Effect of unitarization on the amplitudes for the decays K10 → π+π? and K+ → π+π+π?

The unitarization of the amplitude for the decay process K ₁⁰ → π⁺π⁻ and allowance for the rescattering of final-state pions in the decay process K ⁺ → π⁺π⁺π⁻ make it possible to evaluate, by using the parameters extracted from data on K → 2π decays, the K ⁺ → π⁺π⁺π⁻ decay width. The result agrees with the experimental width value at a level of a few percent. Allowance for corrections for higher order terms of the momentum expansion of the amplitude for the decay process K ⁺ → π⁺π⁺π⁻ leads to the slope-parameter value of g ₊₊₋^th = 0.2182, which agrees with its experimental counterpart, g ₊₊₋^exp = 0.2154 ± 0.0035.     

e+e－→π+π－π+π－形状因子拟合

基于BABAR实验组对e⁺e^－→π⁺π^－π⁺π^－的反应截面的测量结果, 用VMD模型给出的理论截面拟合实验数据, 首次从单一反应道得到π⁺π^－π⁺π^－末态形状因子的所有参数值.     

On the spin correlations of muons generated in the annihilation process e + e ? → μ+μ?

Using the technique of helicity amplitudes, the electromagnetic process e ⁺ e ⁻ → μ⁺μ⁻ is theoretically investigated in the one-photon approximation. The structure of the triplet states of the final (μ⁺μ⁻) system is analyzed. It is shown that in the case of unpolarized electron and positron the finalmuons are also unpolarized, but their spins are strongly correlated. Explicit expressions for the components of the correlation tensor of the final (μ⁺μ⁻) system are derived. The formula for the angular correlation at the decays of final muons μ⁺ and μ⁻, produced in the process e ⁺ e ⁻ → μ⁺μ⁻, is obtained. It is demonstrated that spin correlations of muons in the process of electron-positron pair annihilation have the purely quantum character, since one of the incoherence inequalities for the correlation-tensor components is always violated. The additional contribution of the weak interaction of lepton neutral currents through the virtual Z ⁰ boson is considered; it is established that, taking into account the weak interaction, the qualitative character of the muon spin correlations does not change. The text was submitted by the authors in English.     

Perturbations in the A1Π-X1Σ+ system of the BeO molecule

All perturbations observed by Lagerqvist (Thesis, University of Stockholm, 1948) in the A¹Π-X¹Σ⁺ transition have been assigned to a³Π₂, a³Π₁, and X¹Σ⁺ states. Vibrational and rotational constants of the a³Π state as well as electronic parameters for A ～ X, A ～ a, and a ～ X interactions have been determined.

     

5.

Vibrational analysis of Fourier transform spectrum of the A³Π₀-X¹Σ⁺ and B³Π₁-X¹Σ⁺ transitions of indium monobromide     

Renu Singh  K. N. Uttam  M. D. Saksena  M. N. Deo 《Pramana》2009,73(5):889-899

The emission spectrum of InBr molecule has been recorded in the region 350–400 nm on BOMEM DA8 Fourier transform spectrometer at an apodized resolution of 0.06 cm⁻¹ using microwave excitation technique. About 61 violet degraded and single headed bands have been recorded and are classified into two band systems, viz. A³Π₀-X¹Σ⁺ and B³Π₁-X¹Σ⁺. A few new bands have been observed and are fitted in the vibrational schemes of the two systems. Revised vibrational constants have been determined. The vibrational assignments have been confirmed by observing isotope effect due to InBr⁸¹ in the 30 bands of the A³Π₀-X¹Σ⁺ system and 19 bands of the B³Π₁-X¹Σ⁺ system. The analysis is further supported by calculating the Franck-Condon factor for InBr⁷⁹ and InBr⁸¹ molecules. The following vibrational constants (in cm⁻¹) have been determined from the analysis:      

6.

