# Presentation: 182773

## H  4l for Physics ValidationStatus and Plan

**K****étévi A. Assamagan & Alexandre Khodinov**
**BNL, November 24, 2003**

## H4l for Physics Validation

**Introduction**
**H********2e2******
**Current Status**
**conclusion**

## Introduction

**H********4******** : E. Meoni & F. Cerutti, CERN (MOORE+MuID)**
**H********4******** : J-F Laporte et. Al, SACLAY (Muonbox+STACO)**
**H ********4e  : M. Riveline & E. Gross, Weizmann Institute, (ECAL+IpatRec)**

**Current H********4l studies (for validation) since the physics TDR **

**Very new : H********2e2******** : K. Assamagan & K. Khodinov**

## Introduction

**gb ******** tH****+**** ******** ttb ******** jj(****l****n)b ****l****n(jj)b b : complicated final state. Need to understand simpler objects first. **
**H********4****l**** good choice, to understand muon and electron reconstruction before adding jets**

## H 2e2

**H********4l generated and simulated by A. Khodinov : 100 k total. The sample contains H********4l, H********4******** and H********2e2******
**We need and will generate more events**
**H********4e and H********4******** data to reproduce the results of other groups**
**Our main interest : H********2e2******

## H2e2

**Muon Spectrometer**
**MOORE : track parameters at the spectrometer**
**MuID : track extrapolated to the vertex**
**Muonbox : track extrapolated to the vertex**
**Inner Detector**
**IPatRec**
**Xkalman**
**Track Matching**
**MuID Combined : Statistical Combination of MuID and IPatRec tracks**
**STACO :  Statistical Combination of Muonbox and Xkalman tracks**

**Available tools for ******** reconstruction**

**STACO : Fortran version used by SACLAY. ATHENA version **
**Expected by February **

## H2e2

**MOORE, MuID, MuID Combined**
** ****Current Active Developers :**
**   ****D. Adams, K. Assamagan, M. Bigletti, G. Cataldi, A. Farilla, S. Goldfarb, K. Mair, A. Nairz, A. Poppleton, M. Primavera, S. Rosati, J. Shank, S. Spagnolo, G. Stavropoulos**
**MOORE phone meetings ~1 / month : status of MOORE & physics validation results are discussed. Problems and discrepancies in this analysis will be reported and discussed in the MOORE group**

## H2e2

**Muonbox and STACO**
**Active Developers**
**   ****The SACLAY Group, led by J-F Laporte & M Virchaux**
**J-F Laporte promised an ATHENA version of STACO by February**

## Current Analysis Status

**We have concentrated on the reconstruction of H********4********:**
**To reproduce the results of E. Meoni & F. Cerutti (MOORE) and of SACLAY (Muonbox). ****See the talk by A. Khodinov**
**Next, we will look at H********4e**
**To reproduce the results of the TDR or of M. Riveline & E. Gross**
**Then, we will study H********2e2********, our main interest!**
**Finally, we will study the backgrounds to H********2e2******** **

## Current Analysis Status

**Our H********4******** invariant mass resolution :             ******** ******** 2 GeV, MuID Combined. ****See the talk by Alex Khodinov for details**
**E. Meoni & F. Cerutti (MuID Combined)         ******** ******** 1.60 GeV**
**SACLAY (Muonbox+STACO) ******** ******** 1.54 GeV**
**We do not have STACO. We cannot compare our result to SACLAY’s. But we should get results consistent with that of E. Meoni & F. Cerutti. We will initiate discussions to understand and resolve the discrepancy.**

## Conclusions

**We are studying H********2e2******** for physics validation**
**We have 100k  H********4l events**
**H********4******** mass resolution ~ 2. GeV compared to 1.6 and 1.54 GeV from CERN and SACLAY (we trying to understand the discrepancy)**
**Then, we will look at H********4e**
**Finally, we will study H********2e2********, our main interest**
**We have to generate more events with filter: keep events with 4leptons with p****T**** and ******** cuts**