Checks of Merlin scattering routine in SixTrack
for LHC
Ye Zou
S. Redaelli, R. Bruce, A. Mereghetti, K. N. Sjoebaek, J. Molson,
H. Garcia, M. Fiascaris
Outline
 Configuration
 Comparison among three versions of SixTrack
 Single-jaw tests
 Conclusions
LHC 2016 configuration
Energy = 6.5 TeV, 𝜷∗ = 40 cm, 𝝌𝐢𝐧𝐠 = 370 μrad (total)
S. Redaelli
Collimator
Setting collision (σ)
TCP IR7
5.5
TCSG IR7
7.5
TCLA IR7
11.0
TCP IR3
15.0
TCSG IR3
18.0
TCLA IR3
20.0
TCSG IR6
8.3
TCDQ IR6
8.3
TCT IR1/5
9.0
TCT IR2
37.0
TCT IR8
15.0
TCL 4/5/6, no Totem
15 / 15 / out
TCL 4/5/6, with Totem
15 / 35 / 20
Initial conditions
 Optics: LHC 2016 configuration(𝜷∗ = 40 cm)
 Versions of SixTrack to be compared:
Standard-SixTrack
MSM-SixTrack (added by J. Molson)
Fluka-SixTrack (data supplied by A. Mereghetti )






4 sceneries: B1_H, B1_V, B2_H, B2_V
10 M particles
200 turns
0.1 m bin size for beam loss pattern
No energy spread
Initial beam distribution:
Simulated plane: 5.5 ~ 5.7 σ, the other plane: 0~ 3 σ
B1_H
Zoom in IR7
Standard-SixTrack
DS1
MSM-SixTrack
DS2
Zoom in IR7
DS3
B1_V
Zoom in IR7
Standard-SixTrack
MSM-SixTrack
Zoom in IR7
B2_H
Zoom in IR7
Standard-SixTrack
DS3
MSM-SixTrack
DS2 DS1
Zoom in IR7
B2_V
Zoom in IR7
Standard-SixTrack
MSM-SixTrack
Zoom in IR7
0.1
0.01
0.001
1E-4
1E-5
1E-6
1
Standard-SixTrack
MSM-SixTrack
Fluka-SixTrack
0.1
0.01
0.001
1E-4
1E-5
1E-6
1E-7
The ratio of beam losses to normal SixTrack
Standard-SixTrack
MSM-SixTrack
Fluka-SixTrack
TC
TP
H.
4
TC TDI L2.B
TP .4L 1
V.4 2.B
TC TCL L2.B1
LIB IA. 1
T .6R 4R2
TC CP.6 2.B
1
TC SG.5L3.B
TC SG L3 1
.
.
TCSG.A4R3 B1
S 5 .B
TC G.B R3. 1
5 B
TCLA.A R3. 1
LA 5R B1
TC .B5 3.B
R 1
L
A
TC .6 3.B
TC LA. R3. 1
T 7 B
TC PH R3.B1
.
TP 4L 1
5
TC V.4L .B1
5
TC TCL.4R .B1
5
TCDQA L.5R .B1
5
TC DQA.A4R .B1
DQ .B4 6.B
TC A.C R6. 1
SP 4R B1
TC .A4 6.B
R 1
TCP.D6 6.B
P L 1
T .C 7.B
TC CP.B6L7. 1
B
S
6
TC G.A L7. 1
B
TCSG.B6L7. 1
B
TC SG.A5L7. 1
B
S
TC G.D5L7. 1
B
TCSG.B4L7. 1
TC SG.A4L7 B1
.
TCSG.A 4L7 B1
.
TC SG.B4R7 B1
.B
S
TC G.D5R7 1
SG 5R .B1
TC .E5 7.B
TC SG. R7. 1
6 B
TCLA.A R7. 1
6 B
TC LA.B R7. 1
B
6
L
A
TC .C R7. 1
L 6 B
TC A.D R7. 1
L 6 B
TC A.A R7. 1
T 7 B
TC PH R7.B1
.
TC TPV 4L8. 1
B
.
