CNGS proton beam. Malika Meddahi for SL/BT group CERN

Transcription

1 CNGS proton beam Malika Meddahi for SL/BT group CERN

2 CNGS proton beam Layout of the proton line Beam parameters Extraction channel New magnets Intensity limitations Requirements for beam instrumentation CNGS proton beam 2

3 CNGS proton beam 3

4 Transfer line layout CNGS proton beam 4

5 Transfer line layout : branching Off CNGS proton beam 5

6 Transfer line layout : half cell CNGS proton beam 6

7 Last 200 m CNGS proton beam 7

8 Beam parameters Beam parameters Nominal energy Normalized emittance Emittance CNGS beam 400 GeV 12 m m # of extractions per cycle 2 separated by 50 ms # of train per extraction 1 # of bunches per train 2090 Intensity per extraction Bunch length (4s) r.m.s. bunch length Bunch spacing Train length p 2 ns 15 cm 5 ns 10.5 s CNGS proton beam 8

9 Optics at target Flexibility of the optics β* at the focus (h/v) minimum beam size/maximum divergence 20 m to 2.5 m 0.27 mm, 0.1 mrad p/p 0.12 % CNGS proton beam 9

10 The Beam Envelope CNGS proton beam 10

11 Dispersion CNGS proton beam 11

12 Trajectory correction scheme Usual trajectory optimization criteria plus cost and space constraints Optimized scheme two possible trajectory corrections: Mode Peaks of 3 s orbit (mm) 1-to-1 X: Y: Overconstrained Y: 2 peaks X: 1 3 s exit angle (mrad) X: 0.05 Y: X: 0.05 Y: Monitor/Correct or counts X: 10 / 10 Y: 10 / 10 X: 10 / 7 Y: 10 / 8 Analysis includes injection, alignment, field errors and monitor offsets. Y. Chao Orbit and angle errors correspond to the values at 3 of the orbit error distribution CNGS proton beam 12

13 SPS extraction Kickers Bumper 1 Bumper 2 Septa Bumper 3 Bumper 4 CNGS proton beam 13

14 Trajectories into the extraction channel B. Goddard SL/BT CNGS proton beam 14

15 MKE Kickers m HVvalues: 52.2, 52.2, 52.2, 52.2, 52.2 kv Deflection from MKE's at TPSE: 45.9 mm Positionat entrance TPSE: 83.3 mm h orizontal p ositio n sigma injected and storedcngsbeam, together with8.2 s physical limit at injection longitudinal position@md Jan Uythoven, SL BT, August 2000 CNGS proton beam 15

16 MKE kicker parameters, LSS4 SPS extraction Mode proton energy Rise time Flat top Fall time Flat top ripple [GeV/c] [µs] [µs] [µs] CNGS protons 400 < <1.1 <2 % Jan Uythoven, SL/BT August 2000 CNGS proton beam 16

17 Transfer line : transport of primary protons Compact magnets, re-use existing power supplies MBG 73 magnets Gap height 37 mm Nominal field : GeV QTG Magnetic length : 6.3 m 21 magnets Magnetic aperture : 45 mm Nominal gradient 40 T/m, 2.2 m long K. Schirm T. Zickler CNGS proton beam 17

18 MBG cross section K. Schirm SL/MS 08/2000 CNGS proton beam 18

19 MBG 2D field profile (OPERA2D; Θ=0.985) 2.00E E E+00 B = 1.699T M B G 70 DB/B -1.00E E E E E-04 x [m m ] K. Schirm SL/MS 08/2000 CNGS proton beam 19

20 QTG Pole Shape (1/8) T. Zickler SL/MS 08/2000 CNGS proton beam 20

21 QTG Gradient Homogeneity QTNF Requested G [T/m] I[A] G[T/m] D G/Gmax D G/G at 21mm Gdl [Tm/m] Bmax [T] 400GeV GeV Homogeneity of G [per mille] x [mm] 400 GeV 450GeV T. Zickler SL/MS 08/2000 CNGS proton beam 21

22 Increasing the intensity Increasing total number of protons per year onto the target 2 ways to increase the SPS intensity : a) increase number of injection from CPS into SPS (2 3) b) increase intensity per injection from CPS. b) is preferred (20 % less intensity than with a) but shorter cycle, and much easier operation). CNGS proton beam 22

23 ACHIEVED CPS p SPS p ULTIMATE CPS > p SPS p CPS side : SPS side : Booster injection energy into CPS : 1 to 1.4 GeV Reduced CPS h into SPS Equalize 4 booster ring intensities Electrostatic septum upgrade/replacement Hardware limitation solved by LHC upgrade program (RF system, damper system, impedance budget) Heating of the ferrite of the kicker system CNGS proton beam 23

24 Mesure : Requirements for Instrumentation Proton beam intensity to 1 % Proton beam position with an accuracy of 0.1 mm and beam angle with 0.1 mrad Beam loss monitors Right upstream of the target : intensity, positions, profiles Beam position and angle at target cycle to cycle CNGS proton beam 24

25 BLM Profiles Profiles Profiles BCT CNGS proton beam 25

26 Profiles BLM BLM Last 200 m Profiles Profiles Position Intensity Profiles BLM BLM CNGS proton beam 26

27 STATUS Layout and concept of primary proton line vacuum magnet design extraction channel instrumentation... CNGS proton beam 27