HYPERON POLARIZATION IN QUARK-DIQUARK CASCADE MODEL

2007 ◽  
Vol 16 (07n08) ◽  
pp. 2344-2349
Author(s):  
TSUTOMU TASHIRO ◽  
HUJIO NODA ◽  
SHIN-ICHI NAKARIKI ◽  
KAZUMI FUKUMA

We relate the hyperon polarizations in proton-proton and proton-nucleus collisions to the leading particle effect and use the constituent quark-diquark cascade model with SU(6) wave function. We assume that the quantization axis is characterized by the production normal of the leading baryon of the most massive cascade chain and the incident valence diquark tends to pick up a spin down sea quark or conversely a sea diquark preferentially combines with the spin up incident valence quark to form a leading baryon as compared with the spin down valence quark.

1998 ◽  
Vol 2 (4) ◽  
pp. 733-740 ◽  
Author(s):  
Tsutomu Tashiro ◽  
Hujio Noda ◽  
Shin-ichi Nakariki ◽  
Kazuo Ishii ◽  
Kisei Kinoshita

2004 ◽  
Vol 19 (04) ◽  
pp. 599-611 ◽  
Author(s):  
TSUTOMU TASHIRO ◽  
SHIN-ICHI NAKARIKI ◽  
HUJIO NODA ◽  
KISEI KINOSHITA ◽  
SHUXIN LAN

We discuss the hadroproductions of Λc, [Formula: see text], D and [Formula: see text] in the framework of the constituent quark–diquark cascade model taking into account the valence quark annihilation. The spectra of Λcand [Formula: see text] in pA, Σ-A and π-A collisions are well explained by the model using the values of parameters used in hadroproductions of D and [Formula: see text]. It is shown that the role of valence diquark in the incident baryon is important for [Formula: see text] productions as well as for Λcproduction.


2012 ◽  
Vol 21 (01) ◽  
pp. 1250001
Author(s):  
HUJIO NODA ◽  
TSUTOMU TASHIRO ◽  
SHIN-ICHI NAKARIKI

We discuss the relation between the polarization of inclusively produced (anti)hyperons and the incident baryon states in the framework of the constituent quark–diquark cascade model. We assume that there is an intrinsic diquark–antidiquark state in the incident baryon, in which the intrinsic diquark immediately fragments into a non-leading baryon and the antidiquark behaves as a valence constituent. It is also assumed that the valence (anti)diquark in the incident nucleon tends to combine selectively with a spin-down sea quark and, on the other hand, the spin-up valence quark in the projectile is chosen by a sea (anti)diquark in preference to the spin-down valence quark. It is found that the incident spin-1/2 baryon is mainly composed of a spin-0 valence diquark and a valence quark, and contains an intrinsic diquark–antidiquark state with a probability of about 7%.


2009 ◽  
Vol 24 (27) ◽  
pp. 2167-2174 ◽  
Author(s):  
H. FRITZSCH ◽  
G. ELDAHOUMI

The constituent quarks are interpreted as bound states, which have an internal structure. The quark distributions of the proton are related to those of the constituent quarks. The experiments support this hypothesis. Likewise the spin structure of the proton is related to the spin structure of the constituent quarks. We find that about 30% of the spin of a constituent quark is given by the valence quark, and 70% are provided by the gluons.


2014 ◽  
Vol 29 (15) ◽  
pp. 1450096 ◽  
Author(s):  
V. V. Anisovich ◽  
K. V. Nikonov ◽  
V. A. Nikonov ◽  
J. Nyiri

The LHC energies are those at which the asymptotic regime in hadron–hadron diffractive collisions (pp, πp, ππ) might be switched on. Based on results of the Dakhno–Nikonov eikonal model which is a generalization of the Good–Walker eikonal approach for a continuous set of channels, we present a picture for transformation of the constituent quark mode to the black disk one. In the black disk mode [Formula: see text], we have a growth of the logarithm squared type for total and elastic cross-sections, σ tot ~ ln 2 s and σ el ~ ln 2 s and [Formula: see text]-scaling for diffractive scattering and diffractive dissociation of hadrons. The diffractive dissociation cross-section grows as σD ~ ln s, σDD ~ ln s, and their relative contribution tends to zero: σD/σ tot → 0, σDD/σ tot → 0. Asymptotic characteristics of diffractive and total cross-sections are universal, and this results in the asymptotical equality of cross-sections for all types of hadrons (the Gribov universality). The energy scale for switching on the asymptotic mode is estimated for different processes.


1981 ◽  
Vol 62 (3) ◽  
pp. 238-252 ◽  
Author(s):  
M. Giffon ◽  
E. Predazzi

1996 ◽  
Vol 11 (38) ◽  
pp. 3021-3034 ◽  
Author(s):  
H. WEIGEL ◽  
L. GAMBERG ◽  
H. REINHARDT

We study nucleon structure functions within the bosonized Nambu-Jona-Lasinio model where the nucleon emerges as a chiral soliton. As examples we present the unpolarized structure functions for the νp and [Formula: see text] scattering and discuss the Gottfried sum rule in the valence quark approximation. This approximation is justified for moderate constituent quark masses (~ 400 MeV) as the valence quark level dominates the predictions of nucleon properties. We find that these structure functions are well localized in the interval 0≤x Bj ≤1 permitting a parton model interpretation.


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