background: the aim of this work was to establish how well gel dosimeters performed, as substitutes for brain tissue compared with standard phantom materials such as water, polymethyl-methacrylate (or pmma), a150 plastic and te- liquid phantom material for dosimetry of neutron beams in boron neutron capture therapy. materials and methods: thermal neutron fluence, photon dose and epithermal neut...

The spectrum of neutrons emitted after the B-decay of ~Li has been measured with a large time-of-flight array. The spectrum exhibits six peaks corresponding to neutron emission from known states in the l lBe daughter nucleus. The measured branching ratios indicate significant feeding to states over a broad energy range. The energies and parities of the states are in very good agreement with the...

We here propose a two-step model for gamma-ray bursts (GRBs) associated with supernovae. In the first step, the core collapse of a star with mass ≥ 19M⊙ leads to a massive neutron star and a normal supernova, and subsequently hypercritical accretion of the neutron star from the supernova ejecta may give rise to a jet through neutrino annihilation along the stellar rotation axis. However, becaus...

We present a numerical study of the hydrodynamics in the final stages of inspiral in a black hole–neutron star binary, when the separation becomes comparable to the stellar radius. We use a Newtonian three–dimensional Smooth Particle Hydrodynamics (SPH) code, and model the neutron star with a soft (Γ = 5/3) polytropic equation of state and the black hole as a Newtonian point mass which accretes...

We present a numerical study of the hydrodynamics in the final stages of inspiral of a black hole–neutron star binary, when the binary separation becomes comparable to the stellar radius. We use a Newtonian three–dimensional Smooth Particle Hydrodynamics (SPH) code, and model the neutron star with a soft (adiabatic index Γ = 5/3) polytropic equation of state and the black hole as a Newtonian po...

The standard unbroken electroweak theory is known to erase the baryon number. The baryon number symmetry can be restored in the core of a neutron star if its density diverges via gravitational instability due to a binary merger event. We argue that for certain double Higgs models with discrete symmetries this process may result in an expanding self-sustained burning front that would convert the...

For passive scattering proton therapy systems, neutron contamination is the main concern both from an occupational and patient safety perspective. The Mevion S250 compact proton therapy system is the first of its kind, offering an in-room cyclotron design which prompts more concern for shielding assessment. The purpose of this study was to accomplish an in-depth evaluation of both the shielding...

background: the poly-allyl diglycol carbonate (padc) detector is of particular interest for development of a fast neutron dosimeter. fast neutrons interact with the constituents of the cr-39 detector and produce h, c and o recoils, as well as (n, α) reaction. these neutron- induced charged particles contribute towards the response of cr-39 detectors. material and methods: electrochemical etchin...

A portable assembly containing a vertical-bend dipole magnet has been designed and installed immediately down-beam of the Compton electron-laser interaction chamber on beamline 1 of the Accelerator Test Facility (ATF) at Brookhaven National Laboratory (BNL). The watercooled magnet designed with field strength of up to 0.7 Tesla will be used as a spectrometer in the Thompson scattering and vacuu...