共查询到20条相似文献,搜索用时 93 毫秒
1.
K. Olimov V. V. Glagolev S. L. Lutpullaev A. Kurbanov A. K. Olimov V. I. Petrov A. A. Yuldashev 《Physics of Atomic Nuclei》2011,74(2):268-271
Results of a comparative analysis of processes leading to the production of mirror nuclei 7Li and 7Be in 16Op collisions at a momentum of 3.25 GeV/c per nucleon are presented. A comparison of associated multiplicities of accompanying particles is performed. The first results
on the mean multiplicity of neutrons appearing as fragments are described. 相似文献
2.
New experimental data on fluctuations in the multiplicities of negatively charged particles in interactions of light nuclei
(p, d, 4He, 12C) with carbon nuclei at a momentum of 4.2 A GeV/c in 4π geometry are reported. The data indicate a behavior similar to that earlier observed by the NA49 Collaboration. The
cascade evaporation model, FRITIOF model, and UrQMD 1.3 model are used to analyze the data. The dependence of the fluctuations
on nuclear collision centrality is theoretically described without any exotic assumptions. According to the FRITIOF model,
the dependence of the multiplicity fluctuations on the collision centrality is to a large extent governed by fluctuations
in the number of “wounded” nucleons that are associated with the experimental observation conditions. The NA49 Collaboration
data are also described. 相似文献
3.
We give results for the energy of the 4He and 16O nuclei using the auxiliary field diffusion Monte Carlo and a path constraint. We compare the results with previous FHNC and cluster Monte Carlo calculations.Received: 1 November 2002, Published online: 15 July 2003PACS:
21.10.Dr Binding energies and masses - 21.60.Ka Monte Carlo models 相似文献
4.
K. Olimov V. V. Glagolev K. G. Gulamov S. L. Lutpullaev A. K. Olimov V. I. Petrov A. A. Yuldashev 《Physics of Atomic Nuclei》2012,75(1):48-52
New experimental data on the dependences of the mean multiplicities and kinematical characteristics of deuterons produced
in 16Op collisions at a momentum of 3.25 GeV/c per nucleon on the degree of excitation of the fragmenting nucleus are presented. These experimental data are compared with
the predictions of the cascade-fragmentation-evaporation model. 相似文献
5.
Kh. K. Olimov 《Physics of Atomic Nuclei》2009,72(1):77-84
The formation of cumulative nuclei of 4He in 16Op collisions at a momentum of 3.25 GeV/c per nucleon was investigated for the first time under conditions of 4π acceptance. The slope parameter of the invariant cross sections for the formation of cumulative nuclei of 4He was determined, and new data on the correlations between the yield of these cumulative nuclei and the yield of charged particles and fragments in 16Op interactions were obtained. 相似文献
6.
V. V. Glagolev S. L. Lutpullaev A. K. Olimov K. Olimov A. A. Usarov E. Kh. Bazarov V. I. Petrov B. S. Yuldashev 《Physics of Atomic Nuclei》2007,70(3):421-426
A comparative analysis of the inclusive production of 3H and 3He nuclei in 16Op interactions at a momentum of 3.25 GeV/c per nucleon is performed, and it is shown that the formation of these mirror nuclei occurs under close physical conditions, the distinction between their binding energies having no significant effect on the formation of the nuclei. 相似文献
7.
Kh. K. Olimov 《Physics of Atomic Nuclei》2009,72(4):601-606
The production of cumulative three-nucleon nuclei (3H and 3He) in 16Op collisions at a momentum of 3.25 GeV/c per nucleon were studied for the first time under conditions of 4π geometry. The slope parameter of the cross section for the production of cumulative three-nucleon nuclei was determined, and new data on correlations of the yields of A = 3 cumulative nuclei, charged particles, and fragments in 16Op interactions are reported. The properties of cumulative and noncumulative events were found to be substantially different, and evidence for the presence of a common universal feature in the mechanisms for the cumulative production of hadrons and light nuclear fragments was obtained. 相似文献
8.
We obtain exact results in α′ for open and closed A-model topological string amplitudes on a large class of toric Calabi-Yau threefolds by using their correspondence with five
dimensional gauge theories. The toric Calabi-Yaus that we analyze are obtained as minimal resolution of cones over Y
p,q
manifolds and give rise via M-theory compactification to SU(p) gauge theories on . As an application we present a detailed study of the local case and compute open and closed genus zero Gromov-Witten invariants of the orbifold. We also display the modular structure of the topological wave function and give predictions for higher genus amplitudes.
