OPTIMIZEDSOLENOIDBASEDCAPTUREMECHANISMFORA) … · 13/22/13 Hisham)Sayed);)Higgs)factory)UCLA) 9. MOREC OOLING?! 0 2000 4000 6000 8000 10000 12000 0 50 100 150 200 250 300 350 Muon+/proton

OPTIMIZED SOLENOID BASED CAPTURE MECHANISM FOR A MUON COLLIDER/NEUTRINO FACTORY TARGET SYSTEM

HISHAM KAMAL SAYED Physics Department

BROOKHAVEN NATIONAL LABORATORY

HIGGS FACTORY UCLA MARCH 22 2013

LAYOUT

1-‐ Introducing Muon Collider Target & Front END 3-‐ Capture Solenoid Field Study: QuesNons that needs answers

u  What are the target Solenoid parameters that affect the parNcle Capture & Transmission at target or aTer cooling

u  Can/How Capture Solenoid change the quanNty & quality of captured parNcles ?! u  Does the Nme of arrival affect the efficiency of the capturing mechanism? u  Does the proton bunch length influence the muon/proton yield at the end of the cooling channel ?

4-‐ Muon yield at end of decay channel 5-‐ Muon yield at end of cooling channel 6-‐ Taper scan 7-‐ Time of arrival dependence & Nme scan 8-‐ Results of taper & TOA opNmizaNon

Hisham Sayed -‐ Higgs factory UCLA 13/22/13

2

MUON COLLIDER/NEUTRINO FACTORY LAYOUT

Target System Solenoid: Capture µ± of energies ~ 100-‐400 MeV from a 4-‐MW proton beam (E ~ 8 GeV).


3

TARGET SYSTEM CURRENT BASELINE DESIGN

Ø  ProducNon of 1014 µ/s from 1015 p/s (≈ 4 MW proton beam)

Ø  Capturing low energy π's Ø  Solenoid coils can be some distance from proton beam.

Ø  ≥ 10-‐year life against radiaNon damage at 4 MW. Ø  Proton beam readily Nlted with respect to magneNc

axis. Ø  ⇒ Beam dump (mercury pool) out of the way of

secondary π's and µ's. Ø  Shielding of the superconducNng magnets from

radiaNon is a major issue. Ø  Magnet stored energy ~ 3 GJ

SC magnets

ResisNve magnets

Proton beam and Mercury jet

Tungsten beads

Mercury collecNon pool With splash miNgator

5-‐T copper magnet insert; 10-‐T Nb3Sn coil + 5-‐T NbTi outsert. Desirable to eliminate the copper magnet (or replace by a 20-‐T HTS insert).

Ø Hg Target Ø  θTarget=0.137 rad Ø  RTarget=0.404 cm

Ø Proton Beam Ø  E=8 GeV Ø  θBeam=0.117 rad Ø  σx=σy=0.1212 cm (Gaussian DistribuNon)

Ø Solenoid Field Ø  IDS120h à 20 T peak field at target posiNon (Z=-‐37.5) Ø  Aperture at Target R=7.5 cm -‐ End aperture R = 30 cm Ø  Fixed Field Z = 15 m à Bz=1.5 T

Ø ProducNon: Muons within energy KE cut 40-‐180 MeV end of decay channel

Ø  Nμ+π+κ/NP=0.3-‐0.4 Hisham Sayed -‐ Higgs factory UCLA 13/22/13

4

TAPERED TARGET SOLENOID

0

5

10

15

20

0 5 10 15 20 25 30 35

Bz

[T]

z [m]

Ltaper= 5 [m]Ltaper=15 [m]Ltaper=25 [m]Ltaper=35 [m]

0

5

10

15

20

0 5 10 15 20 25 30 35

Bz

[T]

z [m]


0

5

10

15

20

0 5 10 15 20 25 30 35

Bz

[T]

z [m]


