FLUKA simulations of machine-induced background from beam-halo for HL-LHC
Last updated: 4/4/2014
Assumptions used in simulations:
- machine configuration:
- 7 TeV,
- beta*=15cm, optics version HL-LHC 1.0,
- nominal collimator settings - TCTs at 8.3 sigma
- Layout in the FLUKA model (L. Esposito, A. Lechner, N.V. Shetty et al).:
- TCTs assumed to be located 131.8/133.5 m from the IP
- the assumed TAN aperture used in the FLUKA model (elliptical, with H and V semi-axes of 4.1 cm
and 3.7cm) is not the final one, and the TAN vacuum chambers for both
beams were assumed to be parallel (which will not be the case)
- 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 (R. Bruce et al.)
- 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:
- Beam-halo, IR1 (B1 SixTrack distribution on TCTs, B2 FLUKA geometry used). Simulation done by Regina Kwee and Roderik Bruce
Data file of particles at the interface plane (7 380 000 events on the TCTs simulated in FLUKA)
SixTrack conversion factor: 1.7e-4 TCT hits per hit on primary collimator
- Beam-halo, IR5: (B1 SixTrack distribution on TCTs, B2 FLUKA geometry used). Simulation done by Nikhil Shetty and Anton Lechner (*)
Data file of particles at the interface plane (982 400 events on the TCTs simulated in FLUKA, 3200 events per file)
SixTrack conversion factor: 3.5e-5 TCT hits per hit on primary collimator
(*) IR5 files updated in July 2014 to correct geometry error (in addition, beam screen was changed to early 2014 version)
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)