Difference: RadiationSimulationPublicResults (20 vs. 21)

Revision 212019-05-31 - IanDawson

Line: 1 to 1
 
META TOPICPARENT name="WebHome"
AtlasPublicTopicHeader.png
Line: 21 to 21
  In run 2 total the delivered luminosity is estimated to 160 3 fb-1. This is slightly higher than the normally reported luminosity delivered in stable beams because for radiation exposure also the collisions outside of stable beam conditions have to be accounted for.
Changed:
<
<
Simulation results are from a dataset of 50000 events generated by Pythia 8 with minimum bias tune A3 [3] and an assumed inelastic cross section of 78.42 mb at √s=13 TeV. The events were processed with FLUKA 2011 or Geant 4 [1,2] with the shielding physics list. A description of the ATLAS FLUKA simulation framework can be found in [4]. The geo tag for the Geant4 results is ATLAS-R2-2016-01-01-00.
>
>
Simulation results are from a dataset of 50000 events generated by Pythia 8 with minimum bias tune A3 [1] and an assumed inelastic cross section of 78.42 mb at √s=13 TeV. The events were processed with FLUKA 2011 [2,3] or Geant 4 [4,5] with the shielding physics list. A description of the ATLAS FLUKA simulation framework can be found in [6]. The geo tag for the Geant4 results is ATLAS-R2-2016-01-01-00.
  The simulations are based on 3D models (simplified in case of FLUKA), but the radiation maps are averaged in azimuth. Not included in the simulated predictions are the systematic uncertainties associated withthe event generator, Geant4/FLUKA physics models, geometry description accuracies and the damage factors in deriving 1 MeV neutron equivalent fluences. The present estimate for the combined uncertainty from these sources is 50% in the ID volume, but assumed larger in the calorimeter and muon detector regions.
Changed:
<
<
[1] GEANT4 Collaboration, GEANT4: a simulation toolkit, Nucl. Instrum. Meth. A 506 (2003) 250.
[2] ATLAS Collaboration, The ATLAS Simulation Infrastructure, Eur. Phys. J. C 70 (2010) 823, arXiv: arXiv:1005.4568 [physics.ins-det].
[3] ATLAS Collaboration, A study of the Pythia 8 description of ATLAS minimum bias measurements with the Donnachie-Landshoff diffractive model, ATL-PHYS-PUB-2016-017, https://cds.cern.ch/record/2206965
[4] S. Baranov et al., Estimation of Radiation Background, Impact on Detectors, Activation and Shielding Optimization in ATLAS, (2005), url: https://cds.cern.ch/record/814823.
>
>
[1] ATLAS Collaboration, "A study of the Pythia 8 description of ATLAS minimum bias measurements with the Donnachie-Landshoff diffractive model", ATL-PHYS-PUB-2016-017, https://cds.cern.ch/record/2206965
[2] "The FLUKA Code: Developments and Challenges for High Energy and Medical Applications", T.T. Bohlen, F. Cerutti, M.P.W. Chin, A. Fasso`, A. Ferrari, P.G. Ortega, A. Mairani, P.R. Sala, G. Smirnov, and V. Vlachoudis, Nuclear Data Sheets 120, 211-214 (2014)
[3] "FLUKA: a multi-particle transport code", A. Ferrari, P.R. Sala, A. Fasso`, and J. Ranft, CERN-2005-10 (2005), INFN/TC_05/11, SLAC-R-773
[4] GEANT4 Collaboration, GEANT4: a simulation toolkit, Nucl. Instrum. Meth. A 506 (2003) 250.
[5] ATLAS Collaboration, The ATLAS Simulation Infrastructure, Eur. Phys. J. C 70 (2010) 823, arXiv: arXiv:1005.4568 [physics.ins-det].
[6] S. Baranov et al., Estimation of Radiation Background, Impact on Detectors, Activation and Shielding Optimization in ATLAS, (2005), url: https://cds.cern.ch/record/814823.
 

<!-- border=1 cellpadding=10 cellspacing=10>                                  -->
Line: 44 to 46
 The total delivered luminosity in run 2 is estimated to 160 3 fb-1 .

The simulations are based on 3D models (simplified in case of FLUKA), but the radiation maps are averaged in azimuth.

Changed:
<
<
Not included in the simulated predictions are the systematic uncertainties associated with event generator, Geant4/FLUKA physics models, geometry description accuracies. The present estimate for the combined uncertainty from these sources for dose estimates in the ID is 50%.
>
>
Not included in the simulated predictions are the systematic uncertainties associated with event generator, Geant4/FLUKA physics models, geometry description inaccuracies. The present estimate for the combined uncertainty from these sources for dose estimates in the ID is 50%.
 

Line: 70 to 72
 The total delivered luminosity in run 2 is estimated to 160 3 fb-1 .

The simulations are based on 3D models (simplified in case of FLUKA), but the radiation maps are averaged in azimuth.

Changed:
<
<
Not included in the simulated predictions are the systematic uncertainties associated with event generator, Geant4/FLUKA physics models, geometry description accuracies and the damage factors in deriving 1 MeV neutron equivalent fluences. The present estimate for the combined uncertainty from these sources for fluence estimates in the ID is 50%.
>
>
Not included in the simulated predictions are the systematic uncertainties associated with event generator, Geant4/FLUKA physics models, geometry description inaccuracies and the damage factors in deriving 1 MeV neutron equivalent fluences. The present estimate for the combined uncertainty from these sources for fluence estimates in the ID is 50%.
 

Line: 96 to 98
 The total delivered luminosity in run 2 is estimated to 160 fb-1 3 fb-1 .

