100 likes | 257 Views
Discussion. Joseph Kroll (Penn) Franco Bedeschi (Pisa) 25 October 2005 9 th (!) CDF B s Mixing Workshop. Issues for Discussion. Have completed 2 nd iteration of CDF m s analysis now have a respectable sensitivity (3 rd best in world) tremendous potential from near term improvements
E N D
Discussion Joseph Kroll (Penn) Franco Bedeschi (Pisa) 25 October 2005 9th (!) CDF Bs Mixing Workshop
Issues for Discussion • Have completed 2nd iteration of CDF ms analysis • now have a respectable sensitivity (3rd best in world) • tremendous potential from near term improvements • What do we include in next (3rd) iteration? • components • who will do the work • what needs to be cross-checked • what is the schedule • What are we going to publish? • this summer agreed we would publish 2nd iteration Goal: produce schedule as in Fall 2004 Kroll and Bedeschi
Components of 3rd Generation Analysis • Add 2005 data • up to September for Winter 2006 results • up to shutdown (March 2006) for Summer 2006 results • Issues • production of ntuples from new data set (especially stream H) • could this become part of production? • Calibration (e.g., dE/dx, Si Alignment, TOF) • QC on reconstruction – need a check list here • higher average luminosity – how does it affect ct, dE/dx etc. • Would like to see yields soon • how has higher luminosity & evolving trigger table affected these? Kroll and Bedeschi
3rd Generation Analysis (continued) • Add more decay modes • Ds* & Ds • large addition of statistics • almost fully reconstructed – still needs K factor • need to refine mass fit – backgrounds more important • Add more trigger paths • dilepton (SUSY) triggers – semileptonic decays with flavor tag • important if other semileptonic triggers are prescaled away • combine semileptonics in lepton + SVT, TTT & dilepton triggers • Aside (for discussion of long term plans) • is muon versus TTT trigger optimal (not)? • what about electrons versus TTT? Kroll and Bedeschi
3rd Generation Analysis (continued) • Add more flavor tags • Main gain here expected in SS(K)T • quantify dilution with Monte Carlo • still do not have 1st pass of systematics for any algorithm • new results on measured particle type fractions (B0, B+, B0s) • how do we use these (and further) results in evaluating systematics? • Opposite side tags • maintaining 2004 capabilities requires dE/dx and CPR for SLT(e) • neural net based soft lepton taggers • neural net opposite side tagger • OSKT • forward tracking for JQT etc. substantial effort here also calibrating for 2005 data Kroll and Bedeschi
3rd Generation Analysis (continued) • Other possible improvements • more refined model of lifetime resolution (near term) • hit level improvements in lifetime resolution (medium/long term) • We need to establish procedure for measuring ms • Amplitude scan versus fitting for ms • floating or constrained dilutions for flavor tags? • The procedure should go through the blessing process Kroll and Bedeschi
Issues for 3rd (& later) Generation • Analysis will have many components, e.g., • partially reconst. semileptonic & hadronic + fully reconst. • trigger paths with and without flavor tag in trigger • semileptonic decays in overlapping trigger paths • combining SST with OST (when OST in trigger path) • There is more to do & less physicists for analysis • Still we must find a way to cross-check crucial components • Collaboration will demand this, we should demand it ourselves • this has served us well in the past, e.g., • 2 complete semileptonic analyses for Winter 2005 • parallel lifetime analysis in Bs! Ds () for Winter 2005 • cross-checks of backgrounds in semileptonics in TTT in Fall 2005 • cross-checks of lifetime scale factors in Fall 2005 Kroll and Bedeschi
Cross-checking the Analysis • Profit from related analyses: • B hadron lifetime measurements • checks mass fits • checks lifetime fits • should demonstrate we can measure lifetimes in decays collected with displaced track triggers • Measurements of particles species produced around B hadrons • allows comparison of data to Monte Carlo • do we see the same excess of kaons around Bs as predicted? • Physicists performing crucial cross-checks • should have their names listed with contact persons on relevant CDFNOTEs put forward for blessing in Bs mixing analysis Kroll and Bedeschi
Publication • For 2nd Generation analysis – we agreed • not to cut corners – go for publication quality (we succeeded) • publish the limit if sensitivity was respectable (it is) • Problem: • limited physicist resources • physicists working on 2nd generation want to work on 3rdnow • do not want to be distracted by godparents asking questions • Proposal: • proceed with publication now – need it for 3rd generation too • young physicists need publication for careers • 3rd iteration might take longer than planned • paper could be written/driven by 3rd party Kroll and Bedeschi
Summary • 2nd generation complete – respectable sensitivity • Main upgrades for 3rd generation (Winter/Summer 06) • add 2005 data • add partially reconstructed hadronic decays • add same side tag • combine semileptonic decays from multiple trigger paths • Must ensure cross-checks of crucial components of analysis • Publication • proceed with publication (short PRD) of 2nd generation • prepares us for expedient publication of 3rd generation Kroll and Bedeschi