TCTPH 4L8.B1
TP .4L 1
V.4 1.B
L1 1
.B1
1
The ratio of beam losses to Standard-SixTrack
TC
L.
TCTCL 4R1
TP .5R .B1
H. 1.B
TC TDI 4L2. 1
TP .4L B1
V.4 2.B
TC TCL L2.B1
LI IA 1
TCB.6R.4R2
TC P.6 2.B
T SG L3 1
TCCSG .5L3.B1
TCSG.A.4R3.B1
.
S
TC G.B5R3 B1
.
TCLA.A5R3 B1
L 5 .B
TCA.B5R3.B1
T LA. R3. 1
TCCLA 6R3 B1
.
.
TCTPH 7R3.B1
TP .4L B1
TC V.4L5.B1
5
L
TC TC .4R .B1
TCDQA L.5R5.B1
TC DQA.A4R5.B1
DQ .B 6
TC A.C4R6.B1
S 4 .B
TCP.A4R6.B1
TCP.D6R6.B1
TCP.C6L7.B1
TC P.B L7 1
.
TCSG.A6L7 B1
.
TCSG.B6L7 B1
TC SG.A5L7.B1
.
TCSG.D5L7 B1
.
TCSG.B4L7 B1
TC SG. 4L7.B1
A
TCSG.A 4L7.B1
TC SG.B4R7.B1
TCSG.D5R7.B1
S 5 .B
TCG.E R7. 1
TC SG 5R7 B1
. .
TCLA.A6R7 B1
.
TC LA.B6R7 B1
.
TCLA.C6R7 B1
.
TCLA.D6R7 B1
.
TCLA.A6R7 B1
.
TCTPH 7R7.B1
TC TPV.4L8 B1
.
.
TCTPH 4L8.B1
TP .4L B1
V.4 1.B
L1 1
.B1
Beam losses rate on collimators
1E-7
10
TC
TP
H.
4
TC TDI L2.B
TP .4L 1
V.4 2.B
TC TCL L2.B1
LIB IA. 1
T .6R 4R2
TC CP.6 2.B
1
TC SG.5L3.B
TC SG L3 1
.
.
TCSG.A4R3 B1
S 5 .B
TC G.B R3. 1
5 B
TCLA.A R3. 1
LA 5R B1
TC .B5 3.B
R 1
L
A
TC .6 3.B
TC LA. R3. 1
T 7 B
TC PH R3.B1
.
TP 4L 1
5
TC V.4L .B1
5
TC TCL.4R .B1
5
TCDQA L.5R .B1
5
TC DQA.A4R .B1
DQ .B4 6.B
TC A.C R6. 1
SP 4R B1
TC .A4 6.B
R 1
TCP.D6 6.B
P L 1
T .C 7.B
TC CP.B6L7. 1
B
S
6
TC G.A L7. 1
B
TCSG.B6L7. 1
B
TC SG.A5L7. 1
B
S
TC G.D5L7. 1
B
TCSG.B4L7. 1
TC SG.A4L7 B1
.
TCSG.A 4L7 B1
.
TC SG.B4R7 B1
.B
S
TC G.D5R7 1
SG 5R .B1
TC .E5 7.B
TC SG. R7. 1
6 B
TCLA.A R7. 1
6 B
TC LA.B R7. 1
B
6
L
A
TC .C R7. 1
L 6 B
TC A.D R7. 1
L 6 B
TC A.A R7. 1
T 7 B
TC PH R7.B1
.
TC TPV 4L8. 1
B
.
TCTPH 4L8.B1
TP .4L 1
V.4 1.B
L1 1
.B1
TC
L.
TCTCL.4R1.
TP 5R B1
H. 1.B
TC TDI 4L2. 1
TP .4L B1
V.4 2.B
TC TCL L2.B1
LIB IA. 1
TC .6R 4R2
P
TC .6 2.B
T SG L3 1
TCCSG .5L3.B1
TCSG.A.4R3.B1
.
S
TC G.B5R3.B1
TCLA.A5R3.B1
LA 5R B1
TC .B5 3.B
T L A. R 3 . 1
TCCLA.6R3.B1
B
TCTPH 7R3. 1
TP .4L B1
TC V.4L5.B1
TC TCL.4R5.B1
TCDQA L.5R5.B1
TC DQA.A4R5.B1
DQ .B 6.
