CNGS brainstorming

1
CNGS brainstorming

• This is a non exhaustive analysis of various
  scenari of the
• LINACs-PSB-PS-SPS chain in view to increase the
  intensity for CNGS
• taking into account only transfer energies,
  sp.ch. tune shift,
• acceptance limitations
• the newCT (5 turns) is assumed to work perfectly
• for a given acceptance A we consider
  transmissible (1 losses) a beam
• with an emittance of e3s A 9 e1s 9 e2s /4
• e.g. PS Ax 60 mm Ay 20 mm (see HEACC
  1989, p.444)
• results in e x,2s lt 26 mm ey,2slt 9 mm
• (taking into account dispersion effects gt
  e,x,2s lt 22 mm )
• In all scenari 2 PS pulses are injected into
  the SPS
• In all scenari h8gth16gtdeb.-reb.at 200MHz as
  usual
• In all cases (except case 0, i.e. now) I assumed
  almost
• no losses, no b.u.s , no instabilities, etc. gt
• VERY OPTIMISTIC CASES !!

2
CASE 0 to day measured values
L2
50 MeV
Nt 3.3
exlt 22 eylt 9
1.4 GeV, h0.9
DQ x,y 0.13 0.23
ex 23 ey 11
Nt 3
14 GeV/c 5t CT h0.8
NB in all transparencies 1) ex4sx2/bx in
mm 2) intensities Nt are in 1013 p 3) h is the
transfer efficiency 4) yp is the p flux on target
in 1013p/s
X
ex 4.2/3 1.4 ey 2.5
exlt 3 eylt 2
Theoretical values
Nt 4.8
RMKS 20 losses in the PS to SPS transfer
ex 3.3/3 1.1 ey 1.4
filling time 1.2s yp 4.8/6 0.8 G 1
3
CASE 1.1 double batch inj.
L2
NBFrom now on all ideal values (no b.u.)
50 MeV
Nt 2 x 2.4
exlt 22 eylt 9
1.4 GeV h1
ex 21 ey 9.2
DQ x,y 0.21 0.35
Nt 4.8 gt Intensity limit for a PS _at_ 1.4 GeV
14 GeV/c old 5t CT h0.8
exlt 3 eylt 2
ex 3.4/3 1.13 ey 1.4
Nt 7.7
RMKS x 1.6 intensity improvement but longer
filling time
filling time 2.4s yp 7.7/7.2 1.07
G 1.34 yp 7.7/6.6 1.17 if PSB_at_.6s, G 1.46
4
CASE 1.2 dbl batch newCT
L2
50 MeV
Nt 2 x 2.4
exlt 22 eylt 9
1.4 GeV, h0.9
ex 21 ey 9.2
Nt 4.8
14 GeV/c new5t CT h0.9
ex 3.4/5 0.68 ey 1.4
exlt 3 eylt 2
RMKS 10 improvement as h0.9 lower transfer
losses
Nt 8.6
filling time 2.4s yp 8.6/7.2 1.19 G
1.49 yp 8.6/6.6 1.30 if PSB_at_.6s G 1.63
5
CASE 1.3 dbl. batch nCT 26GeV/c
L2
50 MeV
Nt 2 x 2.4
exlt 22 eylt 9
1.4 GeV, h1
ex 21 ey 9.2
Nt 4.8
26 GeV/c new 5t CT h0.9
ex 1.8/5 0.4 ey .8
exlt 3 eylt 2
Nt 8.6
RMKS injecting above SPS transition
filling time 3.6s yp 8.6/8.4 1.02
G 1.28 yp 8.6/7.8 1.10 if PSB_at_.6s G 1.38
6
CASE 2.1 new H- LINAC nCT
L4
120 MeV, H-
Nt 4.8
exlt 22 eylt 9
1.4 GeV
ex 21 ey 9
Nt 4.8
14 GeV/c new 5t CT h0.9
ex 3.36/5 0.67 ey 1.4
exlt 3 eylt 2
RMKS the best up to now
Nt 8.6
filling time 1.2s yp 8.6/6 1.43 G 1.79
7
CASE 2.2 new H- LINAC 3x3tCT
L4
120 MeV, H-
Nt 4.8
exlt 22 eylt 9
1.4 GeV
ex 21 ey 9
Nt 4.8
14 GeV/c 3t CT h0.8
ex 3.36/3 1.1 ey 1.4
exlt 3 eylt 2
Nt 11.5
RMKS good but lossy (1.4E13 p/scycle lost at
extr.)
filling time 2.4s yp 11.5/7.2 1.6 G 2
8
CASE 3 SPL H- nCT
exlt 22 eylt 9
2.2GeV, H-
DQ x,y 0.20 0.34
Nt 12.8
gt Intensity limit for a PS _at_2.2 GeV
14 GeV/c new 5t CT h0.9
exlt 3 eylt 2
ex 4.7/5 1 ey 1.9
Nt 23
RMKS the very best up to now, not as easy,
probably impossible. High losses and coll.
effects e.g.BBU_at_trans.gt0.6/2eVsgt1.6/5eVs
gtnewRF? New PS ? Below transition?..? SPS?
filling time 1.2s yp 23/6 3.8 G 4.79
9
SUMMARY
10
SUMMARY modif. on 27.4.01
11
CONCLUSION

• a factor 1.5 seems feasible though difficult
  (range 5MCHF)
• a factor 2 maybe possible but VERY difficult
  (range 50MCHF)
• a factor 3 is unrealistic even with large amount
  of money
• ( range 400MCHF)
• cases 1.1 (dbl batch ) and 1.2 (new5tCT) are
  good starting points to explore limitations. They
  can be implemented at zero cost.