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1.
The paper presents the results on differential cross sections for elastic scattering of 7+-, K+-mesons and protons on protons in the 4-momentum transfer squared range 0·08 ¦t¦ 1·0 (GeV/c)2 and incident particle momentum of 29 and 43 GeV/c for pions and kaons and 29, 43, 50 and 65 GeV/c for protons. The measurements were taken with the spectrometer Sigma, installed in the positive beam of the IHEP accelerator.Presented by F. A. Yotch at the Symposium on Hadron-Hadron Scattering at High Energies, Liblice, Czechoslovakia, June 16–21, 1975.The authors would like to express their gratitude to A. A.Logunov, Yu. D.Prokoshkin, L. D.Soloviev and V. A.Yarba for their support of this experiment. We are indebted to CERN Administration for giving us a permission to use a part of equipment of the CIBS spectrometer and to W.Kienzle for useful discussions.  相似文献   

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<正>(Updated September 2013.COMPAS group.IHEP,Protvino)Using new results from FNAL-COLLIDER-D0 experiment in pp elastic collisions at s~(1/2)=1.96 TeV[1],CERN-LHC-TOTEM experiment in p p elastic collisions at s~(1/2)=7,8 TeV[2-3]and PAO experiment in proton-air collisions at 57 TeV[4]the amplitudes of the elastic p p and p p collisions are investigated in a most broad region in s~(1/2)and t via three observables da/dt(s,t).σ~(tot)(s),and p(s).The summary of the database for dσ/dt(s,t)is presented in Figure 50.10.where projection of the dσ/dt(s~(1/2),t)to the(da/dt,—t)plane orthogonal to the s~(1/2)axis is displayed.  相似文献   

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The excitation functions of 40Ar(p,p′γ)40Ar and 40Ar(p,γ)41K reactions are measured in the E p = 1.0–3.0 eV range of accelerated protons. The excitation function in the E p > 2.6 MeV range of accelerated protons is measured for the first time. The strengths of all (more than 200) measured resonance states are calculated.  相似文献   

6.
The double diffractive J/ψ, hard production processes is discussed. Assuming that Pomeron has parton distributions and dominated by gluons with behavior as 1/x when x is small, the energy dependance of the cross section, for above processes is calculated and compared with both the cross section of single diffractive hard scattering and of Drell-Yan processes . It is shown that the is similar with and increases as (lnS)2 at superhigh energies. It is emphasized that this character may provide a new method for detecting physical particles at energy ranges of SSC.  相似文献   

7.
Based on three methods of particle identification (PID) of BES,we study the identification of p and p in momentum range from 0.3 to 1.2 GeV using real particle samples of e,μ,π,K,p and p which were collected in 2-5GeV R scan,J/(ψ) and ψ′ data taking periods. The paper presents the optimized method of PID:p(p) is identified by dE/dx only if momentum below 0.6GeV,and by TOF or the combination of dE/dx and TOF for higher momentum.The PID efficiency of p, p and contamination from the other charged particles are also given.  相似文献   

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We describe the production of (AA) in p(p) collisions using a constituent quark model which has been successfully applied to the N(N)system.  相似文献   

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The excitation functions for the reactions of radiative proton capture, 64Zn(p,γ)65Ga and 66Zn(p,γ)67Ga, which are of interest for stellar nucleosynthesis, have been measured in the range of incidentproton energies from 1 to 2.8 MeV. The astrophysical S factor and reaction rates have been derived from the reaction cross sections. The experimental results are compared with the predictions of the Hauser-Feshbach statistical theory.  相似文献   

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《Nuclear Physics A》1997,626(3):751-759
18F radioactive beams were used to measure the 18F(p,α) reaction in the c.m. energy ranges of 265–535 keV and 550–740 keV. In each case, a resonant level was clearly detected, of which the resonant strength and some other properties were deduced. The astrophysical reaction rate was calculated down to the novae peak temperature. Consequences for the hot CNO cycles were drawn.  相似文献   

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Properties of secondaries associated with a high-p T charged trigger particle (3<p T <5 GeV/c) were studied for αp and αα interactions at c.m. energies \(\sqrt s = 88\) GeV and 125 GeV, respectively. Thep T distributions of secondaries in the away-jet and trigger-jet regions were compared with those for high-p T pp interactions. No statistically significant differences were seen, except at lowp T . Momentum and angular distributions of spectator and leading protons were studied as a function of charge and rapidity of the trigger hadron. The observed correlations between trigger charge and number of spectator protons provide evidence of valence quark contributions to the trigger jet.  相似文献   