0

5

10

15

20

0 5 10 15 20 25 30 35

Bz

[T]

z [m]


0

5

10

15

20

0 5 10 15 20 25 30 35

Bz

[T]

z [m]


0

5

10

15

20

0 5 10 15 20 25 30 35

Bz

[T]

z [m]


0 5

10 15

20 25

30 35 0

0.05 0.1

0.15 0.2

0.25 0.3

0.35 0.4

0.45 0.5

0 2 4 6 8

10 12 14 16 18 20

Bz(

z,R

) [T

]

z [m]

R [m]

Bz(

z,R

) [T

]

Inverse-‐Cubic Taper Bz (0, zi < z < z f ) =

B1[1+ a1(z− z1)+ a2 (z− z1)

2 + a3(z− z1)3]p

a1= − B1'

pB1a2 = 3

(B1 / B2 )1/p −1

(z2 − z1)2 −

2a1z2 − z1

a3 = −2(B1 / B2 )

1/p −1(z2 − z1)

3 +a1

(z2 − z1)2

Bz (r, z) = (−1)nn∑ a0

(2n) (z)(n!)2

( r2)2n

Off-‐axis field approximaNon Br (r, z) = (−1)n+1n∑ a0

(2n+1)(z)(n+1)(n!)2

( r2)2n+1

a0(n) =

dna0dzn

=dnBz (0, z)

dzn

1.5 T 2.5 T 3.5 T

1.5 T 2.5 T 3.5 T

5

MARS SIMULATIONS & TRANSMISSION

0

0.1

0.2

0.3

0.4

0.5

0.6

0 50 100 150 200 250 300

N [

Muon

s]

Z [m]

Ltaper= 4.00 m n1Ltaper= 12.00 m n1Ltaper= 24.00 m n1Ltaper= 40.00 m n1Ltaper= 4.00 m n0

Ltaper= 12.00 m n0Ltaper= 24.00 m n0Ltaper= 40.00 m n0

Ltaper= 4.00 m NLtaper= 12.00 m NLtaper= 24.00 m NLtaper= 40.00 m N

Nmuons{Good}

Nmuons{Pz cut}

Nmuons{All cuts}

Good parNcles condiNons/cuts Ø  Survived the buncher-‐phase rotator and cooling

secNons Ø  AcceleraNon acceptance cuts

Ø  0.1 <Pz< 0.3 GeV Ø  Transverse cut R < 0.03 m Ø  Longitudinal cut < 0.015 m

0.35

0.36

0.37

0.38

0.39

0.4

0.41

0.42

500 1000 1500 2000 2500 3000 3500 4000 4500

N[m

uons

]/N[p

]

Zend [m]

Bz=20 -> 1.5 T15 -> 1.5 T

15 -> 1.66 T15 -> 1.8 T

MARS simulaNon results CounNng muons at 50 m with K.E. 80-‐140 MeV MARS-‐ICOOL simulaNon results

CounNng muons at various z

Ltaper [cm]

rfinal=30 cm

Rini=7.5-‐10 cm

Bi=20-‐15 T


6

PHASE SPACE DISTRIBUTIONS (SHORT VERSUS LONG TAPER)

0

0.0005

0.001

0.0015

0.002

0.0025

0.003

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45

Meson/Proton

R [m]

Bz=20-1.5 z=50

Ltaper=4.00Ltaper=40.00

0

0.001

0.002

0.003

0.004

0.005

0.006

0.007

0 0.5 1 1.5 2 2.5 3

Meson/Proton

Pz [GeV/c]

Bz=20-1.5 z=50 m

Ltaper=4.00 Ltaper=40.00

0

0.001

0.002

0.003

0.004

0.005

0.006

0.007

0.008

0.009

0 0.05 0.1 0.15 0.2 0.25

Meson/Proton

Pt [GeV/c]

Bz=20-1.5 z=50


0

0.0005

0.001

0.0015

0.002

0.0025

0.003

0.0035

0.004

0 1 2 3 4 5 6 7

Meson/Proton

Ptotal [GeV/c]

