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ApprovedPlotsTileTiming

Introduction

Tilecal public plots from the timing studies

Timing calibration

Laser events, time stability monitoring during Run-2

The reconstructed time in all Tile Calorimeter channels is monitored during the physics runs with laser calibration events shot during empty bunch crossings. In Run-2, TileCal suffered from sudden changes in time settings (typically in a group of six channels) as demonstrated on the top plot for channels 30--35 of the EBC09 module (run 325790, express stream). The dashed line indicates the expected mean time value. Laser events were used for correcting the physics reconstructed time during the calibration loop, still before physics data are processed. The reconstructed time in laser events after applying the timing jump correction is shown in the bottom plot (run 325790, blk stream).
Contact: tomas.davidek@cern.ch , michaela.mlynarikova@cern.ch

Date: July, 2020


png , eps

png , eps

The mean reconstructed amplitude, relative to the results of the first run of each type, in standalone laser calibration runs and laser-in-gap events (top) and the mean reconstructed time in laser-in-gap events (bottom). All results are shown as a function of the run number in the affected channel. The change in the amplitude and time corresponds to a moment when the 3-in-1 card got damaged.
Contact: tomas.davidek@cern.ch , michaela.mlynarikova@cern.ch

Date: July, 2020


png , eps

png , eps

Single beam, 2015 splash events

Timing of ATLAS TileCal signals recorded with single beam data on April 2015 (Beam 2, entering C-side, Z<0, splash events). The average time over all cells with the same phi (azimuth) coordinate is shown as a function of the cell Z (along beam axis) coordinate, for all three radial samplings (represented with different colors). Timing corrections based on laser data had been applied. The observed slope matches the time the particles take to cross the calorimeter along the Z direction.
Contact: luca.fiorini@cern.ch

[eps] [png]
Timing of ATLAS TileCal signals recorded with single beam data on April 2015 (Beam 1, entering A-side, Z>0 and Beam 2, entering C-side, Z<0, splash events). The average time over all cells with the same phi (azimuth) coordinate is shown as a function of the cell Z coordinate (along beam axis) coordinate, for all three radial samplings (represented with different colors). Timing corrections based on laser data had been applied. After applying the time of flight correction that assumes a track parallel to the Z-axis we obtain a flat distribution (within 1.5 ns), demonstrating the good time equalization.
Contact: luca.fiorini@cern.ch

[eps] [png]
Timing of ATLAS TileCal signals recorded with single beam data on April 2015 (Beam 1, entering A-side, Z>0 and Beam 2, entering C-side, Z<0, splash events). Cell time distribution over several events, after removing ~2% of cells without a proper time calibration (mean=-0.34ns , RMS=1.20ns). Entries below -3ns and above 3ns are not shown, but all entries enter in the calculation of the mean and RMS of the distribution. The values of the mean and RMS reflect the replacement of the electronics which happened during the maintenance work of the Long Shutdown. The timing offsets measured with splash events will be introduced in the ATLAS condition database and used in the reconstruction of the TileCal signals.
Contact: luca.fiorini@cern.ch

[eps] [png]
Energy of TileCal signals recorded with single beam data in April 2015 (Beam 1, entering A-side, Z>0 and Beam 2, entering C-side, Z<0). The average energy of the cells is represented as a function of the pseudo-rapidity, η, and the azimuthal coordinate, φ. The regions with minima correspond to the shadow of the endcap toroid magnets. In the above figure the vertical separations delineate the boundaries between TileCal modules.
Contact: luca.fiorini@cern.ch

[eps] [png]
Energy density of TileCal signals recorded with single beam data in April 2015 (Beam 1, entering A-side, Z>0 and Beam 2, entering C-side, Z<0). The average energy density of the cells is represented as a function of the pseudo-rapidity, η, and the azimuthal coordinate, φ. The regions with minima correspond to the shadow of the endcap toroid magnets. In the above figure the vertical separations delineate the boundaries between TileCal modules.
Contact: luca.fiorini@cern.ch

[eps] [png]

Single beam, 2011 splash events

Timing of Atlas. TileCal signals recorded with single beam data on February 2011 (Beam 2, entering C-side, Z<0; 9 splash events). The average time over all cells with the same phi (azimuth) coordinate is shown in function of the cell Z (along beam axis) coordinate, for all three radial samplings (represented with different colors). Timing corrections based on laser data had been applied. The observed slopes match the time the muons take to cross the calorimeter along the Z direction.
Contact: mvolpi@ifae.es

[png]
Timing of Atlas. Timing of TileCal signals recorded with single beam data on February 2011 (Beam 2, entering C-side, Z<0; 9 splash events). The average time over all cells with the same phi (azimuth) coordinate is shown in function of the cell Z (along beam axis) coordinate, for all three radial samplings (represented with different colors). Timing corrections based on laser data had been applied. After applying the time of flight correction that assumed a track parallel to the Z-axis we obtain a flat distribution (within 1 ns), demonstrating the good time equalization.
Contact: mvolpi@ifae.es