The simulations are based on 3D models (simplified in case of FLUKA), but the radiation maps are averaged in azimuth.

Changed:
<
<
Not included in the simulated predictions are the systematic uncertainties associated with event generator, Geant4/FLUKA physics models, geometry description accuracies and the damage factors in deriving 1 MeV neutron equivalent fluences. The present estimate for the combined uncertainty from these sources for fluence estimates in the ID is 50%.
>
>
Not included in the simulated predictions are the systematic uncertainties associated with event generator, Geant4/FLUKA physics models, geometry description inaccuracies and the damage factors in deriving 1 MeV neutron equivalent fluences. The present estimate for the combined uncertainty from these sources for fluence estimates in the ID is 50%.
 

Line: 120 to 122
 Error bars on simulation (Geant4 and Fluka) points are standard deviations of simulated doses and fluences per fb-1 in intervals of coordinatesaround monitoringlocation:r:1cm,z:4cmonPST, r:2cm,z:3cmontheIDEndPlateandr:2cm,z:4cmonthe cryostat wall.

The simulations are based on 3D models (simplified in case of FLUKA), but the radiation maps are averaged in azimuth.

Changed:
<
<
Not included in the simulated predictions are the systematic uncertainties associated with event generator, Geant4/FLUKA physics models, geometry description accuracies and the damage factors in deriving 1 MeV neutron equivalent fluences. The present estimate for the combined uncertainty from these sources is 50% for both radiation quantities in the ID region.
>
>
Not included in the simulated predictions are the systematic uncertainties associated with event generator, Geant4/FLUKA physics models, geometry description inaccuracies and the damage factors in deriving 1 MeV neutron equivalent fluences. The present estimate for the combined uncertainty from these sources is 50% for both radiation quantities in the ID region.
 

Line: 138 to 140
 
Changed:
<
<
TID and 1 MeV eq. neutron fluence measured with radiation monitors in the Muon detector during run 2. Doses are measured with LAAS RadFETs (1.6 um thick oxide) and fluences are measured with high sensitivity PiN diodes (CMRP) under forward bias. Sensors are installed on Small Wheels at r ~ 2.1 m and z ~ 6.9 m and on Big Wheels at r ~ 2.1 m and z ~ 6.9 m at four azimuthal angles (0,90,180 and 270) on sides A and C. On Small Wheels 7 out of 8 and on Big Wheels 3 out of 8 sensors were operating during run 2.
>
>
TID and 1 MeV eq. neutron fluence measured with radiation monitors in the Muon detector during run 2. Doses are measured with LAAS RadFETs (1.6 um thick oxide) and fluences are measured with high sensitivity PiN diodes (CMRP) under forward bias. Sensors are installed on Small Wheels at r ~ 2.1 m and z ~ 6.9 m and on Big Wheels at r ~ 2.1 m and z ~ 6.9 m at four azimuthal angles (0,90,180 and 270) on sides A and C. On Small Wheels 7 out of 8 and on Big Wheels 3 out of 8 sensors were operating during run 2.
  Points with error bars represent measured values: points are averages from sensors at same r and z and error bars are calculated as E = √(σ2 + (σcal)2) , where σ is the standard deviation of measurements and σcal = 0.2 *D is the 20% accuracy of calibration. Only one point for every ~ 7 days is shown.

Hatched bands show Geant4 simulation of doses and fluences at monitoring locations. Dose (centre of the band) is calculated as D = Lint ∙ Dnorm where Lint is the integrated luminosity and Dnorm is the fluence per unit of luminosity obtained from simulation at r and z coordinates of monitors. Width of the band represents standard deviation of Dnorm values in 10 cm intervals of r and z coordinates around the monitoring location. The total delivered luminosity in run 2 is estimated to 160 3 fb-1 .

Changed:
<
<
The simulations are based on 3D models (simplified in case of FLUKA), but the radiation maps are averaged in azimuth. Not included in the simulated predictions are the systematic uncertainties associated with event generator, Geant4/FLUKA physics models, geometry description accuracies and the damage factors in deriving 1 MeV neutron equivalent fluences.
>
>
The simulations are based on a 3D model, but the radiation maps are averaged in azimuth. Not included in the simulated predictions are the systematic uncertainties associated with event generator, Geant4 physics models, geometry description inaccuracies and the damage factors in deriving 1 MeV neutron equivalent fluences.
 

Line: 170 to 172
 Error bars on simulation (Geant4 and Fluka) points are standard deviations of simulated doses and fluences per fb-1 in intervals of coordinates around monitoring location: r: 10 cm, z: 10 cm.

The simulations are based on 3D models (simplified in case of FLUKA), but the radiation maps are averaged in azimuth.

Changed:
<
<
Not included in the simulated predictions are the systematic uncertainties associated with event generator, Geant4/FLUKA physics models, geometry description accuracies and the damage factors in deriving 1 MeV neutron equivalent fluences. The large TID difference observed in two of the LAr regions is where the material distribution is particularly complex, with strong variations in azimuth, and this is likely to be oversimplified in the simulations.
>
>
Not included in the simulated predictions are the systematic uncertainties associated with event generator, Geant4/FLUKA physics models, geometry description inaccuracies and the damage factors in deriving 1 MeV neutron equivalent fluences. The large TID difference observed in two of the LAr regions is where the material distribution is particularly complex, with strong variations in azimuth, and this is likely to be oversimplified in the simulations.
 

 
This site is powered by the TWiki collaboration platform Powered by PerlCopyright & 2008-2019 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding TWiki? Send feedback