Hadron Production Measurements

1
Hadron Production Measurements

• presented by Giles Barr, Oxford
• ICRR-Kashiwa
• December 2004

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Hadron production needed for understanding ...
Neutrino beams spectrum, composition
Neutrino Factories optimisation of pion
collection
Extensive Air Showers muon component, energy
determination
3
Atmospheric Neutrinos
4
Outline

• Section 1 Introduction
• Section 2 NA49
• Experiment
• Data taking
• Errors and corrections
• Section 3 Other experiments
• HARP
• E910,MIPP

5
Summary of measurements available
10
Boxes show importance of phase space region for
contained atmospheric neutrino events.
Daughter energy
1 TeV
100
10
1 GeV
1 GeV
10
100
1 TeV
10
Parent energy
6
Existing measurements
Boxes show importance of phase space region for
contained atmospheric neutrino events.
Existing measurements.
10
7
PT range covered
Boxes show importance of phase space region for
contained atmospheric neutrino events.
SPY
Atherton et. al.
Barton et. al.
Serpukov
Allaby et. al.
Eichten et. al.
Cho et. al.
Abbott et. al.
Measurements. 1-2 pT points 3-5 pT
points gt5 pT points
8
New measurements
Boxes show importance of phase space region for
contained atmospheric neutrino events.
MIPP
NA49
HARP
New measurements.
9
Another view (MINOS)...
Atherton 400 GeV Be
Barton 100 GeV C
Spy 450 GeV Be
Plot courtesy of M. Messier
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NA20 (Atherton et al.), CERN-SPS (1980)

• H2 beam line in the SPS north-area

• Secondary energy scan 60,120,200,300 GeV

Overall quoted errors Absolute rates
15 Ratios 5
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Needs...

• Pion and kaon production
• Projectile p, He, p, K etc.
• Very large range of primary energies 2
  GeV,gt1 TeV
• Target Air nuclei (nearby isoscalar nuclei
  acceptable)
• Full phase space coverage
• pT distribution not interesting
• Full coverage of pT important

Importance of kaons at high energy (Thanks to S.
Robbins for plot)
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NA49
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NA49 experimental layout
Vertex TPCs
Main TPCs
Target
S4 counter
Gap TPC
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• NA49 originally designed for Lead-Lead
  collisions.
• Also used for pp and pA collision physics

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NA49 Proton-Carbon run

• P322 group consisting of some atmospheric
  neutrino flux calculators, HARP experimentalists
  and MINOS experimentalists formed collaboration
  with NA49 and proposed a series of measurements.
  
• Received a 1 week test run with a carbon target.
• It took place in June 2002.
• 158 GeV run, 500k triggers.
• 100 GeV run, 160k triggers.
• 1 interaction length carbon target.
• Proton selected beam (using Cerenkov).
• TPCs, HCAL, CD, no TOF.
• Immediately preceeding run was an NA49
  proton-proton run, using a liquid hydrogen
  target.

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Beam line

• Cerenkov CEDAR counters
• Beam chambers
• Trigger S1-S3
• S4 veto

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Main TPC Left
Vertex TPC 1 B1.7T
Vertex TPC 2 B1.7T
Gap TPC
Main TPC Right
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NA49 dE/dx plots
Particle ID
dE/dx plot for positives
P (GeV)
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NA49 dE/dx fits
Particle ID
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Bins

• Technique
• Follow closely the analysis of p-p data
• xF and pT bins
• Some corrections are identical
• Pion analysis

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• Analysis
• Get pion yields for proton-proton,
• followed by pion yields for proton-carbon
• Later, do kaons, antiprotons.
• Pion extraction straightforward
• shifts and resolution easy to determine
• Above xF 0.5, dE/dx information not available
  near gap. We do have the track distributions.
• Particular region at low xF where p and p dE/dx
  curves overlap. Use reflection in p-p.
• Almost no information at negative xF

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Corrections and errors on pion yields
Binning correction 1
Target re-interaction lt1
Detector material interaction lt1?few
S4 trigger correction 5-15
Feed down correction K0, ?0, S decays In progress
Pion?Muon decay small
K?pion decay small
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Prospects

• Pions for proton-proton available shortly.
• Pions for proton-carbon follow rapidly after
  this.
• Some atmospheric specific changes can be made
• Use XLAB
• Feed down required ?
• Kaon yields is next priority
• Extraction not too bad in positives NK not
  strongly correlated to K-peak position.
• Challenge at high xF in negatives.

