opportunity for near detector test at numi

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Opportunity for Near Detector Test at NUMI. Kevin McFarland University of Rochester 3 December 2002. Off-Axis Beams. Exploits kinematics of meson decay to produce a narrow-band beam To 0 th order, beam spectrum is function of angle and meson count - PowerPoint PPT Presentation

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Opportunity for Near Opportunity for Near Detector Test at NUMIDetector Test at NUMI

Kevin McFarlandKevin McFarlandUniversity of RochesterUniversity of Rochester

3 December 20023 December 2002

3 December 20023 December 2002 Kevin McFarlandKevin McFarland 22

Off-Axis BeamsOff-Axis Beams• Exploits kinematics of meson decay Exploits kinematics of meson decay

to produce a narrow-band beamto produce a narrow-band beam

• To 0To 0thth order, beam spectrum is order, beam spectrum is function of angle and meson countfunction of angle and meson count– Allows for a relatively straightforward Allows for a relatively straightforward

prediction of relative flux at different prediction of relative flux at different angles (energies)angles (energies)

– Can be checked by near on-axis Can be checked by near on-axis detector (MINOS or other)detector (MINOS or other)

– ABSOLUTEABSOLUTE flux has larger uncertainty flux has larger uncertainty than relative flux at different energiesthan relative flux at different energies

3 December 20023 December 2002 Kevin McFarlandKevin McFarland 33

Off-Axis BeamsOff-Axis Beams• Illustration at NUMI Illustration at NUMI

near detector sitenear detector site– Peak energy shifts Peak energy shifts

lowerlower– Width decreasesWidth decreases– High energy tail High energy tail

suppressedsuppressed– Rate significantly Rate significantly

decreaseddecreased

• Mimics far detector Mimics far detector flux at some flux at some angle…angle…

On Axis5m

10m

20m

On Axis

5m

10m20m

NUMI Near On and Off-Axis Beams(beam sim. courtesy M. Messier)

NUMI LEConfiguration

NUMI ME

3 December 20023 December 2002 Kevin McFarlandKevin McFarland 44

Possible SitesPossible Sites(NEW since EOI)(NEW since EOI)

• We have investigated possible locations within the We have investigated possible locations within the NUMI TBM drifts. No new tunneling required…NUMI TBM drifts. No new tunneling required…– Thanks to Rob Plunkett for navigational assistance!Thanks to Rob Plunkett for navigational assistance!

3 December 20023 December 2002 Kevin McFarlandKevin McFarland 55

Site 1: 5-10 meters Off-AxisSite 1: 5-10 meters Off-Axis

• Located in near hall access tunnelLocated in near hall access tunnel– Wide, with personnel access to near hallWide, with personnel access to near hall– Flat floor, easy access to shaftFlat floor, easy access to shaft

•RelativelyRelatively easy to bring utilities to site easy to bring utilities to site

Shaft

Near Hall

Absorber

10m

5m

Ditch

4.5m

6m

3 December 20023 December 2002 Kevin McFarlandKevin McFarland 66

Site 1: Interaction RatesSite 1: Interaction Rates

Shaft

Near Hall

Absorber

LE+, 10m

ME+, 10m

ME+, 5m

LE+, 5m

• Simple to move detector. <En>~2-3+ GeVSimple to move detector. <En>~2-3+ GeV– 5m gives <En>~2.8 GeV; can go higher but spectrum is broad5m gives <En>~2.8 GeV; can go higher but spectrum is broad– Ditch at upstream end; getting 15m off-axis (1.5 GeV) difficultDitch at upstream end; getting 15m off-axis (1.5 GeV) difficult

3 December 20023 December 2002 Kevin McFarlandKevin McFarland 77

Site 2: 15 meters Off-AxisSite 2: 15 meters Off-Axis

• Located just upstream of shaftLocated just upstream of shaft– Wide. Sloped floor (9%). Wide. Sloped floor (9%). – Close to shaft and utility sourceClose to shaft and utility source– Hard to move to Site 1?Hard to move to Site 1?– No separate access to absorber, muon alcovesNo separate access to absorber, muon alcoves

– <E<E>~1.5 GeV>~1.5 GeV

Shaft

Near Hall

Absorber

3 December 20023 December 2002 Kevin McFarlandKevin McFarland 88

Site 2: Interaction RatesSite 2: Interaction Rates

Shaft

Near Hall

Absorber

LE+, 15m

ME+, 15m

3 December 20023 December 2002 Kevin McFarlandKevin McFarland 99

Site 3: 5-15 meters Off-AxisSite 3: 5-15 meters Off-Axis

• Located upstream of Located upstream of absorberabsorber– Wide, unfinished tunnel. Wide, unfinished tunnel.

Sloped floor (9% grade).Sloped floor (9% grade).

• Not an attractive siteNot an attractive site– Far from shaft and utility Far from shaft and utility

sourcesource– Interferes with absorber Interferes with absorber

utitilies? Radiation? utitilies? Radiation?

– <E<E>~1.5-3+ GeV>~1.5-3+ GeV

Shaft

Near Hall

Absorber

15m

3 December 20023 December 2002 Kevin McFarlandKevin McFarland 1010

Site 3: Interaction RatesSite 3: Interaction Rates

Shaft

Near Hall

Absorber

LE+, 15m

LE+, 13m

ME+, 13m

LE+, 9m

ME+, 9m

ME+, 11m

LE+, 11m

ME+, 15m

3 December 20023 December 2002 Kevin McFarlandKevin McFarland 1111

NUMI Site SummaryNUMI Site Summary• Appropriate sites exist in the NUMI TBM Appropriate sites exist in the NUMI TBM

tunnelstunnels

– Energy Range <EEnergy Range <E>~1.5-3+ GeV>~1.5-3+ GeV

– Details…Details…•occupancy after NUMI installation (early 05?)occupancy after NUMI installation (early 05?)

•NUMI maintenance, operations conflicts?NUMI maintenance, operations conflicts?

•utilities and outfittingutilities and outfitting

•movable detector to vary angle and therefore movable detector to vary angle and therefore energyenergy

– It appears possible to avoid new excavationIt appears possible to avoid new excavation

3 December 20023 December 2002 Kevin McFarlandKevin McFarland 1212

Alternate SitesAlternate Sites• K2K “SciBar” K2K “SciBar”

DetectorDetector– Similar Similar

detectordetector– Lower rates by Lower rates by

about an order about an order of magnitudeof magnitude

– <E<E>~1.2 GeV>~1.2 GeV

K2K SciBar Event Rates

~20K Events/10 tons fid.(courtesy C. McGrew)

NUMI Near Off-AxisEvent Rates/ton

3 December 20023 December 2002 Kevin McFarlandKevin McFarland 1313

Alternate SitesAlternate Sites• BooNEBooNE

– Running now! Running now!

– <E<E>~0.9 GeV>~0.9 GeV

– Much lower rates at Much lower rates at miniBooNE detectorminiBooNE detector

•~10~1033/ton/3E20 protons/ton/3E20 protons– 100m from Target on-axis, 100m from Target on-axis,

rates and energies similar to rates and energies similar to NUMI at 1km from target, 20m NUMI at 1km from target, 20m OAOA

•3×103×1044/ton/3E20 POT/ton/3E20 POT(B. Fleming, NP02 talk)

(Fleming, NP02)

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