A two-phase argon avalanche detector operated in a single electron counting mode
The performance of a two-phase Ar avalanche detector in a single electron counting mode was studied, with regard to potential application in coherent neutrino-nucleus scattering and dark matter search experiments. The detector comprised a 1 cm thick liquid Ar layer and a triple-GEM multiplier operated in the saturated vapour above the liquid phase. Successful operation of the detector in single electron counting mode, in the gain range from 6000 to 40,000, has for the first time been demonstrated.

title: The ZEPLIN-III dark matter detector: Performance study using an end-to-end simulation tool
abstract: We present results from a GEANT4-based Monte Carlo tool for end-to-end simulations of the ZEPLIN-III dark matter experiment. ZEPLIN-III is a two-phase detector which measures both the scintillation light and the ionisation charge generated in liquid xenon by interacting particles and radiation. The software models the instrument response to radioactive backgrounds and calibration sources, including the generation, ray-tracing and detection of the primary and secondary scintillations in liquid and gaseous xenon, and subsequent processing by data acquisition electronics. A flexible user interface allows easy modification of detector parameters at run time. Realistic datasets can be produced to help with data analysis, an example of which is the position reconstruction algorithm developed from simulated data. We present a range of simulation results confirming the original design sensitivity of a few times 10−8 pb to the WIMP-nucleon cross-section.

title: The potential of liquid xenon for WIMP search: the ZEPLIN diagnostic array
abstract: A Liquid Xenon based WIMP detector diagnostic array is currently developed by the UKDMC with the help of international collaborators. After a brief reminder on the detection principle in Liquid Xenon, the individual detectors will be described. ZEPLIN I, a detector with a 4 kg fiducial mass with a background discrimination based on Pulse Shape Analysis, is already underground and starting operation. Two setups with improved background discrimination tools (as the ionisation is also recorded) are designed and scheduled to move underground in the second half of 2001. Both of them, ZEPLIN II and ZEPLIN III, are predicted to be sensitive to rate of 0.1–0.01 events/kg/day within 2 years of data taking. Furthermore, new ideas for lower background readout devices are studied, in order to avoid the use of PhotoMultiplier Tubes (PMTs).

title: Muon-induced background in the EDELWEISS dark matter search
abstract: A dedicated analysis of the muon-induced background in the EDELWEISS dark matter search has been performed on a data set acquired in 2009 and 2010. The total muon flux underground in the Laboratoire Souterrain de Modane (LSM) was measured to be Φ μ = ( 5.4 ± 0.2 - 0.9 + 0.5 )  muons/m 2 /d. The modular design of the μ -veto system allows the reconstruction of the muon trajectory and hence the determination of the angular dependent muon flux in LSM. The results are in good agreement with both MC simulations and earlier measurements. Synchronization of the μ -veto system with the phonon and ionization signals of the Ge detector array allowed identification of muon-induced events. Rates for all muon-induced events Γ μ = ( 0.172 ± 0.012 ) evts / ( kg d ) and of WIMP-like events Γ μ – n = 0.008 - 0.004 + 0.005 evts / ( kg d ) were extracted. After vetoing, the remaining rate of accepted muon-induced neutrons in the EDELWEISS-II dark matter search was determined to be Γ irred μ – n 6 · 10 - 4 evts / ( kg d ) at 90% C.L. Based on these results, the muon-induced background expectation for an anticipated exposure of 3000 kg d for EDELWEISS-III is N 3000 kg d μ – n 0.6 events.

title: Progress report from the UK Dark Matter search at Boulby Mine
abstract: The UK Dark Matter Collaboration is currently running a series of scintillation devices at the Boulby mine in North Yorkshire to search for the neutralino, the hypothetical WIMP solution to the dark matter problem. Results of the current NaI(T1) detector array will be discussed, illustrating a population of events of unknown origin. Diagnostic tests performed to investigate the origin of these anomalous events will be outlined, including alpha, beta and neutron calibrations.

title: Particle polarization in inclusive reactions

title: Conformal covariant description of mesons and baryons in composite superconformal string model
abstract: Operator nucleon vertices are constructed in composite superconformal string model. Splitting of baryon Regge trajectories with the same quantum numbers but with opposite parity is provided by inclusion of special two-dimensional field to be carried spin-parity quantity on the basic two-dimensional surface. Then conservation of cyclic symmetry of hadron string amplitudes and necessary duality properties requires nucleon vertices with separation of spinor components of different chirality.

title: Nonplanar dual model with arbitrary intercept $alpha$(0)

title: Production of high-energy muons in extensive air showers from primary el rays
abstract: The primary mechanism for the production of high-energy muons (E/sub / > 5 TeV) in extensive air showers from primary el rays is the production of muon pairs by shower photons in the field of a nucleus.

title: Heavy states of hadron string as weak interacting massive particles for Dark Matter
abstract: Massive states (of order 10 Gev and more) of hadron string (with scale 1 Gev) can have very small coupling constants with usual baryons of the Universe. Corresponding mean times for them are found to be order and even more than the age of the Universe. They are proposed as possible candidates for weak interacting massive particles (WIMP) of Dark Matter.

title: Interaction amplitudes of hadrons treated as composite superconformal strings