Recent studies on high-multiplicity events in small collision systems(proton-proton and proton-lead)have drawn considerable research interest toward the possibility of the formation of partonic medium in such systems....Recent studies on high-multiplicity events in small collision systems(proton-proton and proton-lead)have drawn considerable research interest toward the possibility of the formation of partonic medium in such systems.One of the important consequences of the formation of dense partonic medium is the quenching of high-momentum final-state particles,resulting in several experimental observations such as suppression in nuclear modification factor RAA,modification of jet shape observableρ(r)and jet fragmentation(z^(ch))distributions,etc.In this work,we studyρ(r)and z^(ch)for inclusive charged-particle jets in proton-proton(pp)collisions at√s=13 TeV using the PYTHIA 8 Monash 2013 Monte Carlo simulation.We show that the color reconnection(CR)and multiparton interaction(MPI)mechanisms in PYTHIA 8 can lead to an increased rate of jet production.We also find that the mechanisms of MPI and CR and change in the gluonic contribution in high-multiplicity events result in significant modification ofρ(r)and z^(ch)compared to those in minimum bias events for 10<p_(T,jet)^(ch)<20 GeV/c.We notice a direct connection of<N_(MPI)>and gluonic contribution with the amount of modification inρ(r):the larger the number of MPIs and/or gluonic contribution,the larger the amount of modification ofρ(r).展开更多
The potential of muon colliders opens up new possibilities for the exploration of new physics beyond the Standard Model.It is worthwhile to investigate whether muon colliders are suitable for studying gluonic quartic ...The potential of muon colliders opens up new possibilities for the exploration of new physics beyond the Standard Model.It is worthwhile to investigate whether muon colliders are suitable for studying gluonic quartic gauge couplings(gQGCs),which can be contributed by dimension-8 operators in the framework of the Standard Model effective field theory,and are intensively studied recently.In this paper,we study the sensitivity of the processμ^(+)μ^(-)→jjν■to gQGCs.Our results indicate that the muon colliders with c.m.energies larger than 4 TeV can be more sensitive to gQGCs than the Large Hadron Collider.展开更多
The fixed target COMPASS experiment at CERN offers the opportunity to search for exotic mesons and glueball candidates in the light quark sector with unprecedented statistics.Preliminary results from the 2008 data tak...The fixed target COMPASS experiment at CERN offers the opportunity to search for exotic mesons and glueball candidates in the light quark sector with unprecedented statistics.Preliminary results from the 2008 data taken with an incoming negative hadron beam （190 GeV/c,mainly pions） on a liquid hydrogen target are presented.New detectors dedicated to hadron beam measurements have been added.These give access to rare neutral and kaonic channels.An amplitude analysis which will allow to fit simultaneously diffractively and/or centrally produced resonances will be described and compared with those used in the CERN WA102 and BNL E852 experiments.展开更多
It is reported that fermentative liquids with various concentrations of La and Nd affect the fer- mentation of alginic acid from the strain 342 of Azotobacter vinelandii.The results are as follows:When the concentrati...It is reported that fermentative liquids with various concentrations of La and Nd affect the fer- mentation of alginic acid from the strain 342 of Azotobacter vinelandii.The results are as follows:When the concentration of La or Nd was up to 100 ppm,the cell growth is stimulated and the production of alginic acid is promoted.The La or Nd in concentration higher than 200 ppm or 150 ppm inhibits the fermentation, respectively.As the concentration range of La is 0～100 ppm or that of Nd is 0～150 ppm,the yield of fixed nitrogen increases,and the ratio of c_M to c_G(c_M/c_G)decreases with the raise of the concentration of La or Nd.When the concentration range of La is 100～400 ppm and that of Nd is 150～400 ppm,the conclusion is contrary to the above mentioned result.展开更多
驱动美国托马斯杰斐逊国家加速器装置(Thomas Jefferson National Accelerator Facility,简称JLab)的能量升级到12GeV的科学是研究胶子激发和色禁闭的起因,研究原子核的构件核子是如何由夸克和胶子构成的,研究原子核的结构及寻找新物理...驱动美国托马斯杰斐逊国家加速器装置(Thomas Jefferson National Accelerator Facility,简称JLab)的能量升级到12GeV的科学是研究胶子激发和色禁闭的起因,研究原子核的构件核子是如何由夸克和胶子构成的,研究原子核的结构及寻找新物理等的一门科学.实验设备是12GeV的加速器、各种超导磁谱仪及极化靶等.在能量为12GeV的加速器中,将采用深度遍举过程和极化实验.展开更多
基金the Inspire Fellowship research grant(DST/INSPIRE Fellowship/2018/IF180285).
