The Higgs triplet model （HTM） predicts the existence of a pair of doubly charged Higgs bosons H±±. Single production of H±± via e7 collision at the next generation e＋ e- International Linear Col...The Higgs triplet model （HTM） predicts the existence of a pair of doubly charged Higgs bosons H±±. Single production of H±± via e7 collision at the next generation e＋ e- International Linear Collider （ILC） and the Large Hadron electron Collider （LHeC） is considered. The numerical results show that the production cross sections are very sensitive to the neutrino oscillation parameters. Their values for the inverted hierarchy mass spectrum are larger than those for the normal hierarchy mass spectrum at these two kinds of collider experiments. With reasonable values of the relevant free parameters, the possible signals of the doubly charged Higgs bosons predicted by the HTM might be detected in future ILC experiments.展开更多
Ion-pair dissociation is an important molecular process and frequently happens when the target molecule is pumped to its electronically superexcited states. In contrast to the experimental studies of photoexcitation i...Ion-pair dissociation is an important molecular process and frequently happens when the target molecule is pumped to its electronically superexcited states. In contrast to the experimental studies of photoexcitation ion-pair dissociation, there are some experimental challenges in the electron-impact ion-pair dissociation study, in particular, on determination of the energetic threshold. Here we report an experimental development for the ion-pair dissociation study by using the monochromized electron impacts. As an example, the threshold of BrCN→Br^-+CN^+ is determined as 13.78 eV according to the appearance energy of CN^+ signals, meanwhile, the time-sliced ion velocity image of CN^+ is recorded at 16.09 eV and indicates an anisotropic distribution of the CN^+ momentum.展开更多
In the framework of topcolor-assisted technicolor （TC2） model, there exist tree-level flavor-changing （FC） couplings, which can result in the loop-level FC coupling tcg. Such tcg coupling can contribute significan...In the framework of topcolor-assisted technicolor （TC2） model, there exist tree-level flavor-changing （FC） couplings, which can result in the loop-level FC coupling tcg. Such tcg coupling can contribute significant clues at the forthcoming Large Hadron Collider （LHC） experiments. In this paper, based on the TC2 model, we study some single t-quark production processes involving tcg coupling at the Tevatron and LHC： pp（pp） → tq （q = u, d, s）, tg. We calculate the cross sections of these processes. The results show that the cross sections at the Tevatron are too small to observe the signal, but at the LHC it can reach a few pb. With the high luminosity, the LHC has considerable capability to find the single t-quark signal produced via some FC processes involving coupling tcg. On the other hand, these processes can also provide some valuable information of the coupling tcg with detailed study of the processes and furthermore provide the reliable evidence to test the TC2 model展开更多
In the context of the top-color-assisted technicolor （TC2） model, the flavor-changing neutral-current （FCNC） interaction induced by the top-higgs （hOt） are predicted at tree level. We study the relevant processe...In the context of the top-color-assisted technicolor （TC2） model, the flavor-changing neutral-current （FCNC） interaction induced by the top-higgs （hOt） are predicted at tree level. We study the relevant processes of e＋e-（γγ）→tcht0 at the International Linear Collider （ILC）. It is found that these rare processes production rates can be enhanced significantly in the TC2 model. Especially for the process γγ→tcht0, the total cross section will reach a few fb in the reasonable parameter space. We also calculate the distributions of transverse momenta, pseudo-rapid and invariant mass of the top-higgs. In view of the main decay modes of top-higgs for mho 〈 2mr, we find that there will be several hundreds FCNC events produced at the ILC with annually integral luminosity of 500 fb-1. Due to the clean background, such FCNC signals can possibly be detected at the ILC.展开更多
The BEPCⅡis the upgrade project of the Beijing Electron Positron Collider(BEPC).According to the BEPCⅡdouble ring design scheme,a new ring will be added in the existing BEPC tunnel.The machine will provide electron ...The BEPCⅡis the upgrade project of the Beijing Electron Positron Collider(BEPC).According to the BEPCⅡdouble ring design scheme,a new ring will be added in the existing BEPC tunnel.The machine will provide electron and positron beams with an energy range from 1.0GeV to 2.1GeV for high energy physics research,and an electron beam of 2.SGeV,250mA for synchrotron radiation.So actually there are three storage rings for the BEPCⅡmachine.Due to the limited space of the existing BEPC tunnel and the requirement of high luminosity,the antechamber type vacuum chamber is used,that makes the BEPCⅡmagnets'design and fabrication very difficult.In the paper the general features of the design and fabrication of several kinds of main magnets for the BEPCⅡstorage ring and its interaction region are introduced.And the magnetic field measurement results are presented.展开更多
