Search results for "SPECTRA"
showing 10 items of 3542 documents
Gamow–Teller beta decays of the odd-mass neighbors of the solar-neutrino detector 127I
2002
Abstract Calculations of the energy spectra and the log ft values of Gamow–Teller beta transitions of neutron-odd and proton-odd nuclei close to the solar-neutrino detector 127I are performed using the microscopic quasiparticle–phonon model. The information obtained from the beta transition strengths is valuable in solar-neutrino detection and dark matter search both in present and future large-scale experiments. Realistic interactions within a realistic single-particle valence space were used in the calculations. The overall correspondence in terms of the excitation spectra and the log ft values between theory and experiments can be regarded as quite good when considering the completely mi…
Strange quark mass from τ decays
2001
7 páginas, 3 figuras, 3 tablas.-- Comunicación presentada en el 6º International Workshop on Tau Lepton Physics (Tau00) celebrado del 18 al 21 de Septiembre de 2000 en Victoria (Canada).
Comparison of T[sub z] = ±1→0 GT Transitions
2010
Gamow‐Teller (GT) transitions can be studied in both β‐decay and charge exchange(CE) reactions. If isospin is a good quantum number, then the Tz = −1→0 and Tz = +1→0 GT mirror transitions, are identical. Therefore, a comparison of the results from studies of β decay and CE should shed light on this assumption. Accordingly we have studied the β decay of the Tz = −1 fp‐shell nuclei, 54Ni, 50Fe, 46Cr, and 42Ti, produced in fragmentation and we have compared our results with the spectra from (3He, t) measurements on the mirror Tz = +1 target nuclei studied in high resolution at RCNP, Osaka. The β‐decay experiments were performed as part of the STOPPED beam RISING campaign at GSI.
Statistical decay of hyperfragments
2011
Combining the unique features of the hypernuclear electro-production mechanism and the high precision in magnetic spectroscopy, the proposed E-08-012 experiment at Jefferson Lab, Virginia, and the scheduled hypernuclear experiment at MAMI, Germany, focus on the high-resolution spectroscopy of weak two-body decay pions from hypernuclei. These experiments will provide insight on a wide range of light hypernuclei via the production of hyperfragments from 9 Be, 6,7 Li and 12 C targets. In the present work we explore the production of Λ-hypernuclei following the micro-canonical break-up of an initially excited hypernucleus which is created by the electro/photo-production reaction. Finally the mo…
Positron-Electron Angular Correlations in Heavy Ion Collisions
1987
Recent measurements of positrons in coincidence with electrons emitted in U+Th collisions near the Coulomb barrier show sharp line structures in the sum and difference energy spectra of the two leptons (ref. 1). A possible method to clarify the origin of these lines is to study the angular correlation of the leptons. In this short contribution we want to report on a positron-electron coincidence test measurement performed with the TORI spectrometer. This apparatus offers the possibility to measure positrons in coincidence with electrons emitted into the same and opposite hemisphere as well.
A time-of-flight facility for the measurement of electron-induced neutron spectra
1974
Abstract A time-of-flight facility is constructed to investigate photoneutrons in the energy range 5 MeV ≤ En ≤ 200 MeV. Photoneutrons are detected simultaneously at four angles (40.2°, 90°, 113.5°, 142.2°). The overall time resolution varies from 0.282 ns/m to 0.358 ns/m, depending on the different flight paths (18.56 m to 11.40 m). As a first check the facility is used to measure the ratio of the number of virtual photons to real photons via the photodisintegration of 2H. The measured values agree with the calculated photon spectra.
New Features in the Systematics of Low‐Spin States in Even 106‐120Cd
1991
Low‐spin states in even 106‐112Cd and 116Cd were investigated by in‐beam and off‐beam γ‐ray and conversion‐electron spectroscopy. New spin assignments and decay branching ratios for the levels in 106Cd,108Cd,110Cd and 112Cd were obtained. From the new systematical data for the even 106‐120Cd, it is inferred that two sets of low‐lying 0+ states cross between 114Cd and 116Cd. One of these sets appears to have features of both intruder and two‐quadrupole‐phonon states.
Low-energy (anti)neutrino physics with Borexino: Neutrinos from the primary proton-proton fusion process in the Sun
2014
The Sun is fueled by a series of nuclear reactions that produce the energy that makes it shine. The primary reaction is the fusion of two protons into a deuteron, a positron and a neutrino. These neutrinos constitute the vast majority of neutrinos reaching Earth, providing us with key information about what goes on at the core of our star. Several experiments have now confirmed the observation of neutrino oscillations by detecting neutrinos from secondary nuclear processes in the Sun; this is the first direct spectral measurement of the neutrinos from the keystone proton-proton fusion. This observation is a crucial step towards the completion of the spectroscopy of pp-chain neutrinos, as we…
Structure ofIn112nucleus
1988
The \ensuremath{\gamma}-ray spectra of the $^{112}\mathrm{Cd}$(p,n\ensuremath{\gamma}${)}^{112}$In and $^{109}\mathrm{Ag}$(\ensuremath{\alpha},n\ensuremath{\gamma}${)}^{112}$In reactions were measured with Ge(Li) spectrometers for bombarding energies of 4.8 MeV protons and 17.1 MeV \ensuremath{\alpha} particles. The energies and relative intensities of 79 $^{112}\mathrm{In}$ \ensuremath{\gamma}-ray transitions have been determined. The electron spectra were measured with combined magnet plus Si(Li) as well as superconducting magnetic lens plus Si(Li) spectrometers. Internal conversion coefficients of 40 $^{112}\mathrm{In}$ transitions have been determined, and the level scheme of $^{112}\ma…
Nuclear charge radii of the even sulphur isotopesS32,S34, andS36and ofP31using muonic atoms
1985
Energies of muonic x rays of the Lyman series of the even sulphur isotopes /sup 32/S, /sup 34/S, and /sup 36/S and of natural phosphorus have been determined with absolute precisions up to 23 parts/10/sup 6/. Equivalent Barrett charge radii R/sub k/,..cap alpha.. have been deduced. Their differences between the sulphur isotopes amount to ..delta..R/sub k/,..cap alpha..( /sup 34/S- /sup 32/ S) = 29.7(1.4) am and ..delta..R/sub k/,..cap alpha..( /sup 36/S- /sup 34/ S) = 18.7(1.5) am. Combining these results with recent elastic electron scattering data, we obtain in a model-independent way ..delta../sup 1/2/( /sup 34/S- /sup 3/ 2S) = 23.1(1.2) am and ..delta../sup 1/2/( /sup 36/S- /sup 3/ 4S) …