7735148
Improved measurement of muon antineutrino disappearance in MINOS.
We report an improved measurement of ν(μ) disappearance over a distance of 735 km using the MINOS detectors and the Fermilab Main Injector neutrino beam in a ν(μ)-enhanced configuration. From a total exposure of 2.95×10(20) protons on target, of which 42% have not been previously analyzed, we make the most precise measurement of Δm2=[2.62(-0.28)(+0.31)(stat)±0.09(syst)]×10(-3)  eV2 and constrain the ν(μ) mixing angle sin2(2θ)>0.75 (90% C.L.). These values are in agreement with Δm2 and sin2(2θ) measured for ν(μ), removing the tension reported in [P. Adamson et al. (MINOS), Phys. Rev. Lett. 107, 021801 (2011).].
40454478
The MINOS scintillator calorimeter system
The MINOS detectors will use extruded plastic scintillator strips, which are readout by wavelength-shifting fibres coupled to multi-pixel photodetectors. This technique provides excellent energy and spatial resolution. The MINOS detectors are described in detail along with results from the light output tests.
110729769
ATLAS pixel detector electronics and sensors
The silicon pixel tracking system for the ATLAS experiment at the Large Hadron Collider is described and the performance requirements are summarized. Detailed descriptions of the pixel detector electronics and the silicon sensors are given. The design, fabrication, assembly and performance of the pixel detector modules are presented. Data obtained from test beams as well as studies using cosmic rays are also discussed.
12668582
The Pierre Auger Observatory V : Enhancements
The southern Pierre Auger Observatory was designed to detect ultrahig h energy cosmic rays above 10 eV with high accuracy exploiting a hybrid detection technique. A surface arra y of 1660 water Cherenkov detectors on a 1500 m triangular grid covers an area of 3000 km. The atmosphere above the array is viewed by 24 wide angle telescopes. These telescopes observe the faint fluorescence light of the extensive air showers at dark moonless nights, i.e. with a duty cycle of about 15 %. As an enhancement to this baseline design o f the Auger Observatory three additional telescopes with elevated field of view were built and now constitute HEAT, the h igh-elevation Auger telescopes. These telescopes are similar to the 24 other fluorescence telescopes (FD) but c an be tilted by29 degrees upward. They cover an elevation range from30 to 58 degrees above horizon to enable the unbiased detection of nearby low en ergy air showers. Especially in combination with the detector information from an infill array of w ater tanks on a750m grid close to the HEAT site the energy range of high quality hybrid air shower measuremen ts is extended down to below 10 eV. HEAT is fully commissioned and is taking data continuously since September 2009. The status and prospects of HEAT are discussed and first (preliminary) data are presented.
29520771
Search for magnetic monopoles with the Soudan 2 detector.
A search for grand unified theory magnetic monopoles making highly ionizing tracks in argon gas has been conducted using the Soudan 2 nucleon decay detector. This underground detector is a large fine-grained tracking calorimeter comprised of long drift tubes read out by proportional wires. No monopole candidates were observed in data taken over almost three years, yielding an upper flux limit of 8.7{times}10{sup {minus}15} cm{sup {minus}2}s{sup {minus}1}sr{sup {minus}1} for monopole velocities of {beta}{gt}2{times}10{sup {minus}3}.
41110005
Ultrahigh energy cosmic ray composition from surface air shower and underground muon measurements at Soudan 2.
The Soudan 2 experiment has performed time-coincident cosmic ray air shower and underground muon measurements. Comparisons to Monte Carlo predictions show that such measurements can make statistically significant tests of the primary composition in the knee region of the cosmic ray spectrum. The results do not support any significant increase in the average primary mass with energy in the range of {similar_to}10{sup 4} TeV per nucleus. Some systematic uncertainties remain, however, particularly in the Monte Carlo modeling of the cosmic ray shower.
123571163
A classification of second‐order raising operators for Hamiltonians in two variables
We develop a group theoretic method based on results of Winternitz et al. to compute and classify all first‐ and second‐order raising and lowering operators admitted by Hamiltonians of the form H¯=−(1/2)Δ2+V(x,y). The key to our results, which generalize to higher dimensions, is a proof that H¯ admits a second‐order raising operator only if the Schrodinger equation separates in Cartesian, polar, or elliptic coordinates.
16171199
The Coulomb-oscillator relation on n-dimensional spheres and hyperboloids
We establish a relation between Coulomb and oscillator systems on n-dimensional spheres and hyperboloids for n≥2. We show that, as in Euclidean space, the quasiradial equation for the (n+1)-dimensional Coulomb problem coincides with the 2n-dimensional quasiradial oscillator equation on spheres and hyperboloids. Using the solution of the Schrödinger equation for the oscillator system, we construct the energy spectrum and wave functions for the Coulomb problem.
55017968
Series solutions for the Dirac equation in Kerr-Newman space-time
The Dirac equation is solved for an electron in a Kerr–Newman geometry using an adaptation of the procedure of Chandrasekhar. The corresponding eigenfunctions obtained can be represented as series of Jacobi polynomials. The spectrum of eigenvalues can be calculated using continued fraction techniques. Representations for the eigenvalues and eigenfunctions are obtained for various ranges of the parameters appearing in the Kerr–Newman metric. Some comments concerning the bag model of nucleons are made.
120256112
CLEBSCH--GORDAN COEFFICIENTS AND SPECIAL FUNCTION IDENTITIES. II. THE ROTATION AND LORENTZ GROUPS IN 3-SPACE.
It is shown that the construction of concrete models of Clebsch‐Gordan decompositions for tensor products of irreducible group representations leads to a wide variety of special function identities. In this paper the representation theory of the rotation and Lorentz groups in 3‐space is used to give elegant derivations of identities involving Languerre, Gegenbauer, hypergeometric, and generalized hypergeometric functions. Some of these identities may be new in this general form.
55946508
Fluorocarbon evaporative cooling developments for the ATLAS pixel and semiconductor tracking detectors
We report on the development of evaporative fluorocarbon cooling for the ATLAS Pixel and SemiConductor Tracker (SCT) detectors. Data are presented from cooling studies on representative prototype Pixel and SCT detector thermo-structures, using perfluoro-npropane (C3F8), -butane (C4F10), trifluoro-iodo-methane (CF3I) and custom C3F8/C4F10 mixtures. Thermophysical properties were calculated for custom mixtures. For most of the structures tested at full projected power dissipation, operation of silicon detector substrates at temperatures below –7oC (required for 10 year lifetime in the radiation environment of LHC) should be possible, albeit in some cases with increases in inner diameter (I.D.) of the coolant tubes from those of the present series of prototypes. Heat transfer coefficients in the range 2-5.103 Wm-2K-1 have been measured in a 3.6 mm I.D. heated tube dissipating 100 Watts close to the full equivalent power (~110 W) of a barrel SCT detector “stave” over a range of power dissipations and mass flows in the above fluids. Aspects of full-scale evaporative cooling circulator design for the ATLAS experiment are discussed, together with plans for future development.