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.
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.
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.
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.
Results of several experiments aimed at exploring the nuclear spatial structure of neutron-rich He and Li isotopes are presented and briefly discussed. The study of the density distributions in these ...nuclei by small-angle proton elastic scattering at intermediate energy is considered in more detail. The performed investigations allow one to obtain information on the total matter distributions, radii of the matter, neutron and proton distributions, effective and internal core sizes, halo sizes, and spatial correlations of the halo nucleons in the studied nuclei.