Pion Interferometry for Hydrodynamical Expanding Source with a Finite Baryon Density

We calculate the two-pion correlation function for an expanding hadron source with a finite baryon density. The space-time evolution of the source is described by relativistic hydrodynamics and the Hanbury-Brown-Twiss (HBT) radius is extracted after effects of collective expansion and multiple scattering on the HBT interferometry have been taken into account, using quantum probability amplitudes in a path-integral formalism. We find that this radius is substantially smaller than the HBT radius extracted from the freeze-out configuration.Comment: 4 pages, 2 figure

Interferometry signatures for QCD first-order phase transition in heavy ion collisions at GSI-FAIR energies

Using the technique of quantum transport of the interfering pair we examine the Hanbury-Brown-Twiss (HBT) interferometry signatures for the particle-emitting sources of pions and kaons produced in the heavy ion collisions at GSI-FAIR energies. The evolution of the sources is described by relativistic hydrodynamics with the system equation of state of the first-order phase transition from quark-gluon plasma (QGP) to hadronic matter. We use quantum probability amplitudes in a path-integral formalism to calculate the two-particle correlation functions, where the effects of particle decay and multiple scattering are taken into consideration. We find that the HBT radii of kaons are smaller than those of pions for the same initial conditions. Both the HBT radii of pions and kaons increase with the system initial energy density. The HBT lifetimes of the pion and kaon sources are sensitive to the initial energy density. They are significantly prolonged when the initial energy density is tuned to the phase boundary between the QGP and mixed phase. This prolongations of the HBT lifetimes of pions and kaons may likely be observed in the heavy ion collisions with an incident energy in the GSI-FAIR energy range.Comment: 16 pages, 4 figure

Analysis of pion elliptic flows and HBT interferometry in a granular quark-gluon plasma droplet model

In many simulations of high-energy heavy-ion collisions on an event-by-event analysis, it is known that the initial energy density distribution in the transverse plane is highly fluctuating. Subsequent longitudinal expansion will lead to many longitudinal tubes of quark-gluon plasma which have tendencies to break up into many spherical droplets because of sausage instabilities. We are therefore motivated to use a model of quark-gluon plasma granular droplets that evolve hydrodynamically to investigate pion elliptic flows and Hanbury-Brown-Twiss interferometry. We find that the data of pion transverse momentum spectra, elliptic flows, and HBT radii in \sqrt{s_{NN}}=200 GeV Au + Au collisions at RHIC can be described well by an expanding source of granular droplets with an anisotropic velocity distribution.Comment: 9 pages, 6 figures, in Late

Signals in Single-Event Pion Interferometry for Granular Sources of Quark-Gluon Plasma Droplets

We investigate two-pion Bose-Einstein correlations of quark-gluon plasma droplet sources in single-event measurements. We find that the distribution of the fluctuation between correlation functions of the single- and mixed-events provide useful signals to detect the granular structure of the source.Comment: 6 pages, 6 figures, in LaTe

Inner surface enhanced femtosecond second harmonic generation in thin ZnO crystal tubes

At room temperature, efficient second harmonic generation (SHG) emission is observed in thin ZnO crystal hollow rods (tubes) with diameter∼0.2 mm under the excitation of femtosecond laser from 700 to 860 nm. Power and polarization dependence of the SHG signal on the primary excitation beam is also measured. The multiple total reflections between the outer and inner surfaces of the sample are analyzed to be responsible for the efficient SHG. Ninefold amplification of SHG signal in the tube structure is estimated. © 2011 American Institute of Physics.published_or_final_versio

Ancient genome analyses shed light on kinship organization and mating practice of Late Neolithic society in China