Reaction e ⁺ e ^? → π ⁺ π ^? π ⁺ π ^? at energies of √ s ≤ 1 GeV     

N. N. Achasov  A. A. Kozhevnikov 《JETP Letters》2008,88(1):1-4

The e ⁺ e ⁻ → π ⁺ π ⁻ π ⁺ π ⁻ cross section is calculated for energies of 0.65 ≤ √s ≤ 1 GeV in the framework of the generalized hidden local symmetry model. The calculations are compared with the data of CMD-2 and BaBaR. It is shown that the inclusion of heavy isovector resonances ρ(1450) and ρ(1700) is necessary for reconciling calculations with the data. It is found that, at √s ≈ 1 GeV, the contributions of the above resonances are much larger, by a factor of 30, than the ρ(770) one, and amount to a considerable fraction ∼0.3–0.6 of the latter at √s ∼ m _ρ. The text was submitted by the authors in English.     

7.

ρ⁰ production the reaction ξξ→3π⁺3π^?ξξ→ρ⁰ρ⁰(1700)     

H. -J. Behrend  L. Criegee  J. H. Field  G. Franke  H. Jung  J. Meyer  O. Podobrin  V. Schr?der  G. G. Winter  P. J. Bussey  et al. 《Zeitschrift fur Physik C Particles and Fields》1991,49(1):43-48

We have studied the ⁰ production rate in the reaction 3⁺3^– in the energy range 1.6W 7.5 GeV with the CELLO detector at PETRA. Our analysis points to a substantial yield of ^00+– events in particular atW >4.0 GeV. We give cross sections for the ⁰2⁺2^– and ^00+– final states and calculate upper limits for the reaction ⁰⁰ (1700) ^00+–.Now at CERN     

8.

Vibration-rotation and deperturbation analysis of A²Π-X²Σ⁺ and B²Σ⁺-X²Σ⁺ systems of the CaI molecule     

David E Reisner  Peter F Bernath  R.W Field 《Journal of Molecular Spectroscopy》1981,89(1):107-124

Doppler-limited laser excitation spectroscopy employing narrow-band fluorescence detection was used to obtain a rotational and vibrational analysis in the (0, 0) and (1, 1) bands of the A²Π-X²Σ⁺ system and the (4, 2) (3, 1), (0, 0), (0, 1), (1, 2), (2, 3), and (3, 4) bands of the B²Σ⁺-X²Σ⁺ system of CaI. The A and B states are deperturbed to obtain spectroscopic constants and Franck-Condon factors. Deperturbation was necessary because of the small separation of the A and B states relative to the A ～ B interaction strength and the A²Π spin-orbit splitting. The main deperturbed constants (in cm^?1) are

	Reciprocal centimeters
	Te	ωe	ωexe	Be	αe	re (Å)
a3Π	8574	1132	8.4	1.3675	?0.0168	1.4623

     

9.

QED corrections in the radiative return method during measurement of the e⁺e^?→π⁺π^? cross-section below 1 GeV     

M. I. Konchatnij  N. P. Merenkov  O. N. Shekhovtzova 《JETP Letters》2003,78(2):51-56

     

10.

Theoretical study of the A ³ 0 ⁺ ← X ¹ 0 ⁺ and B ³ 1 ← X ¹ 0 ⁺ transitions in the Cd-rare gas van der Waals molecules     

