MICE CM18 RAL Alain Blondel 14 June 2007 1 MICE run plan -- steps I and II 1.Establishing the...

1MICE CM18 RAL Alain Blondel 14 June 2007

MICE run plan -- steps I and II

1.Establishing the detailed run plan will be one of the mission of the MICE installation commissionning and operations group (MICO).

2. ’the running strategy will evolve as problems arise;’

3. This has been modified to take into account solenoid issue

Refer to presentations at analysis/CM meetings (AB CRogers 5 August 2005, CM13 October 2005, CM16, analysis december 2006)+ discussions with KTilley and Dieter Renker from PSI.


- STEP I:

April 2007

STEP II: October 2007

STEP III: 2008

STEP IV: 2008

STEP V2008?

STEP VI 2009?2009?

PHASE I

PHASE II

MICE steps as of october 2005


We should revisit our MICE Schedule: as of june 2007 (unchanged since march 2006)

1 October 2007Or january 2008

STEP I

April 2008

STEP III: July 2008

STEP II

STEP IV: Delivery of 1st FCMay 2009

STEP V: summer 2009

STEP VI end 2009

PHASE I

PHASE II

R&D

beam line commissionning starts august 2007(?)

UK PHASE I


Establish beam match andwhether we have all knobs necessary to draw emittance vs. transmission curve. Measure emittance

-- STEPI:

If step I starts feb 1st 2008 and solenoid arrives mid March we have 1.5 monthto get beam and detectors running properly. We estimated that 20 days of beamwere needed. This leaves very little time for installation and commissioning of detectors..

Operation will be interrupted when SS1 arrives until tracker and TOF/KL are installed

Is TOFII needed for step I, II? (in principle trigger on TOF0+TOF1 should suffice).My answer would be NO (no need for downstream trigger either)

It will definitely be needed for step III.

STEP I

STEP II

STEP II -- OK


MICE control room

MICE in February 2008 develop beam with P(B1)=P(B2), align, check rates And target dip, first tries at P(B1)≠P(B2)

Detectors will be installed and running when we start the beam


MICE control room

MICE in May 2008

measurement of emittance and diffuser operation. Develop beam PID, Fill the matrix.


MICE control room

MICE in October-december 2007 Version IVery conservative. Will work. Danger: delays in installing detectors, DAQ, CR, controls etc…

RA12

Target or no target?

Beam passage is plugged


MICE control room

MICE sometimes in (october to december) 2007 version IIAdvantage is obvious. Duration may be limited to a month (november?) Question: can this be achieved (or: what needs to be done to achieve this) without compromizing the Christmas shutdown effort?

TargetIs the present target good enough?

In negative mode, a beam of e- and pi-

How long and which conditions does it take to move B2 in and out?


! the most important point:

•the beam line elements (quads, dipoles) should be well aligned both in position and angles.

•The magnet current to field should be measured (or have been measured) and polarity verified.

Mistakes there take a long time to understand and fix in the tuning process while the preventive actions are straightforward.

The phase advance in the decay solenoid is a free knob and would allow a mini(or maxi)-mization of the outgoing pion beam to facilitate collimation

A collimator downstream of B2 seems absolutely needed to protect the TOF0/Cherenkov and MICE itself from spray induced by the primary momentum particles

Running-in would better be done with a setting where P (B1) = P (B2)

Excerpts of a meeting with Dieter Renker (PSI)


concerning the possibility to have a diagnostic device at the focus behind B1

-- it looks like a good idea except that the beam dispersion is very large and only the on-momentum particles will be focused properly.

Excerpts of a meeting with Dieter Renker (PSI)

--The beam will look like a butterfly or an horizontal hourglass with the focus nominally at the center, but vertical beam size rapidly increasing as one goes on the side horizontally in both directions. If the x-y beam profile monitor is too wide we will integrate over off momentum particle and the sensitivity to the focus may not be great. Also it will be very difficult to locate the horizontal position of the focus. These things should be checked by simulation before we place too much hope in these scifi counters.

--According to the turtle file there is vacuum between the target and the exit of B2. This would cause a problem when trying to place a detector just after B1 (NB discussing with Paul afterwards there will be a small vacuum break there between B1 and decay solenoid in any case but it may require modification to fit a detector)


beam aligned? question 1: how well should the <x> <x’> and <y> <y’> be =0 for beam to be considered aligned? answer (Chris Rogers) : assume we want to reweight the beam with factor per particle of no more than 10% leads to alignment of better than xx ~ 1 mm and similarly in the other dimensions. Reweighting factors increase very rapidly with mismatch.

this will require about ~1000 muons (a few seconds) for one dimension For 5 dimensions will need up to 250 points (35)depending on correlation of parameters(30 if x and y are not correlated)-- easy. – if one has the knobs to do the tune!

