Activities for CNGS Concerning the OPERA

Results

Gianluigi Arduini, Thomas Bohl, Karel Cornelis, Ilias Efthymiopoulos, Edda Gschwendtner, Mike Lamont, Roberto Losito, Javier Serrano, Rende Steerenberg

b) LHC Beam to CNGS

a) Time Structure of CNGS Muon Spill

CNGS Secondary Beam Working Group(EN-MEF, EN-STI, EN-CV, EN-EL, BE-CO, BE-OP, DGS-RP,

OPERA and ICARUS members)

a) Motivation

horns muon detectors

muons

Any effect on protons/neutrinos in the secondary beam line should be seen in the muon signals

Edda Gschwendtner, CERN

targetmagnetichorns

decay tunnel

hadron absorber

muon detector 1

muon detector 2

SPG/OePG 2009 Edda Gschwendtner, CERN 4

60cm270cm

11.25cm

• 2 x 41 fixed monitors (Ionization Chambers)

• 2 x 1 movable monitor

LHC type Beam Loss Monitors• Stainless steel cylinder • Al electrodes, 0.5cm separation• N2 gas filling

CNGS

Muon Monitors

5

Muon Monitors: Expected Signals

pit 1 Horizontal

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simulation

Horizontal Profile Pit 1pit 2 Horizontal

0

0.002

0.004

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-157.5 -135 -112.5 -90 -67.5 -45 -22.5 0 22.5 45 67.5 90 112.5 135 157.5cm

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Horizontal Profile Pit 2MeasurementsSimulations

P. S

ala

et a

l, FL

UKA

sim

ulati

ons

2008

~5 107 muons/cm2/10.5ms 8 105

muons/cm2/10.5ms

Challenges:

Pit 1: ~1 THz/cm2

Pit 2: ~10-100 GHz/cm2

Different energy spectra in muon profiles in pit 1 and pit 2Background signals smearing the timing signals

Detector choice

Simulations

Diamond DetectorsDetector (very fast!) +electronics system exists in a form that perfectly fits into the general accelerator data taking and logging system.– LHC experiments: Beam condition monitoring– LHC: e.g.: Beam loss monitoring before global LHC abort trigger

6

20 ns / div10 mV / div

SPS SignalIP7

Diamond Detectors for CNGS

7

4-5 x

Combine different diamonds and amplifiers: eg. Single-crystal or Poly-crystal with 2GHz/40dB I-amp

Use kicker extraction signal to trigger the scope (like done for BCFT)Measure the time structure of muon spills with ~1GS/s

Perform cable delay measurements

Planning• Installation during Technical Stop 7-11 Nov 2011

– Tight schedule! (cabling, Ethernet, detector installation,…)

8

LHC schedule

Injector schedule

• Measurements during last days of CNGS run until 21 Nov

LHC beam to CNGS 9

b) Motivation

7-10-2011

LHC beam to CNGS 10

Motivation

7-10-2011

versus

LHC beam to CNGS 11

Reminder – at present• 2*10.5 microseconds extractions from SPS

separated by 50 ms– ~1.8e13 per extraction– ~3.6e13 per cycle– Cycle length 6 s

7-10-2011

4e10

25 ns bins

LHC beam to CNGS 12

CNGS flat-out

7-10-2011

LHC beam to CNGS 13

CNGS & LHC

7-10-2011

LHC pilot

LHC 50 ns

LHC beam to CNGS 14

Duty cycle

• 30/45 of SPS time for CNGS in full production mode but:– LHC filling– Operational inefficiency

• Assumed delivery 2.1e17 pot/day– Corresponds to 9.8 hrs of CNGS cycles only

35.3 nu-events/day

7-10-2011

LHC beam to CNGS 15

Event rate

• 16,111 muon neutrino interactions recorded in 3 years with around 1020 pot– External and internal events

• ~1 event per 6 x 1015 pot• (1 tau event so far)

7-10-2011

LHC beam to CNGS 16

1) 4*single bunch

7-10-2011

• High bunch intensity• Higher neutrino event rate per bunch • Very clearly time delimited – easy to resolve bunch structure• Low overall production rate

Bunch intensity 2.5e11

Bunch spacing 500 ns

0.8 nu-events/day0.2 nu-events/bunch/day

LHC beam to CNGS 17

7*single bunch• An alternative scheme, using H21 at injection in the PS, could be

envisaged after some extra cabling in the RF hardware. We could the have 1, 3, or 7 bunches.

• 7 bunches could be done using a double batch injection from the PSB into the PS (4 + 3), requiring some local cabling.

• In this scheme we need nevertheless to verify if coupled bunch oscillations will be an issue and it will take a bit more time to set up (few days) in the PS.