TC A.C4R6 B1
S 4 .B
TCP.A4R6.B1
TCP.D6R6.B1
TCP.C6L7.B1
TC P.B L7 1
.
TCSG.A6L7 B1
.
TCSG.B6L7 B1
.
TC SG.A5L7 B1
.
TCSG.D5L7 B1
.
TCSG.B4L7 B1
TC SG. 4L7.B1
A
TCSG.A 4L7.B1
S
4
TC G.B R7.B1
TCSG.D5R7.B1
S 5 .B
TCG.E R7. 1
TC SG 5R7.B1
.
TCLA.A6R7 B1
.
TC LA.B6R7 B1
.
TCLA.C6R7 B1
.
TCLA.D6R7.B1
TCLA.A6R7.B1
B
TCTPH 7R7. 1
.
TC TPV 4L8.B1
.
B
TCTPH 4L8. 1
TP .4L B1
V.4 1.B
L1 1
.B1
B1_V
Beam losses rate on collimators (1/m)
B1_H
Beam losses rate on collimators (1/m)
Beam losses distribution on collimators with three versions of SixTrack
10
The ratio of MSM-SixTrack and Fluka-SixTrack to Standard SixTrack
10
The ratio of MSM-SixTrack to Standard-SixTrack
The ratio of Fluka-SixTrack to Standard-SixTrack
1
0.1
0.01
10
The ratio of MSM-SixTrack to Standard-SixTrack
The ratio of Fluka-SixTrack to Standard-SixTrack
1
0.1
0.01
0.1
0.01
0.001
1E-4
1E-5
1E-6
1E-7
10
1
Standard-SixTrack
MSM-SixTrack
Fluka-SixTrack
0.1
0.01
0.001
1E-4
1E-5
1E-6
1E-7
TC
TC TPV
T .4
TC PH. R1.
4 B
TC TPV R1. 2
TP .4R B2
TC H.4R2.B2
LA 2.
TC .7 B
TC LA. L3.B2
L 6
TC A.B L3.B2
TC LA.A5L3. 2
B
S
TC G.B5L3. 2
SG 5L B2
TC .A5 3.B
2
TC SG.4L3.B
SG L3 2
TC .5R .B2
P 3
TC .6R3.B2
L. .B
TC TCL 5L5. 2
B
.
TC TPV 4L5. 2
TP .4R B2
T H 5
TC CSP .4R .B2
DQ .A4 5.B
TC A L6 2
D .
TC QA C4L6.B2
DQ .B4 .B
TC A.A L6.B2
4
TC LA.A L6.B2
L 7
TC A.D L7.B2
LA 6L 2
TC .C 7.B
L 6
TC A.B L7.B2
L 6L 2
TC A.A 7.B
TC SG 6L7. 2
B
.
TC SG.E6L7. 2
SG 5L B2
TC .D 7.
B
S
TC G.B5L7. 2
B
TC SG.A5L7. 2
B
S
TC G.A 4L7. 2
B
S
4
TC G.B R7. 2
B
S
TC G.D4R7. 2
SG 4R B2
TC .A 7.
B
S
TC G.B5R7. 2
SG 5R B2
TC .A6 7.B
2
R
P
TC .B6 7.B
P R 2
TC .C6 7.B
P R 2
TC .D6 7.B
LIB R7 2
. .B
TC 6L8. 2
L B
TC TDI IA.4 2
TP .4R L8
H. 8.B
TC 4R 2
L.6 8.B
L1 2
.B2
1
Standard-SixTrack
MSM-SixTrack
Fluka-SixTrack
The ratio of beam losses to Standard-SixTrack
Beam losses rate on collimators
The ratio of beam losses to Standard-SixTrack
TC
TC TPV
.
TCTPH 4R1.
.
TC TPV 4R1 B2
TP .4R .B2
TC H.4 2.B
R 2
T LA. 2.B
TCCLA 7L3. 2
.
