Pub Date : 2006-04-01DOI: 10.1556/aph.25.2006.2-4.9
J. Escher, L. Ahle, L. Bernstein, Jason T. Harke
An indirect method for determining cross sections for reactions proceeding through a compound nucleus is presented. Exploring indirect approaches for obtaining reaction cross sections is important since a large number of reactions relevant to astrophysics cannot be measured with currently available techniques. Of particular importance are reactions involving unstable nuclei. Some applications of the Surrogate nuclear reactions method are considered and challenges that need to be addressed are outlined.
{"title":"The Surrogate Method — An Indirect Approach to Compound-Nucleus Reactions","authors":"J. Escher, L. Ahle, L. Bernstein, Jason T. Harke","doi":"10.1556/aph.25.2006.2-4.9","DOIUrl":"https://doi.org/10.1556/aph.25.2006.2-4.9","url":null,"abstract":"An indirect method for determining cross sections for reactions proceeding through a compound nucleus is presented. Exploring indirect approaches for obtaining reaction cross sections is important since a large number of reactions relevant to astrophysics cannot be measured with currently available techniques. Of particular importance are reactions involving unstable nuclei. Some applications of the Surrogate nuclear reactions method are considered and challenges that need to be addressed are outlined.","PeriodicalId":201208,"journal":{"name":"Acta Physica Hungarica A) Heavy Ion Physics","volume":"176 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114078372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-04-01DOI: 10.1556/APH.25.2006.2-4.36
V. Dzhordzhadze
The PHENIX detector at RHIC has been designed to study different signatures of the states of matter created in heavy-ion collisions, and to investigate the spin structure of the nucleon. The PHENIX detector measures muons in two muon spectrometers, located at forward rapidities (1.2 < |η| < 2.4) and hadrons, electrons and photons in the two central spectrometers at midrapidity (|η| <0.35). To make a next step in the PHENIX research program, it is necessary to extend the rapidity coverage beyond the limits set by the existing central spectrometer. The functionality of the PHENIX muon detectors can be extended with added capabilities to measure photonic and hadronic jets. Tungsten calorimeters with silicon pixel readout and fine transverse and longitudinal segmentation are proposed to attain this goal. The proposed calorimeters will be located in the forward directions on either side of the PHENIX interaction point. In this talk we report on the studies of the functionality of the proposed calorimeters: the detector energy resolution, the jet reconstruction capabilities and the characteristics of pion rejection.
{"title":"Extending physics capabilities of the PHENIX detector with calorimetry at forward rapidities","authors":"V. Dzhordzhadze","doi":"10.1556/APH.25.2006.2-4.36","DOIUrl":"https://doi.org/10.1556/APH.25.2006.2-4.36","url":null,"abstract":"The PHENIX detector at RHIC has been designed to study different signatures of the states of matter created in heavy-ion collisions, and to investigate the spin structure of the nucleon. The PHENIX detector measures muons in two muon spectrometers, located at forward rapidities (1.2 < |η| < 2.4) and hadrons, electrons and photons in the two central spectrometers at midrapidity (|η| <0.35). To make a next step in the PHENIX research program, it is necessary to extend the rapidity coverage beyond the limits set by the existing central spectrometer. The functionality of the PHENIX muon detectors can be extended with added capabilities to measure photonic and hadronic jets. Tungsten calorimeters with silicon pixel readout and fine transverse and longitudinal segmentation are proposed to attain this goal. The proposed calorimeters will be located in the forward directions on either side of the PHENIX interaction point. In this talk we report on the studies of the functionality of the proposed calorimeters: the detector energy resolution, the jet reconstruction capabilities and the characteristics of pion rejection.","PeriodicalId":201208,"journal":{"name":"Acta Physica Hungarica A) Heavy Ion Physics","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125181172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-04-01DOI: 10.1556/APH.25.2006.2-4.2
Edward F. Brown, Michelle S. Ouellette
There are over 100 accreting neutron stars in our galaxy, in which matter (typically H/He) is tidally transferred from a secondary companion to the neutron star. Accretion of this matter perturbs the thermal structure of the interior away from that of an isolated cooling neutron star. In this paper. we review how this accretion induces reactions in the crust of the neutron star that keep the interior hot. If the accretion is intermittent, then the heated surface layers are directly observable when accretion stops. This heating also affects the unstable ignition of light elements in the neutron star envelope. Observations of the neutron star cooling following an accretion outburst can in principle constrain the thermal properties of the crust and core.
