The charge readout of a liquid xenon(LXe)detector via proportional scintillation in the liquid phase was first realized by the Waseda group 40 years ago,but the technical challenges involved were overwhelming.Although...The charge readout of a liquid xenon(LXe)detector via proportional scintillation in the liquid phase was first realized by the Waseda group 40 years ago,but the technical challenges involved were overwhelming.Although the tests were successful,this method was finally discarded and eventually nearly forgotten.Currently,this approach is not considered for large LXe dark matter detectors.Instead,the dual-phase technology was selected despite many limitations and challenges.In two independent studies,two groups from Columbia University and Shanghai Jiao Tong University reevaluated proportional scintillation in the liquid phase.Both studies established the merits for very large LXe detectors,but the Columbia group also encountered apparent limitations,namely the shadowing of the light by the anode wires,and a dependence of the pulse shape on the drift path of the electrons in the anode region.The differences between the two studies,however,are not intrinsic to the technique,but a direct consequence of the chosen geometry.Taking the geometrical differences into account,the results match without ambiguity.They also agree with the original results from the Waseda group.展开更多
The structure and stability of the compounds MRg^(+)and MRg F(Rg=Ar,Kr,and Xe;M=Co,Rh,and Ir)were investigated using the B3 LYP,MP2,MP4(SDQ)and CCSD(T)methods.We reported the geometry,vibrational frequencies and therm...The structure and stability of the compounds MRg^(+)and MRg F(Rg=Ar,Kr,and Xe;M=Co,Rh,and Ir)were investigated using the B3 LYP,MP2,MP4(SDQ)and CCSD(T)methods.We reported the geometry,vibrational frequencies and thermodynamics properties of these compounds.A series of theoretical methods on the basis of wavefunction analysis,including natural bond orbitals,atoms in molecules,electron localization function,and energy decomposition analysis,were performed to explore bonding nature of the M-Rg and Rg-F bonds.These bonds are mainly noncovalent,the metal weakly interacts with Rg in MRg^(+),but their interaction is much stronger in MRg F.The neutral molecule MRg F can be well described by the Lewis structure[MRg]^(+)F^(-).展开更多
基金supported by a Grant from the Ministry of Science and Technology of China(No.2016YFA0400301)。
文摘The charge readout of a liquid xenon(LXe)detector via proportional scintillation in the liquid phase was first realized by the Waseda group 40 years ago,but the technical challenges involved were overwhelming.Although the tests were successful,this method was finally discarded and eventually nearly forgotten.Currently,this approach is not considered for large LXe dark matter detectors.Instead,the dual-phase technology was selected despite many limitations and challenges.In two independent studies,two groups from Columbia University and Shanghai Jiao Tong University reevaluated proportional scintillation in the liquid phase.Both studies established the merits for very large LXe detectors,but the Columbia group also encountered apparent limitations,namely the shadowing of the light by the anode wires,and a dependence of the pulse shape on the drift path of the electrons in the anode region.The differences between the two studies,however,are not intrinsic to the technique,but a direct consequence of the chosen geometry.Taking the geometrical differences into account,the results match without ambiguity.They also agree with the original results from the Waseda group.
文摘The structure and stability of the compounds MRg^(+)and MRg F(Rg=Ar,Kr,and Xe;M=Co,Rh,and Ir)were investigated using the B3 LYP,MP2,MP4(SDQ)and CCSD(T)methods.We reported the geometry,vibrational frequencies and thermodynamics properties of these compounds.A series of theoretical methods on the basis of wavefunction analysis,including natural bond orbitals,atoms in molecules,electron localization function,and energy decomposition analysis,were performed to explore bonding nature of the M-Rg and Rg-F bonds.These bonds are mainly noncovalent,the metal weakly interacts with Rg in MRg^(+),but their interaction is much stronger in MRg F.The neutral molecule MRg F can be well described by the Lewis structure[MRg]^(+)F^(-).