13.
In this paper we briefly review the transverse momentum dependent generalized parton model and its application to the study of azimuthal asymmetries in the distribution of leading hadrons (mainly pions) inside large transverse momentum jets inclusively produced in polarized proton-proton collisions. We put particular emphasis on the phenomenological interest of these observables, in combination with similar asymmetries measured in semi-inclusive deeply inelastic scattering, Drell-Yan processes and e + e ? collisions, for the study of the universality properties of the transverse momentum dependent parton distribution and fragmentation functions. We present results for RHIC kinematics at center-of-mass energies √s = 200 and 500 GeV, for central and mainly forward jet rapidities, in particular for the Sivers distribution and the Collins fragmentation function, that are believed to be responsible for many of the largest asymmetries measured in the last years. We also briefly discuss the case of inclusive jet production and recent phenomenological applications of other theoretical approaches, like the colour gauge invariant generalized parton model and the collinear twist-three approach, aiming at clarifying the issues of the universality and process dependence of transverse momentum dependent functions.  相似文献   

14.
The cross-sections for the reactions of the strange production p + p ↦ p + Λ + K+ and p + p ↦ p + Σ0 + K+ near thresholds of the final states pΛK+ and pΣ0K+ are calculated in the effective Lagrangian approach. Our approach is based on the dominant contribution of the one-pion exchange and strong interaction of the colliding protons in the initial state. The theoretical values of the cross-sections agree reasonably well with the experimental data. The polarization properties of the Λ- and Σ0-hyperons are discussed.  相似文献   

15.
We analyze the available experimental data on the backward production processes N and N in the framework of the strong-cut Reggeized absorption model, which is based on the exchange of the baryon Regge trajectoriesN and with the associated cuts. The model describes rather well the data on the differential cross sections at incident momenta ranging from 2.15 to 20 GeV/c. An essential contribution of exchange even at small energies (E lab of the order of a few GeV) is found. A model-independent analysis of data confirms this fenomena.  相似文献   

16.
The evaluation of two-centre Coulomb-penetration and exchange-penetration integrals is discussed. All possible penetration integrals between 2 and 3 atomic orbitals exponent α are reduced analytically and tabulated for α = 1·00 (0·25) 10·00.  相似文献   

17.
Using the shell model wave functions, we have studied quadrupole moments of medium-weight and heavy hypernuclei, and obtained the shell model values of quadrupole moments of NΛ systems ( N = p and n). With the use of the first-order perturbation theory, we have also estimated the configuration mixing effects on quadrupole moments of these NΛ hypernuclei. We show that the hyperon-induced configuration mixing effects are small and the nucleon-induced configuration mixing effects are large in many cases. Received: 22 February 2000 / Accepted: 2 August 2000  相似文献   

18.
The quantum group GL p,q(2) is known to be related to the Jordanian GLh,h(2) via a contraction procedure. It can also be realised using the generators of the Hopf algebra G r,s. We contract the G r,s quantum group to obtain its Jordanian analogue G m,k, which provides a realisation of GLh,h(2) in a manner similar to the q-deformed case.  相似文献   

19.
A new highly modular and generic Partial Wave Analysis (PWA) software package including a general framework for future hadron spectroscopy experiments like PANDA is currently under development. The aims and present status of the software package are summarized and the first PWA results obtained with the already existing tools are presented. These analyses are mainly focused on important aspects of antiproton proton annihilation processes with relevance for the PANDA experiment. For this purpose Crystal Barrel LEAR data are currently under investigation in order to gain a deeper insight to the production mechanisms of vector mesons. In addition analyses for the identification of resonances in radiative J / ψ decays from BESIII data are summarized.  相似文献   

20.
Abstract

Fractionation of the rigid polymer, poly(p‐phenylene benzobisthiazole) (PBZT), was carried out in dilute solution in concentrated methane sulfuric acid (MSA) using silica gels as packing material of a column. Several combinations of the average chain length of the fractionating materials and the average pore diameter of the gels were examined to improve fractionation resolution. The gels with average pore diameter near the average chain length resulted in high fractionation resolution. Single crystals of the fractionated and unfractionated PBZTs were observed by transmission electron microscopy (TEM). Both single crystals were fundamentally composed of rod crystals with the chain orienting normal to the rods. The unfractionated PBZT made a cluster of parallel rod crystals, where longer chains penetrated a few rod crystals leaving their chain ends within the crystalline core. On the contrary, with the fractionated polymer, extended‐chain rod‐like crystals were dispersed, isolated from each other. This morphology enables us to estimate the chain length visibly by TEM, for which a few milligrams of the material is enough for the observation.  相似文献   

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