Search results for "beam"
showing 10 items of 2126 documents
The new nuclide225U
1989
In the bombardment of a 270μg/cm 2 180Hf target with48 Ca projectiles at a primary beam energy of E/A=4.24 MeV/u the new nuclide225U was produced. The experiment was performed at the velocity filter SHIP. 225U was found to decay by α emission with Eα=(7880 ±20) keV (≈90%), (7830±20) keV (≈10%) and has a half-life ofT 1/2=(80 −20 +40 ms).
Total cross section measurement for the three double pion photoproduction channels on the proton
1995
Abstract The total cross sections for the three γp → Nππ reactions have been measured for photon energies from 400 to 800 MeV. The γ p → p π 0 π 0 and γ p → n π + π 0 cross sections have never been measured before while the γ p → p π + π − results are much improved compared to earlier data. These measurements were performed with the large acceptance hadronic detector DAPHNE, at the tagged photon beam facility of the MAMI microtron in Mainz.
In-beam electron spectrometer used in conjunction with a gas-filled recoil separator
2004
The conversion-electron spectrometer SACRED has been redesigned for use in conjunction with the RITU gas-filled recoil separator. The system allows in-beam recoil-decay-tagging (RDT) measurements of internal conversion electrons. The performance of the system using standard sources and in-beam is described.
Beamline for low-energy transport of highly charged ions at HITRAP
2015
Abstract A beamline for transport of highly charged ions with energies as low as a few keV/charge has been constructed and commissioned at GSI. Complementary to the existing infrastructure of the HITRAP facility for deceleration of highly charged ions from the GSI accelerator, the new beamline connects the HITRAP ion decelerator and an EBIT with the associated experimental setups. Therefore, the facility can now transport the decelerated heavy highly charged ions to the experiments or supply them offline with medium-heavy highly charged ions from the EBIT, both at energies as low as a few keV/charge. Here we present the design of the 20 m long beamline with the corresponding beam instrument…
Neutrino oscillation physics with a higher-γ β-beam
2004
The precision measurement and discovery potential of a neutrino factory based on boosted radioactive ions in a storage ring (“β-beam”) is re-examined. In contrast with past designs, which assume ion γ factors of ∼100 and baselines of L=130 km, we emphasize the advantages of boosting the ions to higher γ and increasing the baseline proportionally. In particular, we consider a “medium-γ” scenario (γ∼500, L∼730 km) and a “high-γ” scenario (γ∼2000, L∼3000 km). The increase in statistics, which grow linearly with the average beam energy, the ability to exploit the energy dependence of the signal and the sizable matter effects at this longer baseline all increase the discovery potential of such a…
New results on hyperon decays from NA48
2001
In 1999 the NA48 experiment at CERN had two short data taking periods (8h and 40h) with a high intensity KS beam. Together with the KS mesons a large number of neutral hyperons, e.g. Λ and Ξ0, are produced. During these periods a large sample of Ξ0 decays was collected. About 115,000 events of the decay mode Ξ0 → Λπ0, about 500 of Ξ0 → Λγ, about 400 of Ξ0 → Σ0γ and about 60 events of Ξ0 → Σ+ e have been reconstructed. The status of the analyses of the above decay modes is presented.
Recent results from experiments at MAMI
2012
Abstract The Mainz Microtron MAMI is an ideal tool for studying the structure of strongly interacting systems with an electromagnetic probe. With the new HDSM accelerator stage of MAMI C, a continuous-wave electron beam with an energy of up to 1604 MeV and excellent beam quality is available for precision experiments. In addition, polarisation degrees of freedom can be exploited with polarised beams and either polarised targets or recoil polarimetry. This paper presents selected results of the A1, A2, and A4 collaborations.
In-beam studies of203, 205Bi and shell-model features of odd-a bismuth isotopes
1982
States in203, 205Bi are populated using the reaction203, 205Tl(3He,3n). Theπi13/2 single-proton states and all the members of thev(21+)⊗π h9/2 quintuplet are identified in both nuclei. The half-lives of the isomericJπ=21/2+ states in both isotopes are measured and found to be 90±7 ns and 100±6 ns, and from these values suggestions for the half-lives of the previously reportedJπ=25/2+ isomers are made. The structures of the multiplets of the formv(Pb)⊗π h9/2 are calculated in the framework of the shell model and it is shown that the main features can be derived from theπ−v−1 effective interaction. The wave functions of the 41+ and 40+ states in202, 204pb are deduced indirectly from the calcu…
Correlated e+ e− peaks observed in heavy-ion collisions
1990
Abstract Three very narrow e + e − sum-energy peaks around 610, 750, and 810 keV have been observed in U+Th as well as in U+Ta collisions at beam energies around the Coulomb barrier. As no processes involving conventional atomic and nuclear physics were found to describe their origin, the data were in particular confronted with the hypothesis that the lines are due to the two-body decay of neutral objects in an e + e + pair. Although the 810 keV sum-energy line observed in U+Th is consistent with the prompt two-body e + e − decay of a neutral object if created nearly at rest in the heavy-ion center-of-mass system, the other lines require at least a considerably more complicated scenario if …
In-beam study of 102In, 104In and 106In
1995
Proton-rich odd-odd In isotopes have been investigated by in-beam spectroscopic methods using the NORDBALL detector array. A Ni-58 beam with an energy of 270 MeV was used to bombard a Fe-54 target. ...