文摘Recent studies on high-multiplicity events in small collision systems(proton-proton and proton-lead)have drawn considerable research interest toward the possibility of the formation of partonic medium in such systems.One of the important consequences of the formation of dense partonic medium is the quenching of high-momentum final-state particles,resulting in several experimental observations such as suppression in nuclear modification factor RAA,modification of jet shape observableρ(r)and jet fragmentation(z^(ch))distributions,etc.In this work,we studyρ(r)and z^(ch)for inclusive charged-particle jets in proton-proton(pp)collisions at√s=13 TeV using the PYTHIA 8 Monash 2013 Monte Carlo simulation.We show that the color reconnection(CR)and multiparton interaction(MPI)mechanisms in PYTHIA 8 can lead to an increased rate of jet production.We also find that the mechanisms of MPI and CR and change in the gluonic contribution in high-multiplicity events result in significant modification ofρ(r)and z^(ch)compared to those in minimum bias events for 10<p_(T,jet)^(ch)<20 GeV/c.We notice a direct connection of<N_(MPI)>and gluonic contribution with the amount of modification inρ(r):the larger the number of MPIs and/or gluonic contribution,the larger the amount of modification ofρ(r).
基金supported in part by the National Natural Science Foundation of China under Grants Nos.11905093 and 12147214the Natural Science Foundation of the Liaoning Scientific Committee No.LJKZ0978.
文摘The potential of muon colliders opens up new possibilities for the exploration of new physics beyond the Standard Model.It is worthwhile to investigate whether muon colliders are suitable for studying gluonic quartic gauge couplings(gQGCs),which can be contributed by dimension-8 operators in the framework of the Standard Model effective field theory,and are intensively studied recently.In this paper,we study the sensitivity of the processμ^(+)μ^(-)→jjν■to gQGCs.Our results indicate that the muon colliders with c.m.energies larger than 4 TeV can be more sensitive to gQGCs than the Large Hadron Collider.
基金Supported by German Bundesministerium für Bildung und Forschung
文摘The fixed target COMPASS experiment at CERN offers the opportunity to search for exotic mesons and glueball candidates in the light quark sector with unprecedented statistics.Preliminary results from the 2008 data taken with an incoming negative hadron beam （190 GeV/c,mainly pions） on a liquid hydrogen target are presented.New detectors dedicated to hadron beam measurements have been added.These give access to rare neutral and kaonic channels.An amplitude analysis which will allow to fit simultaneously diffractively and/or centrally produced resonances will be described and compared with those used in the CERN WA102 and BNL E852 experiments.
文摘It is reported that fermentative liquids with various concentrations of La and Nd affect the fer- mentation of alginic acid from the strain 342 of Azotobacter vinelandii.The results are as follows:When the concentration of La or Nd was up to 100 ppm,the cell growth is stimulated and the production of alginic acid is promoted.The La or Nd in concentration higher than 200 ppm or 150 ppm inhibits the fermentation, respectively.As the concentration range of La is 0～100 ppm or that of Nd is 0～150 ppm,the yield of fixed nitrogen increases,and the ratio of c_M to c_G(c_M/c_G)decreases with the raise of the concentration of La or Nd.When the concentration range of La is 100～400 ppm and that of Nd is 150～400 ppm,the conclusion is contrary to the above mentioned result.
文摘驱动美国托马斯杰斐逊国家加速器装置(Thomas Jefferson National Accelerator Facility,简称JLab)的能量升级到12GeV的科学是研究胶子激发和色禁闭的起因,研究原子核的构件核子是如何由夸克和胶子构成的,研究原子核的结构及寻找新物理等的一门科学.实验设备是12GeV的加速器、各种超导磁谱仪及极化靶等.在能量为12GeV的加速器中,将采用深度遍举过程和极化实验.
