HCAL Timing: Calo Tower timing

Calo Towers carry two times, hcaltime and ecaltime, and three energies: hadenergy (HCAL), emenergy (ECAL) and outerenergy (from HO).

Currently hcaltime t=0 is defined technically as the beginning edge of the first precision sample taken (s₀), in the sense that the phase of the relative bins move the peak from s_-1 to s₀. This imposes an offset with respect to ECAL time, which is defined physically, as the time-of-flight (v=c) from the IP to the center of a tower. Recent changes in CMSSW will allow HCAL timing to be defined this way as well. Until then, a meaningful composite "tower time" would have to be generated manually.

Here are some preliminary plots of CaloTower Timing:

Color plots of Hcal Time vs Tower Energy, Ecal Time vs Tower Energy, and Ecal Time vs Hcal Time:

{{:groups:cms:hcaltiming:cttimes-susylm1-smeared.png?700x200|}}

Color coded plots of Hcal Time vs Tower Energy and Ecal Time vs Hcal Time for different timing windows:

{{:groups:cms:hcaltiming:timesandcts-susylm1-smeared.png?700x200|}}

-- PhilDudero - 15 May 2009