The differential cross sections for small-angle proton elastic scattering on the
6,8,9,11Li nuclei at energies near 700 MeV/nucleon were measured in inverse kinematics using secondary nuclear beams ...at GSI Darmstadt. The hydrogen-filled ionization chamber IKAR was employed as target and recoil proton detector. For determining the nuclear matter radii and radial matter distributions, the measured cross sections have been analysed with the aid of the Glauber multiple-scattering theory. The nuclear matter distribution deduced for
11Li exhibits a very pronounced halo structure, the matter radius of
11Li being significantly larger than those of the
6,8,9Li isotopes. The data on
8,9Li are consistent with the existence of sizable neutron skins in these nuclei. The obtained data allow for a test of various theoretical model calculations of the structure of the studied neutron-rich nuclei.
We calculate the differential cross sections for proton elastic scattering on the exotic halo nuclei
6
He and
8
He at energies around ~0.7 GeV at the momentum transfers squared up to 0.30 (GeV/
c
)
2
...and investigate the influence of the nucleon centre-of-mass correlations on the calculated cross sections. In particular, we show that the approximate account of the centre-of-mass correlations used previously considerably overestimates the cross sections at high values of the momentum transfer.
We calculate the differential cross sections for proton elastic scattering on the exotic halo nuclei sup.6He and sup.8He at energies around ~0.7 GeV at the momentum transfers squared up to 0.30 ...(GeV/c).sup.2 and investigate the influence of the nucleon centre-of-mass correlations on the calculated cross sections. In particular, we show that the approximate account of the centre-of-mass correlations used previously considerably overestimates the cross sections at high values of the momentum transfer.
This paper presents a review of studies on the spatial structure of light exotic nuclei performed by the PNPI-GSI collaboration. A series of experiments has been carried out in beams of exotic nuclei ...with an energy of 0.7 GeV/nucleon at the Helmholtz Center for Heavy Ion Research (GSI, Darmstadt), in which the differential cross sections for proton–nucleus small-angle scattering in inverse kinematics have been measured using the ionization spectrometer IKAR developed at PNPI. An analysis of the measured cross sections has allowed us to determine the nuclear matter distributions in the studied nuclei of the He, Li, Be, B, and C isotopes and also to determine the halo sizes in
6
He,
11
Li,
14
Be,
8
B, and
15
C nuclei.
In order to clear up the sensitivity of the nucleus-nucleus reaction cross sections
σ
R
to the nuclear matter distributions in exotic halo nuclei, we have calculated the values of
σ
R
for scattering ...of
6
He,
11
Li, and
19
C nuclei on several nuclear targets at the energy of 0.8 GeV/nucleon. The calculations were performed in the “rigid target” approximation to the Glauber theory, different shapes of the nuclear density distributions in
6
He,
11
Li, and
19
C being assumed.
In order to clear up the sensitivity of the nucleus-nucleus scattering to the nuclear matter distributions in exotic halo nuclei, we have calculated differential cross sections for elastic scattering ...of the
6
He and
11
Li nuclei on several nuclear targets at the energy of 0.8 GeV/nucleon with different assumed nuclear density distributions in
6
He and
11
Li.
New experimental method for investigation of the nucleon polarizabilities Yevetska, O.; Watzlawik, S.; Ahrens, J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2010, Letnik:
618, Številka:
1
Journal Article
Recenzirano
At the continuous wave (cw) Superconducting Darmstadt Electron Linear Accelerator S-DALINAC, a new method has been developed for the determination of the electric (
α
¯
) and magnetic (
β
¯
) ...polarizabilities of the proton and the deuteron. For that purpose the energy and angular dependence of the differential cross-section for elastic
γ
p
and
γ
d
scattering of bremsstrahlung photons in the energy range between 20 and 100
MeV is measured by detecting the recoiling proton (deuteron) in coincidence with the scattered bremsstrahlung photon.
α
¯
and
β
¯
are then found by means of a best fit to a theoretical description of the scattering cross-section with these quantities as open parameters. The experimental setup consists of a bremsstrahlung photon facility, two specially designed high pressure hydrogen (deuterium) ionization chambers which serve as targets and detectors of the recoil proton (deuteron), NaI gamma spectrometers and several additional detectors for beam diagnostics and normalization. The whole setup was tested using bremsstrahlung photon beams with endpoint energies of 60 and 79.3
MeV. The results of the test experiments show that future high-statistics measurements are feasible.
In order to study the spatial structure of exotic nuclei, it was proposed at the Petersburg Nuclear Physics Institute (PNPI) to measure the differential cross section for small-angle proton elastic ...scattering in inverse kinematics. Several experiments in beams of 0.7-GeV/nucleon exotic nuclei were performed at the heavy-ion accelerator facility of GSI (Gesellschaft für Schwerionenforschung, Darmstadt, Germany) by using the IKAR ionization spectrometer developed at PNPI. The IKAR ionization chamber filled with hydrogen at a pressure of 10 bar served simultaneously as a target and as a recoil-proton detector, which measured the recoil-proton energy. The beam-particle scattering angle was also measured. The results obtained for the cross sections in question were analyzed on the basis of the Glauber-Sitenko theory using phenomenological nuclear-density distributions with two free parameters. Nuclear-matter distributions and root-mean-square radii were found for the nuclei under investigation. The size of the halo in the
6
He,
8
He,
11
Li, and
14
Be nuclei was determined among other things. Information about neutron distributions in nuclei was deduced by combining the data obtained here with the known values of the radii of proton distributions. A sizable neutron skin was revealed in the
8
Li,
9
Li, and
12
Be nuclei.
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