FLUKA simulations of machine-induced background from beam-halo for HL-LHC
Last updated: 7/11/2016
Assumptions used in simulations:
- machine configuration:
- 7 TeV,
- beta*=15cm, optics version HL-LHC 1.0, half-crossing-angle of 295 microrad, round beams
- nominal collimator settings - TCTs at 8.3 sigma
- 2sigma-retracted settings - TCTs at 10.5 sigma
- Layout in the FLUKA model (L.S. Esposito, F. Cerutti, A. Lechner):
- TCTs assumed to be located 131.8/133.5 m from the IP, added TCT5s around 213 m (as part of new baseline)
- implemtented short TAN (2.5 m)
- freeze D2 aperture
- The concrete shielding blocks (JSCA), which are currently installed between D1 and TAN, were not included in the simulations since they are
not yet defined
- Interface plane at 22.6m from IP, where all particles are scored
- starting conditions on the TCTs in both planes produced with SixTrack simulations
- Normalization:
- all secondary particles which have the
same event number (column 1), originate from the *same*
TCT hit and hence they have to be loaded together
- Cutoff at 20 MeV
Data files with particles entering the interface plane:
- Case 1: Beam-halo, IR1, B1, Fluka HLv1.1, SixTrack HLv1.0, updated nominal collimator settings SixTrack+Fluka simulations done by Regina Kwee
Data file of particles at the interface plane (4,257,000 events on the TCTs simulated in FLUKA)
SixTrack conversion factor: 7.7e-4 TCT hits per lost particle
- Case 2: Beam-halo, IR1, B1, Fluka HLv1.1, SixTrack HLv1.0, 2-sigma retracted collimator settings SixTrack+Fluka simulation done by Regina Kwee
Data file of particles at the interface plane (5,319,000 events on the TCTs simulated in FLUKA)
SixTrack conversion factor: 1.05e-4 TCT hits per lost particle
- Case 3: Beam-halo, IR1, B2, Fluka HLv1.1, SixTrack HLv1.0, 2-sigma retracted collimator settings SixTrack+Fluka simulation done by Regina Kwee
Data file of particles at the interface plane (5,315,000 events on the TCTs simulated in FLUKA)
SixTrack conversion factor: 1.01e-4 TCT hits per lost particle
- Case 4: Crab-cavity failure, phase shift on outgoing B1 in IR1, Fluka HLv1.1, SixTrack HLv1.0, nominal collimator settings SixTrack simulations done by Andrea Santamaria and Kyrre Sjobaek, Fluka simulations by Regina Kwee
Data file of particles at the interface plane (4,901,000 events on the TCTs simulated in FLUKA)
Data columns in the files:
- primary event number
- FLUKA particle type ID
- particle generation number
- Stastical weight
- x (cm)
- y (cm)
- directional cosine w.r.t X-axis
- directional cosine w.r.t Y-axis
- Total energy (GeV)
- Kinetic energy (GeV)
- particle age since primary event (sec)
- x coordinate of initial inelastic proton interaction in TCT or on beam-gas (cm)
- y coordinate of initial inelastic proton interaction in TCT or on beam-gas (cm)
- z coordinate of initial inelastic proton interaction in TCT or on beam-gas (cm)
Note, case 1 and 4 have the column 2 and 3 swaped.