{"title":"Accreting Neutron Stars as Probes of Dense Matter Physics","authors":"Edward F. Brown, Michelle S. Ouellette","doi":"10.1556/APH.25.2006.2-4.2","DOIUrl":"https://doi.org/10.1556/APH.25.2006.2-4.2","url":null,"abstract":"There are over 100 accreting neutron stars in our galaxy, in which matter (typically H/He) is tidally transferred from a secondary companion to the neutron star. Accretion of this matter perturbs the thermal structure of the interior away from that of an isolated cooling neutron star. In this paper. we review how this accretion induces reactions in the crust of the neutron star that keep the interior hot. If the accretion is intermittent, then the heated surface layers are directly observable when accretion stops. This heating also affects the unstable ignition of light elements in the neutron star envelope. Observations of the neutron star cooling following an accretion outburst can in principle constrain the thermal properties of the crust and core.","PeriodicalId":201208,"journal":{"name":"Acta Physica Hungarica A) Heavy Ion Physics","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125313655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-04-01DOI: 10.1556/APH.25.2006.2-4.25
R. Lacey, P. Chung
The source imaging technique of Brown and Danielewicz has been used to extract two-pion emission source functions over a broad range of kT and centralities in Au+Au collisions at (sqrt s = 200) GeV. The source functions reflect the combined contributions of a short-range Gaussian-like component and a long-range exponential-like component. A parametrization of the source function gives a RMS radius for the long-range source which is approximately three times that for the short-range source. The centrality dependence of the extracted source parameters for the short- and long-range sources indicate similar patterns.
Brown和Danielewicz的源成像技术已被用于在(sqrt s = 200) GeV的Au+Au碰撞中提取宽范围kT和中心的双介子发射源函数。源函数反映了近程类高斯分量和远程类指数分量的综合贡献。源函数的参数化给出了远程源的均方根半径，它大约是短程源的三倍。提取的短源和长源参数的中心性依赖性表明了类似的模式。
{"title":"Evidence for an Emission Source of Large Space-Time Extent in Au+Au Collisions at RHIC","authors":"R. Lacey, P. Chung","doi":"10.1556/APH.25.2006.2-4.25","DOIUrl":"https://doi.org/10.1556/APH.25.2006.2-4.25","url":null,"abstract":"The source imaging technique of Brown and Danielewicz has been used to extract two-pion emission source functions over a broad range of kT and centralities in Au+Au collisions at (sqrt s = 200) GeV. The source functions reflect the combined contributions of a short-range Gaussian-like component and a long-range exponential-like component. A parametrization of the source function gives a RMS radius for the long-range source which is approximately three times that for the short-range source. The centrality dependence of the extracted source parameters for the short- and long-range sources indicate similar patterns.","PeriodicalId":201208,"journal":{"name":"Acta Physica Hungarica A) Heavy Ion Physics","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126142403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-04-01DOI: 10.1556/APH.25.2006.2-4.33
A. Lebedev
J/Ψ’s are produced mostly via interactions involving gluons, and are a sensitive probe of the gluon structure function and its modification in nuclei. They are also considered as a leading signal for studying the creation of hot and dense matter in relativistic heavy ion collision. Measurement of J/Ψ production in different colliding systems is important for understanding the nuclear modification factor, and setting a baseline for the study of J/Ψ suppression in heavy ion collisions. In this talk we report the latest results on J/Ψ measurements by the PHENIX experiment at RHIC in p+p; d+Au, and Au+Au collisions at backward, forward, and mid-rapidity. Nuclear effects are studied as a function of transverse momentum, rapidity and centrality.
{"title":"J/Ψ measurement in p+p, d+Au and Au+Au collisions by the PHENIX experiment at RHIC","authors":"A. Lebedev","doi":"10.1556/APH.25.2006.2-4.33","DOIUrl":"https://doi.org/10.1556/APH.25.2006.2-4.33","url":null,"abstract":"J/Ψ’s are produced mostly via interactions involving gluons, and are a sensitive probe of the gluon structure function and its modification in nuclei. They are also considered as a leading signal for studying the creation of hot and dense matter in relativistic heavy ion collision. Measurement of J/Ψ production in different colliding systems is important for understanding the nuclear modification factor, and setting a baseline for the study of J/Ψ suppression in heavy ion collisions. In this talk we report the latest results on J/Ψ measurements by the PHENIX experiment at RHIC in p+p; d+Au, and Au+Au collisions at backward, forward, and mid-rapidity. Nuclear effects are studied as a function of transverse momentum, rapidity and centrality.","PeriodicalId":201208,"journal":{"name":"Acta Physica Hungarica A) Heavy Ion Physics","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125721266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-04-01DOI: 10.1556/APH.25.2006.2-4.42
J. Lee
Particle production of charged hadrons in Au+Au collisions at (sqrt {s_{NN} } = 200) GeV bas been studied as a function of rapidity by the BRAHMS Collaboration at RHIC. Selected recent results are presented with emphasis on longitudinal dynamics of particle production. The rapidity dependence of particle production imposes more stringent constraints on theoretical models describing dynamics of nuclear matter created by high-energy heavy ion collisions.
