The parton rescattering effect on the charged hadron forward-backward multiplicity correlation in pp collisions at √s =200 GeV is studied by a parton and hadron cascade model, PACIAE, based on the PYTHIA model. The c...The parton rescattering effect on the charged hadron forward-backward multiplicity correlation in pp collisions at √s =200 GeV is studied by a parton and hadron cascade model, PACIAE, based on the PYTHIA model. The calculated multiplicity and pseudorapidity distribution of the final state charged hadrons are well compared with the experimental data. It is found that the final state charged hadron pseudorapidity distribution is different from the initial state charged partons. The parton rescattering effect on the charged hadron forward-backward multiplicity correlation increases with the increasing parton rescattering strength in the center pseudorapidity region （｜η｜ 〈 1）. However, this effect becomes weaker in the outer pseudorapidity region （｜η｜ 〉 1）.展开更多
Some of the possible decays of pp collisions at LHC experiment are considered. The vector bosons mediating in the electroweak interactions and right-handed leptons except neutrinos are assumed to be the most resultant...Some of the possible decays of pp collisions at LHC experiment are considered. The vector bosons mediating in the electroweak interactions and right-handed leptons except neutrinos are assumed to be the most resultant particles from the pp collisions. Neutrinos and anti-neutrinos will be observed when one-double electron charged vector bosons are the resultant particles. The charge conservation is thought to be the dominant factor of these decays. The amplitude transitions for Feynman diagram of these decays are written.展开更多
Revised August 2013 by O. Biebel （Ludwig-Maximilians-Universitat Munich, Germany）, D. de Florian （Dep. de Ffsica, FCEyN-UBA, Buenos Aires, Argentina）, D. Milstead （Fysikum, Stockholms Universitet, Sweden）, and A...Revised August 2013 by O. Biebel （Ludwig-Maximilians-Universitat Munich, Germany）, D. de Florian （Dep. de Ffsica, FCEyN-UBA, Buenos Aires, Argentina）, D. Milstead （Fysikum, Stockholms Universitet, Sweden）, and A. Vogt （Dep. of Mathematical Sciences, University of Liverpool, UK）.展开更多
We propose a forward method based on PYTHIA6.4 to study the jet properties in ultra-relativistic pp collisions.In the forward method,the partonic initial states are first generated with PYTHIA6.4 and then hadronized i...We propose a forward method based on PYTHIA6.4 to study the jet properties in ultra-relativistic pp collisions.In the forward method,the partonic initial states are first generated with PYTHIA6.4 and then hadronized in the Lund string fragmentation model,and finally the hadronic jets are constructed from the created hadrons.Jet properties calculated with the forward method for pp collisions at √s=7 TeV are comparable to those calculated with the usual anti-kt algorithm(backward method)in PYTHIA6.4.The comparison between the backward and forward methods may contribute to the understanding of the partonic origin of jets in the backward method.展开更多
Taking into account the effects of shadowing and jet quenching, the large transverse momentum distribution of K＋, π＋ and K＋/π＋ ratios at s = 200 GeV originating from resolved photoproduction processes is calcula...Taking into account the effects of shadowing and jet quenching, the large transverse momentum distribution of K＋, π＋ and K＋/π＋ ratios at s = 200 GeV originating from resolved photoproduction processes is calculated based on perturbative quantum chromodynamics. It is found that the contribution of K＋ and π＋ produced by photoproduction processes is evident. The K＋ /π＋ ratios in Au-Au collisions show an obvious enhancement compared with p p collisions. The numerical results indicate that the photoproduetion processes are good modification for kaon and pion production.展开更多
Complementary to the conventional experimental studies on N＊ from πN and γ（＊）N reactions, the e＋e-, pp and pp collisions can give novel insights into these N＊ resonances. While the e＋e- collisions through pro...Complementary to the conventional experimental studies on N＊ from πN and γ（＊）N reactions, the e＋e-, pp and pp collisions can give novel insights into these N＊ resonances. While the e＋e- collisions through production and decay of vector charmonium ψ provide a nice isospin filter for a simultaneously study of N＊, △＊, ∧＊, ∑＊ and 2＊, the pp collisions should be the best place for producing those △＊＋＋ with large coupling to p＋p though pp →nA＊＋＋ reaction, and the pp collisions should be the best place for looking for those N＊ with large coupling to σN.展开更多
基金supported by National Natural Science Foundation of China (Nos. 11047142, 10975062, 11075217, and 10705012)
文摘The parton rescattering effect on the charged hadron forward-backward multiplicity correlation in pp collisions at √s =200 GeV is studied by a parton and hadron cascade model, PACIAE, based on the PYTHIA model. The calculated multiplicity and pseudorapidity distribution of the final state charged hadrons are well compared with the experimental data. It is found that the final state charged hadron pseudorapidity distribution is different from the initial state charged partons. The parton rescattering effect on the charged hadron forward-backward multiplicity correlation increases with the increasing parton rescattering strength in the center pseudorapidity region （｜η｜ 〈 1）. However, this effect becomes weaker in the outer pseudorapidity region （｜η｜ 〉 1）.
