"Adopted" Wisconsin Student I was a PhD student with Klaus - PowerPoint PPT Presentation

"Adopted" Wisconsin Student • I was a PhD student with Klaus Wick at the University of Hamburg ‣ build a small detector component for my masters ‣ continued on to do a physics analysis for my PhD • my advisor at Hamburg didn’t "do" physics analysis ‣ encouraged me to look elsewhere for support ‣ Wisconsin group was a good fit for me ‣ my advisor knew Wesley for his hardware expertise • assumed he would be just as good at analysis • became a Wisconsin student in many ways ‣ moved into the Wisconsin office, joined the group meetings… ‣ regular discussions with all Wisconsin students ‣ Wesley was one of two members of my defense committee Nils Krumnack (Iowa State University) 1

Physics Analysis • measured α S in trijet to dijet cross section ratio in DIS ‣ ratio of α S2 to α S processes ‣ used "new" NLO calculations for α S2 processes ZEUS • exact same analysis as Liang Li d σ / dQ 2 (pb/GeV 2 ) a) ZEUS (prel.) 98-00 Dijets ‣ ZEUS had policy of two 
 ZEUS (prel.) 98-00 Trijets 10 Energy Scale Uncertainty independent analysises 1 ‣ meant as cross check 
 -1 10 against mistakes -2 M n-jet > 25 GeV 10 • many afternoons/evenings 
 NLO (1 + δ hadr ) : O( α s2 ) NLO (1 + δ hadr ) : O( α s3 ) -3 10 of analysis comparisons data / theory b) – 1.5 2 / (Q 2 +E 2 ) < 1 Dijets / NLO : O( α s2 ) NLO : 1/16 < µ r T ‣ cut flows, event dumps, … 1.25 1 0.75 • graduated year ahead of Liang 1.6 data / theory c) – 2 / (Q 2 +E 2 ) < 1 Trijets / NLO : O( α s3 ) NLO : 1/16 < µ r 1.4 T ‣ he finished up the publication 1.2 1 0.8 0.6 2 3 10 10 Q 2 (GeV 2 ) Nils Krumnack (Iowa State University) 2

Hardware Work • did hardware project before joining Wisconsin group ‣ small calorimeter inside accelerator magnet ‣ part of the luminosity system ‣ tagging electrons from ep->ep γ • had a little cooling accident during my PhD ‣ turns out machinable tungsten 
 can rust… ‣ needed complete rebuilding • Wisconsin students got involved in 
 rebuilding the detector: ‣ helped in reassembling the detector ‣ participated in test beam measurements Nils Krumnack (Iowa State University) 3