|
|
| Line 1: |
Line 1: |
| − | == Charged Tracks ==
| |
| − | * <span style="color:#0000FF">DChargedTrackHypothesis</span>::<span style="color:#008000">position</span>() returns the position of the track at its position of closest approach to the beamline.
| |
| − | * <span style="color:#0000FF">DChargedTrackHypothesis</span>::<span style="color:#008000">t1</span>() is the measured hit time of the BCAL/TOF/FCAL hit/shower, if present, that is matched to the track (if hits in multiple systems, order of preference is BCAL/TOF/FCAL).
| |
| − | ** If it is not matched to a hit, it's value is <span style="color:red">NaN</span> (and the detector system is <span style="color:red">SYS_NULL</span>).
| |
| − | * <span style="color:#0000FF">DChargedTrackHypothesis</span>::<span style="color:#008000">pathLength</span>() returns the path length along the track from it's hit in the BCAL/TOF/FCAL to position().
| |
| − | * <span style="color:#0000FF">DChargedTrackHypothesis</span>::<span style="color:#008000">t0</span>() is either:
| |
| − | ** The selected RF bunch time, if present, propagated to <span style="color:#008000">position</span>().
| |
| − | ** The measured start counter hit time, if present, propagated to <span style="color:#008000">position</span>().
| |
| − | ** If neither is available, it's value is <span style="color:red">NaN</span> (and the detector system is <span style="color:red">SYS_NULL</span>).
| |
| − | * <span style="color:#0000FF">DChargedTrackHypothesis</span>::<span style="color:#008000">measuredBeta</span>() is <span style="color:#008000">pathLength</span>()/(<span style="color:red">c</span>*(<span style="color:#008000">t1</span>() - <span style="color:#008000">t0</span>())). Thus it is <span style="color:red">NaN</span> if there aren't enough detector hits on the track.
| |
| − | * <span style="color:#0000FF">DChargedTrackHypothesis</span>::<span style="color:#008000">time</span>() is the hit time from the ST/BCAL/TOF/FCAL system propagated to <span style="color:#008000">position</span>().
| |
| − | ** This propagation is performed step by step along the track, taking into account the energy loss of the particle at each step. Thus, it is not calculated with a constant beta.
| |
| − | * <span style="color:#0000FF">DChargedTrackHypothesis</span>::<span style="color:#008000">dChiSq_Timing</span> is defined as:
| |
| − | ** Δt = <span style="color:#008000">t0</span>() - <span style="color:#008000">time</span>()
| |
| − | ** χ<sup>2</sup> = (Δt/σ<sub>Δt</sub>)<sup>2</sup>
| |
| − | ** With NDF = 1 (0 if not enough matching detectors).
| |
| | | | |
| − | == Neutral Showers ==
| |
