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Title: Studies on exotic nuclei by proton-induced direct reaction at GSI and FAIR

Abstract

The proton-induced direct reactions like elastic, quasi-elastic scattering and knock-out at intermediate energies and inverse kinematics are the most powerful classical methods for obtaining spectroscopic information on the structure of unstable exotic nuclei. Few elastic scattering experiments performed at GSI with the gaseous and liquid hydrogen targets provided the most precise data on a nuclear matter distribution and a halo-core structure of the neutron-rich He and Li isotopes. The measured differential cross sections have been also used for probing density distributions as predicted by various microscopic theories. The comparison of the data with the latest calculations will be shown. The description of the recent experiment with proton-rich 8B and neutron-rich Be isotopes is presented.The experimental conditions at the future facility FAIR will provide unique opportunities for nuclear structure studies on nuclei far off stability, and will allow to reach new regions in the chart of nuclides of high interest for nuclear structure and astrophysics. In particular, predicted luminosity will allow for the investigation of direct reactions with stored and cooled radioactive beams at internal H, He, etc. targets of the storage ring NESR. This technique enables high resolution measurements down to very low momentum transfer and provides a gain inmore » luminosity from accumulation and recirculation of the radioactive beams. In order to explore the experimental conditions for measurements planned at EXL/FAIR setup, a first attempt exploring experimentally the feasibility of its concept has been recently made. A detector setup was installed at the ESR storage ring at GSI, Darmstadt. A 136Xe beam was interacting to an internal hydrogen gas-jet target. The detector setup had all the basic ingredients as foreseen by EXL collaboration. A set of scattering reactions has been studied and the overall performance of the setup demonstrated the feasibility of the EXL experimental approach.« less

Authors:
 [1];  [2]
  1. Gesellschaft fuer Schwerionenforschung, D-64291 Darmstadt (Germany)
  2. (Germany)
Publication Date:
OSTI Identifier:
21056736
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 891; Journal Issue: 1; Conference: 6. Symposium on nuclear physics, Tours (France), 5-8 Sep 2006; Other Information: DOI: 10.1063/1.2713514; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; BERYLLIUM ISOTOPES; BORON 8; COMPARATIVE EVALUATIONS; DIFFERENTIAL CROSS SECTIONS; DISTRIBUTION; ELASTIC SCATTERING; ESR STORAGE RING; KNOCK-OUT REACTIONS; LITHIUM ISOTOPES; MOMENTUM TRANSFER; NEUTRONS; NUCLEAR MATTER; NUCLEAR STRUCTURE; PROTON REACTIONS; PROTON-NUCLEON INTERACTIONS; PROTONS; QUASI-ELASTIC SCATTERING; SPECTROSCOPIC FACTORS; XENON 136

Citation Formats

Kiselev, O. A., and Institut fuer Kernchemie, Johannes Gutenberg Universitaet Mainz, D-55128 Mainz. Studies on exotic nuclei by proton-induced direct reaction at GSI and FAIR. United States: N. p., 2007. Web. doi:10.1063/1.2713514.
Kiselev, O. A., & Institut fuer Kernchemie, Johannes Gutenberg Universitaet Mainz, D-55128 Mainz. Studies on exotic nuclei by proton-induced direct reaction at GSI and FAIR. United States. doi:10.1063/1.2713514.
Kiselev, O. A., and Institut fuer Kernchemie, Johannes Gutenberg Universitaet Mainz, D-55128 Mainz. Mon . "Studies on exotic nuclei by proton-induced direct reaction at GSI and FAIR". United States. doi:10.1063/1.2713514.
@article{osti_21056736,
title = {Studies on exotic nuclei by proton-induced direct reaction at GSI and FAIR},
author = {Kiselev, O. A. and Institut fuer Kernchemie, Johannes Gutenberg Universitaet Mainz, D-55128 Mainz},
abstractNote = {The proton-induced direct reactions like elastic, quasi-elastic scattering and knock-out at intermediate energies and inverse kinematics are the most powerful classical methods for obtaining spectroscopic information on the structure of unstable exotic nuclei. Few elastic scattering experiments performed at GSI with the gaseous and liquid hydrogen targets provided the most precise data on a nuclear matter distribution and a halo-core structure of the neutron-rich He and Li isotopes. The measured differential cross sections have been also used for probing density distributions as predicted by various microscopic theories. The comparison of the data with the latest calculations will be shown. The description of the recent experiment with proton-rich 8B and neutron-rich Be isotopes is presented.The experimental conditions at the future facility FAIR will provide unique opportunities for nuclear structure studies on nuclei far off stability, and will allow to reach new regions in the chart of nuclides of high interest for nuclear structure and astrophysics. In particular, predicted luminosity will allow for the investigation of direct reactions with stored and cooled radioactive beams at internal H, He, etc. targets of the storage ring NESR. This technique enables high resolution measurements down to very low momentum transfer and provides a gain in luminosity from accumulation and recirculation of the radioactive beams. In order to explore the experimental conditions for measurements planned at EXL/FAIR setup, a first attempt exploring experimentally the feasibility of its concept has been recently made. A detector setup was installed at the ESR storage ring at GSI, Darmstadt. A 136Xe beam was interacting to an internal hydrogen gas-jet target. The detector setup had all the basic ingredients as foreseen by EXL collaboration. A set of scattering reactions has been studied and the overall performance of the setup demonstrated the feasibility of the EXL experimental approach.},
doi = {10.1063/1.2713514},
journal = {AIP Conference Proceedings},
number = 1,
volume = 891,
place = {United States},
year = {Mon Feb 26 00:00:00 EST 2007},
month = {Mon Feb 26 00:00:00 EST 2007}
}
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  • High-precision mass measurements of proton-rich isotopes in the range of 60{le}Z{le}84 were performed using the novel technique of Schottky spectrometry. Projectile fragments produced by {sup 209}Bi ions at 930{ital A} MeV were separated with the magnetic spectrometer FRS and stored and cooled in the experimental storage ring (ESR). A typical mass resolving power of 350000 and a precision of 100keV were achieved in the region A{approx}200 . Masses of members of {alpha} chains linked by precise Q{sub {alpha}} values but not yet connected to the known masses were determined. In this way it is concluded that {sup 201}Fr and {supmore » 197}At are proton unbound. {copyright} {ital 1997} {ital The American Physical Society}« less