E. Czuchaj  M. Kro&#;nicki  J. Czub 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,13(3):345-353

Excitation spectra arising from A ³ 0 ⁺ ← X ¹ 0 ⁺ and B ³ 1 ← X ¹ 0 ⁺ electronic transitions in the Cd-rare gas (RG) van der Waals molecules are calculated using newly obtained theoretical potential curves for these species. In the molecular structure calculations, Cd²⁰⁺ and RG⁸⁺ cores are simulated by energy-consistent pseudopotentials which also account for scalar-relativistic effects and spin-orbit (SO) interaction within the valence shell. Potential energies in the Λ S coupling scheme have been obtained by means of ab initio complete-active-space multiconfiguration self consistent-field (CASSCF)/complete-active-space multireference second-order perturbation theory (CASPT2) calculations with a total 28 correlated electrons, while the SO matrix has been computed in a reduced CI space restricted to the CASSCF level. The final Ω potential curves are obtained by diagonalization of the modified SO matrix (its diagonal elements before diagonalization substituted for the corresponding CASPT2 eigen-energies). The spectroscopic parameters for the ground and several excited states of the Cd-RG complexes deduced from the calculated potential curves are in quite reasonable agreement with available experimental data. In addition, the radial Schr?dinger equation for nuclear motion was solved numerically with the calculated potentials to evaluate the corresponding vibrational levels and radial wavefunctions. The latter have been used in the calculation of the appropriate Franck-Condon factors to yield information on relative intensities of the vibrational bands of the Cd-RG complexes. The theoretical vibrational progressions are discussed in the context of experimental spectra. Received 10 August 2000 and Received in final form 7 November 2000     

11.

F₂ Σ⁺ -X ²Σ ⁺Band System of Cobalt Carbide     

郭静茹  张朝霞  王婷婷  陈从香  陈旸 《化学物理学报》2008,21(6):505-509

用脉冲直流放电产生Xe原子亚稳态5p56s[3/2]2和5p56s′[1/2]0.在单光子28000－42000cm-1能量范围内,结合飞行时间质谱技术获得Xe原子共振增强激发光谱.光谱分析表明,所有谱线来源于Xe原子5p56s[3/2]2和5p56s′[1/2]0两个亚稳态吸收单个光子向偶宇称np′、nf′自电离Rydberg态序列的跃迁.实验观测到许多新的自电离能级,并获得更精确和系统的能级位置和量子亏损值数据.     

12.

钾双原子分子2¹∑⁺_u─x¹∑⁺sub>g跃迁连续谱带研究     

吕志伟  刘莉  何伟明  王骐  马祖光  李路 《光学学报》1996,16(8):1092-1095

理论计算了钾双原子分子21∑+ｕ─ｘ1∑+ｇ跃迁所得到的扩散带荧光谱，并与Gondal等[4]和Luh等[5]以及Milosevic等[6]的实验结果进行了比较。计算结果与Luh等和Milosevic等的实验结果符合很好，排除了600 nm附近扩散带来自Ｋ221∑+ｕ─ｘ1∑+ｇ跃迁的可能性。     

13.

Laser spectroscopy of CaBr: A²Π-X²Σ⁺ and B²Σ⁺-X²Σ⁺ systems     

P.F. Bernath  R.W. Field  B. Pinchemel  Y. Lefebvre  J. Schamps 《Journal of Molecular Spectroscopy》1981,88(1):175-193

Laser excitation spectra have been recorded for Ca⁷⁹Br and Ca⁸¹Br in the spectral region 600–630 nm. The use of a 1-m monochromator as a narrow band pass filter (1–2 cm^?1) has allowed rotational analysis of the 0-0, 1-1, and 2-2 bands of the B²Σ⁺ - X²Σ⁺ transition and the 0-0 and 1-1 bands of the A²Π - X²Σ⁺ transition. A few additional lines of the 0-1, 1-2, 1-0, and 2-1 bands of the B-X system were used to obtain band origins for vibrational analysis. The main constants for Ca⁷⁹Br are (in cm^?1):

