R.S. Storey

A Heavy Water Detector to Resolve the Solar Neutrino Problem

Abstract The observation of the following three reactions: νed→ppe; νxe→νxe; and νxd→νxpn (where νx is any left- handed neutrino) in a heavy water Cerenkov detector which is being designed, allows the solar 8B ve flux, spectrum and direction to be measured. In addition, the total solar 8 Bν c neutrino flux, direction and integral spectrum, independent of neutrino flavor, may be determined to provide several independent methods to resolve the solar neutrino problem.

Scaling properties of charged particle multiplicity distributions in oxygen induced emulsion interactions at 14.6, 60 and 200 A GeV

Abstract The multiplicity distributions of shower particles (ns) are measured in inclusive inelastic oxygen emulsion interactions. Scaling is observed in the normalized variable ns/〈ns〉 for 14.6, 60 and 200 AGeV. The dependence of 〈ns〉 on the charge flow in the forward direction (QZD) and the distribution of the number of participating projectile protons is examined. The normalized multiplicities as a function of QZD seem also to be independent of incident energies. A comparison with the Lund model Fritiof yields satisfactory agreement.

Determination of the attenuation coefficients of visible and ultraviolet radiation in heavy water.

A long-path-length transmission cell has been used to measure the attenuation coefficients of purified H2O and D2O at various wavelengths between 250 and 580 nm. The principles governing the procedures and corrections for various sources of light attenuation in the transmission cell components are discussed. Detailed chemical histories of the H2O and D2O samples are given. The measured attenuation coefficients of H2O are lower than those of many previous determinations and, where comparable, are close to the record low values of Quickenden and Irvin [ J. Chem. Phys.72, 4416 ( 1980)]. The measured attenuation coefficients of D2O are the lowest yet achieved and range from 32 × 10−4 cm−1 at 254 nm down to 1.1 × 10−4 cm−1 at 578 nm, attesting to the low level of impurities in our D2O. These results on light transmission in D2O indicate that a large 1000-Mg heavy water Cherenkov detector constructed for the purpose of neutrino detection is not limited by the attenuation length of radiation in the D2O.

Rapidity densities and their fluctuations in central 200 A GeV 32S interactions with Au and Ag, Br nuclei EMU01 collaboration

The pseudo-rapidity density distributions of shower particles (n s ) are measured in central inelastic S + Au and S + Ag,Br inter-actions. The extracted maximum energy densities, while being higher for Au than for Ag.Br interactions, were found to be similar to those obtained for oxygen emulsion interactions. The correlation between rapidity density and shower particle multiplicity shows a small deviation from the Lund Model Fritiof for the highest energy densities in S + Au interactions, whereas the bulk of the data yields satisfactory agreement.

Multiplicities and rapidity densities in 200 A GeV 16O interactions with emulsion nuclei

Abstract We report on an experiment in which emulsion chambers were exposed to a beam of 200 A GeV 16 O at the CERN SPS. Pseudo-rapidity distributions are measured with high precision. Pseudo-rapidity densities of 140 particles per unit rapidity corresponding to an energy density of about 3 GeV/fm3 are observed. Pseudo-rapidity density distributions and fluctuations are found to satisfactorily agree with the Lund Monte Carlo model Fritiof, although new and unknown sources for fluctuations might still be present.

Lifetimes of 44Ti Levels

Abstract Lifetimes in 44 Ti have been measured by the attenuated Doppler shift following α-capture in 40 Ca. targets. Mean lifetimes for the 1083 keV (2 + 1 ), the 2454 keV (4 + 1 ), the 2531 keV (2 + 2 ), the 2886 keV (2 + 3 ) and the 3415 keV states of 44 Ti are respectively 4.5 ± 1.1, 0.60 ± 0.11, 1.42 ± 0.20, 0.42 ± 0.14 and 0.70 ± 0.11 ps. The lifetimes of the 1904 keV (0 + 2 ) and 3176 keV states are greater than 0.7 and 3.0 ps, respectively. The level energies and experimental B (E2) values support the vibrational model as a first approximation for 44 Ti. On the other hand the strong 2 + 2 → 0 + 2 transition (24 ± 6 W.u.) suggests the beginning of a rotational band based on a deformed panicle-hole configuration.

Electromagnetic decay of first and second T = 32 states in 19F

Abstract The two lowest T = 3 2 states in 19 F have been found as strong isolated resonances in the 15 N (α, γ) 19 F reaction. Some significant discrepancies are found between the measured transition strengths and those calculated from shell-model wave functions.

A search for non-statistical particle density fluctuations in 16O + Ag(Br) and 32S + Au interactions at 200 A GeV

Abstract Fluctuations in particle densities of non-statistical origin are studied in central 16 O+Ag(Br) and 32 S+Au interactions at 200 A GeV. Non-statistical fluctuations in the 32 S-induced interactions seem to enhance the local particle densities, and suggest the presence of intermittancy. The fluctuations are found to be accompanied by a clustering tendency also in the azimuthal plane. A new method for the study of azimuthal correlations is proposed.

A study of 28Si(α, γ)32S resonances below Eα = 3.83 MeV

Abstract The γ-decays of eleven resonances in the 28 Si(α,γ) 32 S reaction below E α = 3.83 MeV have been studied using a large Ge(Li) detector. Results for branching ratios differ considerably from previous NaI work. The previous discrepancy in radiative strengths for the 2.61 MeV resonance is explained by this data. The strengths of the first five resonances at E α = 1.77, 1.99, 2.19, 2.37 and 2.42 MeV appear to be (39 ± 13)% lower than previously reported. Spin-parities of l − , 2 + and 2 + have been assigned to the levels at 8.50, 8.69 and 8.86 MeV respectively. The radiative width of the E p = 1.467 MeV, J π = 3 − resonance in the 31 P(p,γ) 32 S reaction has also been measured.

The mass and energy levels of 44Ti

Abstract Energy levels of the self-conjugate nucleus 44Ti have been studied with the 40 Ca (α, γ) 44 Ti reaction. A shell-model calculation of levels in 44Ti and 44Sc has been performed for comparison purposes.