electron beam. The outcome of these simulations, as well as cross checks, are described in the accompanying paper which characterises the current status of the IR design for both the Ring-Ring and Linac-Ring options of the LHeC in terms of SR.
96445234
Optics and lattice optimizations for the LHC upgrade project
The luminosity upgrade of the LHC collider at CERN is based on a strong focusing scheme to reach lowest values of the beta function at the collision points. Several issues have to be addressed in this context, that are considered as mid term goals for the optimisation of the lattice and beam optics: Firstly a number of beam optics have been developed to establish a baseline for the hardware R&D, and that will define the specifications for the new magnets that will be needed, in Nb3Sn as well as in NbTi technology. Secondly, the need for sufficient flexibility of the beam optics especially for smallest ! * values, the need for a smooth transition between the injection and the collision optics, the comparison of the optics performance between flat and round beams and finally different ways to optimise the chromatic correction, including the study of local correction schemes. This paper presents the status of this work, which is a result of an international collaboration, and summarises the main parameters that are foreseen to reach the HL-LHC luminosity goal.