[png]
Timing of Atlas. Timing of TileCal signals recorded with single beam data on February 2011 (Beam 2, entering C-side, Z<0; 9 splash events). Cell time distribution over several runs, after removing ~2% of cells without a proper time calibration (mean=0.080ns, RMS=0.50ns)
Contact: mvolpi@ifae.es

[png]

Single beam, 2010 splash events

Timing of TileCal signals recorded with single beam data on February 2010 (Beam 1, entering A-side, Z>0). The average time over all cells with the same phi (azimuth) coordinate is shown in function of the cell Z (along beam axis) coordinate, for all three radial samplings (represented with different colors). Timing corrections based on laser data had been applied. The observed slopes match the time the muons take to cross the calorimeter along the Z direction.
Contact: succurro@ifae.es

[png]
Timing of TileCal signals recorded with single beam data on February 2010 (Beam 1, entering A-side, Z>0). The average time over all cells with the same phi (azimuth) coordinate is shown in function of the cell Z (along beam axis) coordinate, for all three radial samplings (represented with different colors). Timing corrections based on laser data had been applied. After applying the time of flight correction that assumed a track parallel to the Z-axis we obtain a flat distribution (within 1 ns), demonstrating the very good time equalization. Bottom right plot: Cell time distribution, after removing ~3% of cells without a proper time calibration (mean=-0.03ns , RMS=0.45ns).
Contact: succurro@ifae.es

[png]
Timing of TileCal signals recorded with single beam data on February 2010 (Beam 1, entering A-side, Z>0). Cell time distribution over several runs, after removing ~3% of cells without a proper time calibration (mean=-0.03ns , RMS=0.45ns).
Contact: succurro@ifae.es

[png]

Cosmic muon and splash events (2008, 2009)

The difference of time offsets seen in the single beam (10 September 2008) and cosmic (run 91387 11 October 2008 RPC trigger) data is shown for the Tile second and third radial layers. First layer of Tile calorimeter (A cells) was excluded from the analysis because of the low precision observed in the reconstruction of the signal in the cosmic data. Final comparison between the two measurements is possible in 77% of the total sample of BC and D cells. Presented quantity compares the per cell relative timing in Tile calorimeter seen in the single beam to the timing seen in the cosmic data, and corresponds to the mean of (-0.54+-0.03) ns and sigma of (1.02+0.02) ns. Hence, two measurements agree within 2ns on per cell level.
Contact: Joao Gentil Saraiva gentil@lip.pt
Reference:ATL-COM-TILECAL-2009-024
UPDATED: 12 Nov 2009
fig36a_TimeOffsetsCorrelation_09Apr2010.png
[B&W png] [B&W eps] [Color png] [Color eps] fig36b_TimeOffsetDifferenceHistogram_09Apr2010.png
[png] [eps]
Difference in time offset averages per module between the values measured with 2008 cosmic muon (run 91387 from CosmicDownwardMuons stream) and single beam data. The comparison is shown including only cells from the second and third radial layer. The first radial layer is not included here due to the lower accuracy of measurements done with cosmic muons (check plot with the cosmic muons absolute values also in this twiki). For the EBC partition, the number of cells for which it was possible to obtain a measurement with cosmic data was very small for modules 10-30 resulting in a low statistical precision. There are no measurements for module 42 in EBC partition, module 46 in EBA partition and modules 13 and 17 in LBC partition.
Contact: Joao Gentil Saraiva gentil@lip.pt
Reference:ATL-COM-TILECAL-2009-024
fig35b_TimeCosBeaDiff_2nd3rd_09Apr2010.png
[eps] [png]
Online monitoring of Cosmic-ray muon events triggered with L1Calo during a 2009 cosmic-ray run. The y axis shows the average of hit cell times corrected for the time-of-flight along the reconstructed track, taking the horizontal plane y=0 as reference. The x axis shows the z coordinate of the track's intersection with the horizontal plane. Each entry in the distribution identifies a single cosmic-ray muon track reconstructed with the TileMuonFitter algorithm. Since the only input into this algorithm are quantities reconstructed in the Tile Calorimeter, the flat response in time demonstrates that the synchronization of the Tile Calorimeter channels was well established using the laser calibration and the single beam data from 2008. The poorer response for high values of |z| results uniquely from poorer statistics.
Contact: Joao Gentil Saraiva gentil@lip.pt
Reference: Missing
tmftime_oct09_r135926_L1Calo
[eps] [png]


Major updates:
-- HenricWilkens - 08-Aug-2013

Responsible: HenricWilkens
Subject: public

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Topic revision: r7 - 2020-10-27 - MichaelaMlynarikova
 
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