The mirror curve in this case is the spectral curve of the relativistic A
1 Toda chain. Our results also indicate the existence of a wider class of relativistic integrable systems associated to generic
Y
p,q
geometries. 相似文献
9.
E. Kh. Bazarov V. V. Glagolev K. G. Gulamov M. Yu. Kratenko S. L. Lutpullaev K. Olimov Kh. Sh. Khamidov A. A. Yuldashev B. S. Yuldashev 《Physics of Atomic Nuclei》2005,68(8):1395-1399
Experimental data on inclusive deuteron production in 16Op collisions at high energies were obtained for the first time under conditions of 4π geometry. An irregularity in the momentum spectrum of deuterons in the rest frame of oxygen nuclei is found in the range 0.40 ≤ p ≤ 0.55 GeV/c, and the reasons for its appearance are discussed. The mean multiplicities of secondary fragments are correlated with the presence of deuterons in an event, these correlations being positive for fragments of charge in the range z f ≤ 4 and negative for fragments of charge in the range 5 ≤ z f ≤ 7. This is likely to be due to baryon-charge conservation. 相似文献
10.
A. N. Vodin I. V. Ushakov G. E. Tuller 《Bulletin of the Russian Academy of Sciences: Physics》2008,72(7):1005-1008
It is inferred from the analysis of the experimental data that the reduced probabilities of isovector l-forbidden M1 transitions achieve maximum values in nuclei with a magic core. The minimum values are related to γ transitions in nuclei
belonging to the region of stable deformation with A ≈ 25. Isovector l-forbidden M1 transitions in mirror nuclei are explored. The ratio of the reduced probabilities for proton and neutron transitions shows
the maximum deviation from the theoretical evaluations for the pair of nuclei 41Ca-41Sc consisting of the even-even magic core 40Ca and one nucleon outside the closed 1d2s shell. 相似文献
11.
V. E. Tarasov V. V. Khabarov A. E. Kudryavtsev V. M. Weinberg 《Physics of Atomic Nuclei》2008,71(8):1410-1423
The Kd reactions are considered in the impulse approximationwithNN final-state interactions (FSI) taken into account. Realistic parameters for the KN phase shifts are used. The “quasi-elastic” energy region, in which the elementary KN interaction is predominantly elastic, is considered. The theoretical predictions are compared with the data on the K
+
d → K
+
pn, K
+
d → K0
pp, K
+
d → K
+
d, and K
+
d total cross sections. The NN FSI effect in the reaction K
+
d → K
+
pn has been found to be large. The predictions for the Kd cross sections are also given for slow kaons, produced from ϕ(1020) decays, as the functions of the isoscalar KN scattering length a
0. These predictions can be used to extract the value of a
0 from the data.
The text was submitted by the authors in English. 相似文献
12.
The experimental study of the proton-rich nuclei close to the N = Z line is a constant challenge for nuclear spectroscopy, mainly due to the difficulty to produce them with the currently available beam/target combinations. Significant advances on this direction were obtained from experiments performed with the GASP array during the last two years: the yrast line of 84Mo was extended up to 10 + , 88Ru observed for the first time, and the N = Z + 1 line was mapped from 81Zr to 95Ag. These new results allow us to have a more complete image of the transition from the well-deformed shell closure at N,Z = 40 to the spherical-shell closure at N,Z = 50, and highlights some particular effects that can be observed only in the vicinity of the N = Z line.Received: 10 January 2003, Published online: 23 March 2004PACS:
21.10.-k Properties of nuclei; nuclear energy levels - 21.10.Pc Single-particle levels and strength functions - 21.10.Re Collective levels - 23.20.-g Electromagnetic transitions 相似文献
13.
During the last decade, as the experimental and computing means and techniques have rapidly evolved, the experimental investigation of the f7/2-shell nuclei has gained renewed interest. TheN = Z nuclei studied with the GASP array range from 44Ti to 52Fe. The results extended the knowledge of their structure up to high spins and excitation energies, above band terminations, where the competition with the charged-particles emission was initially thought to obscure the possibility of gamma-ray spectroscopy investigation. The paper highlights some of the most outstanding properties of these nuclei such as the nuclear rotation and backbending effects, band termination states, yrast traps, non-natural parity bands, competition between T = 0 and T = 1 pn pairing modes.Received: 30 October 2002, Published online: 16 March 2004PACS:
21.10.-k Properties of nuclei; nuclear energy levels - 21.60.Cs Shell model - 23.20.Lv
transitions and level energies - 27.40. + z
C.A. Ur: On leave from NIPNE Bucharest, Romania 相似文献
14.