Anthropology began in the late nineteenth century with an emphasis on kinship as a key factor in human evolution. From the 1960s, archaeologists attempted increasingly sophisticated ways of reconstructing prehistoric kinship but ancient DNA analysis has transformed the field, making it possible, to directly examine kin relations from human skeletal remains. Here, we retrieved genomic data from four Late Neolithic individuals in central China associated with the Late Neolithic Longshan culture. We provide direct evidence of consanguineous mating in ancient China, revealing inbreeding among the Longshan populations. By combining ancient genomic data with anthropological and archaeological evidence, we further show that Longshan society household was built based on the extended beyond the nuclear family, coinciding with intensified social complexity during the Longshan period, perhaps showing the transformation of large communities through a new role of genetic kinship-based extended family units.Introduction Results - Archaeological and anthropological insight into the Pingliangtai site - Ancient DNA authentication and uniparental genetic analyses - Neolithic period genetic contribution into the Yellow River basin from southern China - Three Pingliangtai individuals share second-degree relatedness (SDR) to each other - Parental relatedness in the Pingliangtai individuals Discussio

Luminescence signature of free exciton dissociation and liberated electron transfer across the junction of graphene/GaN hybrid structure

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TO ACHIEVE REAL IMMERSION: THE 3D VIRTUAL AND PHYSICAL RECONSTRUCTION OF CAVE 3 AND CAVE 12 OF YUNGANG GROTTOES

As the 3D laser scanning and photogrammetry technologies continue to mature, more and more applications founded in numerous areas. The realistic 3D models are mainly adopted for digital display uses, such as the 3D game, web showcases, head-mounted display, etc. While we are enjoying the vivid digital sceneries through different kinds of digital display screens, there are still challenges exist for the 3D printing application, especially for large size objects. In this article, we will present an approach on digitizing and 3D replicating large grottoes. Unlike 3D rendering, 3D printing requires high detailed shape data for the fabrication. Such demands cause many technical difficulties including huge data amount, accurate dense point cloud, high-resolution texture mapping. We chose cascade SfM, grouped MVS, automatic texture mapping to prepare the high definition colored 3D model for printing and painting references. Meanwhile, we optimized 3D printing procedure as well as post-processing, installation, lacquer and painting. Two replicas of 10- meter sized grottoes have been manufactured after four years of efforts, which have earned some appreciations from audiences

Chlamydia-related knowledge, opinion to opportunistic testing, and practices of providers among different sexually transmitted infections related departments in hospitals in Shenzhen city, China

Background: Chlamydia trachomatis (CT) infection could lead to seriously adverse outcomes if left untreated. This study aimed to determine CT-related knowledge, opinion to testing, and practices of providers among different sexually transmitted infections (STI) related departments in hospitals in Shenzhen city, China, and also to explore the differences in these responses. Materials and methods: From 1st April 2018 to 15th April 2018, a cross-sectional study was conducted in Shenzhen and 64 of 66 hospitals agreed to participate in this study. In the hospital sites, all the providers from the department of obstetrics and gynecology, department of dermatology and venereology, department of urology, and anorectal surgical department were recruited. A structured paper-based questionnaire was used to obtain data on CT-related information. Results: A total of 355 providers from 64 hospitals participated in the current study. Compared to providers from the department of dermatology and venereology, those from the department of obstetrics and gynecology (OR = 0.31, 95% CI 0.16—0.62), department of urology (OR = 0.32, 95% CI 0.16—0.65), and anorectal surgical department (OR = 0.25, 95% CI 0.09—0.71) were less likely to identify that “Be in a long-term mutually monogamous relationship with a partner who has been tested and has negative STI test results.” is an appropriate way for a sexually active person to reduce risk of getting CT. Also, those from the department of obstetrics and gynecology (OR = 0.45, 95% CI 0.23—0.87) were less likely to identify that “Use latex condoms the right way every time you have sex” is another appropriate way. A high proportion of providers agreed that all sexually active patients attending to their department should be screened regularly (77.1%), and they are willing to offer opportunistic CT screening (96.0%). Only 11.4% of respondents correctly identified that the appropriate time frame of the CT retesting is three months. Conclusions: Providers among STI-related departments in hospitals showed a very high willingness to offer opportunistic CT screening. However, this study showed important gaps in providers’ knowledge and practices in China, targeted training in CT-related knowledge and practice is urgently needed