Based on analysis of scattering matrix S, and its properties such as analyticity, unitarity, Lorentz invariance, and crossing symmetry relation, the Regge theory was proposed to describe hadron-hadron scattering at hi...Based on analysis of scattering matrix S, and its properties such as analyticity, unitarity, Lorentz invariance, and crossing symmetry relation, the Regge theory was proposed to describe hadron-hadron scattering at high energies before the advent of QCD, and correspondingly a Reggeon concept was born as a mediator of strongly interaction. This theory serves as a successful approach and has explained a great number of experimental data successfully, which proves that the Regge theory can be regarded as a basic theory of hadron interaction at high energies and its validity in many applications. However, as new experimental data come out, we have some difficulties in explaining the data. The new experimental total cross section violates the predictions of Regge theory, which shows that Regge formalism is limited in its applications to high energy data. To understand new experimental measurements, a new exchange theory was consequently born and its mediator is called Pomeron, which has vacuum quantum numbers. The new theory named as Pomeron exchange theory which reproduces the new experimental data of diffractive processes successfully. There are two exchange mediators： Reggeon and Pomeron. Reggeon exchange theory can only produce data at the relatively lower energy region, while Pomeron exchange theory fits the data only at higher-energy region, separately. In order to explain the data in the whole energy region, we propose a Reggeon-Pomeron model to describe high-energy hadron- hadron scattering and other diffractive processes. Although the Reggeon-Pomeron model is successful in describing high-energy hadron-hadron interaction in the whole energy region, it is a phenomenological model. After the advent of QCD, people try to reveal the mystery of the phenomenological theory from QCD since hadron-hadron processes is a strong interaction, which is believed to be described by QCD. According to this point of view, we study the QCD nature of Reggeon and Pomeron. We claim that the Reggeon exchange is an exchange of multigluon,the color singlet gluon bound state. In particular, the Pomeron could be a Reggeized tensor glueball ξ（2230） with mass of 2.23 GeV, quantum numbers I^G, J^PC = 0^＋, 2^＋＋ and decay width of about 100 MeV. The glueball exchange theory reproduces data quite well. Accordingly, we believe that the Odderon, consisting of three Reggeized gluons, and predicted by QCD, should also contribute to hadron-hadron scattering and many other diffractive processes. We search for the Odderon by studying pp and pp elastic scatterings at high energies. Our investigations on the differential cross section dσ/ dt of hadron-hadron scattering at various energies and comparisons with experimental data show that the Odderon plays an essential role in fitting to data. Therefore, we suggest that the measurements should be urgently done in order to confirm the existences of the Odderon and to test QCD.展开更多
Exotic hadrons,beyond the conventional quark model,have been discovered over the past two decades.Investigating these states can lead to a deeper understanding of the nonperturbative dynamics of the strong interaction...Exotic hadrons,beyond the conventional quark model,have been discovered over the past two decades.Investigating these states can lead to a deeper understanding of the nonperturbative dynamics of the strong interaction.In this review,we focus on the production of exotic hadrons in pp,PP^(-),and nuclear collisions.Experimental observations of light and hypernuclei as prototypes of hadronic molecules in heavy-ion collisions are also briefly discussed.展开更多
We propose that the X(3915)observed in the J/w channel is the same state as the Xe2(3930),and the X(3960),observed in the D,D,channel,is an S-wave D,D,hadronic molecule.In addition,the jpC=0^(++)component in the B^(+)...We propose that the X(3915)observed in the J/w channel is the same state as the Xe2(3930),and the X(3960),observed in the D,D,channel,is an S-wave D,D,hadronic molecule.In addition,the jpC=0^(++)component in the B^(+)→D^(+)D K^(+)assigned to the X(3915)in the current Review of Particle Physics has the same origin as the X(3960),which has a mass around 3.94 GeV.To check the proposal,the available data in the DD and D,D,channels from both B decays andγγfusion reaction are analyzed considering both the DD-D,D,-D'D'-D,D,coupled channels with o^(++)and a 2^(++)state introduced additionally.It is found that all the data in different processes can be simultaneously well reproduced,and the coupled-channel dynamics produce four hidden-charm scalar molecular states with masses around 3.73,3.94,3.99 and 4.23 Gev,respectively.The results may deepen our understanding of the spectrum of charmonia as well as of the interactions between charmed hadrons.展开更多