	$\text{X}{}^2\text{Σ}{}^{\mathrm{+}}$	$\text{A}{}^2\text{Π}$	$\text{B}{}^2\text{Σ}{}^{\mathrm{+}}$
$\text{T}{}_{\mathrm{e}}$	0	15 624.67(5)	15 700.52(12)
$\text{ω}{}_{\mathrm{e}}$	238.7496(33)	241.19(7)	242.63(17)
$\text{ω}{}_{\mathrm{e}}\text{χ}{}_{\mathrm{e}}$	0.62789(64)	0.53(5) (Pekeris)	1.17(12) (Pekeris)
$\text{B}{}_{\mathrm{e}}$	0.0693254(84)	0.070460(14)	0.071572(22)
$\text{α}{}_{\mathrm{e}}\text{× 10}{}^4$	2.640(35)	2.15(10)	3.95(2)
$\text{A}{}_{\mathrm{e}}$	—	45.8968(52)	—
$\text{R}{}_{\mathrm{e}}\text{(}\text{A}\text{?}\text{)}$	2.8286(2)	2.8057(3)	2.7839(4)

     

14.

射流冷却AlO自由基B²Σ⁺—X²Σ⁺光谱研究          下载免费PDF全文

金瑾  陈旸  裴林森  胡长进  马兴孝  陈从香 《物理学报》2000,49(9):1689-1691

利用铝电极放电产生的Al原子与O₂反应生成AlO自由基,在超声射流冷却下在43 0—480nm波长范围观测到AlO自由基B—X跃迁的激光诱导荧光激发谱.光谱振动结构分析表明 所有的谱带属于V′-V″=1,2,3跃迁,并获得基态和激发态的振动频率与非谐性常数.另外还 对其中(1,4)谱带的转动结构进行标识,并得到相应的转动常数和离心畸变系数.对从基态 振动能级V″=5向上跃迁的谱带强度增强进行了讨论. 关键词： 光谱 AlO     

15.

BF分子A¹Π→X¹Σ⁺带系与b³Σ⁺→a³Π带系的Franck-Condon因子计算          下载免费PDF全文

张中明  熊烨 《物理学报》1997,46(11):2124-2129

在双原子分子核运动的波动方程中，计入分子的振转相互作用项，得出的波函数除与振动量子数有关外，还与转动量子数有关．用该波函数编程序计算了BF分子A¹Π→X¹Σ⁺带系和b³Σ⁺→a³Π带系的Franck-Condon因子．计算中转动量子数的取值由J=0取至J=200，结果适用于低温、高温和强激波条件． 关键词：     

16.

Beam Energy Dependence of the π^-/π⁺ Ratio          下载免费PDF全文

张芳左维  雍高产 《中国物理快报》2006,23(12):3230-3233

Using the isospin- and momentum-dependent hadronic transport model IBUU04, the effects of symmetry energy on the π^-/π^＋ ratio are studied. Our investigations are based on the calculations of the ^132 Sn＋^124Sn semi-central collisions at beam energies of 400/AMeV, 600/A MeV and 800/A MeV. It is found that both the transverse momentum and kinetic energy distributions of the π^-/π^＋ ratio are rather sensitive to the symmetry energy, especially around the Coulomb peaks. The position of the Coulomb peak is shown to be nearly independent of beam energy. The sensitivity of the π^-/π^＋ ratio to the symmetry energy decreases as the beam energy increases from 600/A MeV to 800/A MeV.     

17.

B ^?→ K ₁^*? (1270)(→ ρ ⁰ K ^?) ? ⁺ ? ^? in LEET     

S. Rai Choudhury  A. S. Cornell  Naveen Gaur 《The European Physical Journal C - Particles and Fields》2008,58(2):251-259

Flavor changing neutral current (FCNC) decays of the B-meson are a very useful tool for studying possible physics scenarios beyond the standard model (SM), where of the many FCNC modes radiative, purely leptonic and semi-leptonic decays of the B-meson are relatively clean tests. Within this context, the BELLE collaboration has measured the process B→K ^* γ and also searched for the B→K ₁(1270)γ process. Theoretical analyses of these processes are yielding similar values of the relevant form factors. In this work we have used this upper bound in studying the angular correlations for the related semi-leptonic decay mode B ⁻→K ₁⁻(1270)(→ρ ⁰ K ⁻)ℓ ⁺ ℓ ⁻, where we have used the form factors that have already been estimated for the B→K ₁(1270)γ mode. Note that the additional form factors that are required were calculated using large energy effective theory (LEET).     