Bz=20-1.5 z=50 m


π Good μ

All μ

Good μ

All μ

Good μ

All μ

Good μ

All μ

No difference between short & long solenoid taper produced parNcles Hisham Sayed -‐ Higgs factory UCLA 13/22/13

7

PHASE SPACE DISTRIBUTIONS (SHORT VERSUS LONG TAPER)

0

0.2

0.4

0.6

0.8

1

160 180 200 220 240 260 280 300

Pz [GeV/c]

T [nsec]

Bz=20-1.5 z=50 m

Ltaper=4.00 GoodLtaper=40.00 Good

Short T

aper

Long Taper

Short Taper

Long Taper

T-‐Pz CorrelaNons at end of decay channel

Good ParNcles

Long Solenoid taper: Ø  More parNcles Ø  More dispersed (misses the buncher

acceptance windows) Short Solenoid taper: more condensed distribuNons that fits more parNcles within the acceptance window)


8

PERFORMANCE DEPENDENCE ON TIME OF ARRIVAL

0

0.02

0.04

0.06

0.08

0.1

0.12

0 50 100 150 200 250 300

Muon+/proton

Z [m]

Bz=15-1.5T Ltaper= 5.000

DTOA=2.044e-09 DTOA=4.044e-09 DTOA=6.544e-09

DTOA=1.1544e-08

0

0.02

0.04

0.06

0.08

0.1

0.12

0 50 100 150 200 250 300

Muon+/proton

Z [m]

Bz=20-1.5T Ltaper= 5.000

DTOA=2.044e-09 DTOA=4.044e-09 DTOA=6.544e-09

DTOA=1.1544e-08

0

200

400

600

800

1000

1200

1400

1600

1800

0 2 4 6 8 10

Meson/Proton

Time [nsec]

t=2.044e-09 sect=2.544e-09 sect=3.044e-09 sect=3.544e-09 sect=4.044e-09 sec

t=4.544e-09 sec -BSLINEt=5.044e-09 sect=5.544e-09 sect=6.044e-09 sect=6.544e-09 sec

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

-5 0 5 10 15

MARS1015 2012OLDOLD

TOA Proton

s at z=-‐200 cm

TOA Proton

s at z=-‐75 cm


9

MORE COOLING ?!

0

2000

4000

6000

8000

10000

12000

0 50 100 150 200 250 300 350

Muon+/proton

z [m]

Ltaper vs. n1 B=20-1.5T

TOA=8.80321e-10 Ltaper=2.00TOA=3.80343e-10 Ltaper=4.00TOA=8.80321e-10 Ltaper=6.00TOA=8.80321e-10 Ltaper=8.00

TOA=8.80321e-10 Ltaper=12.00TOA=8.80321e-10 Ltaper=20.00

0

2000

4000

6000

8000

10000

12000

0 50 100 150 200 250 300 350Muon+/proton

z [m]

TOA vs. End n1 Ltaper=8 m B=20-1.5T

TOA=5.38012e-09TOA=4.88014e-09TOA=3.88019e-09TOA=2.88023e-09TOA=1.88028e-09TOA=1.3803e-09

TOA=8.80321e-10TOA=3.80343e-10

TOA=-6.19613e-10TOA=-1.61957e-09TOA=-2.11955e-09TOA=-3.1195e-09

TOA=-4.11946e-09

Baseline cooling end 140 cell (z=265 m)

For every taper length opNmized TOA For 8 m taper length TOA scan


10

TIME & TAPER LENGTH SCAN

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

0.11

0.12

0 5 10 15 20 25 30 35 40

Muon+/proton

Taper Length [m]

Max n1 voer z

Bz=20->1.5TBz=15->1.5TBz=15->2.0TBz=15->2.5T

0.08

0.085

0.09

0.095

0.1

0.105

0.11

0.115

0.12

0.125

0 5 10 15 20 25 30 35 40

Muon+/proton

z [m]

