Sqrt{shat}_{min} resurrected

We discuss the use of the variable sqrt{shat}_{min}, which has been proposed in order to measure the hard scale of a multi parton final state event using inclusive quantities only, on a SUSY data sample for a 14 TeV LHC. In its original version, where this variable was proposed on calorimeter level, the direct correlation to the hard scattering scale does not survive when effects from soft physics are taken into account. We here show that when using reconstructed objects instead of calorimeter energy and momenta as input, we manage to actually recover this correlation for the parameter point considered here. We furthermore discuss the effect of including W + jets and t tbar+jets background in our analysis and the use of sqrt{shat}_{min} for the suppression of SM induced background in new physics searches.Comment: 23 pages, 9 figures; v2: 1 figure, several subsections and references as well as new author affiliation added. Corresponds to published versio

Scintillation efficiency of liquid xenon for nuclear recoils with the energy down to 5 keV

The scintillation efficiency of liquid xenon for nuclear recoils has been measured to be nearly constant in the recoil energy range from 140 keV down to 5 keV. The average ratio of the efficiency for recoils to that for gamma-rays is found to be 0.19+-0.02.Comment: 13 pages, 5 figure

Supersymmetric particle mass measurement with the boost-corrected contransverse mass

A modification to the contransverse mass (MCT) technique for measuring the masses of pair-produced semi-invisibly decaying heavy particles is proposed in which MCT is corrected for non-zero boosts of the centre-of-momentum (CoM) frame of the heavy states in the laboratory transverse plane. Lack of knowledge of the mass of the CoM frame prevents exact correction for this boost, however it is shown that a conservative correction can nevertheless be derived which always generates an MCT value which is less than or equal to the true value of MCT in the CoM frame. The new technique is demonstrated with case studies of mass measurement with fully leptonic ttbar events and with SUSY events possessing a similar final state.Comment: 33 pages, 33 .eps figures, JHEP3 styl

Directional detection as a strategy to discover Galactic Dark Matter

Directional detection of Galactic Dark Matter is a promising search strategy for discriminating genuine WIMP events from background ones. Technical progress on gaseous detectors and read-outs has permitted the design and construction of competitive experiments. However, to take full advantage of this powerful detection method, one need to be able to extract information from an observed recoil map to identify a WIMP signal. We present a comprehensive formalism, using a map-based likelihood method allowing to recover the main incoming direction of the signal and its significance, thus proving its galactic origin. This is a blind analysis intended to be used on any directional data. Constraints are deduced in the ($\sigma_n, m_\chi$) plane and systematic studies are presented in order to show that, using this analysis tool, unambiguous dark matter detection can be achieved on a large range of exposures and background levels.Comment: 20 pages, 5 figures Final version to appear in Phys. Lett.

Bone mineral content after renal transplantation

Forearm bone mineral content (BMC), as evaluated by photonabsorption densitometry, was measured in 28 cadaver kidney donor recipients who entered the study 8 weeks postoperatively and were followed up for 18 months. BMC decreased signifiantly (p<0.05) but marginally in placebo-treated patients (n=14) (initial BMC 1.09±0.25 g/cm; final BMC 1.05±0.24). Fourteen patients were prophylactically given 1,25(OH)2vitamin D3 in a dose which avoided hypercalcemia and hypercalciuria (sim0.25 µg/day); under 1,25(OH)2 vitamin D3 prophylaxis a significant decrease of forearm BMC was observed no longer (initial BMC 0.94±0.21 g/cm; final BMC 0.95±0.21), but the difference between placebo and 1,25(OH)2 vitamin D3 narrowly missed statistical significance (p=0.066). It is concluded that the decrease of forearm BMC is negligible in transplant recipients with low steroid regimens. The data suggest a trend for prophylaxis with 1,25(OH)2 vitamin D3 to slightly ameliorate forearm (cortical) BMC loss

Constraining Dark Matter in the MSSM at the LHC

In the event that R-Parity conserving supersymmetry (SUSY) is discovered at the LHC, a key issue which will need to be addressed will be the consistency of that signal with astrophysical and non-accelerator constraints on SUSY Dark Matter. This issue is studied for the SPA benchmark model based on measurements of end-points and thresholds in the invariant mass spectra of various combinations of leptons and jets. These measurements are used to constrain the soft SUSY breaking parameters at the electroweak scale in a general MSSM model. Based on these constraints, we assess the accuracy with which the Dark Matter relic density can be measured.Comment: 21 pages, 12 figure

Limits on spin-dependent WIMP-nucleon cross-sections from the first ZEPLIN-II data

The first underground data run of the ZEPLIN-II experiment has set a limit on the nuclear recoil rate in the two-phase xenon detector for direct dark matter searches. In this paper the results from this run are converted into the limits on spin-dependent WIMP-proton and WIMP-neutron cross-sections. The minimum of the curve for WIMP-neutron cross-section corresponds to 0.07 pb at a WIMP mass of around 65 GeV.Comment: 12 pages, 2 figures, to be published in Physics Letters

Nuclear spin structure in dark matter search: The finite momentum transfer limit

Spin-dependent elastic scattering of weakly interacting massive dark matter particles (WIMP) off nuclei is reviewed. All available, within different nuclear models, structure functions S(q) for finite momentum transfer (q>0) are presented. These functions describe the recoil energy dependence of the differential event rate due to the spin-dependent WIMP-nucleon interactions. This paper, together with the previous paper ``Nuclear spin structure in dark matter search: The zero momentum transfer limit'', completes our review of the nuclear spin structure calculations involved in the problem of direct dark matter search.Comment: 39 pages, 12 figures, a review in revtex

Why honey is effective as a medicine. 1. Its use in modern medicine

Honey has been used as a medicine for thousands of years and its curative properties are well documented. However, modern medicine turned its back on honey and it is only now, with the advent of multi-resistant bacteria, that the antibiotic properties of honey are being rediscovered