18.

P-branch emission spectra of the A¹Π-X¹Σ⁺ system of IrN          下载免费PDF全文

樊群超  孙卫国  李会东  冯灏 《中国物理 B》2012,21(2):23301-023301

The P-branch emission spectra of (4,1) and (3,1) bands of the A¹Π-X¹Σ⁺ system of IrN molecule are studied using an analytical formula which is derived from elementary expression of molecular total energy by taking multiple spectral differences. It not only reproduces the known experimental transition lines, but also predicts the unknown spectral lines up to J= 80 for each band by using a group of fifteen known experimental transition lines.     

19.

A study of the reactions π⁺p→ K⁺∑⁺ and K⁻p→π⁻∑⁺ at 10 GeV/c     

A. Berglund  T. Buran  P.J. Carlson  C.J.S. Damerell  I. Endo  A.R. Gillman  V. Gracco  R.J. Homer  M.J. Hotchkiss  A. Lundby  M. Macri  B.N. Ratcliff  A. Santroni  T. Tso  F. Wickens  J.A. Wilson 《Physics letters. [Part B]》1975,57(1):100-104

For the first time, the reactions π⁺p→K⁺∑⁺ and K^?p→π^?∑⁺ have been studied in the same apparatus. This has been done at an adequately high momentum (10.1 GeV/c) to allow a check of the prediction of exchange degeneracy, that the differential cross sections should be converging at high energy. We have measured the cross section for momentum transfers t between t_min and t = ?0.3 (GeV/c)². We find that for both reactions the differential cross section shows an exponential fall, with no deviations right in to t =t_min (where some other experiments have shown a dip in the cross section). Furthermore, we find the magnitude of the differential cross sections to be closely similar at t = 0, with a ratio

$\text{R=}\text{(}\text{d}\text{σ}\text{d}\text{t)}{}_{\mathrm{t=0}}\text{(}\text{K}{}^{\mathrm{?}}\text{p}\text{→π}{}^{\mathrm{?}}\text{∑}{}^{\mathrm{+}}\text{)}\text{(}\text{d}\text{σ}\text{d}\text{t)}{}_{\mathrm{t=0}}\text{(π}{}^{\mathrm{+}}\text{p}\text{→}\text{K}{}^{\mathrm{+}}\text{∑}{}^{\mathrm{+}}$

However, the slope for the positive reaction is about 19% steeper than that for the negative reaction.     

20.

a₂(1320)→π⁺π⁺π^－过程的三体振幅分析     

朱界杰  阮图南 《中国物理 C》1998,22(4):326-332

对a₂(1320)→π⁺π⁺π^－过程的衰变振幅进行张量分析,展示了如何得到三体衰变振幅.     

	$\text{X}{}^2\text{Σ}{}^{\mathrm{+}}$	$\text{A}{}^2\text{Π}$	$\text{B}{}^2\text{Σ}{}^{\mathrm{+}}$
$\text{T}{}_{\mathrm{e}}$	0	15 958.41 (10)	16 383.137 (6)
$\text{ω}{}_{\mathrm{e}}$	285.732 (9)	288.56 (20)	285.747 (9)
$\text{ω}{}_{\mathrm{e}}\text{χ}{}_{\mathrm{e}}$	0.840 (4)	—	0.954 (4)
$\text{B}{}_{\mathrm{e}}$	0.094466141 (30)	0.0957343 (20)	0.0965151 (20)
$\text{α}{}_{\mathrm{e}}$	0.000403551 (40)	0.0004327 (20)	0.0004483 (15)
$\text{γ}{}_{\mathrm{e}}$ (spin-rot.)	0.00301484 (50)	—	0.068767 (79)
$\text{P}{}_{\mathrm{e}}$	—	?0.066834 (64)	—
$\text{A}{}_{\mathrm{e}}$	—	59.175 (1)	—