Various measures of event-by-event net charge and charge ratio fluctuations in pp and AA collisions at RHIC and LHC energies are studied using the different Monte Carlo generators: URQMD, HIJING and HIJING/ and the re...Various measures of event-by-event net charge and charge ratio fluctuations in pp and AA collisions at RHIC and LHC energies are studied using the different Monte Carlo generators: URQMD, HIJING and HIJING/ and the results are compared with the predictions for the independent emission, hadron gas and QGP phase. Values of the D-measures are observed to exhibit significant energy dependence for both pp and AA data. Furthermore, there is essentially no significant difference in the values of the D-measures predicted by the various Monte Carlo codes used in the present study. A slight centrality dependence of the D-measures in terms of net charge fluctuations is observed in the case of Au-Au data at 200A GeV/c. These findings, thus, suggest that a difference in the D-measures for pp and AA collisions either the re-scattering effect plays a predominant role or there might be some new physics present in these collisions.展开更多
The practice of using the direct ionization radiation (electrons, protons, antiprotons, pions, ions, etc) or of the indirect ionization radiation (photons, neutrons, etc) in economy and social life has led to the intr...The practice of using the direct ionization radiation (electrons, protons, antiprotons, pions, ions, etc) or of the indirect ionization radiation (photons, neutrons, etc) in economy and social life has led to the introduction of the absorbed dose magnitude (ICRU 1953) defined as the energy absorbed per mass unit of the irradiated substance. This is a fundamental magnitude valid for any type of ionizing radiation, any irradiated material and any radiation energy. In case of clinical hadron beams generated by conventional accelerators or those controlled by lasers, IAEA TRS 398 recommends the absorbed dose to water. This may be determined employing the calorimeter method with water or graphite, chemical method, fluence based measurements as Faraday cups or activation measurements, and the ionization chamber method. In this paper the selected method was the thimble air filled ionization chamber method for determination of absorbed dose to water.展开更多
The following article has been retracted due to the investigation of complaints received against it. Mr. Mohammadali Ghorbani (corresponding author and also the last author) cheated the author’s name: Alireza Heidari...The following article has been retracted due to the investigation of complaints received against it. Mr. Mohammadali Ghorbani (corresponding author and also the last author) cheated the author’s name: Alireza Heidari. The scientific community takes a very strong view on this matter and we treat all unethical behavior such as plagiarism seriously. This paper published in Vol.3 No.2, 208-213, 2012, has been removed from this site.展开更多
Two near-threshold peaking structures with spin-parities of J^(PC)=0^(++)were recently discovered by the LHCb Collaboration in the invariant mass distribution of the decay process B^(+)→D_(s)^(+)D_(s)^(-)K^(+).In our...Two near-threshold peaking structures with spin-parities of J^(PC)=0^(++)were recently discovered by the LHCb Collaboration in the invariant mass distribution of the decay process B^(+)→D_(s)^(+)D_(s)^(-)K^(+).In our study,we employed a coupled-channel model to fit the experimental results published by the LHCb Collaboration,simultaneously fitting the model to the invariant mass distributions of,MD_(s)+D_(s)^(-),M_(D)_(S)^(+)K^(+)and.We utilized a coupled-channel model to search for the poles of and.The determination of the poles is meaningful in itself,and it also lays a foundation for future research on and.Upon turning off the coupled-channel and performing another fit,we observed a change in the fitting quality,and the effect was almost entirely due to the peak of.Therefore,we suggest that may not be a kinematic effect.展开更多
