Fast ADT test: dependency of the simulated energy deposition on the - PowerPoint PPT Presentation

Fast ADT test: dependency of the simulated energy deposition on the loss distribution N. Shetty, A. Lechner ( on behalf of the FLUKA team ) and with contributions from V. Chetvertkova, A. Priebe Quench-Test Analysis Working Group Meeting October 18, 2013 1 / 11

Part 1: Loss distributions from MADX 2 / 11

PART 1/2: Loss distributions from MADX Comparison of loss distributions Comparison of loss distributions × 3 10 250 case 73 case 73 ( most realistic ): protons/m (arbitrary normalization) case 61 ◮ Tune was matched 200 case 59 ◮ Bump was applied (the 150 exact order as in experiment) 100 ◮ MQ errors considered 50 case 61: 0 ◮ Extreme impossible case -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 Distance from center of MQ.12L6 ( m ) [ Beam2 <----- ] of third integer tune ◮ Bump was applied case 73 250 case 61 case 59 case 59 ( base ): 200 rad) ◮ Bump was applied µ xprime ( 150 ◮ Tune was matched 100 afterwards, which was 50 not done in the 0 experiment. 0 0.2 0.4 0.6 0.8 1 1.2 1.4 Distance from center of MQ.12L6 ( m ) [ Beam2 <----- ] 3 / 11

Case 59 (also shown during previous presentation) Comparison of Beam-2 BLM Signals (case 59) × 6 10 35 8 Measurement 7 30 BLM dose simulation FLUKA Source impact ( protons/m ) 6 25 based on the original BLM dose ( mGy ) 5 20 loss distribution (source) 4 for 8.2 × 10 8 protons 15 3 10 2 5 1 BLM simulation and 0 0 -6 -4 -2 0 2 4 6 measurement agree very Distance from center of MQ.12L6 ( m ) [ Beam2 <----- ] 3 Longitudinal energy density ( mJ/cm ) well × 6 10 250 20 18 Source impact ( protons/m ) Max. energy density in 200 16 14 MQ.12L6 (until quench) 150 12 is ∼ 250 mJ/cm 3 , for 10 100 8 5 × 10 8 protons 6 50 4 2 0 0 -150 -100 -50 0 50 100 150 Distance from MQ.12L6 ( cm ) [ Beam2 <----- ] 4 / 11

PART 1/2: BLM dose comparison Comparison of Beam-2 BLM Signals ( case73 ) Comparison of Beam-2 BLM Signals ( case61 ) × 6 × 6 10 10 8 8 35 70 Measurement Measurement 7 7 FLUKA FLUKA Source impact ( protons/m ) Source impact ( protons/m ) 30 60 6 6 BLM dose ( mGy ) BLM dose ( mGy ) 25 50 5 5 20 40 4 4 15 30 3 3 10 20 2 2 5 1 1 10 0 0 0 0 -6 -4 -2 0 2 4 6 -6 -4 -2 0 2 4 6 Distance from center of MQ.12L6 ( m ) [ Beam2 <----- ] Distance from center of MQ.12L6 ( m ) [ Beam2 <----- ] Simulation and measurement agree very well 5 / 11

PART 1/2: Longitudinal peak energy density Max energy density in Longitudinal peak energy density in inner coil (normalized per 5e8 protons) 300 case 59 case 73 the range of ∼ 250 - 280 case 61 mJ/cm 3 250 200 For case 61, increase in mJ / cm 3 150 energy density is not proportional to increase 100 in local loss density as 50 the horizontal impact 0 angle is smaller -200 -150 -100 -50 0 50 100 150 z ( cm ) [ distance from center of MQ.12L6 ] 6 / 11

Part 2: Loss distributions (artificially stretched) 7 / 11

PART 2/2: Loss distributions (artificially stretched) Comparison of loss distributions (artificially stretched) Comparison of loss distributions (artificially stretched) × -6 10 Source length doubled 50 case 59 45 while maintaining the protons/m (arbitrary normalization) source-stretched-upstream 40 same total intensity source-stretched-upstream-shifted80cm 35 30 Artificial manipulation to 25 study the effect of 20 15 stretched source on BLM 10 signal and energy 5 density 0 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 Distance from center of MQ.12L6 ( m ) [ Beam2 <----- ] 8 / 11

PART 2/2: BLM dose comparison (artificially stretched) Comparison of Beam-2 BLM Signals ( source-extended-upstream ) Comparison of Beam-2 BLM Signals ( source-extended-upstream-shifted80cm ) × 6 × 6 10 10 8 8 Measurement 16 Measurement 16 7 7 FLUKA FLUKA Source impact ( protons/m ) Source impact ( protons/m ) 14 14 6 6 BLM dose ( mGy ) BLM dose ( mGy ) 12 12 5 5 10 10 4 4 8 8 3 3 6 6 2 2 4 4 1 1 2 2 0 0 0 0 -6 -4 -2 0 2 4 6 -6 -4 -2 0 2 4 6 Distance from MQ.12L6 ( m ) [ Beam2 <----- ] Distance from MQ.12L6 ( m ) [ Beam2 <----- ] Still the simulation and measurement agree 9 / 11

PART 2/2: Longitudinal peak energy density (artificially stretched) Energy density Longitudinal peak energy density in inner coil (normalized per 5e8 protons) 300 case 59 decreases for stretched source-extended-upstream source-extended-upstream-shifted80cm 250 sources (while no proportional decrease in 200 BLM dose) mJ / cm 3 150 Max energy density 100 decreases from ∼ 250 50 mJ/cm 3 to ∼ 160 - 170 0 mJ/cm 3 -200 -150 -100 -50 0 50 100 150 z ( cm ) [ distance from center of MQ.12L6 ] 10 / 11

Conclusions BLM signal remains more or less the same for different loss distributions (the shower is smeared out at the BLMs because they are located farther laterally) Energy density in the coil is sensitive to the local loss density and horizontal impact angle of the loss distributions (because of the proximity of the coil to the cascade development) 11 / 11