Vibrational analysis of Fourier transform spectrum of the A3Π0-X1Σ+ and B3Π1-X1Σ+ transitions of indium monobromide

The emission spectrum of InBr molecule has been recorded in the region 350–400 nm on BOMEM DA8 Fourier transform spectrometer at an apodized resolution of 0.06 cm⁻¹ using microwave excitation technique. About 61 violet degraded and single headed bands have been recorded and are classified into two band systems, viz. A³Π₀-X¹Σ⁺ and B³Π₁-X¹Σ⁺. A few new bands have been observed and are fitted in the vibrational schemes of the two systems. Revised vibrational constants have been determined. The vibrational assignments have been confirmed by observing isotope effect due to InBr⁸¹ in the 30 bands of the A³Π₀-X¹Σ⁺ system and 19 bands of the B³Π₁-X¹Σ⁺ system. The analysis is further supported by calculating the Franck-Condon factor for InBr⁷⁹ and InBr⁸¹ molecules. The following vibrational constants (in cm⁻¹) have been determined from the analysis:      

Reaction e + e ? → π + π ? π + π ? at energies of √ s ≤ 1 GeV

The e ⁺ e ⁻ → π ⁺ π ⁻ π ⁺ π ⁻ cross section is calculated for energies of 0.65 ≤ √s ≤ 1 GeV in the framework of the generalized hidden local symmetry model. The calculations are compared with the data of CMD-2 and BaBaR. It is shown that the inclusion of heavy isovector resonances ρ(1450) and ρ(1700) is necessary for reconciling calculations with the data. It is found that, at √s ≈ 1 GeV, the contributions of the above resonances are much larger, by a factor of 30, than the ρ(770) one, and amount to a considerable fraction ∼0.3–0.6 of the latter at √s ∼ m _ρ. The text was submitted by the authors in English.     

ρ0 production the reaction ξξ→3π+3π?ξξ→ρ0ρ0(1700)

We have studied the ⁰ production rate in the reaction 3⁺3^– in the energy range 1.6W 7.5 GeV with the CELLO detector at PETRA. Our analysis points to a substantial yield of ^00+– events in particular atW >4.0 GeV. We give cross sections for the ⁰2⁺2^– and ^00+– final states and calculate upper limits for the reaction ⁰⁰ (1700) ^00+–.Now at CERN     

Vibration-rotation and deperturbation analysis of A2Π-X2Σ+ and B2Σ+-X2Σ+ systems of the CaI molecule

Doppler-limited laser excitation spectroscopy employing narrow-band fluorescence detection was used to obtain a rotational and vibrational analysis in the (0, 0) and (1, 1) bands of the A²Π-X²Σ⁺ system and the (4, 2) (3, 1), (0, 0), (0, 1), (1, 2), (2, 3), and (3, 4) bands of the B²Σ⁺-X²Σ⁺ system of CaI. The A and B states are deperturbed to obtain spectroscopic constants and Franck-Condon factors. Deperturbation was necessary because of the small separation of the A and B states relative to the A ～ B interaction strength and the A²Π spin-orbit splitting. The main deperturbed constants (in cm^?1) are

Theoretical study of the A 3 0 + ← X 1 0 + and B 3 1 ← X 1 0 + transitions in the Cd-rare gas van der Waals molecules