We present the first lattice result of the near threshold Λ_(c)Λ_(c)scattering with I(J^(P)) = 0(0^(+)). The calculation is performed on two N_(f)= 2 + 1 Wilson-Clover ensembles with pion mass m_(π)~ 303 MeV and la...We present the first lattice result of the near threshold Λ_(c)Λ_(c)scattering with I(J^(P)) = 0(0^(+)). The calculation is performed on two N_(f)= 2 + 1 Wilson-Clover ensembles with pion mass m_(π)~ 303 MeV and lattice spacing a = 0.07746 fm. Lüscher's finite volume method is utilized to extract the scattering parameters from the finitevolume spectrum. The coupled channel Ξ_(cc)N is ignored in the scattering analysis based on the observation that the energy levels computed from the Λ_(c)Λ_(c)and Ξ_(cc) N operators do not mix. The Σ_(c)Σ_(c) channel is not included either since the energy range explored in this study is well below its threshold. Our results indicate that the interaction in the Λ_(c)Λ_(c)single channel is repulsive, and the scattering length is determined to be a_(0)=-0.21(4)(8) fm, where the first error is statistical and the second is systematic.展开更多
Recently,the LHCb experimental group found an exotic state T_(cc)^(+) from the pp→D^(0)D^(0)π^(+)+X process.A key question is whether it is just a molecule or may have a confined tetraquark ingredient.To investigate...Recently,the LHCb experimental group found an exotic state T_(cc)^(+) from the pp→D^(0)D^(0)π^(+)+X process.A key question is whether it is just a molecule or may have a confined tetraquark ingredient.To investigate this,different methods were used,including a two-channel(D^(∗)+D^(0) and D^(∗)0D^(+))K-matrix unitarization and a single-channel Flatté-like parametrization method analyzed utilizing the pole counting rule and spectral density function sum rule.These analyses demonstrated that T_(cc)^(+) is a molecular state,although the possibility that there may exist an elementary ingredient cannot be excluded,according to an approximate analysis of its production rate.展开更多
基金supported by National Natural Science Foundation of China under Grant Nos.10565001 and 10647002the Natural Science Foundation of Guangxi under Grant Nos.0481030,0575020,and 0565001
文摘Based on analysis of scattering matrix S, and its properties such as analyticity, unitarity, Lorentz invariance, and crossing symmetry relation, the Regge theory was proposed to describe hadron-hadron scattering at high energies before the advent of QCD, and correspondingly a Reggeon concept was born as a mediator of strongly interaction. This theory serves as a successful approach and has explained a great number of experimental data successfully, which proves that the Regge theory can be regarded as a basic theory of hadron interaction at high energies and its validity in many applications. However, as new experimental data come out, we have some difficulties in explaining the data. The new experimental total cross section violates the predictions of Regge theory, which shows that Regge formalism is limited in its applications to high energy data. To understand new experimental measurements, a new exchange theory was consequently born and its mediator is called Pomeron, which has vacuum quantum numbers. The new theory named as Pomeron exchange theory which reproduces the new experimental data of diffractive processes successfully. There are two exchange mediators： Reggeon and Pomeron. Reggeon exchange theory can only produce data at the relatively lower energy region, while Pomeron exchange theory fits the data only at higher-energy region, separately. In order to explain the data in the whole energy region, we propose a Reggeon-Pomeron model to describe high-energy hadron- hadron scattering and other diffractive processes. Although the Reggeon-Pomeron model is successful in describing high-energy hadron-hadron interaction in the whole energy region, it is a phenomenological model. After the advent of QCD, people try to reveal the mystery of the phenomenological theory from QCD since hadron-hadron processes is a strong interaction, which is believed to be described by QCD. According to this point of view, we study the QCD nature of Reggeon and Pomeron. We claim that the Reggeon exchange is an exchange of multigluon,the color singlet gluon bound state. In particular, the Pomeron could be a Reggeized tensor glueball ξ（2230） with mass of 2.23 GeV, quantum numbers I^G, J^PC = 0^＋, 2^＋＋ and decay width of about 100 MeV. The glueball exchange theory reproduces data quite well. Accordingly, we believe that the Odderon, consisting of three Reggeized gluons, and predicted by QCD, should also contribute to hadron-hadron scattering and many other diffractive processes. We search for the Odderon by studying pp and pp elastic scatterings at high energies. Our investigations on the differential cross section dσ/ dt of hadron-hadron scattering at various energies and comparisons with experimental data show that the Odderon plays an essential role in fitting to data. Therefore, we suggest that the measurements should be urgently done in order to confirm the existences of the Odderon and to test QCD.
