Proposals of possible experiments based on employing a spin-physics detector (SPD) at the first stage of implementation of the NICA (Nuclotron based Ion Collider fAcility) research program are ...considered. The proposals include studies of collisions of polarized and unpolarized proton and deuteron beams at effective nucleon–nucleon energies of
GeV in the center-of-mass frame.
It is shown that the ratio of the deuteron and proton analyzing powers in proton-deuteron elastic scattering at small angles is sensitive to subtle effects in a theoretical description. These include ...the transverse spin-spin term in the elementary nucleon-nucleon amplitudes and double-scattering corrections. On the other hand there is far less sensitivity to the spin-orbit amplitude and to binding or other kinematic effects associated with the use of the deuteron, as either target or projectile. The available data are in agreement with the results of a refined Glauber theory model.
In the interaction of a transversely polarized nuclear beam with a tensor-polarized deuteron target, a nonzero value of the component of the total cross section corresponding to this combination of ...polarizations is an unambiguous signal of
-invariance violation while
-parity is preserved. The method developed earlier for calculating this component of the total cross section for
scattering based on the Glauber theory has been generalized by us to the case of
3
He
scattering, and its energy dependence in the range of beam energies 0.1–1 GeV/nucleon has been calculated. It is found that in
3
He
collisions, in contrast to
scattering, the contribution of only one type of
-violating nucleon-nucleon forces dominates, which is essential for extraction of the unknown constant of this interaction from the corresponding data.
Differential cross sections for elastic
He scattering at energies in the range of
MeV and proton analyzing powers of this process are calculated on the basis of the Glauber diffraction model with ...allowance for the spin dependence of nucleon–nucleon amplitudes. Explicit expressions are obtained for the first time for all six invariant amplitudes of
He scattering for the mechanisms of single, double, and triple incident-proton scattering off target nucleons. Good agreement with experimental data is found both for the cross sections and for spin observables in the forward hemisphere of scattering angles. Also, explicit expressions are obtained for
He-scattering amplitudes violating time-reversal (
) invariance but preserving spatial parity (
). These expressions can be used in testing
invariance in this and other processes.
.
The dimensional scaling of the differential cross sections of binary reactions,
, where
n
is given by constituent quark counting rules, was predicted for asymptotically high energies
and ...transferred momenta
at
t
/
s
= const (here
s
and
t
are the Mandelstam variables and m
i
denotes a hadron mass), but manifested itself at surprisingly moderate energies of few GeV at large fixed cms angles
. This behaviour is observed not only in reactions with free hadrons, but with the deuteron and
3
He too, both for electromagnetic and pure hadronic interactions. One may suppose that the observed scaling points out to effective restoration of near-conformal and, probably, chiral symmetry in these processes. A systematical experimental study of the scaling behaviour of the reactions with the deuteron,
3
H,
3
He, and
4
He nuclei is still absent. We consider a possibility to carry out this study in
dd
collisions at the JINR Nuclotron.
Time-reversal breaking and parity-conserving millistrong interactions, suggested in 1965, still remain a viable mechanism of CP-violation beyond the Standard Model. One of its possible manifestations ...is the T-odd asymmetry in the transmission of tensor-polarized deuterons through a vector-polarized hydrogen gas target. Upon the rotation of the deuteron polarization from the vertical direction into the ring plane, the T-odd asymmetries, odd against the reversal of the proton polarization in the target, will continuously oscillate with first or second harmonics of the spin precession frequency. The Fourier analysis of the oscillating T-odd asymmetries allows for an easy separation from background persistent in conventional experiments employing static vector and tensor polarizations.
The exclusive reaction
12
C(
p
,
pNN
)
10
A of the quasi-elastic knockout of a nucleon from short-range correlated nucleon pair
in the
12
С nucleus by a proton with an energy of several ...gigaelectronvolts is considered in the plane-wave approximation. The translational invariant shell model with intermediate coupling is used to calculate two-nucleon spectroscopic factors for the
pairs. Relativistic effects in the
p
+
→
p
+
N
+
N
process are considered within light front dynamics.
The total cross section for the interaction of transversely polarized protons
p
p
y
and deuterons that have a tensor polarization
P
x
z
provides a null-test signal of
T
-invariance violation under ...the condition of
P
invariance. The relevant experiment is planned by the PAX Collaboration at the COSY accelerator with protons accelerated to the energy of 135 MeV. A modified Glauber theory is used here to calculate the differential spin observables
A
y
,
C
y,y
,
C
xz,y
,
C
z,x
, and
C
x,z
and the differential and total cross sections for proton-deuteron scattering in the case of
T
-even
P
-even proton-nucleon interactions. This makes it possible to estimate background conditions of the planned experiment.
The formalism developed earlier for elastic pd scattering on the basis of Glauber theory with allowance for a total spin dependence is modified by replacing pN amplitudes by amplitudes for Nsup.12C ...scattering and is applied to elastic deuteron scattering on the sup.12C nucleus. The amplitudes for elastic Nsup.12C scattering are obtained within the optical model. Respective numerical calculations performed at the kinetic deuteron-beam energy of 270 MeV lead to results that agree well with data on the differential cross section for dsup.12C scattering into the forward hemisphere, but the calculated spin observable A.sup.d.sub.y agrees with experimental data only qualitatively.
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