Excitation spectra arising from A ³ 0 ⁺ ← X ¹ 0 ⁺ and B ³ 1 ← X ¹ 0 ⁺ electronic transitions in the Cd-rare gas (RG) van der Waals molecules are calculated using newly obtained theoretical potential curves for these species. In the molecular structure calculations, Cd²⁰⁺ and RG⁸⁺ cores are simulated by energy-consistent pseudopotentials which also account for scalar-relativistic effects and spin-orbit (SO) interaction within the valence shell. Potential energies in the Λ S coupling scheme have been obtained by means of ab initio complete-active-space multiconfiguration self consistent-field (CASSCF)/complete-active-space multireference second-order perturbation theory (CASPT2) calculations with a total 28 correlated electrons, while the SO matrix has been computed in a reduced CI space restricted to the CASSCF level. The final Ω potential curves are obtained by diagonalization of the modified SO matrix (its diagonal elements before diagonalization substituted for the corresponding CASPT2 eigen-energies). The spectroscopic parameters for the ground and several excited states of the Cd-RG complexes deduced from the calculated potential curves are in quite reasonable agreement with available experimental data. In addition, the radial Schr?dinger equation for nuclear motion was solved numerically with the calculated potentials to evaluate the corresponding vibrational levels and radial wavefunctions. The latter have been used in the calculation of the appropriate Franck-Condon factors to yield information on relative intensities of the vibrational bands of the Cd-RG complexes. The theoretical vibrational progressions are discussed in the context of experimental spectra. Received 10 August 2000 and Received in final form 7 November 2000     

F2 Σ+ -X 2Σ +Band System of Cobalt Carbide

用脉冲直流放电产生Xe原子亚稳态5p56s[3/2]2和5p56s′[1/2]0.在单光子28000－42000cm-1能量范围内,结合飞行时间质谱技术获得Xe原子共振增强激发光谱.光谱分析表明,所有谱线来源于Xe原子5p56s[3/2]2和5p56s′[1/2]0两个亚稳态吸收单个光子向偶宇称np′、nf′自电离Rydberg态序列的跃迁.实验观测到许多新的自电离能级,并获得更精确和系统的能级位置和量子亏损值数据.     

钾双原子分子21∑+u─x1∑+sub>g跃迁连续谱带研究

理论计算了钾双原子分子21∑+ｕ─ｘ1∑+ｇ跃迁所得到的扩散带荧光谱，并与Gondal等[4]和Luh等[5]以及Milosevic等[6]的实验结果进行了比较。计算结果与Luh等和Milosevic等的实验结果符合很好，排除了600 nm附近扩散带来自Ｋ221∑+ｕ─ｘ1∑+ｇ跃迁的可能性。     

Laser spectroscopy of CaBr: A2Π-X2Σ+ and B2Σ+-X2Σ+ systems

Laser excitation spectra have been recorded for Ca⁷⁹Br and Ca⁸¹Br in the spectral region 600–630 nm. The use of a 1-m monochromator as a narrow band pass filter (1–2 cm^?1) has allowed rotational analysis of the 0-0, 1-1, and 2-2 bands of the B²Σ⁺ - X²Σ⁺ transition and the 0-0 and 1-1 bands of the A²Π - X²Σ⁺ transition. A few additional lines of the 0-1, 1-2, 1-0, and 2-1 bands of the B-X system were used to obtain band origins for vibrational analysis. The main constants for Ca⁷⁹Br are (in cm^?1):

射流冷却AlO自由基B2Σ+—X2Σ+光谱研究

利用铝电极放电产生的Al原子与O₂反应生成AlO自由基,在超声射流冷却下在43 0—480nm波长范围观测到AlO自由基B—X跃迁的激光诱导荧光激发谱.光谱振动结构分析表明 所有的谱带属于V′-V″=1,2,3跃迁,并获得基态和激发态的振动频率与非谐性常数.另外还 对其中(1,4)谱带的转动结构进行标识,并得到相应的转动常数和离心畸变系数.对从基态 振动能级V″=5向上跃迁的谱带强度增强进行了讨论. 关键词： 光谱 AlO     

BF分子A1Π→X1Σ+带系与b3Σ+→a3Π带系的Franck-Condon因子计算

在双原子分子核运动的波动方程中，计入分子的振转相互作用项，得出的波函数除与振动量子数有关外，还与转动量子数有关．用该波函数编程序计算了BF分子A¹Π→X¹Σ⁺带系和b³Σ⁺→a³Π带系的Franck-Condon因子．计算中转动量子数的取值由J=0取至J=200，结果适用于低温、高温和强激波条件． 关键词：     

