Jie Zhang

Bio: Jie Zhang is an academic researcher from East China University of Science and Technology. The author has contributed to research in topics: Medicine & Large Hadron Collider. The author has an hindex of 178, co-authored 4857 publications receiving 221720 citations. Previous affiliations of Jie Zhang include University of Bedfordshire & CERN.

Precise Mapping of the Magnetic Field in the CMS Barrel Yoke using Cosmic Rays

Abstract: The CMS detector is designed around a large 4 T superconducting solenoid, enclosed in a 12000-tonne steel return yoke. A detailed map of the magnetic field is required for the accurate simulation and reconstruction of physics events in the CMS detector, not only in the inner tracking region inside the solenoid but also in the large and complex structure of the steel yoke, which is instrumented with muon chambers. Using a large sample of cosmic muon events collected by CMS in 2008, the field in the steel of the barrel yoke has been determined with a precision of 3 to 8% depending on the location.

Measurement of the production cross section of prompt J/ψ mesons in association with a W± boson in pp collisions at √s = 7 TeV with the ATLAS detector

Abstract: Measurement of the production cross section of prompt j/psi mesons in association with a W (+/-) boson in pp collisions root s=7 TeV with the ATLAS detector

Elliptic Flow of Charm and Strange Hadrons in High-Multiplicity p+Pb Collisions at √sNN=8.16 TeV

Abstract: The elliptic azimuthal anisotropy coefficient (v2) is measured for charm (D^0) and strange (K^0_S, Λ, Ξ−, and Ω−) hadrons, using a data sample of p + Pb collisions collected by the CMS experiment, at a nucleon-nucleon center-of-mass energy of √s_(NN)= 8.16 TeV. A significant positive v2 signal from long-range azimuthal correlations is observed for all particle species in high-multiplicity p + Pb collisions. The measurement represents the first observation of possible long-range collectivity for open heavy flavor hadrons in small systems. The results suggest that charm quarks have a smaller v_2 than the lighter quarks, probably reflecting a weaker collective behavior. This effect is not seen in the larger PbPb collision system at √s_(NN)= 5.02 TeV, also presented.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

A new mathematical model for relative quantification in real-time RT-PCR.

Abstract: Use of the real-time polymerase chain reaction (PCR) to amplify cDNA products reverse transcribed from mRNA is on the way to becoming a routine tool in molecular biology to study low abundance gene expression. Real-time PCR is easy to perform, provides the necessary accuracy and produces reliable as well as rapid quantification results. But accurate quantification of nucleic acids requires a reproducible methodology and an adequate mathematical model for data analysis. This study enters into the particular topics of the relative quantification in real-time RT–PCR of a target gene transcript in comparison to a reference gene transcript. Therefore, a new mathematical model is presented. The relative expression ratio is calculated only from the real-time PCR efficiencies and the crossing point deviation of an unknown sample versus a control. This model needs no calibration curve. Control levels were included in the model to standardise each reaction run with respect to RNA integrity, sample loading and inter-PCR variations. High accuracy and reproducibility (<2.5% variation) were reached in LightCycler PCR using the established mathematical model.