基金supported in part by the National Key Research and Development Program of China(Nos.2022YFA1604900,2023YFA1606703,2024YFA1610503)the National Natural Science Foundation of China(Nos.12025501,12147101,12375073,12125507,12361141819,12047503,12175239,12221005)the Chinese Academy of Sciences(Nos.XDB34000000 and YSBR-101)。
文摘Exotic hadrons,beyond the conventional quark model,have been discovered over the past two decades.Investigating these states can lead to a deeper understanding of the nonperturbative dynamics of the strong interaction.In this review,we focus on the production of exotic hadrons in pp,PP^(-),and nuclear collisions.Experimental observations of light and hypernuclei as prototypes of hadronic molecules in heavy-ion collisions are also briefly discussed.
基金supported by the Spanish Ministerio de Ciencia e Innovación(MICINN)and the European Regional Development Fund(ERDF)under Contract PID2020-112777 GB-I00by the EU STRONG-2020 Project under the Program H2020-INFRAIA-2018–1 with Grant Agreement No.824093+4 种基金by Generalitat Valenciana under Contract PROMETEO/2020/023by the Chinese Academy of Sciences under Grant No.XDB34030000by the National Natural Science Foundation of China(NSFC)under Grants No.12125507,No.11835015,No.12047503,and No.11961141012by the NSFC and the Deutsche Forschungsgemeinschaft(DFG)through the funds provided to the Sino-German Collaborative Research Center TRR110“Symmetries and the Emergence of Structure in QCD”(NSFC Grant No.12070131001,DFG Project-ID 196253076)M.A.is supported by Generalitat Valenciana under Grant No.CIDEGENT/2020/002.
文摘We propose that the X(3915)observed in the J/w channel is the same state as the Xe2(3930),and the X(3960),observed in the D,D,channel,is an S-wave D,D,hadronic molecule.In addition,the jpC=0^(++)component in the B^(+)→D^(+)D K^(+)assigned to the X(3915)in the current Review of Particle Physics has the same origin as the X(3960),which has a mass around 3.94 GeV.To check the proposal,the available data in the DD and D,D,channels from both B decays andγγfusion reaction are analyzed considering both the DD-D,D,-D'D'-D,D,coupled channels with o^(++)and a 2^(++)state introduced additionally.It is found that all the data in different processes can be simultaneously well reproduced,and the coupled-channel dynamics produce four hidden-charm scalar molecular states with masses around 3.73,3.94,3.99 and 4.23 Gev,respectively.The results may deepen our understanding of the spectrum of charmonia as well as of the interactions between charmed hadrons.
文摘Various measures of event-by-event net charge and charge ratio fluctuations in pp and AA collisions at RHIC and LHC energies are studied using the different Monte Carlo generators: URQMD, HIJING and HIJING/ and the results are compared with the predictions for the independent emission, hadron gas and QGP phase. Values of the D-measures are observed to exhibit significant energy dependence for both pp and AA data. Furthermore, there is essentially no significant difference in the values of the D-measures predicted by the various Monte Carlo codes used in the present study. A slight centrality dependence of the D-measures in terms of net charge fluctuations is observed in the case of Au-Au data at 200A GeV/c. These findings, thus, suggest that a difference in the D-measures for pp and AA collisions either the re-scattering effect plays a predominant role or there might be some new physics present in these collisions.
基金supported in part by the Chinese Academy of Sciences(CAS)under Grant No.XDB34030000 and No.QYZDBSSW-SYS013the National Natural Science Foundation of China(NSFC)under Grant No.11835015,No.12047503 and No.11961141012+1 种基金the NSFC and the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)through the funds provided to the Sino-German Collaborative Research Center TRR110"Symmetries and the Emergence of Structure in QCD"(NSFC Grant No.12070131001,DFG Project-ID 196253076)the CAS Center for Excellence in Particle Physics(CCEPP).