Beam Energy Dependence of the π-/π+ Ratio

Using the isospin- and momentum-dependent hadronic transport model IBUU04, the effects of symmetry energy on the π^-/π^＋ ratio are studied. Our investigations are based on the calculations of the ^132 Sn＋^124Sn semi-central collisions at beam energies of 400/AMeV, 600/A MeV and 800/A MeV. It is found that both the transverse momentum and kinetic energy distributions of the π^-/π^＋ ratio are rather sensitive to the symmetry energy, especially around the Coulomb peaks. The position of the Coulomb peak is shown to be nearly independent of beam energy. The sensitivity of the π^-/π^＋ ratio to the symmetry energy decreases as the beam energy increases from 600/A MeV to 800/A MeV.     

B ?→ K 1*? (1270)(→ ρ 0 K ?) ? + ? ? in LEET

Flavor changing neutral current (FCNC) decays of the B-meson are a very useful tool for studying possible physics scenarios beyond the standard model (SM), where of the many FCNC modes radiative, purely leptonic and semi-leptonic decays of the B-meson are relatively clean tests. Within this context, the BELLE collaboration has measured the process B→K ^* γ and also searched for the B→K ₁(1270)γ process. Theoretical analyses of these processes are yielding similar values of the relevant form factors. In this work we have used this upper bound in studying the angular correlations for the related semi-leptonic decay mode B ⁻→K ₁⁻(1270)(→ρ ⁰ K ⁻)ℓ ⁺ ℓ ⁻, where we have used the form factors that have already been estimated for the B→K ₁(1270)γ mode. Note that the additional form factors that are required were calculated using large energy effective theory (LEET).     

P-branch emission spectra of the A1Π-X1Σ+ system of IrN

The P-branch emission spectra of (4,1) and (3,1) bands of the A¹Π-X¹Σ⁺ system of IrN molecule are studied using an analytical formula which is derived from elementary expression of molecular total energy by taking multiple spectral differences. It not only reproduces the known experimental transition lines, but also predicts the unknown spectral lines up to J= 80 for each band by using a group of fifteen known experimental transition lines.     

A study of the reactions π+p→ K+∑+ and K−p→π−∑+ at 10 GeV/c

For the first time, the reactions π⁺p→K⁺∑⁺ and K^?p→π^?∑⁺ have been studied in the same apparatus. This has been done at an adequately high momentum (10.1 GeV/c) to allow a check of the prediction of exchange degeneracy, that the differential cross sections should be converging at high energy. We have measured the cross section for momentum transfers t between t_min and t = ?0.3 (GeV/c)². We find that for both reactions the differential cross section shows an exponential fall, with no deviations right in to t =t_min (where some other experiments have shown a dip in the cross section). Furthermore, we find the magnitude of the differential cross sections to be closely similar at t = 0, with a ratio

$\text{R=}\text{(}\text{d}\text{σ}\text{d}\text{t)}{}_{\mathrm{t=0}}\text{(}\text{K}{}^{\mathrm{?}}\text{p}\text{→π}{}^{\mathrm{?}}\text{∑}{}^{\mathrm{+}}\text{)}\text{(}\text{d}\text{σ}\text{d}\text{t)}{}_{\mathrm{t=0}}\text{(π}{}^{\mathrm{+}}\text{p}\text{→}\text{K}{}^{\mathrm{+}}\text{∑}{}^{\mathrm{+}}$

However, the slope for the positive reaction is about 19% steeper than that for the negative reaction.     

a2(1320)→π+π+π－过程的三体振幅分析

对a₂(1320)→π⁺π⁺π^－过程的衰变振幅进行张量分析,展示了如何得到三体衰变振幅.