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Precision measurements by NOMAD

Precision measurements by NOMAD
Dmitry V.Naumov (on b ehalf of NOMAD Collab oration)
JINR

LOMONOSOV CONFERENCE ON ELEMENTARY PARTICLE PHYSICS. 21/08/2009


Precision measurements by NOMAD NOMAD Exp eriment

Outline
1 NOMAD Exp eriment 2 Recent and Ongoing Analyses

Total cross-section Quasi-Elastic cross-section Coherent 0 production Dimuons NC/CC measurement Fragmentation and Fracture functions 0 Production in -Interactions Other ongoing analyses
3 Summary


Precision measurements by NOMAD NOMAD Exp eriment

Neutrino Oscillation MAgnetic Detector
Neutrino b eam

BCT1

SEMs

Al Collimator Horn

Reflector

BCT2

CHORUS Muon Pits Decay Earth Tunnel

Be Target

450 GeV/c protons

TDX collimator

Iron Shield

NOMAD

Primary goal: Е oscillations with m2 5eV 2 (best cosmological guess at that time) Data taking 1994-1998 Neutrino and Anti-Neutrino modes Two dedicated detectors: CHORUS and NOMAD NOMAD was 835 m from the B e target and 620 m from the decay region


Precision measurements by NOMAD NOMAD Exp eriment

Neutrino Oscillation MAgnetic Detector
Neutrino b eam

Neutrinos / m / 3 GeV / 10 p.o.t.

10 6

Neutrino Flux

9

Е , Е , e , e ? ? 1 < E < 300 GeV Б and K Б by the SPY experiment constrained neutrino flux predictions E Rel.Abund. 23.6 1.000 22.7 0.07 37.0 0.01 33.2 0.003

10

5

2

10 4

10 3

10 2

10

1

0

20

40

60

80

100

120

Neutrino Energy (GeV)

Е Е e e


Precision measurements by NOMAD NOMAD Exp eriment

Neutrino Oscillation MAgnetic Detector
The detector

Muon Chambers Front Calorimeter
V8

Dipole Magnet

TRD Modules Preshower

Neutrino Beam

Drift Chamber Target - 2.7 tons, = 0.1g /cm3 Front Calorimeter Target - 17.7 tons Aluminium Coil |B| = 0.4 Tesla

1 metre

Veto Planes Drift Chambers

Trigger Planes Electromagnetic Calorimeter Hadronic Calorimeter


Precision measurements by NOMAD NOMAD Exp eriment

Neutrino Oscillation MAgnetic Detector
The detector

p p



0.05 L



0.008зp L5

Full event kinematics reconstruction Over 1.7 millions -interactions recorded in Drift Chamb ers Over 2 millions -interactions recorded in Al-coil Over 20 millions -interactions recorded in Fe-scintillator calorimeter

Best current limit on Е Record statistics and excellent resolution lead to a wide physics research program:
More than 20 papers More than 700 citations Several ongoing precision analyses


Precision measurements by NOMAD NOMAD Exp eriment

Neutrino Oscillation MAgnetic Detector
The detector

p p



0.05 L



0.008зp L5

Full event kinematics reconstruction Over 1.7 millions -interactions recorded in Drift Chamb ers Over 2 millions -interactions recorded in Al-coil Over 20 millions -interactions recorded in Fe-scintillator calorimeter

Best current limit on Е Record statistics and excellent resolution lead to a wide physics research program:
More than 20 papers More than 700 citations Several ongoing precision analyses


Precision measurements by NOMAD NOMAD Exp eriment

Neutrino Oscillation MAgnetic Detector
The detector

p p



0.05 L



0.008зp L5

Full event kinematics reconstruction Over 1.7 millions -interactions recorded in Drift Chamb ers Over 2 millions -interactions recorded in Al-coil Over 20 millions -interactions recorded in Fe-scintillator calorimeter

Best current limit on Е Record statistics and excellent resolution lead to a wide physics research program:
More than 20 papers More than 700 citations Several ongoing precision analyses


Precision measurements by NOMAD Recent and Ongoing Analyses

Outline
1 NOMAD Exp eriment 2 Recent and Ongoing Analyses

Total cross-section Quasi-Elastic cross-section Coherent 0 production Dimuons NC/CC measurement Fragmentation and Fracture functions 0 Production in -Interactions Other ongoing analyses
3 Summary


Precision measurements by NOMAD Recent and Ongoing Analyses

Precision measurements
Completed precision measurements Total Е N charged current cross-section in 2.5 < E < 40 GeV Е n Е- p QEL cross-section (talk by Jean-Michel) Coherent 0 production in neutral current N interactions Ongoing precision measurements Measurement of strange sea and charm mass in Е+ Е- production First Measurement of (N C )/ (C C )(Ehad ) in 1 < Ehad < 100 GeV 0 Production in -Interactions First Measurement of Production in -Interactions Б production yields and measurement of fragmentation and fracture functions Plus More


Precision measurements by NOMAD Recent and Ongoing Analyses Total cross-section

Total Е CC cross-section

EЕ -scale error 0 constrained by KS mass < 0.2% E
had

-scale error 0.6%

Cross-section error is dominated by rel.flux e rro r 4% for 2.5 < E < 10 GeV 2.6% for 10 < E < 40 GeV
Phys. Lett. B 660, 19 (2008) [arXiv:0711.1183 [hep-ex]].


