The differential cross sections of the charge exchange reaction
d
p
→
(
p
p
)
n
has been measured at 1.75 GeV/c per nucleon for small transferred momenta using the one arm magnetic spectrometer ...STRELA at the Nuclotron accelerator in JINR Dubna. The ratio of the differential cross section of the charge exchange reaction
d
p
→
(
p
p
)
n
to that of the
n
p
→
p
n
elementary process is discussed in order to estimate the spin-dependent part of the
n
p
→
p
n
charge exchange amplitude. The
n
p
→
p
n
amplitude turned out to be predominantly spin-dependent.
The relative angle correlations of intermediate mass fragments has been studied for
12
C + Au collisions at 22 GeV. Strong suppression at small angles is observed which is due to the Coulomb ...repulsion of fragments. The experimental correlation function was compared to that obtained by the multibody Coulomb trajectory calculations with the various decay time of fragmenting system. It is found that the average decay time of fragmenting system is less than 59 ± 11 fm
c
–1
.
The analyzing powers for proton elastic scattering (
p
A
→
p
X
) and neutron charge exchange (
n
A
→
p
X
) reactions on nuclei have been measured on
C
,
CH
,
C
H
2
and
Cu
targets at incident neutron ...momenta 3.0–4.2 GeV/c by detecting one charged particle in forward direction. The polarized neutron measurements are the first of their kind. The experiment was performed using the Nuclotron accelerator in JINR Dubna, where polarized neutrons and protons were obtained from break-up of a polarized deuteron beam which has a maximum momentum of 13 GeV/c. The polarimeter ALPOM2 was used to obtain the analyzing power dependence on the transverse momentum of the final-state nucleon. These data have been used to estimate the figure of merit of a proposed experiment at Jefferson Laboratory to measure the recoiling neutron polarization in the quasi-elastic
2
H
(
e
,
e
′
n
)
reaction, which yields information on the charge and magnetic elastic form factors of the neutron.
Invariant cross sections of carbon fragments are investigated for
p
(3.6 GeV)
+
Au collisions in terms of longitudinal versus transversal velocity components. It is found that fragments are emitted ...by one slowly moving source.
Abstract
The analyzing powers for neutron charge exchange
nA
→
pX
reactions on nuclei have been measured on C, CH2 and Cu targets at incident neutron momenta 3.0 - 4.2 GeV/c by detecting one charged ...particle in forward direction. The polarized neutron measurements are the first of their kind. The experiment was performed using the Nuclotron accelerator in JINR Dubna, where polarized neutrons and protons were obtained from breakup of a polarized deuteron beam which has a maximum momentum of 13 GeV/c. The polarimeter ALPOM2 was used to obtain the analyzing power dependence on the transverse momentum of the final-state nucleon. These data have been used to estimate the figure of merit of a proposed experiment at Jefferson Laboratory to measure the recoiling neutron polarization in the quasi-elastic
2
H
(
e
,
e
′
n
) reaction, which yields information on the charge and magnetic elastic form factors of the neutron.
The analyzing powers for neutron charge exchange nA → pX reactions on nuclei have been measured on C, CH2 and Cu targets at incident neutron momenta 3.0 - 4.2 GeV/c by detecting one charged particle ...in forward direction. The polarized neutron measurements are the first of their kind. The experiment was performed using the Nuclotron accelerator in JINR Dubna, where polarized neutrons and protons were obtained from breakup of a polarized deuteron beam which has a maximum momentum of 13 GeV/c. The polarimeter ALPOM2 was used to obtain the analyzing power dependence on the transverse momentum of the final-state nucleon. These data have been used to estimate the figure of merit of a proposed experiment at Jefferson Laboratory to measure the recoiling neutron polarization in the quasi-elastic 2H(e, e′n) reaction, which yields information on the charge and magnetic elastic form factors of the neutron.
Exposures of test samples of nuclear track emulsion were analyzed. The formation of high-multiplicity nuclear stars was observed upon irradiating nuclear track emulsions with ultrarelativistic muons. ...Kinematical features studied in this exposure of nuclear track emulsions for events of the muon-induced splitting of carbon nuclei to three α-particles are indicative of the nuclear-diffraction interaction mechanism.
The differential cross sections of the charge exchange reaction dp → (pp)n has been measured at 1.75 GeV c momentum per nucleon for small transferred momenta using the one arm magnetic spectrometer ...STRELA at the Nuclotron accelerator. The ratio of the differential cross section of the charge exchange reaction dp → (pp)n to that of the np → pn elementary process is discussed in order to estimate the spin-dependent part of the np → pn charge exchange amplitude on the basis of dp → (pp)n data. The np → pn amplitude turned out to be predominantly spin-dependent.
The reaction p + CH2→ forward charge particle + X is used for this aim traditionally. Analyzing power of this reaction falls off as 1 p, where p is the laboratory momentum. At the proton momenta of ...order 8 GeV c, which are expected at the JLab experiment, the low analyzing power creates problems for off-line analysis of data. On the other hand, it is well known that the reaction p+p → p+p has the much more analyzing power. So, the calorimeter is predestinated for suppression of inelastic events in this reaction. In the report it is shown that the problem is solved quite well.
The results obtained by estimating the contribution of 8Be and 9B nuclei to the coherent dissociation of
10
C,
10
B, and
12
C relativistic nuclei in nuclear track emulsions (“white” stars) are ...presented. The selection of white stars accompanied by 9B leads to a distinct peak appearing in the distribution of the excitation energy of 2α2
p
ensembles and having a maximum at 4.1 ± 0.3 MeV. A 8Be nucleus manifests itself in the coherent-dissociation reaction
10
B →
2
He + H with a probability of (25 ± 5)%, (14 ± 3)% of it being due to 9B decays. The ratio of the branching fractions of the
9
B +
n
and
9
Be +
p
mirror channels is estimated at 6 ± 1. An analysis of the relativistic dissociation of
12
C nuclei in a nuclear track emulsion revealed nine 3α events corresponding to the Hoyle state.
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