文摘Some of the possible decays of pp collisions at LHC experiment are considered. The vector bosons mediating in the electroweak interactions and right-handed leptons except neutrinos are assumed to be the most resultant particles from the pp collisions. Neutrinos and anti-neutrinos will be observed when one-double electron charged vector bosons are the resultant particles. The charge conservation is thought to be the dominant factor of these decays. The amplitude transitions for Feynman diagram of these decays are written.
文摘Revised August 2013 by O. Biebel （Ludwig-Maximilians-Universitat Munich, Germany）, D. de Florian （Dep. de Ffsica, FCEyN-UBA, Buenos Aires, Argentina）, D. Milstead （Fysikum, Stockholms Universitet, Sweden）, and A. Vogt （Dep. of Mathematical Sciences, University of Liverpool, UK）.
基金Supported by the National Natural Science Foundation of China(11477130,11775094)the 111 project of the foreign expert bureau of China+2 种基金the financial support from Suranaree University of Technology and the Office of the Higher Education Commission under the NRU project of Thailandthe financial support from Key Laboratory of Quark and Lepton Physics in Central China Normal University(QLPL201805)the Continuous Basic Scientific Research Project(WDJC-2019-13)
文摘We propose a forward method based on PYTHIA6.4 to study the jet properties in ultra-relativistic pp collisions.In the forward method,the partonic initial states are first generated with PYTHIA6.4 and then hadronized in the Lund string fragmentation model,and finally the hadronic jets are constructed from the created hadrons.Jet properties calculated with the forward method for pp collisions at √s=7 TeV are comparable to those calculated with the usual anti-kt algorithm(backward method)in PYTHIA6.4.The comparison between the backward and forward methods may contribute to the understanding of the partonic origin of jets in the backward method.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11065010 and 11465021
文摘Taking into account the effects of shadowing and jet quenching, the large transverse momentum distribution of K＋, π＋ and K＋/π＋ ratios at s = 200 GeV originating from resolved photoproduction processes is calculated based on perturbative quantum chromodynamics. It is found that the contribution of K＋ and π＋ produced by photoproduction processes is evident. The K＋ /π＋ ratios in Au-Au collisions show an obvious enhancement compared with p p collisions. The numerical results indicate that the photoproduetion processes are good modification for kaon and pion production.
基金Supported by National Natural Science Foundation of China (10875133, 10821063)Chinese Academy of Sciences (KJCX3-SYW-N2)Ministry of Science and Technology of China (2009CB825200)
文摘Complementary to the conventional experimental studies on N＊ from πN and γ（＊）N reactions, the e＋e-, pp and pp collisions can give novel insights into these N＊ resonances. While the e＋e- collisions through production and decay of vector charmonium ψ provide a nice isospin filter for a simultaneously study of N＊, △＊, ∧＊, ∑＊ and 2＊, the pp collisions should be the best place for producing those △＊＋＋ with large coupling to p＋p though pp →nA＊＋＋ reaction, and the pp collisions should be the best place for looking for those N＊ with large coupling to σN.