Precision measurements by NOMAD Recent and Ongoing Analyses Quasi-Elastic cross-section

QEL Е n Е- p cross-section

Accepted to EPJ C


Precision measurements by NOMAD Recent and Ongoing Analyses Coherent 0 pro duction

Coherent 0 pro duction in N NC interactions

0 (Coherent and not only) in N NC - main background (up to 60%) for e app earance in LBL exp eriments Select events with only two s (no Е, no other tracks) Require s to convert in DC e+ e- Use Data to predict the background Measure cross-secion


Precision measurements by NOMAD Recent and Ongoing Analyses Coherent 0 pro duction

Coherent 0 pro duction in N NC interactions
Coherent 0 candidate

Red crosses з used in the reconstructed tracks, black з are not used.


Precision measurements by NOMAD Recent and Ongoing Analyses Coherent 0 pro duction

Coherent 0 pro duction in N NC interactions

Experiment Aachen-Padova Gargamelle CHARM SKAT 15 BC MiniBooNE NOMAD

Nucleus 27 30 20 30 20 CH2 12.8

E GeV 2 2 30 7 20 1.2 24.3

(C oh 0 ) 10-40 cm2 /A (29 Б 10) (31 Б 20) (96 Б 42) (79 Б 28) (0.20 Б 0.04) N/A (72.6 Б 10.6)

C oh 0 /Е C C 10-3

(4.3 Б 1.5) N/A (3.21 Б 0.46)


Precision measurements by NOMAD Recent and Ongoing Analyses Dimuons

All the dimuon data
Exp. N CDHS NuTeV CCFR CHORUS NOMAD N ? CDHS NuTeV CHORUS CHORUS Jun Feb Feb Apr 1982 2001 2001 2008 171 1458 1060 430 30 - 250 (> 100) 20 - 400 (157.8) 30 - 600 (> 100) 10 - 240 (27) Jun Feb Feb Apr 1982 2001 2001 2008 660 5102 5030 8910 17k exp. 30 - 250 (> 100) 20 - 400 (157.8) 30 - 600 (> 100) 10 - 240 (27) 6 - 300 (24.3) Publ. Stat. (NЕЕ ) E (GeV)

The NOMAD experiment has the highest statistics and is closer to the charm production threshold


Precision measurements by NOMAD Recent and Ongoing Analyses Dimuons

Charm dimuon distributions
Charm

events

2.2 2 1.8 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 0

DATA MC N = 16574 /Ndf = 3.299
2

events

з10

3

Charm

з10

3

1.6 1.4 1.2 1 0.8 0.6 0.4 0.2
2

DATA MC N = 17305 /Ndf = 2.472

5

10

15

20

25

30
rec Е
c

0

50

100

150

200

250

300

p

(GeV/c)

E

rec

(GeV)

Charm

events

2.2 2 1.8 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 0 0

DATA MC

events

з10

3

Charm

з10

3

DATA

1.4 1.2 1 0.8 0.6 0.4 0.2

MC N = 17304 2 /Ndf = 2.083

N = 17281 2 /Ndf = 2.691

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1
rec Bj

0 0

2

4

6

8

10

12

14

16
rec

18

20

x

s

(GeV/c2 )


Precision measurements by NOMAD Recent and Ongoing Analyses Dimuons

Exp ected NOMAD uncertainties
I can not show you the results yet...
(%)
syst

2 1.5 1 0.5 0 10 102

NOMAD uncertainties Value (%) Stat. 5.0 - 6.0 Syst. 2.5

E (GeV)


Precision measurements by NOMAD Recent and Ongoing Analyses NC/CC measurement

(N C )/ (C C ) as a function of E

had

NC/CC

0.6

0.5

2.5% for E GeV 5% for E GeV

had

>5

0.4

had

2

0.3

Corresponds to YB j > 0.04 Will improve background predictions for LBL
1 10 10 Ehad (GeV)
2

0.2

0.1

0


Precision measurements by NOMAD Recent and Ongoing Analyses Fragmentation and Fracture functions

Charged Pions
pro duction. Fragmentation and fracture functions
+ production - production
NuN (NOMAD) ep (HERMES)

dn/dz

dn/dz

NuN (NOMAD)

10

ep (HERMES)

10

1 1

10-1 10
-1 -3

10

10-2

10-1

10

-3

10-2

10-1

z

z

The lowest z is 30 times smaller than that of HERMES The plots include only 1/4 of the total NOMAD statistics.
We will measure Dq (z ) and fracture functions with best accuracy.