Ltaper vs. n1

B=20-1.5TB=15-1.5TB=15-2.0TB=15-2.5T

Using baseline cooling secNon (140 cooling cell)

Using longer cooling secNon (200 Cooling cell)


11

TIME & TAPER LENGTH SCAN

-5

-4

-3

-2

-1

0

1

2

0 5 10 15 20 25 30 35 40

Time of Arrival [nsec]

Target Solenoid Taper Length [m]

B=20-1.5TB=15-1.5TB=15-2.0TB=15-2.5T

TOA for opNmum throughput at end of cooling for each capture solenoid case


12

OPTIMIZED MUON PRODUCTION AT END OF FRONTEND (BPEAK=20-‐15 T)

0.04

0.06

0.08

0.1

0.12

0.14

0 2 4 6 8 10

Nmoun/Nproton

Taper Length [m]

Pancake Proton Beam Bzi=20 T

Bz=20-1.5TBz=20-2.0TBz=20-2.5TBz=20-3.5T

Baseline


13

>%20

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0 2 4 6 8 10

Nmoun/Nproton

Taper Length [m]

Pancake Proton Beam Bzi=15 T

Bz=15-1.5TBz=15-2.0TBz=15-2.5TBz=15-3.5T

MUON YIELD VERSUS END FIELD & BUNCH LENGTH

0.11

0.115

0.12

0.125

0.13

0.135

0.14

0 0.5 1 1.5 2 2.5 3 3.5 4

Nmoun/Nproton

Bunch Length [nsec]

Production - Proton Bunch Length

Bi=15 T

Bi=20 T

Bunch length=0 nsec

0.11

0.115

0.12

0.125

0.13

0.135

0.14

1 1.5 2 2.5 3 3.5 4

Nmoun/Nproton

B end [T]

Production -Final Solenoid Field

Bi=15TBi=20T

Muon yield versus end field Muon yield versus Proton Bunch Length

Losses at B=3.5T might be due to match to the cooling secNon

2.5% loss per 1 nsec increase in bunch length

Baseline Baseline

20% increase

5% 10%


14

1-‐ Target Solenoid parameters that affect the parNcle Capture & Transmission at target or aTer cooling IniNal peak Field – Taper length – End Field 2-‐ Can Capture Solenoid change the quanNty & quality of captured parNcles ?! yes & yes a-‐ QuanNty: More muons captured with adiabaNc long taper than short taper. b-‐ Quality: Produce be�er quality muons that can be captured efficiently in the buncher-‐phase rotaNon secNons. 3-‐ How the capture solenoid field parameters influence the muon yield a-‐ Peak field (changes quanNty) b-‐ Taper length (quality) c-‐ Final constant end field (quanNty) 4-‐ Does the Nme of arrival affect the efficiency of the capturing mechanism? Yes. Needs to be included in the opNmizaNn of the FE 5-‐ Does the proton bunch length influence the muon/proton yield at the end of the cooling channel ? How? Yes, %2.5 reducNon per 1 nsec increase in bunch length.

CONCLUSION & SUMMARY


15

CONCLUSION & SUMMARY

Ø  The maximum yield requires taper length of 4-‐5 m for all cases (20-‐15T)

(1.5-‐3.5T) for any bunch length.

Ø  Longer cooling channel is required to reach maximum cooling.

Ø  Higher end field à more muon yield

Ø  Longer bunch à Less yield we loos about 2.5% per 1 nsec increase in bunch

length.


16

Documents

OPTIMIZEDSOLENOIDBASEDCAPTUREMECHANISMFORA) … · 13/22/13 Hisham)Sayed);)Higgs)factory)UCLA) 9. MOREC OOLING?! 0 2000 4000 6000 8000 10000 12000 0 50 100 150 200 250 300 350 Muon+/proton