• Not clear yet how tightly spaced high intensity bunches behave in SPS. Until now only 2 high intensity bunches with large spacing of 1.2us. must be tested.

• --> 7 x 2.5E11 per 7.2 sec.

7-10-2011

Heiko DamerauRende SteerenbergThomas Bohl

1.4 nu-events/day0.2 nu-events/bunch/day

LHC beam to CNGS 18

2) 50 ns

7-10-2011

Bunch intensity 1.5 e11

Bunch spacing 50 ns

Bunches/cycle 144

• Higher number of bunches, Higher overall production rate• Lower neutrino rate per bunch compared with single bunch• Probably beyond limit of OPERA’s ability to resolve bunch structure

5.9 nu-events/day0.04 nu-events/bunch/day

LHC beam to CNGS 19

3) 150 ns

7-10-2011

Bunch intensity 1.2 e11

Bunch spacing 150 ns

Bunches/cycle 48

• Less bunches, shorter cycle wrt 50 ns• Low neutrino rate per bunch • Easy to resolve bunch structure – aim of the exercise

1.9 nu-events/day0.04 nu-events/bunch/day

LHC beam to CNGS 20

4) Hybrid

7-10-2011

• Unambiguous bunch structure• Partially compensates loss in pot

3.9 nu-events/day0.2 nu-event/bunch/day

LHC beam to CNGS 21

Numbers

7-10-2011

Karel Cornelis

LHC beam to CNGS 22

Production per day

7-10-2011

BunchIntensity

bunches per batch

batchesper cycle

cycle length

protons percycle

total nocycles

pot per day

eventsper day

events/bunch/day

single 2.5E+11 4 1 7.2 1.00E+12 4900 4.9E+15 0.8 0.20

single 2.5E+11 7 1 7.2 1.75E+12 4900 8.58E+15 1.4 0.20

50 ns 1.5E+11 36 4 21.6 2.16E+13 1633 3.53E+16 5.9 0.04

150 ns 1.2E+11 12 4 18 5.76E+12 1960 1.13E+16 1.9 0.04

HYBRID 1.5E+11 4+36 1+2 18 1.18E+13 1960 2.31E+16 3.9 0.20

Now 6 3.60E+13 5880 2.12E+17 35.3

LHC beam to CNGS 23

Commissioning

• 2 days off-line preparation• PS have to dig out 150 ns• 2 days commissioning time with beam to checkout:– Interlocks– RF– Re-steer line, check matching, check beam

instrumentation• 7 single bunches, if feasible, would take some time

7-10-2011

LHC beam to CNGS 24

Beam Instrumentation

7-10-2011

TT41 BPM system can deal with LHC type beams.There is a choice of integration gate of 8us (used for regular CNGS operation) and 400ns (used for initial CNGS commissioning). The start of the gate is delayed in both cases by 1us from the autotrigger generated by the first bunch down the line. Hence in order to measure using this system you will need a train of bunches which is longer than 1.5us in duration. The system should, in principle, be able to handle any LHC style structure (25ns->150ns). The minimum intensity per bunch which still gives a measurable signal still needs to be verified.

Thierry BogeyRhodri Jones

LHC beam to CNGS 25

Target

7-10-2011

CNGS LHC

Normalized emittance [micron]

~10 ~1.6 (50 ns)After blow-up >3.0

(more radical blow-up possible)Beam size ratio 0.4

After blow-up >0.55Bunch intensity ~1e10 ~2.5e11

Bunch length [ns] 2 1.5

Target good for 3.5e13 in 10 microseconds, equally distributed

LHC beam to CNGS 26

Target• 4 x 2.5 10^11 is probably acceptable, but I would suggest to

take the time to have at least preliminary simulations of the stresses in the first 3 or 4 graphite rods to verify the margin that we have on paper.

• If we break this target, very probably we shall have to exchange the target station with the spare one, which would have a major impact on the schedule of the facility.

7-10-2011

Roberto Losito

LHC beam to CNGS 27

Issues• Extraction kicker heating with bunched beams• Satellites/ghosts– Single – clean– 150 ns – trickier

• Beam Quality Monitor– Needed? Compatibility with LHC?

• Does the beam hit the target cleanly?• Proton beam exit window, He-tank Ti window– In HiRadMat proton exit window: > 0.5mm

• OTR as BCT cross-check?

7-10-2011

LHC beam to CNGS 28

Issues

• Removing the 50 ns jitter induced by the free-running 20 MHz clock signal in OPERA could help in achieving results faster

7-10-2011

LHC beam to CNGS 29

Draft schedule 2012

7-10-2011