{"title":"Probing longitudinal dynamics at RHIC","authors":"J. Lee","doi":"10.1556/APH.25.2006.2-4.42","DOIUrl":"https://doi.org/10.1556/APH.25.2006.2-4.42","url":null,"abstract":"Particle production of charged hadrons in Au+Au collisions at (sqrt {s_{NN} } = 200) GeV bas been studied as a function of rapidity by the BRAHMS Collaboration at RHIC. Selected recent results are presented with emphasis on longitudinal dynamics of particle production. The rapidity dependence of particle production imposes more stringent constraints on theoretical models describing dynamics of nuclear matter created by high-energy heavy ion collisions.","PeriodicalId":201208,"journal":{"name":"Acta Physica Hungarica A) Heavy Ion Physics","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134336799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-04-01DOI: 10.1556/APH.25.2006.2-4.17
C. Höhne
At the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt a dedicated heavy-ion experiment investigating the properties of highly compressed baryonic matter (CBM) is proposed. Its goal will be to explore the QCD phase diagram in the region of moderate temperatures but very high baryon densities. Physics observables of interest, the experimental challenge of measuring them and first feasibility studies on charm production will be discussed.
{"title":"The Compressed Baryonic Matter Experiment at the Future Accelerator Facility FAIR in Darmstadt","authors":"C. Höhne","doi":"10.1556/APH.25.2006.2-4.17","DOIUrl":"https://doi.org/10.1556/APH.25.2006.2-4.17","url":null,"abstract":"At the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt a dedicated heavy-ion experiment investigating the properties of highly compressed baryonic matter (CBM) is proposed. Its goal will be to explore the QCD phase diagram in the region of moderate temperatures but very high baryon densities. Physics observables of interest, the experimental challenge of measuring them and first feasibility studies on charm production will be discussed.","PeriodicalId":201208,"journal":{"name":"Acta Physica Hungarica A) Heavy Ion Physics","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114778650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-04-01DOI: 10.1556/APH.25.2006.2-4.43
M. Abdel-Aziz, S. Gavin
Fluctuation signals of the QCD phase transition in nuclear collisions can be dissipated due to diffusion. Diffusive modes in the standard formulation of relativistic hydrodynamics propagate with infinite speed, violating causality. We develop a causal diffusion equation study the dissipation of net-charge fluctuations. We find that causality restricts the extent to which diffusion can dissipate these fluctuations.
{"title":"Diffusion and two-particle correlations","authors":"M. Abdel-Aziz, S. Gavin","doi":"10.1556/APH.25.2006.2-4.43","DOIUrl":"https://doi.org/10.1556/APH.25.2006.2-4.43","url":null,"abstract":"Fluctuation signals of the QCD phase transition in nuclear collisions can be dissipated due to diffusion. Diffusive modes in the standard formulation of relativistic hydrodynamics propagate with infinite speed, violating causality. We develop a causal diffusion equation study the dissipation of net-charge fluctuations. We find that causality restricts the extent to which diffusion can dissipate these fluctuations.","PeriodicalId":201208,"journal":{"name":"Acta Physica Hungarica A) Heavy Ion Physics","volume":"261 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123691022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The smooth N and Z dependence of nuclear rms charge radii is interpereted by a two-liquid drop model with ϱp+ϱn=ϱ0=const. Proton and neutron radii R p and R n are given in closed form. In addition to rms charge radii, the model yields the nucleon number dependence of the skin thickness, s, e.g. ds=0.00124×dA for Sn isotopes, in agreement with experimental results and theoretical calculations. A strong correlation between the two global parameters of the model — including s stthe skin thickness of the stable isotope — is established. If s stis taken from experiment, the other parameter is also fixed; this parameter (m) characterizes the restoring force responsible for the skin thickness. Its value m=2.2 suggests that — in addition to the number of nucleons in the skin — the skin thickness also influences the distribution of “surplus” nucleons between volume and skin.
{"title":"Description of the smooth rms charge radius surface R(N, Z) and prediction of neutron skin by a two-liquid drop model","authors":"I. Angeli","doi":"10.1556/APH.25.2006.1.4","DOIUrl":"https://doi.org/10.1556/APH.25.2006.1.4","url":null,"abstract":"The smooth N and Z dependence of nuclear rms charge radii is interpereted by a two-liquid drop model with ϱp+ϱn=ϱ0=const. Proton and neutron radii R p and R n are given in closed form. In addition to rms charge radii, the model yields the nucleon number dependence of the skin thickness, s, e.g. ds=0.00124×dA for Sn isotopes, in agreement with experimental results and theoretical calculations. A strong correlation between the two global parameters of the model — including s stthe skin thickness of the stable isotope — is established. If s stis taken from experiment, the other parameter is also fixed; this parameter (m) characterizes the restoring force responsible for the skin thickness. Its value m=2.2 suggests that — in addition to the number of nucleons in the skin — the skin thickness also influences the distribution of “surplus” nucleons between volume and skin.","PeriodicalId":201208,"journal":{"name":"Acta Physica Hungarica A) Heavy Ion Physics","volume":"9 16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130589747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Kaon production in heavy ion collisions — Which observable is best suited to observe in-medium potentials?","authors":"H. Oeschler","doi":"10.1007/BF03177672","DOIUrl":"https://doi.org/10.1007/BF03177672","url":null,"abstract":"","PeriodicalId":201208,"journal":{"name":"Acta Physica Hungarica A) Heavy Ion Physics","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114920213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：