Browsing by Author "Chiou, Chengnan"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item Particle identification by TOF for heavy ion interactions(1990) Chiou, Chengnan; Mutchler, Gordon S.The purpose of the relativistic heavy-ion experiment E810 at the Brookhaven National Laboratory Alternating Gradient Synchrotron(BNL AGS) is to look for indications of a phase transition from hadronic to quark matter: the Quark-Gluon Plasma(QGP). The experiment was performed using a 14.5 $\times$ A Gev/c silicon beam from the BNL AGS to bombard targets of Si, Cu, Sn, Au, and Pb. The experimental apparatus used in the June 1989 run were the BNL Multi-Particle Spectrometer(MPS), the Time Projection Chamber(TPC) system, and the Time-of-Flight(TOF) hodoscope. With a 15m flight path, to separate $\pi\sp-$ from p up to 5-6 Gev/c and $\pi\sp-$ from $k\sp-$ up to 2.5-3 Gev/c, we require that the Root-Mean-Square(RMS) time resolution of the TOF hodoscope be about 150 picoseconds. From the analysis of the TOF beta distribution of fast $\pi\sp-$, a RMS time resolution range of 150-160 ps can be achieved after the time-walk correction.Item Time-of-flight particle identification results from central silicon-silicon and silicon-tungsten collisions at 14.6 x A GeV/c(1992) Chiou, Chengnan; Mutchler, Gordon S.Momentum spectra of $\pi\sp-$, $K\sp-$, p and d have been measured from central collisions of 14.6 $\times$ A GeV/c Si beam on Si and W targets at rapidity 1.9 $<$ y $<$ 2.1. The inverse slope parameters $T\sb0$ obtained by an exponential fit with the transverse mass spectra in transverse kinetic energy are found to be $T\sb0(\pi\sp-) < T\sb0(K\sp-) < T\sb0(p) < T\sb0(d)$. This result is predicted by a radially expanding flow model. From integrated results, the $K\sp-/\pi\sp-$ ratios, (2.7 $\pm$ 0.3) % from Si and (2.4 $\pm$ 0.2) % from W, are consistent with pp collision results. The deuteron production rates can be explained by a relativistic coalescence model.