B
TCLA.B6L3. 2
B
5
L
TC A.A L3. 2
B
TCSG.B5L3. 2
SG 5L B2
3
TC .A5 .B
TC SG. L3.B2
SG 4L 2
TC .5R3.B2
P 3
TC .6R .B2
L. 3.B
TC TCL 5L5. 2
T
TC PV .4L5 B2
TP .4R .B2
T H 5
TC CSP .4R .B2
5
D
TC QA .A4L .B2
. 6
TCDQA C4L .B2
DQ .B4 6.B
TC A.A L6. 2
B
TC LA.A4L6. 2
B
TCLA.D7L7. 2
B
TCLA.C6L7. 2
B
TCLA.B6L7. 2
L 6 B2
T A.A L7.B
TCCSG 6L7. 2
TC SG.E.6L7 B2
.B
TCSG.D5L7. 2
B
TCSG.B5L7. 2
TC SG. 5L7 B2
A .
TCSG.A 4L7 B2
.
TC SG.B4R7 B2
.
TCSG.D4R7 B2
.
TCSG.A4R7 B2
.
TCSG.B5R7 B2
SG 5 .B
TC .A6R7.B2
R
P
TC .B6 7.B2
TCP.C6R7.B2
R
TCP.D6 7.B2
LIB R7 2
.
TC.6L8 B2
.
L
T
I
TC DI A.4B2
TP .4R L8
H. 8.B
TC 4R 2
8
TCL.6L .B2
1
TCL.5L .B2
L.4 1.B
L1 2
.B2
10
TC
TC TPV
.
TCTPH 4R1.
.
TC TPV 4R1 B2
TP .4R .B2
TC H.4 2.B
R 2
T LA. 2.B
TCCLA 7L3. 2
.
B
TCLA.B6L3. 2
B
TC LA.A5L3. 2
B
TCSG.B5L3. 2
SG 5L B2
TC .A5 3.B
TC SG. L3.B2
SG 4L 2
TC .5R3.B2
P 3
TC .6R .B2
L. 3.B
TC TCL 5L5. 2
TC TPV .4L5 B2
TP .4R .B2
T H 5
TC CSP .4R .B2
5
D
TC QA .A4L .B2
. 6
TCDQA C4L .B2
DQ .B4 6.B
L
A
TC .A 6. 2
B
TC LA.A4L6. 2
B
TCLA.D7L7. 2
B
TCLA.C6L7. 2
B2
6
L
L
A
TC .B 7.
L 6 B2
T A.A L7.B
TCCSG 6L7. 2
TC SG.E.6L7 B2
.B
TCSG.D5L7. 2
B
TCSG.B5L7. 2
TC SG. 5L7 B2
A4 .B
S
TC G.A L7 2
.
TC SG.B4R7 B2
.
TCSG.D4R7 B2
.
TCSG.A4R7 B2
.
S
5
TC G.B R7 B2
SG 5 .B
TC .A6R7.B2
TC P.B6R7.B2
TCP.C6R7.B2
TCP.D6R7.B2
LIB R7 2
.
TC.6L8 B2
.
TC TDI LIA.4B2
TP .4R L8
H. 8.B
4
TC R 2
8
L
TC .6L .B2
1
TCL.5L .B2
L.4 1.B
L1 2
.B2
TC
TC TPV
.
TCTPH 4R1.
.
TC TPV 4R1 B2
TP .4R .B2
H
TC .4 2.B
R 2
T LA. 2.B
TCCLA 7L3. 2
. B
TCLA.B6L3. 2
B
TC LA.A5L3. 2
B
TCSG.B5L3 2
S 5 .B2
TCG.A5L3.B
TC SG. L3.B2
SG 4L 2
TC .5R3.B2
P 3
TC .6R .B2
L. 3.B
TC TCL 5L5 2
. .B
T
TC PV 4L5 2
T .4 .B
T PH R5 2
TC CSP .4R .B2
5
D
TC QA .A4L .B2
. 6
TCDQA C4L .B2
DQ .B 6.B
TC A.A4L6. 2
B
TC LA.A4L6. 2
B
TCLA.D7L7. 2
B
TCLA.C6L7. 2
B2
6
L
L
A
TC .B 7.