Jingke Li 《Mathematical Physics, Analysis and Geometry》2010,13(4):287-297
In this paper,we introduce a new norm on C
(1)(X), which is induced by a hexagon on R
2, and prove that every isometric operator on C
(1)(X) can be induced by a homeomorphism of X, where X is a connected subset of R. 相似文献
15.
S. B. Dubovichenko 《Physics of Atomic Nuclei》2011,74(3):358-370
Within the potential cluster model where orbital states are classified according to Young diagrams and isospin, astrophysical
S factors are considered for radiative proton capture by 3H and 7Li nuclei at energies of up to 1 and 10 keV, respectively. It is shown that the approach used, which takes into account only
the E1 transition for the p
3H capture process, makes it possible to describe well the most recent experimental data at c.m. energies in the range from
50 keV to 5MeV. In the case of proton capture by 7Li nuclei, an M1 processwas taken into account in addition to the E1 transition, and a general behavior and the magnitude of the experimental S factor could be correctly reproduced owing to this at astrophysical energies, including the region around the resonance at
0.441 MeV (in the laboratory frame). 相似文献
16.
The effect of polarization of the 6Li and 3H clusters on the parameters of states of the 7Li nucleus and on the cross section for the reaction 6Li(n,3H)4He was studied. The 4He + d + n three-cluster configuration was invoked for this purpose, and cluster dynamics was determined within a microscopic model
where the relative motion of the clusters was described in terms of Faddeev amplitudes. The 4He + d + n three-cluster configuration made it possible to consider the 4He + 3H and 6Li + n binary channels, which are dominant in 7Li, and to take simultaneously into account the cluster polarization of 6Li as a two-cluster subsystemin the 4He + d representation and the cluster polarization of 3Has a two-cluster subsystem in the d + n representation. 相似文献
17.
S. B. Dubovichenko 《Russian Physics Journal》2011,54(2):157-164
The experimental data on the astrophysical S-factor of the p
2H radiative capture are well described for energies from 1 keV to 10 MeV using the potential cluster model and the Young schemes
of orbital cluster state classification with allowance for the E1 and M1 transitions. 相似文献
18.
Complementing the preceding study of charged scalar leptons, the sector of the neutral scalar leptons, sneutrinos, is investigated in a high-precision analysis for future e
+
e
- linear colliders. The theoretical predictions for the cross-sections are calculated at the thresholds for non-zero widths and in the continuum including higher-order corrections at the one-loop level. Methods for measuring the sneutrino masses and the electron-sneutrino-gaugino Yukawa couplings are presented, addressing theoretical problems specific for the sneutrino channels.Received: 10 September 2004, Revised: 11 October 2004, Published online: 3 March 2005 相似文献
19.
Tom Melia Paolo Nason Raoul Rontsch Giulia Zanderighi 《The European Physical Journal C - Particles and Fields》2011,71(6):1670
We present an implementation of the calculation of the production of W
+
W
+ plus two jets at hadron colliders, at next-to-leading order (NLO) in QCD, in the POWHEG framework, which is a method that allows the interfacing of NLO calculations to shower Monte Carlo programs. This is the
first 2→4 process to be described to NLO accuracy within a shower Monte Carlo framework. The implementation was built within
the POWHEG BOX package. We discuss a few technical improvements that were needed in the POWHEG BOX to deal with the computer intensive nature of the NLO calculation, and argue that further improvements are possible, so that
the method can match the complexity that is reached today in NLO calculations. We have interfaced our POWHEG implementation with PYTHIA and HERWIG, and present some phenomenological results, discussing similarities and differences between the pure NLO and the POWHEG+PYTHIA calculation both for inclusive and more exclusive distributions. We have made the relevant code available at the POWHEG BOX web site. 相似文献
20.
From a macroscopic theory of the quantum vacuum in terms of conserved relativistic charges (generically denoted by q
(a) with label a), we have obtained, in the low-energy limit, a particular type of f(R) model relevant to cosmology. The macroscopic quantum-vacuum theory allows us to distinguish between different phenomenological
f(R) models on physical grounds.
The text was submitted by the authors in English. 相似文献