搜索结果: 1-15 共查到“理学 F0”相关记录17条 . 查询时间(0.046 秒)
北京谱仪Ⅲ实验a0和f0研究获进展（图）
北京 谱仪Ⅲ实验 a0 f0
2018/7/19
2018年7月11日，《物理评论快报》（Physical Review Letters）以“编辑推荐”的形式发表了北京谱仪Ⅲ (BESⅢ)实验的研究成果Observation of -f0(980) Mixing（Phys. Rev. Lett. 121, 022001 (2018)）。和f0(980)(简称a0和f0)是标量介子，其性质一直存在争议。除了被认为是夸克反夸克构成的普通介子态，在理论...
Long-term trends in f0 F2 over Grahamstown using Neural Networks
Solar activity magnetic activity
2015/9/25
Many authors have claimed to have found long-term trends in f0 F2 , or the lack thereof, for different stations. Such investigations usually involve gross assumptions about the variation of f0 F2 with...
The effects of f0 F2 variability on TEC prediction accuracy
ionopshere ionospheric modelling
2015/9/25
In this paper hourly daily F2-layer critical frequency data recorded at Rome and one minute daily TEC data recorded at Florence were used and the relevant variabiles were calculated. It was concluded ...
Variation of the feedback coefficient with R12 and the geographic latitude in 1-h ahead forecast of f0 F2
forecast feedback critical frequency
2015/9/25
The «prediction» and «forecast» of the critical frequency of the F 2 layer (f0 F2 ) is an important issue for frequency planning in short wave radio communications. In this context...
采用RACE方法克隆得到了凡纳滨对虾(Litopenaeus vannamei)的F0-ATP合酶b链基因的全长cDNA序列。生物信息学分析显示，该基因开放阅读框744 bp，编码248个氨基酸，分子量为28.2 kDa。Blast比对结果显示，克隆得到的cDNA序列所编码的氨基酸序列与海虱(Caligus clemensi) F0-ATP合酶β亚基的同源性为50%，与黑腹果蝇(Drosophil...
First observation of Bs -> J/psi f0(980) decays
First observation Bs -> J/psi f0(980) decays
2011/4/2
First observation of Bs -> J/psi f0(980) decays .
Study of a0(980)-f0(980) mixing at BES III and study of charged kappa at BES II
(980)-f0(980) charged kappa at BES II
2011/1/5
Recent BES results on light scalars are reported in this talk, including the observation of a charged k± decaying to K±p 0 with 5.8×107 J/y data at BES II and the directmeasurements of a00 (980)−...
In this proceeding, we propose to directly measure the a00(980)-f0(980) mixing in J/ψ→φ f0(980)→φa00(980) and χc1→π0φa00(980)→π0f0(980) with the upgraded Beijing Electron Positron Collider(BEPCII) wit...
No indication of f0(1370) in pi pi phase shift analyses
pion pion scattering scalar mesons glueball
2010/3/15
The scalar meson f_0(1370) - indicated in particular in the low energy p\bar p \to 3 body reactions - is a crucial element in certain schemes of the scalar meson spectroscopy including glueballs. The ...
We investigate the D0-D0 mixing through the doubly Cabibbo suppressed (DCS) channel D0→f0(980)K*0 and its charge conjugate channel, in which the K*0 meson is reconstructed in both K+π－ and KSπ0 final ...
用推广的矩分析方法讨论了过程J/ψ→X+f0(980),X→K+K－,f0(980)→π+π－.利用得到的矩表达式,可以确定玻色共振态X的自旋-宇称.
在J/ψ强子衰变过程中,伴随f0(975)产生的玻色共振态X,若衰变为一对正反赝标介子,它的自旋-宇称只能是产JPC=(奇)－－.这里给出了过程的角分布螺旋度形式,并就如何确认X为1－－或3－－介子作了讨论.认为北京谱仪在K+K－π+π－四叉道中见到的反冲f0(975)的共振态X1(1573)是一个可能的新共振态.
J/ψ→fJФ→ππK＋K－反应的各种一维角分布是否足以鉴别f0和f2?
J/ψ衰变 共振态 分波分析
2009/7/3
基于螺旋度分波分析公式,我们探讨在J ψ→fJ(θ1,1)、fJ→ππ(θ2 ,2 )、→K+ K-(θ3 ,3 )级联衰变过程中是否可以通过各种一维角分布投影鉴别出f0 和f2 共振态.结果表明,f0 和f2 可以同时给出完全相同的(θ1,1,θ2 ,2 )一维投影,但不能同时给出完全相同的(θ1,1,θ2 ,2 ,3 )一维投影.因此,要想保证从角分布的一维投影鉴别出f0...
J/ψ衰变中f0(975)的实验研究
标量介子 阈效应 自旋宇称 螺旋度
2009/6/3
本文基于北京正负电子对撞机(BEPC)上北京谱仪(BES)所收集到的国家自然科学基金资助.7.8×106J/ψ事例,系统研究了J/ψ→φπ+π－和J/ψ→ωπ+π－两个衰变道,给出了过程的分支比以及f0的位置和宽度参数,并对J/ψ→φf0,f0→π+π－过程的角分布进行了拟合,首次确定出该过程的螺旋度振幅比.