DØ and Hunting the Higgs at Arizona Faculty: Erich Varnes Postdocs: Amitabha Das (departing in January for postdoc at SMU), Xiaowen Lei (joined in Summer 2011), Ruchika Nayyar (joined January 3) Students: Fionbarr O’Grady (half-time, joined in summer 2011) Thanks to DOE for continued strong support of the DØ program!

Physics in 2011 Completed top quark analyses Measurement of W helicity fractions in top quark decays published in PRD Working with CDF on Tevatron combination Paper has been ~ready to go for some time, waiting for final approval from CDF SM is safe on this front Presented as preliminary result in Summer 2011:

Physics in 2011 Example: better c jet identification to reduce Transitioned to Higgs boson search (Varnes, Lei, O’Grady) Looking in ZH  nnbb channel, which is complementary to LHC search (and sensitive at low mass) Contributions include: Increasing signal acceptance (for WH) by improving sensitivity to spurious missing ET and expanding trigger menu Updating analysis software to use newer data and Monte Carlo Studies of optimal use of b ID information (both in terms of statistical and systematic uncertainty) Example: better c jet identification to reduce background

Physics in 2011 Limit on Higgs production cross section from DØ in ZH nnbb shown at EPS’11: Aiming for update at Moriond, followed by publication Additional data + analysis improvements should increase sensitivity by ~30%

Service in 2011 Varnes: DØ algorithms/physics coordinator Preparation of new data reconstruction and MC versions Coordinating selection of subset of data that is being reprocessed for “final” DØ results in summer 2012 One of three nominees for spokesperson in 2011 election Das: shifts, L1MU trigger expert, refined version of fake track discriminant Lei: contributing to b ID studies Focusing on introducing additional information into boosted decision tree used to classify jets Preliminary estimate is ~5% improvement in b ID efficiency for the same background rejection Nayyar: EM ID convener Will oversee measurements of EM ID efficiency on reprocessed data