117604384
Dark Matter Prospects with the ANTARES Neutrino Telescope
The ANTARES collaboration is building a large-area telescope at the bottom of the Mediterranean Sea, capable of detecting high-energy neutrinos from a number of sources. Of particular interest here is the possibility of detecting the presence of neutralino dark matter at the centres of galactic sources via the annihilation of neutralinos into products containing high-energy neutrinos. The principle of detection of high-energy neutrinos and the ANTARES detector are introduced and the sensitivity of the first stage, 0.1 km2 ANTARES detector to neutralinos is presented, along with comparisons to theoretical predictions and direct detection experiments.
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.
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.
18645695
The recent operational performance of the CERN omega ring imaging cerenkov detector
We discuss the design and construction of the Time Projection chambers (TPCs) of the Omega Ring Imaging Cerenkov Detector (RICH). Details are given of the TPC high voltage system and its monitoring and control. In addition, the operation and monitoring of the readout is described together with results of tests on the performance of the front end amplifiers. The operation of the RICH TPCs and electronics during the first data run of WA69, in 1984, is discussed together with relevant results from laboratory tests. Results from the preliminary analysis of a sample of data from the 1984 run are also presented.
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.
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.
96441775
Interaction Region Optics for the Non-Interacting LHC Proton Beam at the LHeC
The Large Hadron Electron Collider project is a proposal to study e-p and e-A interactions at the LHC. Two electron accelerator designs are being studied; a linac and a synchrotron. In the synchrotron option, a 60GeV electron beam is collided with one of the LHC proton beams to provide high luminosity TeV-scale interactions. The interaction region for this scheme is complex and introduces a series of challenges due to the integration of the two machines. One of these is the optics of the second noninteracting proton beam. The second proton beam must not interfere with the LHeC experiment, but simultaneous running of the remaining LHC experiments requires that this beam must still circulate relatively undisturbed. This paper discusses methods to solve these challenges for the electron synchrotron design.
122838111
The high luminosity interaction region for a ring?ring Large Hadron Electron Collider
The Large Hadron Electron Collider (LHeC) project is a proposal for high luminosity TeV-scale electron–proton (ep) collisions at the LHC. The LHeC Conceptual Design Report presented an early overview of the machine, including an electron linac solution and a solution involving a 60 GeV electron storage ring. Here we present a new complete solution for the collision insertion of this electron ring, incorporating all constraints including those imposed by the LHC and, for the first time, proving the feasibility of ep collisions at a luminosity of ∼1033 cm−2s−1 in the LHC era. The solution presented offers high luminosity while maintaining the large detector coverage required by the particle physics programme. This negates the earlier need for two separate interaction region designs, one optimized for high luminosity at the cost of detector coverage, and the other for lower luminosity but higher coverage. Synchrotron radiation emission is also a major factor in electron accelerator design, and studies are presented showing the feasibility of the design in this regard. The design is found to be technically viable, solving the problem of TeV-scale, high luminosity and high coverage ep collisions at a ring–ring LHeC.