Study of Strip Tracker Barrel TrackingRecHit Position Resolution

The resolution was studied by Ian Tomalin & Matthew Kirk (RAL) using the CMSSW 6.1.1 validation code Validation/RecoTrack/plugins/SiStripTrackingRecHitsValid.cc running on simulated particle gun muons of Pt = 1, 10 & 100 GeV. The resolution is obtained from the residual between the reconstructed and generated hits.

The goal was to check the resolution numbers in Table 1 of PAPER TRK-11-001 which were obtained using a data driven method (using on overlaps between sensors).

Two sets of results were obtained, using two different definitions of the resolution

Main Results (Barrel + Endcap)

The residual histogram was truncated at +- 2 * strip pitch. The RMS width was evaluated in this range. A likelihood fit of a gaussian was then made to the histogram in the range +- 2 * RMS. Likelihood fits are vulnerable to non-gaussian tails.

The following sets of histograms each contain: (i) Hit position residual distributions; (ii) Mean abs hit position residual vs. rapidity; (iii) Mean abs hit position residual vs. track width (related to the angle at which the track crosses the silicon). All histograms are made seperately for each cluster width and barrel layer/endcap ring.

Alternative results (Barrel only).

These differ from the "Main Results" in that a chi2 fit was made to the histogram instead of a likelihood fit, in the range +- 3 * RMS. N.B. In chi2 fits, ROOT ignores bins with no entries, which can lead to an overestimate of the resolution if the residual distribution is square in shape instead of gaussian. (Happens for cluster width = 1 or 3).

The following sets of histograms each contain: (i) Hit position residual distributions; (ii) Mean abs hit position residual vs. rapidity; (iii) Mean abs hit position residual vs. track width (related to the angle at which the track crosses the silicon). All histograms are made seperately for each cluster width and barrel layer.

Topic attachments
I Attachment History Action Size Date Who Comment
Unknown file formatdocx HitResSummary.docx r2 r1 manage 23.4 K 2013-08-29 - 18:06 IanTomalin test
PDFpdf HitResSummary.pdf r4 r3 r2 r1 manage 314.2 K 2013-08-29 - 18:06 IanTomalin test
Unknown file formatdocx HitResSummaryLikelihood.docx r2 r1 manage 27.2 K 2013-08-29 - 18:06 IanTomalin likelihood
PDFpdf HitResSummaryLikelihood.pdf r2 r1 manage 343.1 K 2013-08-29 - 18:06 IanTomalin likelihood
PDFpdf Res_100_GeV_TID_TEC-likelihood.pdf r1 manage 180.3 K 2013-08-29 - 17:55 IanTomalin likelihood
PDFpdf Res_100_GeV_TOB_TIB-likelihood.pdf r1 manage 178.0 K 2013-08-29 - 17:55 IanTomalin likelihood
PDFpdf Res_10_GeV_TID_TEC-likelihood.pdf r1 manage 182.3 K 2013-08-29 - 17:55 IanTomalin likelihood
PDFpdf Res_10_GeV_TOB_TIB-likelihood.pdf r1 manage 178.9 K 2013-08-29 - 17:55 IanTomalin likelihood
PDFpdf Res_1_GeV_TID_TEC-likelihood.pdf r1 manage 180.5 K 2013-08-29 - 17:55 IanTomalin likelihood
PDFpdf Res_1_GeV_TOB_TIB-likelihood.pdf r1 manage 179.9 K 2013-08-29 - 17:55 IanTomalin likelihood
PDFpdf Resolution_100_GeV.pdf r1 manage 178.7 K 2013-08-15 - 12:31 IanTomalin test
PDFpdf Resolution_10_GeV.pdf r1 manage 179.2 K 2013-08-15 - 12:31 IanTomalin test
PDFpdf Resolution_1_GeV.pdf r1 manage 180.2 K 2013-08-15 - 12:31 IanTomalin test
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Topic revision: r3 - 2013-08-29 - IanTomalin
 
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