文摘The practice of using the direct ionization radiation (electrons, protons, antiprotons, pions, ions, etc) or of the indirect ionization radiation (photons, neutrons, etc) in economy and social life has led to the introduction of the absorbed dose magnitude (ICRU 1953) defined as the energy absorbed per mass unit of the irradiated substance. This is a fundamental magnitude valid for any type of ionizing radiation, any irradiated material and any radiation energy. In case of clinical hadron beams generated by conventional accelerators or those controlled by lasers, IAEA TRS 398 recommends the absorbed dose to water. This may be determined employing the calorimeter method with water or graphite, chemical method, fluence based measurements as Faraday cups or activation measurements, and the ionization chamber method. In this paper the selected method was the thimble air filled ionization chamber method for determination of absorbed dose to water.
文摘The following article has been retracted due to the investigation of complaints received against it. Mr. Mohammadali Ghorbani (corresponding author and also the last author) cheated the author’s name: Alireza Heidari. The scientific community takes a very strong view on this matter and we treat all unethical behavior such as plagiarism seriously. This paper published in Vol.3 No.2, 208-213, 2012, has been removed from this site.
基金Supported partly by the National Natural Science Foundation of China(12205002)the Natural Science Foundation of Anhui Province,China(2108085MA20,2208085MA10)the key Research Foundation of Education Ministry of Anhui Province of China(KJ2021A0061)。
文摘Two near-threshold peaking structures with spin-parities of J^(PC)=0^(++)were recently discovered by the LHCb Collaboration in the invariant mass distribution of the decay process B^(+)→D_(s)^(+)D_(s)^(-)K^(+).In our study,we employed a coupled-channel model to fit the experimental results published by the LHCb Collaboration,simultaneously fitting the model to the invariant mass distributions of,MD_(s)+D_(s)^(-),M_(D)_(S)^(+)K^(+)and.We utilized a coupled-channel model to search for the poles of and.The determination of the poles is meaningful in itself,and it also lays a foundation for future research on and.Upon turning off the coupled-channel and performing another fit,we observed a change in the fitting quality,and the effect was almost entirely due to the peak of.Therefore,we suggest that may not be a kinematic effect.
基金Supported by NSFC (12293060, 12293061, 12293063, 12175279, 12435002, 12322503, 12175239)the Strategic Priority Research Program of the Chinese Academy of Sciences with (XDB34030301)+1 种基金Guangdong Major Project of Basic and Applied Basic Research (2020B0301030008)the Science and Education Integration Young Faculty Project of University of Chinese Academy of Sciences (YSBR-101)。
文摘We present the first lattice result of the near threshold Λ_(c)Λ_(c)scattering with I(J^(P)) = 0(0^(+)). The calculation is performed on two N_(f)= 2 + 1 Wilson-Clover ensembles with pion mass m_(π)~ 303 MeV and lattice spacing a = 0.07746 fm. Lüscher's finite volume method is utilized to extract the scattering parameters from the finitevolume spectrum. The coupled channel Ξ_(cc)N is ignored in the scattering analysis based on the observation that the energy levels computed from the Λ_(c)Λ_(c)and Ξ_(cc) N operators do not mix. The Σ_(c)Σ_(c) channel is not included either since the energy range explored in this study is well below its threshold. Our results indicate that the interaction in the Λ_(c)Λ_(c)single channel is repulsive, and the scattering length is determined to be a_(0)=-0.21(4)(8) fm, where the first error is statistical and the second is systematic.
基金the National Nature Science Foundations of China(12335002,12375078,11975028)H.Q.Zheng and Z.Xiao are also Supported by"the Fundamental Research Funds for the Central Universities"。
文摘Recently,the LHCb experimental group found an exotic state T_(cc)^(+) from the pp→D^(0)D^(0)π^(+)+X process.A key question is whether it is just a molecule or may have a confined tetraquark ingredient.To investigate this,different methods were used,including a two-channel(D^(∗)+D^(0) and D^(∗)0D^(+))K-matrix unitarization and a single-channel Flatté-like parametrization method analyzed utilizing the pole counting rule and spectral density function sum rule.These analyses demonstrated that T_(cc)^(+) is a molecular state,although the possibility that there may exist an elementary ingredient cannot be excluded,according to an approximate analysis of its production rate.