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HARP
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The Harp detector Large Acceptance, PID
Capabilities , Redundancy
Threshold gas Cherenkov p identification at
large Pl
TOF p identification in the low Pl and low Pt
region
Drift Chambers Tracking and low Pt spectrometer
EM filter (beam muon ID and normalization)
Target-Trigger
0.7T solenoidal coil
Drift Chambers Tracking
TPC, momentum and PID (dE/dX) at large Pt
1.5 T dipole spectrometer
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HARP Experiment

• Beam 3-15 GeV protons, CERN PS
• Collected data 2001, 2002
• Secondary hadron yields
• Beam momenta
• As a function of momentum and angle of daughter
  particles
• For different daughter particles
• As close as possible to full acceptance
• The aim is to provide measurements with few
  overall precision
• ? efficiencies must be kept under control, down
  to the level of 1
• primarily trough the use of redundancy from one
  detector to another
• Thin, thick and cryogenic targets LH2, LD2, LO2
  LN2 Be, C, Al, Cu, Tn, Sn, Pb
• T9 secondary beam line on the CERN PS allows a
  2?15 GeV energy range
• O(106) events per setting
• A setting is defined by a combination of target
  type and material, beam energy and polarity
• Fast readout
• Aim at 103 events/PS spill, one spill400ms.
  Event rate 2.5KHz
• Corresponds to some 106 events/day
• ? Very demanding (unprecedented!) for the TPC.

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Beam Particle Identification

• Beam Time Of Flight (TOF)
• separate p/K/p at low energy
• over 21m flight distance
• time resolution 170 ps after TDC and ADC
  equalization
• proton selection purity gt98.7

p
p
3.0 GeV/c beam
K
d
12.9 GeV/c (K2K) Beam
p/d
p

• Beam Cherenkov
• Identify electrons at low energy, p
• at high energy, K above 12 GeV
• 100 eff. in e-p tagging

K
Cherenkov ADC
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Forward PID TOF Wall

• Separate p/p (K/p) at low momenta (04.5 GeV/c)
• 42 slabs of fast scintillator read at both ends
  by PMTs

3 GeV beam particles
PMT
data
p
Scintillator
p

• TOF time resolution 160 ps
• 3s separation p/p up to 4.5 GeV/c
• K/p up to 2.4 GeV/c
• ? 7s separation of p/p at 3 GeV/c

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Pion yield K2K thin target
5l Al target (20mm)

• Use K2K thin target (5l)
• To study primary p-Al interaction
• To avoid absorption / secondary interactions

K2K replica (650mm)
p gt 0.2 GeV/c ?y lt 50 mrad 25 lt ?x lt 200
mrad
Raw data
4
2
6
8
10
0
100
200
-100
-200
0
qx(mrad)
P(GeV/c)
p-e/p misidentification background
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Y. Fisyak Brookhaven National Laboratory R.
Winston EFI, University of Chicago M.Austin,R.J.Pe
terson University of Colorado, Boulder, E.Swallow
Elmhurst College and EFI W.Baker,D.Carey,J.Hylen,
C.Johnstone,M.Kostin, H.Meyer, N.Mokhov, A.Para,
R.Raja,S. Striganov Fermi National Accelerator
Laboratory G. Feldman, A.Lebedev, S.Seun Harvard
University P.Hanlet, O.Kamaev,D.Kaplan,
H.Rubin,N.Solomey, C.White Illinois Institute of
Technology U.Akgun,G.Aydin,F.Duru,Y.Gunyadin,Y.One
l, A.Penzo University of Iowa N.Graf, M.
Messier,J.Paley Indiana University P.D.BarnesJr.,E
.Hartouni,M.Heffner,D.Lange,R.Soltz,
D.Wright Lawrence Livermore Laboratory R.L.Abrams,
H.R.Gustafson,M.Longo, H-K.Park,
D.Rajaram University of Michigan A.Bujak,
L.Gutay,D.E.Miller Purdue University T.Bergfeld,A.
Godley,S.R.Mishra,C.Rosenfeld,K.Wu University of
South Carolina C.Dukes, H.Lane,L.C.Lu,C.Maternick,
K.Nelson,A.Norman University of Virginia 50
people, 11 graduates students, 11 postdocs.
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MIPP Physics Program

• Particle Physics-To acquire unbiased high
  statistics data with complete particle id
  coverage for hadron interactions.
• Study non-perturbative QCD hadron dynamics,
  scaling laws of particle production
• Investigate light meson spectroscopy,
  pentaquarks, glueballs
• Nuclear Physics
• Investigate strangeness production in nuclei-
  RHIC connection
• Nuclear scaling
• Propagation of flavor through nuclei

• Netrinos related Measurements
• Atmospheric neutrinos Cross sections of protons
  and pions on Nitrogen from 5 GeV- 120 GeV
  (5,15,25,5070,90) GeV
• Improve shower models in MARS, Geant4
• Make measurements of production of pions for
  neutrino factory/muon collider targets
• MINOS target measurements pion production
  measurements to control the near/far systematics
• Complementary with HARP at CERN

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E910

• Note added after end of talk
• The nw BNL measurements with the E910 experiment
  have been reported by J. Link at NuFact 2004 in
  WG2

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Summary

• HARP 3-15 GeV at CERN PS
• MIPP 5-120 GeV at FNAL MI
• NA49 100,160 GeV at SPS