L 6 B2
TC A.A L7.B
TC SG 6L7. 2
. B
TC SG.E6L7 2
.B
TCSG.D5L7 2
.B
TCSG.B5L7. 2
TC SG. 5L7 B2
A .
TCSG.A 4L7 B2
.
TC SG.B4R7 B2
.
TCSG.D4R7 B2
.
TCSG.A4R7 B2
.
TCSG.B5R7 B2
SG 5R .B
TC .A6 7.B2
R
P
TC .B6 7.B2
TCP.C6R7.B2
R
TCP.D6 7.B2
LIB R7 2
.
TC.6L8 B2
.
L
TC TDI IA.4B2
TP .4R L8
H. 8.B
TC 4R 2
8
TCL.6L .B2
1
TCL.5L .B2
L.4 1.B
L1 2
.B2
B2_V
Beam losses rate on collimators (1/m)
B2_H
Beam losses rate on collimators (1/m)
Beam losses distribution on collimators with three versions of SixTrack
The ratio of MSM-SixTrack and Fluka-SixTrack to Standard-SixTrack
10
The ratio of MSM-SixTrack to Standard-SixTrack
The ratio of Fluka-SixTrack to Standard-SixTrack
1
0.1
10
The ratio of MSM-SixTrack to Standard-SixTrack
The ratio of Fluka-SixTrack to Standard-SixTrack
1
0.1
Average cleaning
inefficiency
B1_H
Standard-SixTrack
Zoom in DS
𝟖. 𝟒 × 𝟏𝟎−𝟔
𝟓. 𝟔 × 𝟏𝟎−𝟔
Zoom in DS
MSM-SixTrack
6.4× 𝟏𝟎−𝟔
3. 𝟐 × 𝟏𝟎−𝟔
Average cleaning
inefficiency
B1_V
Standard-SixTrack
Zoom in DS
𝟕. 𝟒 × 𝟏𝟎−𝟔
𝟓. 𝟗 × 𝟏𝟎−𝟔
Zoom in DS
MSM-SixTrack
𝟓. 𝟔 × 𝟏𝟎−𝟔
𝟑. 𝟔 × 𝟏𝟎−𝟔
Average cleaning
inefficiency
B2_H
Standard-SixTrack
MSM-SixTrack
Zoom in DS
𝟓. 𝟔 × 𝟏𝟎−𝟔
𝟗. 𝟗 × 𝟏𝟎−𝟔
Zoom in DS
7. 𝟔 × 𝟏𝟎−𝟔
𝟑. 𝟏 × 𝟏𝟎−𝟔
Most cold losses
Average cleaning
inefficiency
B2_V
Standard-SixTrack
MSM-SixTrack
Zoom in DS
𝟓. 𝟒 × 𝟏𝟎−𝟔
𝟖. 𝟎 × 𝟏𝟎−𝟔
Zoom in DS
𝟑. 𝟑 × 𝟏𝟎−𝟔
5. 𝟓 × 𝟏𝟎−𝟔
Cold losses comparison in DS region
B1
1E-4
Ratio of MSM-SixTrack to Standard-SixTrack
Ratio of Fluka-SixTrack to Standard-SixTrack
Ratio of MSM-SixTrack to Fluka-SixTrack
Ratio of cleaning inefficiency
Cleaning inefficiency (1/m)
Standard-SixTrack
MSM-SixTrack
Fluka-SixTrack
1E-5
1E-6
1E-7
1
0.1
DS1
DS2
DS3
DS1
B1_H
DS2
DS3
B1_H
1E-4
Ratio of MSM-SixTrack to Standard-SixTrack
Ratio of Fluka-SixTrack to Standard-SixTrack
Ratio of MSM-SixTrack to Fluka-SixTrack
Ratio of cleaning inefficiency
Cleaning inefficiency (1/m)
Standard-SixTrack
MSM-SixTrack
Fluka-SixTrack
1E-5
1E-6
1E-7
1
0.1
DS1
DS2
B1_V
DS3
DS1
DS2
B1_V
 MSM-SixTrack and Fluka-SixTrack have the similar cold losses in DS region
 Both less than Standard-SixTrack (60% to 80%)
DS3
Cold losses in DS region
B2
1E-4
Ratio of MSM-SixTrack to Standard-SixTrack
Ratio of Fluka-SixTrack to Standard-SixTrack
Ratio of MSM-SixTrack to Fluka-SixTrack
Ratio of cleaning inefficiency
Cleaning inefficiency (1/m)
Standard-SixTrack
MSM-SixTrack
Fluka-SixTrack
1E-5
1E-6
1E-7
1
0.1
DS1
DS2
DS3
DS1
B2_H
DS2
DS3
B2_H
1E-4
Ratio of MSM-SixTrack to Standard-SixTrack
Ratio of Fluka-SixTrack to Standard-SixTrack