Correctors will be absolutely needed for x, x’ y, y’ . 4 knobs at leastHow do we correct dispersion?


-- We will also need data to do the initial alignment/calibration/characterization of the detectors. Without and with mag field, vs momentum etc…

I think the detector experts should think about it and define their needs.

-- muon beam with small momentum spread? would be very useful in step I – need will be obsolete when we have SS1

-- beam enhanced in electrons or pions in order to tune up the PID detectors

-- We will also need to establish the beam momentum scale … (wrt TOF?)

Ancillary data and measurements


STEPI

1. running in of the beam line. This assumes that all magnet polarities and fields have been tested by powering during the shut down

2. it is suggested to run-in with negative polarity and P(B1)=P(B2)only electrons and negative pions/mus to simplify pile-up in TOF0)

3. it is assumed that tracker TOF0 and TOF1 are complete, x y x’ y’ are availale

4. Beam momentum spread?

target running in ?6? shifts

verify leaks, dip, radiation etc….

first beam from target to bend 1 to decay solenoid ?6? shiftsthrough DK solenoid and to Bend 2

need a fluo screen with videocam or a transportable and operational TOF0 or… no quads powered at first go.


measurements at TOF06 shifts

will allow first meast of through rate (negatives first) as fn of B1, B2max should be B1=B2

TOF0, TOF1 negatives and B1=B2 to keep electrons and low dipping target3 shifts

will allow verification of TOF time calibration and verification of beam alignment on TOFs. positions of TOFs set up cherenkov

scan beam dipoles for alignment and quadrupoles for misalignment20 shifts

findout if quad is misaligned by checking change of av. position vs change of currentnote qads misalignments for future realignment

obtain aligned beam with B1=B2 after 41 shifts = 14 days.


vary B1 and B2 at the same time to verify momentum relation(1 shift)

calibrate using TOF0-TOF1 on pions w.r.t. electrons

begin to explore B2.ne.B16 shifts

electrons should become rare and muon peak appear.

redo alignment with B2=0.6 B12 shifts

obtain an aligned muon beam first measurement of beam size in TOF1

vary optics10 shifts

to verify that the beam sizes are approximately correct

total estimated beam time requested for stepI: 60 shifts = 20 days.


Step II: Detector commissioning

Goals:Commission detector systems:

Tracker and solenoidAlignment, calibration

Magnet offPencil beam what is the requirement here?

Demonstrate beams for MICE:Alignment of beam(Lack of) dispersionRange of transverse emittancesRange of momenta

Demonstrate match into MICE spectrometer

Range of transverse emittancesRange of momenta

STEP I:

STEP II:

STEP III:

STEP IV:

STEP V

-

STEP VI

STEP I:

STEP II:

STEP III:

STEP IV:

STEP V

--

STEP VI

2 weeks total1 week

I dont understand the need for the pencil beam … we measure momentum particle by particle twice (TOF+tracker) already

here it will be critical to have the knobs to tune this

how do we correct for dispersion?quads and diffuserB1 B2 another three weeks

total STEPII 7 weeks = 50 days


This is very preliminary and should be looked at by others. It looks as if the running in of MICE stepI and II will require

about 70 days of beam time

Need to have run periods separated by periods for Thinking Fix thingsAnalyse results

This thus can be estimated to last ~6 months not including installation time

20 january to mid-june (arrival of SS2) = 4 months.

I believe that ~2 months would be missing if we start to install detectors after the Xmas shut down.


beam matched? we will want to generate matched beam: x

2 = x’

2 =

with no dispersion. but perhaps a particular relation between amplitude and energy question 2: what precision is needed on this match to satisfy cooling measurements? question 3: can the beam gnerate the energy-amplitude relation or should the analysis do it?

beam intensity? Obtaining the ‘right’ number of muons per spill at 140 MeV/c or 240 MeV/c will require different tuning of the target dip depth -- or collimation. Which is more desirable? many knobs to scan for a given diffuser setting. what precision needed how many muons will be needed to do this?

Once the baseline setting is matched and understood, will want to repeat theexercize for various momenta and various diffuser to check that we can really generate all beams we need/want from 1 to 10 mm emittance.


Bob Palmer:

in MICE, the diffuser does not generate this kind of correlations, and we may want to scan momentum to ensure good populationof phase space in the corners.

p-

p0

p+

MICE CM18 RAL Alain Blondel 14 June 2007 1 MICE run plan -- steps I and II 1.Establishing the...

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