Clarence Chang CDMS Collaboration Meeting Feb 11-12, 2005 UCSB R118 Odds and Ends Clarence Chang CDMS Collaboration Meeting Feb 11-12, 2005 UCSB

Outline Efficiency variations in time Leakage numbers PRD

Outline Efficiency variations in time Leakage numbers PRD

What we want to do Estimate the impact on our efficiencies due to potential time variations and differences between calibration and WIMP search data Problem : Few Nuclear Recoils in the WIMP search data Proposal : Use Electron Recoils Take pass fraction from ER band cut as estimate of variation in NR band cut efficiency Need to be trickier with timing parameters Bin WIMP search data into 5 time bins and compare with Cf data

Approach for Timing parameters

The Algorithim Fit NR and ER of Cf data to Gaussians Fit ER of WIMP search data to Gaussian Determine a shift and a stretech parameter to match Cf ER Gaussian to WIMP search Gaussian ERµWIMP = ERµCf + ∆µ ERWIMP = ERCf∆ Shift and Stretch timing parameter by  = ( - NRµCf ) ∆ + NRµCf + ∆µ What fraction passes the timing cut?

The Efficiencies

Relative Differences

Average over Time bins

Relative Difference (Averaged over time)

Outline Efficiency variations in time Leakage numbers PRD

Single Scatter Gammas From sample from which Timing cuts are not defined Z1 : 1/21,725 ~ 0.0046% Z2+3+5 : 0/13,632 (4064+3477+6091) <0.017% (90% UL) Single scatter gammas in WIMP search data Z1 has 1,702 events Z2+3+5 have 4,528 (1017+1283+2228) Expected 0.08 events (in Z1)

Neutrons MC simulations from Sharmila Include more than MC for SUF… so have new numbers! Coincident neutrons : 1.9 0.4 Anti-Coincident (punch through) neutrons : 0.05 0.02

Betas Using data from which timing cut is defined Recoil Z1 Z2 Z3 Z5 10-20 - 0.11 0.16 0.08 20-40 0.03 0.25 0.12 40-100 0.02 0.1 0.04 Using data from which timing cut is defined Recoil Z1 Z2 Z3 Z5 10-20 - 20-40 0.03 0.14 40-100 Using data from which timing cut is not defined

Expected leakage summary Neutrons : 0.050.02 Ambient gammas : 0.07 Betas : 1.05 0.36

Outline Efficiency variations in time Leakage numbers PRD

Blind vs Intended analysis? What plots to show Only Z5’s Qinner efficiency varies. All others the same. Will show difference for Z5 Qin. This is moot. Both for overall efficiency and limits Scatter plots? (blind, intended, both?) Cut numbers? (blind, intended, both?) Arguments for showing only intended analysis Can anyone outside of me reconstruct the blind analysis easily? Are these RQs available? Will we make these RQs public? Arguments for showing only the blind analysis More consistent with PRL story Still, really just arguing over wording “Oh, you just f**ked up, but it didn’t matter…”