Based on the naive quark model, we calculate angular distributions for heavy quarkonium decays into pN＊ （1440）, decuplet baryon pairs, and octet-decuplet baryon pairs. The general formulae of angular distributions ...Based on the naive quark model, we calculate angular distributions for heavy quarkonium decays into pN＊ （1440）, decuplet baryon pairs, and octet-decuplet baryon pairs. The general formulae of angular distributions are given explicitly. Quark mass effects on the violation of the helicity conservation and the prospect to look for them in J/ψ hadronic decays are discussed.展开更多
The aim of the Daya Bay reactor antineutrino experiment is to determine the neutrino mixing angle 13 with a sensitivity of 0.01 or better at 90% confidence level.In order to improve the position resolution of both the...The aim of the Daya Bay reactor antineutrino experiment is to determine the neutrino mixing angle 13 with a sensitivity of 0.01 or better at 90% confidence level.In order to improve the position resolution of both the positron interaction and the neutron capture,the inside of the antineutrino detectors should be as unreflecting as possible.A black matt fluorocarbon paint is coated on the inner surface of the detectors made of 304L stainless steel to meet the physical requirement.This paint is compatible with mineral oil,has low radioactivity,is easy to spray and fast curing at normal temperatures.The coating has excellent performance such as good adhesive force,uniformity,compact,scratch and wear resistance,and so on.It is the first application of such paint to large physical devices.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 10491303 and 10521003, the Knowledge Innovation Project of Chinese Academy of Sciences under Contract No U-612 （IHEP）.
文摘Based on the naive quark model, we calculate angular distributions for heavy quarkonium decays into pN＊ （1440）, decuplet baryon pairs, and octet-decuplet baryon pairs. The general formulae of angular distributions are given explicitly. Quark mass effects on the violation of the helicity conservation and the prospect to look for them in J/ψ hadronic decays are discussed.
基金supported in part by the Ministry of Science and Technology of China (Gramt No. 2006CB808100)supported by the National Natural Science Foundation of China(Grant No. 11005117)
文摘The aim of the Daya Bay reactor antineutrino experiment is to determine the neutrino mixing angle 13 with a sensitivity of 0.01 or better at 90% confidence level.In order to improve the position resolution of both the positron interaction and the neutron capture,the inside of the antineutrino detectors should be as unreflecting as possible.A black matt fluorocarbon paint is coated on the inner surface of the detectors made of 304L stainless steel to meet the physical requirement.This paint is compatible with mineral oil,has low radioactivity,is easy to spray and fast curing at normal temperatures.The coating has excellent performance such as good adhesive force,uniformity,compact,scratch and wear resistance,and so on.It is the first application of such paint to large physical devices.