In this paper,the average dose level is introduced in an environment and area when BEPCⅡis debugged. The typical dose graphs are offered when the electronic storage ring is debugged and works in the synchrotron radia...In this paper,the average dose level is introduced in an environment and area when BEPCⅡis debugged. The typical dose graphs are offered when the electronic storage ring is debugged and works in the synchrotron radiation mode.At the same time,some suggestions about radiation protection are presented.All the data indicate that the main and local part shielding satisfy the need and attain the design target.展开更多
We study prompt hadroproduction of the charged bottomonium-like states Zb± （10610） and Zb±（10650）, and the charged eharmonium-like states Zc± （3900） and Zc± （4020）, at the Tevatron and the ...We study prompt hadroproduction of the charged bottomonium-like states Zb± （10610） and Zb±（10650）, and the charged eharmonium-like states Zc± （3900） and Zc± （4020）, at the Tevatron and the LHC, provided that these states are S-wave hadronic molecules. Using two Monte Carlo event generators, Herwig and Pythia, to simulate the production of heavy meson pairs, we derive an order-of-magnitude estimate of the production rates for these four particles. Our estimates yield a cross section at the nb level for the Zb（10610） and Zb（10650）. The results for the Zc（3900） and Zc （4020） are larger by a factor of 2~30. These cross sections are large enough to be observed, and measurements at hadron colliders in the future will supplement the study using electron-positron collisions, and therefore allow to explore the mysterious nature of these exotic states.展开更多
We derive cubic and quartic couplings of the Higgs singlet extension of the SM and the two Higgs doublet model. We also examine the number of CP violated couplings in a model with n Higgs doublet model and a model wit...We derive cubic and quartic couplings of the Higgs singlet extension of the SM and the two Higgs doublet model. We also examine the number of CP violated couplings in a model with n Higgs doublet model and a model with ns Higgs singlets and ndHiggs doublets. We conclude that in order to reconstruct the Higgs potential with multi Higgs fields at the LHC and future colliders, to detect the cubic/quartic couplings is necessary.展开更多
In this paper,we investigate the production of a pair of doubly charged leptons associated with a gauge boson V(γ or Z) at future linear colliders via e^+e^-and γγ collisions.The numerical results show that the pos...In this paper,we investigate the production of a pair of doubly charged leptons associated with a gauge boson V(γ or Z) at future linear colliders via e^+e^-and γγ collisions.The numerical results show that the possible signals of the doubly charged leptons may be detected via the processes e^+e~→VX^(++)X^(--)and γγ→VX^(++)X^(--)at future ILC or CLIC experiments.展开更多
In the framework of the littlest Higgs model with T-parity （LHT）, we study the top quark spin correlation and polarization at the International Linear Collider （ILC）. We find that the top quark polarization asymme...In the framework of the littlest Higgs model with T-parity （LHT）, we study the top quark spin correlation and polarization at the International Linear Collider （ILC）. We find that the top quark polarization asymmetry δPt and the left-right asymmetry δALR can respectively reach -35% and -37.5% for s = 500 GeV and s = 1000 GeV via e＋e- collision, which can reach the observable level at the ILC. By contrast, the spin correlation δC is smaller. The correlation behaviors of these observables at the e＋e- collision and the yy, collision will be helpful to distinguish different models and test the LHT model at the ILC.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.10975067the Specialized Research Fund for the Doctoral Program of Higher Education(SRFDP) under Grant No.200801650002
文摘The Higgs triplet model （HTM） predicts the existence of a pair of doubly charged Higgs bosons H±±. Single production of H±± via e7 collision at the next generation e＋ e- International Linear Collider （ILC） and the Large Hadron electron Collider （LHeC） is considered. The numerical results show that the production cross sections are very sensitive to the neutrino oscillation parameters. Their values for the inverted hierarchy mass spectrum are larger than those for the normal hierarchy mass spectrum at these two kinds of collider experiments. With reasonable values of the relevant free parameters, the possible signals of the doubly charged Higgs bosons predicted by the HTM might be detected in future ILC experiments.
基金supported by the National Natural Science Foundation of China (No.21625301)
文摘Ion-pair dissociation is an important molecular process and frequently happens when the target molecule is pumped to its electronically superexcited states. In contrast to the experimental studies of photoexcitation ion-pair dissociation, there are some experimental challenges in the electron-impact ion-pair dissociation study, in particular, on determination of the energetic threshold. Here we report an experimental development for the ion-pair dissociation study by using the monochromized electron impacts. As an example, the threshold of BrCN→Br^-+CN^+ is determined as 13.78 eV according to the appearance energy of CN^+ signals, meanwhile, the time-sliced ion velocity image of CN^+ is recorded at 16.09 eV and indicates an anisotropic distribution of the CN^+ momentum.
