1. Non-Pointing Photon Work at UC Santa Cruz / SCIPP ATLAS RPV/Long-lived Physics Group November 19 2008 Bruce Schumm, UCSC/SCIPP

2. Initial goal: include conversions in reconstruction Mauro Donega, UPenn Conversion radius resolution may be good enough to provide an independent constraint on GMSB parameters Pointing accuracy of reconstructed conversion may be quite good Reconstructed radius of material-induced conversions

3. However: conversions only available in release 14, so must migrate analysis to new release (using 14.2.20; not ideal, but workable for conversions)  Intermediate goal: develop release 14 DPD for non-pointing photon analysis First step: migrate non-standard photon identification to release 14 via isEMMasks (applied in EVPhotonInserter)

4. Default vs. Non-Pointing Gamma Selection (?) Mask Bit Default CriterionNP  selection 0  rangeYES 1Hadronic leakageYES 4Middle energyYES 5Middle ratio 37NO 6Middle ratio 33NO 7Middle widthNO 8Strips energy ratioYES 9E 2,max NO 10  E 2,max NO 111 st sample widthNO 121 st sample shapeNO 13Weighted width NO 14IsolationYES  Non- pointing photon mask is 0x4113

5. Raw photon container Default selection Non-pointing selection IsEM flag for 50 GMSB events, for various photon ID requirements. Shown is a decimal representation of a bitwise record of failed photon/electron ID criteria

6. Next steps for UCSC work: Need to have at least a crude validation between release 13 and 14 on signal MC  truth matching also needs to be explored (GHIT vs. proximity) Establish “non-pointing photon DPD” (private package) Add in conversions, explore efficiency and conversion radius resolution Understand if and how conversion information can enhance understanding of GMSB parameters. Plan to begin every-other-weekly phone/EVO meetings with non-pointing photon group