120093834
Rigorous sum rules and bounds on pion-pion scattering amplitudes with positivity
We derive the complete set of crossing symmetric forward pion-pion amplitudes with non-negative absorptive parts obeying twice-subtracted dispersion relations. We give a method to eliminate subtraction constants for these amplitudes by making a simultaneous use of subtracted dispersion relations for the amplitude and its inverse, and unitarity. We thus deduce from axiomatic field theory (i) lower bounds on forward real parts in terms of physical forward amplitudes, (ii) lower bounds on S- and P-wave scattering lengths in terms of forward amplitudes in any part of the physical region, (iii) sum rules on scattering lengths in terms of physical forward amplitudes which provide a complete test of forward dispersion relations, (iv) upper bounds on scattering lengths in terms of total cross sections and (v) absolute sum rule inequalities on total and forward differential cross sections in terms of the pion mass alone which provide new tests of dispersion relations not involving scattering lengths.
117295648
REGGE POLES AND ASYMPTOTIC BEHAVIOR IN THE ANALYTIC CONTINUATION OF THE PION-NUCLEON SCATTERING AMPLITUDE
123264743
Rigorous sum rules and bounds on pion-pion scattering lengths
Abstract We deduce from axiomatic field theory rigorous sum rules, and upper and lower bounds on S-and P-wave ππ scattering lenghts in terms of physical region forward ππ amplitudes, and also absolute sum rule inequalities on those amplitudes involving pion mass alone.
35249306
Quantum violation of stochastic noncontextual hidden-variable theories.
We formulate stochastic noncontextual hidden-variable theories. In such theories the hidden state λ specifies not definite values, but expectation values A − (λ), ... of observables A, ... and noncontextuality means that A − (λ) is independent of which other commuting observables commuting with A are measured together with A. We show via Bell inequalities that such theories conflict with quantum theory and propose a two-photon experimental test. We also show that for a single particle of spin (2 n −1)/2, quantum violation of classical noncontextuality grows exponentially with n.
120223172
psi particles, SU(4), and anomalous currents
We propose assignment of the new ψ particles in an SU(4) symmetry scheme, incorporating SU(3) and a new additive quantum number, paracharge Z. Anomalous currents are introduced to account for the production and decays of these particles. Two more rather broad resonances at around 4.3 and 5.0 (±0.2) GeV are expected in the e + e - annihilation, one of which has recently been reported (at 4.15 GeV).
123580858
Unitarity upper bound on the absorptive parts of elastic scattering amplitudes
We derive a unitarity upper bound on the absorptive part A(s, t) of the elastic-scattering amplitude in the physical region. In the diffraction peak region the bound on A(s, t)/A(s, 0) is a function only of the parameter σ tot 2 (−t)/4πσ el . Assuming the diffraction scattering to be purely absorptive and spin independent we find the pp, pp, and π ± p data to lie a little below the theoretical upper bound. Further the experimental curve of X(t)/X(0) vs −4tX(0)/σ el , where X(t)≡dσ/dt, seems "universal."
123024852
Results Of A Scintillating Fiber Preshower Detector For Identifying Electrons Via Synchrotron Radiation
118226840
Flow effects in 84Kr induced collisions in emulsion at 0.95 GeV per nucleon

Abstract. Using emulsion detector the collective flow signals in inelastic interactions of 84Kr nuclei with Ag(Br) at 950 MeV/nucleon are studied. A transverse momentum analysis is performed to determine the reaction plane. The bounce-off of spectator fragments is observed. In azimuthal distributions relative to the reaction plane squeeze-out and side-splash of participants are seen.
120083760
Effect of N/Z in pre-scission neutron multiplicity for 16,18O+194,198Pt systems
This paper report the summary of the experimental results of pre-scission neutron multiplicities from four compound nuclei, namely 210,212,214,216 Rn, and statistical model analysis of the corresponding data. The compound nuclei 210,212,214,216 Rn having N/Z values as 1.441, 1.465, 1.488, 1.511 respectively are populated through the 16,18 O+ 194,198 Pt reactions at excitation energies of 50, 61, 71.7 and 79 MeV. The measured neutron multiplicities are further analyzed with the statistical model of nuclear decay where fission hindrance due to nuclear dissipation is considered. The N/Z dependence of the dissipation strength at lowest excitation energy of the compound nuclei suggests shell closure effects. However, such effects are not observed at higher excitations where the variation of the dissipation strength with N/Z does not show any specific trend. The variation of N/Z in fission time scale is also shown.
118562891
Constraints on Non-Commutative Physics Scale with Neutrino-Electron Scattering
Neutrino-electron scatterings ($\ensuremath{\nu}\ensuremath{-}e$) are purely leptonic processes with robust standard model predictions. Their measurements can therefore provide constraints to physics beyond the standard model. Noncommutative (NC) field theories modify space-time commutation relations, and allow neutrino electromagnetic couplings at the tree level. Their contribution to the neutrino-electron scattering cross section was derived. Constraints were placed on the NC scale parameter ${\ensuremath{\Lambda}}_{\mathrm{NC}}$ from $\ensuremath{\nu}\ensuremath{-}e$ experiments with reactor and accelerator neutrinos. The most stringent limit of ${\ensuremath{\Lambda}}_{\mathrm{NC}}g3.3\text{ }\text{ }\mathrm{TeV}$ at 95% confidence level improves over the direct bounds from collider experiments.
124164538
Low Energy Neutrino and Dark Matter Physics with sub‐keV Germanium Detectors
A TEXONO collaboration research program on low energy neutrino and dark matter physics is going on at the Kuo‐Sheng Neutrino Laboratory (KSNL). Collaboration main goals are to measure the neutrino‐nucleus coherent scattering cross section, neutrino magnetic moments, and the searches of WIMP dark matter. To achieve these goals various prototype detectors and their sub‐keV background are under study. A threshold of 220 eV was achieved with prototype detectors at the KSNL. New limits were set for WIMPs with mass between 3‐6 GeV. Data are being taken with a 500 g Point Contact Germanium detector, where a threshold of ∼350 eV was demonstrated. A 20 g ULEGe detector is taking data at CJPL in Sichuan, China.