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1.
Quasiclassical trajectory method for the title reaction He +H2+ → HeH+ + H was carried out on the potential energy surface which was revised by Aquilanti et al. [Chem. Phys. Lett. 469, 26 (2009)]. The initial vibrational quantum number of reactant was set as v=1, v=2 and v=3. Stereodynamics information of the reaction was obtained, such as the distributions of product angular momentum P(θ r ), P(ϕ r ),p(ϕ r , θ r ) and the two commonly used polarization-dependent differential cross sections (PDDCSs) (2π/σ)( 00/ t ) and (2π/σ)( 20/ t ), to get the alignment and orientation of product molecules. The results show that the influence of both the collision energy and vibrational quantum number (v) to the reaction are highly sensitive.  相似文献   

2.
胡梅  刘新国  谭瑞山 《物理学报》2014,63(2):23402-023402
基于我们最近所构建的Ar+H+2→ArH++H(12A′)反应的新势能面,采用准经典轨线法研究了碰撞能分别为0.48,0.77,1.24 eV以及能量为0.48 eV时反应物不同振动态下Ar+H+2→ArH++H反应的立体动力学性质.结果显示在给定的碰撞能情况下,以及当反应物振动量子数由0变到2时计算的积分反应截面与实验值符合得较好.通过比较发现,碰撞能对此反应k-j′关联函数P(θr)分布的影响大于其受振动激发的影响,并且关于k-k′-j′三矢量相关的函数P(?r)分布以及极化微分反应截面对碰撞能较敏感,同时发现振动激发对P(?r)分布和极化微分反应截面也有较大的影响.  相似文献   

3.
肖静  杨传路  王美山 《中国物理 B》2012,21(4):43101-043101
The vector correlations between products and reagents for the reactions Ne+H + 2 , Ne+D + 2 , and Ne+T + 2 are calculated by means of the quasi-classical trajectory method on a new potential energy surface constructed by Lü et al. [J. Chem. Phys. 2010 132, 014303]. The polarization-dependent differential cross-sections (2π/σ)(dσ 00 /dω t ), (2π/σ)(dσ 20 /dω t ), (2π/σ)(dσ 22+ /dω t ), and (2π/σ)(dσ 21 /dω t ), and the distributions of P (θ r ), P (φ r ), and P (θ r ,φ r ) are calculated. The isotopic effect, which is associated with the difference in mass factor among the three reactions, is revealed.  相似文献   

4.
The decay B0 d→D+D- offers an interesting probe of CP violation, but it requires control of penguin effects, which can be done through B0 s→D+ sD- s by means of the U-spin flavour symmetry of strong interactions. Recently, the Belle collaboration reported indications of large CP violation in the B0 d decay, which were, however, not confirmed by BaBar, and first signals of the B0 s channel were observed at the Tevatron. In view of these developments and the quickly approaching start of the LHC, we explore the allowed region in observable space for CP violation in B0 d→D+D-, perform theoretical estimates of the relevant hadronic penguin parameters and observables, and we address questions both about the most promising strategies for the extraction of CP-violating phases and about the interplay with other measurements of CP violation and the search for new physics. As far as the latter aspect is concerned, we point out that the B0 q→Dq +D- q system provides a setting for the determination of the B0 q–B̄0 q mixing phases (q∈{d,s}) that is complementary to the conventional B0 d→J/ψKS and B0 s→J/ψφ modes with respect to possible new-physics effects in the electroweak penguin sector.  相似文献   

5.
The branching ratios and photon spectra of the rare processes ρ(ω) → π 0 π 0 γ, ρ(ω) → ηπ 0 γ are calculated in the framework of the standard local quark Nambu-Jona-Lasinio model. Three types of diagrams are considered: the quark box and the pole diagrams with scalar (σ, α 0(980)) and vector (ρ, ω) mesons. The obtained estimates for the widths of the processes ρ(ω) → π 0 π 0 γ are in satisfactory agreement with existing experimental data. Predictions are made for the widths of the processes ρ(ω) → ηπ 0 γ. The text was submitted by the authors in English.  相似文献   

6.
The difference of the energies of levels Δ n = E lev(2+0 n ) − E lev(0+0 n ) at n = 1, 2, and 3 and the multipole-mixture parameter δ for (2+02−2+01) and (2+03−2+01) transitions are contrasted against the structure of the K π = 02+ and 03+ rotational bands that was calculated on the basis of the quasiparticle-phonon model. The values of (Δ2 − Δ1), (Δ3 − Δ1), and (Δ2 − Δ3) are found to correlate with the sign of the parameter δ and with the calculated structure of the K π = 02+ and 03+ bands. Original Russian Text ? A.M. Demidov, L.I. Govor, V.A. Kurkin, I.V. Mikhailov, 2009, published in Yadernaya Fizika, 2009, Vol. 72, No. 2, pp. 236–240.  相似文献   

7.
We present the results of a search for and study of the resonance effects in the system of π+π from the reaction npnpπ+π at the momentum of quasi-monochromatic neutrons P n = (5.20 ± 0.12) GeV/c from the data obtained in an exposure of the 1-m hydrogen bubble chamber of Veksler and Baldin Laboratory of High Energies, Joint Institute for Nuclear Research (VBLHE JINR). After the supplementary selection of the events where a secondary proton was emitted in the forward hemisphere in the general c.m.s. of the reaction (cosθ* p > 0) in the effective mass spectrum of π+π combinations, we found nine peculiarities at the masses (350 ± 3), (408 ± 3), (489 ± 3), (579 ± 5), (676 ± 7), (762 ± 11), (878 ± 7), (1036 ±13), and (1170 ± 11) MeV/c 2 with experimental widths of no more than several tens of MeV/c 2. We carried out a direct measurement of the spins of resonances and also obtained other quantum numbers. All of these peculiarities have a similar set of quantum numbers I G (J PC ) = 0+ (0++). We investigated a sequence of scalar-isoscalar resonances f 00) with masses in the range M ≤ 1200 MeV/c 2. We found a phenomenological dependence of the resonance mass on its number. This dependence covered not only the resonances shown in this paper, but also those present in PDG tables with quantum numbers of f 00) mesons.  相似文献   

8.
Radiative decays π 0(π 0′) → γ + γ, π 0′ρ 0(ω) + γ, ρ 0′(ω′) → π 0 + γ, ρ 0′(ω′) → π 0′ + γ, and some processes of π 0′ production at lepton colliders are considered in the framework of the nonlocal SU(2) × SU(2) Nambu-Jona-Lasinio model. Mixing of the radially excited and the ground meson states is taken into account. Numerical results for the decay and production processes are presented.  相似文献   

9.
10.
Using a sample of over 400 million φ→KSKL decays produced during the years 2001 and 2002 at the DAΦNE e+e- collider, the ratio RS π=Γ(KS→π+π-(γ))/Γ(KS→π0π0) has been measured with the KLOE detector. The result is RS π=2.2555±0.0012stat±0.0021corr-stat±0.0050syst, which is in good agreement with the previously published result based on the KLOE data sample from the year 2000. The average of the KLOE results is RS π=2.2549±0.0054, reducing the total error by a factor of three, to 0.25%.  相似文献   

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