# Presentation: 192707

## FTPC and its Utility to PMD program 

- _OUTLINE_
- FTPC and PMD: A comparison
- FTPC and PMD: Physics issues
- Summary

- FTPC Review: BNL, July 19, 2004

- July 19, 2004

## FTPC and PMD: A Comparison

| Item | FTPC-E | PMD |
| --- | --- | --- |
| 1. -coverage | -2.5 to -4.0 | -2.3 to -3.8 |
| 2. Coverage | Full  | Full |
| 3. Charged particles | Yes | No |
| 4. Photons  | No | Yes |
| 5. Electrons  | Yes | Yes |
| 6. Charged Momentum | Yes 
(pT>100(?) MeV) | ---- |
| 7. Photon Momentum | ---- | No |

- July 19, 2004

## Of Hadrons,  Photons & Electrons

-  In the preshower plane of PMD
-   hadrons hit one cell (ncell=1)
-   electrons and photons shower in the lead plane
-      and their clusters have ncell>1
-  FTPC tracks projected to the preshower plane of PMD
-    are matched to clusters on the preshower plane.
-  If the matched clusters are with ncell=1 these
-   are hadrons otherwise those would be electrons.
- This provides good electron identification.

_**Of Hadrons,  Photons & Electrons**_

- July 19, 2004

## FTPC and PMD: Physics Issues

- Using FTPC tracks for PMD MeV-ADC Calibration
- FTPC tracks and PMD clusters for Electron-identification
- Multiplicity Fluctuations: Charged *vs.* neutral
- Disoriented Chiral Condensates (DCC)
- Global Fluctuations in charged and neutral
- Local Fluctuations in charged and neutral
- With fluctuation observables
- With Wavelets
- Azimuthal asymmetry and flow

- July 19, 2004

## PMD: MeV-ADC Calibration 

_**using FTPC tracks**_

_***IDEA:***_
-  Hadron and electron tracks can be determined from the
-    cluster-size of the cells in preshower plane.
-  Track momenta and energy of FTPC tracks are known.
-  The cluster ADC in the preshower plane for the matched
-     tracks are determined.
-  By selecting tracks of different momenta one can obtain
-    a Energy(MeV) to ADC curve.

- July 19, 2004

## 62.4 GeV Data (Au+Au)

- _62.4 GeV Data (Au+Au)_

- FTPC tracks 0-10 GeV window
- hadrons, ncell=1 in PMD

- Raghunath Sahoo

- FTPC tracks 0-10 GeV window
- electrons, ncell>1 in PMD.
- - Low statistics

- July 19, 2004

## Event Display

_**Event Display**_

**FTPC**

**PMD**

- July 19, 2004

## FTPC spectra

_**FTPC spectra**_

- ---- Maria J. Mora Corral 2002

- July 19, 2004

## Disoriented Chiral Condensates

**In normal case:   **
**            **Each of the pion flavors are roughly equally populated.

- Large fluctuations in number of
- photons and charged particles

_**Disoriented Chiral Condensates**_

- July 19, 2004

## FLUCTUATIONS by using WAVELETS

**  **Analysis according to scale:
-                Number of bins = 2*j* where *j *is the scale

- Input function: no. of
- Particles in a bin
- Output: Father function
- Coefficients (FFC)
- at each *j.*

- Provide a new mindset in
- Data Analysis.

- July 19, 2004

## Formation of DCC – upper limits

- 1. Phys.Lett.B420:169-179,1998
- 2. Phys.Rev.C64:011901,2001
- 3. nucl-ex/0206017, to be published in PRC
- Krzywicki & Serreau Phys. Lett.B 448  (1999) 257

_**Formation of DCC – upper limits**_

- 0-5% central

**Global DCC**

- July 19, 2004

## DCC: METHOD OF ANALYSIS

- DCC MODEL :  Introduce DCC-type fluctuations in VENUS event generator by isospin flipping of pions with the probability
-  Domain defined in terms of its extent in pseudo-rapidity and azimuthal angle

- of normal distribution

- July 19, 2004

## DCC POSSIBILITIES 

- Using Momentum information of particles

-  To look for DCC in relativistic heavy-ion collisions_       _
-      1.  Have a photon multiplicity detector along with a  charged particle multiplicity detector which  gives particle wise momentum information
-       2.   Analyze photon excess  events

- B. Mohanthy, T.K. Nayak, D.P. Mahapatra and Y.P. Viyogi
- Int.J.Mod.Phys.A19:1453-1474,2004

**Strength**

- July 19, 2004

## A Fluctuation probe for DCC

_**A Fluctuation probe for DCC**_

- B. Mohanty, T. Nayak, D.P. Mahapatra
- Phys.Rev.C66:044901,2002

- July 19, 2004

## DCC search

- For both set of events measure and compare the following proposed signals:
- Kaon correlations (KsK+ vs K+K-)         Gavin, Kapusta
- Two-particle (HBT) correlations           Gavin
- Dilepton signals                                      Koch, Randrup, X-N Wang
- mega and anti-Omega abundances     Kapusta, SMH Wong
- Direct photons                                        Charng et al. (Phys.Lett. B548 (2002) 175
- Pion Lasers                                             Sinyukov   Pratt
- DCC and Flow                                       Mishra, Nandi, TN, Mohanty, Mahapatra

- Using charged particle and photon multiplicities:
- classify events based on wavelet or correlation analysis as:
- Normal events which are within 2 or 3 sigma from the mean
- Not-so-Normal events beyond that.

- July 19, 2004

## Azimuhal Asymmetry and Flow

-   Correlation of event plane obtained from PMD with
-    those of FTPC from East and FTPC from West side. This
-    should be interesting given v2’s dependence on rapidity.

- July 19, 2004

## Summary

- FTPC is important for the physics program of STAR and
- what we like to do for PMD.

- July 19, 2004