基金The project supported by National Natural Science Foundation of China under Grant Nos.10375017,10575029,and 10575052
文摘In the framework of topcolor-assisted technicolor （TC2） model, there exist tree-level flavor-changing （FC） couplings, which can result in the loop-level FC coupling tcg. Such tcg coupling can contribute significant clues at the forthcoming Large Hadron Collider （LHC） experiments. In this paper, based on the TC2 model, we study some single t-quark production processes involving tcg coupling at the Tevatron and LHC： pp（pp） → tq （q = u, d, s）, tg. We calculate the cross sections of these processes. The results show that the cross sections at the Tevatron are too small to observe the signal, but at the LHC it can reach a few pb. With the high luminosity, the LHC has considerable capability to find the single t-quark signal produced via some FC processes involving coupling tcg. On the other hand, these processes can also provide some valuable information of the coupling tcg with detailed study of the processes and furthermore provide the reliable evidence to test the TC2 model
基金Supported in part by the National Natural Science Foundation of China (NNSFC) under Grant Nos.10975047,10979008,and 10775039 Specialized Research Fund for the Doctoral Program of Higher Education under Grant No.20094104110001
文摘In the context of the top-color-assisted technicolor （TC2） model, the flavor-changing neutral-current （FCNC） interaction induced by the top-higgs （hOt） are predicted at tree level. We study the relevant processes of e＋e-（γγ）→tcht0 at the International Linear Collider （ILC）. It is found that these rare processes production rates can be enhanced significantly in the TC2 model. Especially for the process γγ→tcht0, the total cross section will reach a few fb in the reasonable parameter space. We also calculate the distributions of transverse momenta, pseudo-rapid and invariant mass of the top-higgs. In view of the main decay modes of top-higgs for mho 〈 2mr, we find that there will be several hundreds FCNC events produced at the ILC with annually integral luminosity of 500 fb-1. Due to the clean background, such FCNC signals can possibly be detected at the ILC.
文摘The BEPCⅡis the upgrade project of the Beijing Electron Positron Collider(BEPC).According to the BEPCⅡdouble ring design scheme,a new ring will be added in the existing BEPC tunnel.The machine will provide electron and positron beams with an energy range from 1.0GeV to 2.1GeV for high energy physics research,and an electron beam of 2.SGeV,250mA for synchrotron radiation.So actually there are three storage rings for the BEPCⅡmachine.Due to the limited space of the existing BEPC tunnel and the requirement of high luminosity,the antechamber type vacuum chamber is used,that makes the BEPCⅡmagnets'design and fabrication very difficult.In the paper the general features of the design and fabrication of several kinds of main magnets for the BEPCⅡstorage ring and its interaction region are introduced.And the magnetic field measurement results are presented.
文摘In this paper,the average dose level is introduced in an environment and area when BEPCⅡis debugged. The typical dose graphs are offered when the electronic storage ring is debugged and works in the synchrotron radiation mode.At the same time,some suggestions about radiation protection are presented.All the data indicate that the main and local part shielding satisfy the need and attain the design target.
基金Supported in part by the DFG and the NSFC through funds provided to the Sino-German CRC 110 ＂Symmetries and the Emergence of Structure in QCD＂, and by the NSFC under Grant No. 11165005
文摘We study prompt hadroproduction of the charged bottomonium-like states Zb± （10610） and Zb±（10650）, and the charged eharmonium-like states Zc± （3900） and Zc± （4020）, at the Tevatron and the LHC, provided that these states are S-wave hadronic molecules. Using two Monte Carlo event generators, Herwig and Pythia, to simulate the production of heavy meson pairs, we derive an order-of-magnitude estimate of the production rates for these four particles. Our estimates yield a cross section at the nb level for the Zb（10610） and Zb（10650）. The results for the Zc（3900） and Zc （4020） are larger by a factor of 2~30. These cross sections are large enough to be observed, and measurements at hadron colliders in the future will supplement the study using electron-positron collisions, and therefore allow to explore the mysterious nature of these exotic states.
基金Supported by the Natural Science Foundation of China under Grant Nos.11175251 and 11575005
文摘We derive cubic and quartic couplings of the Higgs singlet extension of the SM and the two Higgs doublet model. We also examine the number of CP violated couplings in a model with n Higgs doublet model and a model with ns Higgs singlets and ndHiggs doublets. We conclude that in order to reconstruct the Higgs potential with multi Higgs fields at the LHC and future colliders, to detect the cubic/quartic couplings is necessary.
基金Supported in part by the National Natural Science Foundation of China under Grants Nos.11275088,11205023,11375248the Program for Liaoning Excellent Talents in University under Grant No.LJQ2014135
文摘In this paper,we investigate the production of a pair of doubly charged leptons associated with a gauge boson V(γ or Z) at future linear colliders via e^+e^-and γγ collisions.The numerical results show that the possible signals of the doubly charged leptons may be detected via the processes e^+e~→VX^(++)X^(--)and γγ→VX^(++)X^(--)at future ILC or CLIC experiments.
文摘In the framework of the littlest Higgs model with T-parity （LHT）, we study the top quark spin correlation and polarization at the International Linear Collider （ILC）. We find that the top quark polarization asymmetry δPt and the left-right asymmetry δALR can respectively reach -35% and -37.5% for s = 500 GeV and s = 1000 GeV via e＋e- collision, which can reach the observable level at the ILC. By contrast, the spin correlation δC is smaller. The correlation behaviors of these observables at the e＋e- collision and the yy, collision will be helpful to distinguish different models and test the LHT model at the ILC.