Ratio of MSM-SixTrack to Fluka-SixTrack
Ratio of cleaning inefficiency
Cleaning inefficiency (1/m)
Standard-SixTrack
MSM-SixTrack
Fluka-SixTrack
1E-5
1E-6
1
0.1
1E-7
DS1
DS2
B2_V
DS3
DS1
DS2
DS3
B2_V
 MSM-SixTrack and Fluka-SixTrack have the similar cold losses in DS region
 Both less than Standard-SixTrack (60% to 80%)
Single-jaw test Configuration
• LHC 2016 configuration
• Simulation codes:
Standard-SixTrack,
MSM-SixTrack
• Single-jaw chosen: TCP. C6L7.B1
• Beam scenery: B1_H
• Jaw aperture: 5.5 σ
• Jaw thickness: 1 cm
• Beam type: pencil beam
• Impact parameter: 1 σ
• 10 M particles
• Single turn
• All plots normalized to 1
Single-jaw
Single jaw test: angle offset
0.020
0.040
- Standard-SixTrack
- MSM-SixTrack
0.018
- Standard-SixTrack
- MSM-SixTrack
0.035
Relative Frequency
Relative Frequency
0.016
0.014
0.012
0.010
0.008
0.006
0.030
0.025
0.020
0.015
0.010
0.004
0.005
0.002
0.000
0.00000
0.00002
0.00004
0.00006
Angle offset due to elastic scattering
0.00008
2
0.00010
2 1/2
(x' +y' )
0.000
0.00000
0.00005
0.00010
Angle offset due to SD scattering
0.00015
2
0.00020
2 1/2
(x' +y' )
energy offset
Relative Frequency
Standard-SixTrack
MSM-SixTrack
Standard-SixTrack
MSM-SixTrack
0.1
0.001
0.0001
0.0003
0.0005
0.0007
0.0009
Energy offset due to Single Diffractive scattering (P-P0)/P0
0.01
Standard-Sixtrack
MSM-Sixtrack
0.1
0.001
1E-4
3E-7
1E-6
1.7E-6
Energy offset due to ionization
2.4E-6
Relative Frequency
Relative Frequency
1
0.01
0.01
0.001
0.00
0.02
0.04
0.06
0.08
0.10
0.12
Energy offset due to Single Diffractive scattering (P-P0)/P0
Conclusions
 Four sceneries (B1_H, B1_V, B2_H, B2_V) have been compared with three versions of SixTrack: StandardSixTrack, MSM-SixTrack, and Fluka-SixTrack
 For the comparison of the three SixTrack versions,
-> Three versions have quite similar beam loss distributions
-> For beam losses on collimators, Fluka-SixTrack has the most losses while MSM-SixTrack has the least
losses
-> Fluka-SixTrack and MSM-SixTrack are more similar with each other in DS region than StandardSixTrack
 For the single-jaw tests,
-> the energy offset due to ionization looks quite different, while the energy offset due to SD looks quite
similar
-> the angle offset due to elastic scattering and SD scattering look very similar
 Thanks to S. Redaelli, R. Bruce, A. Mereghetti, J. Molson, K. Sjobaek, M. Fiascaris for discussing
 Thanks to J. Molson for giving me the help of running MSM-SixTrack
 Thanks to A. Mereghetti for supplying the data of Fluka-SixTrack