Precision measurements by NOMAD Recent and Ongoing Analyses 0 Pro duction in -Interactions

Inclusive

0

Pi0: Clus/Clus
12000 10000 8000 6000 4000 2000 0 0.05 0.075 9000 8000 7000 6000 5000 4000 3000 2000 1000 0 0.05 0.075 0.1 0.1

Total => 100,900 Rec-Pi0's
signal=71595.4

0.125 0.15 0.175
Dt Ph2

M

0.2 0

0.225 0.25 0.275
Cl/Cl

0.3

0.125 0.15 0.175

0.2

0.225 0.25 0.275

0.3


Precision measurements by NOMAD Recent and Ongoing Analyses Other ongoing analyses

Other ongoing analyses

Differential Е N charged current DIS cross-section Checking the NuTeV Dimuon Anomaly Measurement of nuclear effects from (Е F e)/ (Е C ) in the same experiment Checking Е /e universality Inclusive 0 production


Precision measurements by NOMAD Summary

Outline
1 NOMAD Exp eriment 2 Recent and Ongoing Analyses

Total cross-section Quasi-Elastic cross-section Coherent 0 production Dimuons NC/CC measurement Fragmentation and Fracture functions 0 Production in -Interactions Other ongoing analyses
3 Summary


Precision measurements by NOMAD Summary

Summary
The NOMAD experiment accumulated the highest resolution Е /Е /e /e data in 2.5 < E < 300 GeV. The ? ? analyses are still ongoing A number of precision measurements performed A list of ongoing analyses A rich physics can be extracted from: Over 1.7 millions -interactions recorded in Drift Chamb ers Over 2 millions -interactions recorded in Al-coil Over 20 millions -interactions recorded in Fe-scintillator calorimeter

T HA NK Y OU !


Precision measurements by NOMAD Summary

Summary
The NOMAD experiment accumulated the highest resolution Е /Е /e /e data in 2.5 < E < 300 GeV. The ? ? analyses are still ongoing A number of precision measurements performed A list of ongoing analyses A rich physics can be extracted from: Over 1.7 millions -interactions recorded in Drift Chamb ers Over 2 millions -interactions recorded in Al-coil Over 20 millions -interactions recorded in Fe-scintillator calorimeter

T HA NK Y OU !


Precision measurements by NOMAD Summary

Summary
The NOMAD experiment accumulated the highest resolution Е /Е /e /e data in 2.5 < E < 300 GeV. The ? ? analyses are still ongoing A number of precision measurements performed A list of ongoing analyses A rich physics can be extracted from: Over 1.7 millions -interactions recorded in Drift Chamb ers Over 2 millions -interactions recorded in Al-coil Over 20 millions -interactions recorded in Fe-scintillator calorimeter

T HA NK Y OU !


Precision measurements by NOMAD Summary

Summary
The NOMAD experiment accumulated the highest resolution Е /Е /e /e data in 2.5 < E < 300 GeV. The ? ? analyses are still ongoing A number of precision measurements performed A list of ongoing analyses A rich physics can be extracted from: Over 1.7 millions -interactions recorded in Drift Chamb ers Over 2 millions -interactions recorded in Al-coil Over 20 millions -interactions recorded in Fe-scintillator calorimeter

T HA NK Y OU !


Precision measurements by NOMAD Summary

Summary
The NOMAD experiment accumulated the highest resolution Е /Е /e /e data in 2.5 < E < 300 GeV. The ? ? analyses are still ongoing A number of precision measurements performed A list of ongoing analyses A rich physics can be extracted from: Over 1.7 millions -interactions recorded in Drift Chamb ers Over 2 millions -interactions recorded in Al-coil Over 20 millions -interactions recorded in Fe-scintillator calorimeter

T HA NK Y OU !


Precision measurements by NOMAD Summary

Summary
The NOMAD experiment accumulated the highest resolution Е /Е /e /e data in 2.5 < E < 300 GeV. The ? ? analyses are still ongoing A number of precision measurements performed A list of ongoing analyses A rich physics can be extracted from: Over 1.7 millions -interactions recorded in Drift Chamb ers Over 2 millions -interactions recorded in Al-coil Over 20 millions -interactions recorded in Fe-scintillator calorimeter

T HA NK Y OU !