\begin{slide}{} {\Large VI. \underline{Data Analysis}}\\ \begin{center} \underline{Charged-Particle Overview} \end{center} \begin{enumerate} \item Inclusive Charged-Particle Spectra \begin{itemize} \item Preliminary Analyses Only \item Reasonable Shapes of \begin{displaymath} {{dN}\over{d\eta}} \; \; \& \; \;{{dN}\over{d\phi}} \end{displaymath} \item Normalization Consistent with\\ Extrapolations from UA5 and CDF \item Overall Normalization Needs More Work \end{itemize} \item \underline{Bottom Line}: \begin{itemize} \item No Surprises, So Far,\\ at this Level of the Analysis \item Many Corrections to Apply \end{itemize} \end{enumerate} \vfill\eject \begin{center} {\Large \underline{DCC Search: Analysis Challenges}} \end{center} \begin{itemize} \item Small Acceptance:\\ Improbable that both $\gamma$'s from a $\pi^{0}$ Seen \item Conversion Efficiency per $\gamma \approx 50 \%$ \item Not All $\gamma$'s come from $\pi^{0}$'s \item Not All Observed Charged Tracks\\ Come from $\pi^{\pm}$ \item Detection Efficiencies for Charged Tracks and $\gamma$'s:\\ Momentum Dependent and Unequal \item Detection Efficiency Correlations\\ $\sim$ Observed Multiplicity,\\ Background Density, etc. \end{itemize} \vfill\eject \begin{center} {\Large \underline{Input to Efficiency Determination}} \end{center} \begin{itemize} \item Varying Thickness of Pb Converter\\ ($0, 0.5 X_{0},1.0 X_{0},2.0 X_{0}$) \item Varying Composition of Pb Converter\\ ($1.0 X_{0}, 1.0 Fe$) \item Varying Window Thickness \item Different Chamber Configurations:\\ (Original vs. Closely Packed) \item Widely Varying Running Conditions \item PYTHIA/GEANT Simulations \end{itemize} \vfill\eject \begin{center} \underline{DCC Search Strategy-1} \end{center} \begin{itemize} \item Generating Functions \item Factorial and Cumulant Moments \end{itemize} \begin{itemize} \item $P_{N} \equiv$ Probability of N $\pi$'s Being Produced \item Binomial Distribution\\ of Charged \& Neutral Pions;\\ with Neutral Fraction f: \begin{displaymath} P(N_{ch}, N_{0})= f^{N_{0}}(1-f)^{N_{ch}}{{N!} \over {N_{0}!N_{ch}!}}P_{N} \end{displaymath} \begin{displaymath} N = N_{ch} + N_{0} \end{displaymath} \end{itemize} \vfill\eject \begin{center} \underline{DCC Search Strategy-2} \end{center} Assume the Parent Pion Distribution\\ $\sim$ Superposition of Poisson Distributions: \begin{displaymath} P_{N} = \int_{0}^{\infty}d\mu \, \rho(\mu){{\mu^{N}e^{-\mu}}\over {N!}} \end{displaymath} Construct Generating Function: \begin{eqnarray*} G(z_{ch}, z_{0}) & = & \sum\limits_{N_{ch},N_{0}=0}^{\infty}z_{ch}^{N_{ch}}z_{0}^{N_{0}}P(N_{ch},N_{0}) \\ & = & \int_{0}^{\infty}d\mu \, \rho(\mu)\int_{0}^{1}df \, p(f)e^{\mu(z-1)} \end{eqnarray*} where \begin{displaymath} z = fz_{0} + (1 - f)z_{ch} \end{displaymath} \begin{itemize} \item Assume For Generic Pion Production: \begin{displaymath} p(f) = \delta(f - {{1}\over{3}}) \end{displaymath} \item Assume For DCC Production: \begin{displaymath} p(f) = {{1}\over{2\sqrt{f}}} \end{displaymath} \end{itemize} \vfill\eject \begin{center} {\Large \underline{DCC Search Strategy-3}} \end{center} Note: \begin{itemize} \item For Generic Production, $G(z_{ch}, z_{0})$ is a function of only one variable \item For DCC it is \underline{NOT} \end{itemize} \vfill\eject \begin{center} {\Large \underline{DCC Search Strategy-4}} \end{center} Define \begin{itemize} \item $\epsilon_{ch}=$ Probability of Observing Charged-Pion Track \item $\epsilon_{m}=$ Probability of Seeing m $\gamma$'s from the decaying $\pi^{0}$ \end{itemize} \begin{displaymath} \epsilon_{0}+ \epsilon_{1}+ \epsilon_{2} =1 \end{displaymath} Assume $\epsilon_{m}$'s are Uncorrelated with Other Parameters\\ Then Generating Function for\\ \underline{Observed} Distribution $G(z_{ch},z_{\gamma})$\\ Obtained by Substitution: \begin{eqnarray*} z_{0} & \rightarrow & \epsilon_{0}+ \epsilon_{1}z_{\gamma}+ \epsilon_{2}z_{\gamma}^{2}\\ z_{ch} & \rightarrow & (1-\epsilon_{ch})+ \epsilon_{ch}z_{ch} \end{eqnarray*} \vfill\eject \begin{center} {\Large \underline{DCC Search Strategy-5}} \end{center} Note: \begin{itemize} \item For Generic Production ($f = 1/3$) the Phenomenological G is still a Function of One Variable \item DCC Correlations can Survive into Correlations Between Measured Quantities \item Useful Quantitites for Phenomenology are \underline{Factorial Moments}: \begin{displaymath} f_{mn} = (m, n)^{th} \; Derivative \, of \, G(z_{ch},z_{\gamma}) \end{displaymath} at $z_{ch}=z_{\gamma}=1$ \vfill\eject \begin{center} {\Large \underline{DCC Search Strategy-6}} \end{center} \item \underline{Examples}: \begin{eqnarray*} f_{10} & = & \\ f_{01} & = & \\ f_{11} & = & \\ f_{20} & = & \\ f_{30} & = & ,\\ f_{21} & = & \end{eqnarray*} \item These Moments are Easily Extracted from Data \item Sensitivity to Statistics \& \\ Tail of Distributions Can be Tested Straightforwardly \end{itemize} \vfill\eject \begin{center} {\Large \underline{DCC Search Strategy-7}} \end{center} \begin{itemize} \item Within our Assumptions:\\ Ratios of (Normalized)\\ Factorial Moments are: \begin{itemize} \item Independent of Efficiency Corrections \item Unity if No DCC is Present \item Very Different for Pure DCC \end{itemize} \vfill\eject \begin{center} {\Large \underline{DCC Search Strategy-8}} \end{center} \item Examples: \begin{eqnarray*} r_{2} & = & {{f_{11}f_{10}}\over{f_{20}f_{01}}}= 1(Generic)\\ & \,&\; \; \; \; \; \; \; \; \; \;\; \; \; ={{1}\over{2}}(DCC)\\ r_{3} & = & {{f_{21}f_{10}}\over{f_{30}f_{01}}} = 1(Generic)\\ & \, & \; \; \; \; \; \; \; \; \; \;\; \; \; ={{1}\over{3}}(DCC) \end{eqnarray*} \item Generalization:\\ If $\epsilon_{2} =0$ ($2\gamma$ Efficiency Vanishes),\\ No Correlations,\\ \& No DCC, then \begin{displaymath} r_{jk}= {{f_{jk}}\over{f_{(j+k)0}}}({{f_{10}}\over{f_{01}}})^{k}=1 \end{displaymath} \end{itemize} \vfill\eject \begin{center} {\Large \underline{Very Preliminary Results-1}} \end{center} \begin{itemize} \item \underline{Results for $r_{2}\equiv r_{11}$}\\ (Based on 1995 Runs ($10^{6}$ Events) \begin{eqnarray*} r_{2} & = & 0.91 \pm .01 (DATA)\\ r_{2} & = & 0.96 \pm .05 (Generic)\\ r_{2} & = & 0.56 \pm .02 (Pure DCC + GEANT) \end{eqnarray*} Note: Generic $\sim$ PYTHIA/GEANT\\ Also Checked: \begin{itemize} \item No Significant Run-to-Run Dependence \item No Significant Dependence on Converter\\ Thickness or Composition \end{itemize} \vfill\eject \begin{center} {\Large \underline{Very Preliminary Results-2}} \end{center} \item \underline{Results for $r_{2} ($1996 Data)} \begin{displaymath} r_{2} = 0.98 \pm .01 \end{displaymath} (Normal Trigger;$\sim 10^{6}$ Events) \begin{displaymath} r_{2} = 1.08 \pm .06 \end{displaymath} ($x_{F}=0.9$, Upstream Tag; 10\,k Events) \begin{itemize} \item Some Changes in Tracking Algorithms \item Chamber Configuration Changed; Lower Backgrounds \end{itemize} \vfill\eject \begin{center} \underline{Very Preliminary Results-3} \end{center} \item \underline{Very Preliminary Results for $r_{ij}$ (1996 Data)} \begin{eqnarray*} r_{11} & = & 0.98 \pm .01 \; \; r_{02}=1.50 \pm .01 \\ r_{21} & = & 0.99 \pm .01 \; \; r_{12}=1.41 \pm .03 \\ r_{31} &= & 1.02 \pm .04 \; \; r_{22}=1.40 \pm .07 \\ r_{03} & = & 2.97 \pm .10 \; \; r_{13}=2.64 \pm .18 \end{eqnarray*} \vfill\eject \begin{center} {\Large \underline{Results So Far: Summary}} \end{center} \begin{itemize} \item Data is Consistent with\\ Only Generic Production Mechanisms \item Dependence of $r_{ij}$ on Systematic Effects $\leq$ 5\% \item Sensitivity to DCC Admixture is at $10-20\%$ Level\\ (Depends on Modeling, etc.) \end{itemize} \end{itemize} \begin{center} {\Large Many More Studies Need to Be Done} \end{center} \end{slide}{}