Transcript Hadron Production Measurements

Hadron Production
Measurements
presented by Giles Barr, Oxford
ICRR-Kashiwa
December 2004
Hadron production needed for understanding ...
Neutrino beams
spectrum, composition
Neutrino
Factories
optimisation of
pion collection
Extensive Air Showers
muon component, energy determination
Primary cosmic ray
Atmospheric
Neutrinos
π
N
N
π
K
ν
μ
Outline
Section 1: Introduction
Section 2: NA49
– Experiment
– Data taking
– Errors and corrections
Section 3: Other experiments
– HARP
– E910,MIPP
Daughter energy
Summary of measurements available
10
Boxes show importance of
phase space region for
contained atmospheric
neutrino events.
1 TeV
100
10
1 GeV
1 GeV
10
100
1 TeV
10
Parent energy
Daughter energy
Existing measurements
10
Atherton et. al.
Boxes show importance of
phase space region for
contained atmospheric
neutrino events.
SPY
Barton et. al.
1 TeV
Serpukov
Allaby et. al.
100
Eichten et. al.
Cho et. al.
Abbott et. al.
Existing measurements.
10
1 GeV
1 GeV
10
100
1 TeV
10
Parent energy
Daughter energy
PT range covered
10
Atherton et. al.
Boxes show importance of
phase space region for
contained atmospheric
neutrino events.
SPY
Barton et. al.
1 TeV
Serpukov
Allaby et. al.
100
Eichten et. al.
Cho et. al.
Abbott et. al.
Measurements.
10
1-2 pT points
3-5 pT points
>5 pT points
1 GeV
1 GeV
10
100
1 TeV
10
Parent energy
Daughter energy
New measurements
10
Boxes show importance of
phase space region for
contained atmospheric
neutrino events.
MIPP
NA49
1 TeV
100
HARP
New measurements.
10
1 GeV
1 GeV
10
100
1 TeV
10
Parent energy
Another view (MINOS)...
Atherton
400 GeV Be
Barton
100 GeV C
Spy
450 GeV Be
Plot courtesy of M. Messier
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%
Needs...
Importance of kaons at high energy
(Thanks to S. Robbins for plot)
• Pion and kaon
production
• Projectile: p, He, π, K
etc.
• Very large range of
primary energies
[2 GeV,>1 TeV]
• Target: Air nuclei
(nearby isoscalar
nuclei acceptable)
• Full phase space
coverage
• pT distribution not
interesting
• Full coverage of pT
important
NA49
NA49 experimental layout
Vertex TPCs
Main TPCs
Target
S4 counter
Gap TPC
• NA49 originally designed for Lead-Lead collisions.
• Also used for pp and pA collision physics
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.
Beam line
• Cerenkov CEDAR
counters
• Beam chambers
• Trigger S1-S3
• S4 veto
Vertex TPC 1
B=1.7T
Vertex TPC 2
B=1.7T
Main TPC
Left
Gap
TPC
Main TPC
Right
Particle ID
dE
dx
NA49 dE/dx
plots
dE/dx plot for
positives
P (GeV)
Particle ID
NA49 dE/dx fits
dE
dx
Bins
Technique:
Follow closely the
analysis of p-p
data
xF and pT bins
Some corrections
are identical
Pion analysis
•
Analysis:
1. Get pion yields for proton-proton,
2. followed by pion yields for proton-carbon
3. 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 π and p
dE/dx curves overlap. Use reflection in p-p.
– Almost no information at negative xF
Corrections and errors on pion yields
Binning correction
~1%
Target re-interaction
<1%
Detector material interaction
<1%→few %
S4 trigger correction
5-15%
Feed down correction
K0, Λ0, Σ decays
Pion→Muon decay
In progress
K→pion decay
small
small
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.
HARP
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
TPC, momentum
and PID (dE/dX)
at large Pt
1.5 T dipole spectrometer
Drift Chambers:
Tracking
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 spill=400ms. Event rate ˜ 2.5KHz
• Corresponds to some 106 events/day
•  Very demanding (unprecedented!) for the TPC.
Beam Particle Identification
p
3.0 GeV/c beam
p
K
d
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 >98.7%
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
Forward PID: TOF Wall
Separate p/p (K/p) at low momenta (0–4.5 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
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
3s separation:
2


t

t
 wall 0 
2
2
m  p  
  1
 L 

Pion yield: K2K thin target
5%l Al target (20mm)
Use K2K thin target (5%l)
• To study primary p-Al interaction
• To avoid absorption / secondary interactions
K2K replica (650mm)
p > 0.2 GeV/c
|y | < 50 mrad
25 < |x| < 200 mrad
Raw data
0
2
4
6
p-e/p misidentification
background
8
10
P(GeV/c)
-200 -100
0
100 200
x(mrad)
Y. Fisyak
Brookhaven National Laboratory
R. Winston
EFI, University of Chicago
M.Austin,R.J.Peterson
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.Onel, 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.
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
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
Summary
HARP 3-15 GeV at CERN PS
MIPP 5-120 GeV at FNAL MI
NA49 100,160 GeV at SPS