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\ 221|50
Experimental Investigation of Few-Nucleon Dynamics at
Medium Energies
byGhanshyam Khatri
\ 222
Outline• Introduction • Three-body (3N) force• Experimental tools• BINA Detector and it’s status at CCB (Krakow)• 3N data base: present and future• Results • Conclusion
\ 223
Introduction
\ 224
Introduction
Residual of the strong forces
Nuclear Force
holds protons and neutronstogether in an atomic Nuclei
\ 225
Introduction
1935: Yukawa presented a Theory 1947: Powell proved the theory by experiments
Today , many different Theoretical models are available to exactly describe the nuclear force between any two nucleons.
Nuclear Force
(Note: Nucleons is a general term for Protons and Neutrons)
\ 226
even for the simplest Atomic Nucleuse.g. 3H and 3He
np-scattering
nd-scattering
ExperimentTheory̶� � �
. . .
High precision data from Los AlamosW. P. Abfalterer et al., PRL 81, 57 (1998)
Introduction
…but FAILS to describe Interaction between more than two nucleons!
Model [MeV]
Nijm I 7.72
Nijm II 7.62
AV18 7.62
Reid-93 7.63
Exp. 8.48
BindingEnergy
of Triton
1935: Yukawa presented a Theory 1947: Powell proved the theory by experiments
Today , many different Theoretical models are available to exactly describe the nuclear force between any two nucleons.
Nuclear Force
(Note: Nucleons is a general term for Protons and Neutrons)
\ 227
….adding 3NF in original 2NF helps !
Model 3H [MeV] 4He [MeV]
2NF 7.62 24.2
2NF +3NF 8.47 28.3
Experiment 8.48 28.4
Three-body force
V12+V23 +V31=Vtheory 3NF = V1233N System
+ =~?
\ 228
….adding 3NF in original 2NF helps !
Model 3H [MeV] 4He [MeV]
2NF 7.62 24.2
2NF +3NF 8.47 28.3
Experiment 8.48 28.4
Three-body force
V12+V23 +V31=Vtheory 3NF = V1233N System
Three-body forces in nature; example
+ =~?
\ 229
….adding 3NF in original 2NF helps !
Model 3H [MeV] 4He [MeV]
2NF 7.62 24.2
2NF +3NF 8.47 28.3
Experiment 8.48 28.4
Three-body force
V12+V23 +V31=Vtheory 3NF = V1233N System
Three-body forces in nature; example
But still there are descripancies between data and theories ! Need detailed study of 3NF.
+ =~?
Earth (and nucleon)are not point like
but having internal structure
\ 2210
Experimental Tools Nucleon - Deuteron Scattering (Relatively Simplest but not simple):
Elastic: N + d → N + d Breakup: N + d → N + N + N
Very limited phase-space rich phase-space: a large amount of kinematical config.
\ 2211
Experimental Tools Nucleon - Deuteron Scattering (Relatively Simplest but not simple):
Elastic: N + d → N + d Breakup: N + d → N + N + N
Very limited phase-space rich phase-space: a large amount of kinematical config.
deuteron-nucleon breakup reaction is best suited to
study 3N interactions
\ 2212
BINA Detector
Ball + Target
E
ΔE
Wire chamber (MWPC)
Beam
Dedicated for few-body ! High-precision data !
TARGET
Big Instrument for Nuclear-polarisation Analysis
\ 2213
BINA Detector
Ball + Target
E
ΔE
Wire chamber (MWPC)
Beam
Dedicated for few-body ! High-precision data !
TARGET
Big Instrument for Nuclear-polarisation Analysis
d
p
\ 2214
BINA in Kraków BINA @ Cyclotron Center Bronowice
2014
2012
\ 2215
3N Data Base: Present and Future
WASA 2013
KVI-2011
p or d beam data
MeV/n MeV/n
neutron beam data
Note: dot size tells angular coverage
\ 2216
3N Data Base: Present and Future
WASA 2013
KVI-2011
p or d beam data
MeV/n MeV/n
BINA@CCB FUTURE !!
Few-body program very successful
Krakow-Katowice-KVI collaboration, new Cyclotron at CCB in Krakow
Energy Range of CCB suitable for this research (50 to 230 MeV)
No need to travelling abroad, (US, Japan and now in Poland)
Strong collabration with theory group of prof Witała in UJ, Kraków
Future:polarized terget, opens a new line of research
BINA@CCB
neutron beam data
Note: dot size tells angular coverage
\ 2217
Results
Experiment performed at KVI with BINA in April 2011. beam: deuteron, energy: 160 MeV, target: Liquid Deuterium
Important Remarks: a step forward with 4N, theories are limited
d + d →d + d ... elastic
d + d → d + p + n ... three-body final stated + d → p + p + n + n ... four-body final state
d + d → d + p (+ nspectator) ... QFSd + d → p + p (+2nspectator) ... double QFS
d + d → 3H + p ... neutron transferd + d → 3He + n ... proton transfer
Theoretical calculationsWill be available for
Two-body final states
(private comunication With A. Deltuva)
d+d - EVEN MORE COMPLICATED SYSTEM
\ 2218
1824 Sept, 2014G. Khatri, MPD Symposium, Kraków
all data
Most basic analysis steps : Results
\ 2219
1924 Sept, 2014G. Khatri, MPD Symposium, Kraków
all data
Most basic analysis steps :
step 1: Presort
Results
\ 2220
2024 Sept, 2014G. Khatri, MPD Symposium, Kraków
all data
Most basic analysis steps :
step 1: Presort
Selection of the reaction-channels
d+d →d+p+n
θd =20±1, θp =30±1, φ12 =180±5
Results
step 2:
\ 2221
2124 Sept, 2014G. Khatri, MPD Symposium, Kraków
all data
Most basic analysis steps :
step 1: Presort
step 3:cross sections
OUR GOAL
θd =20±1, θp =30±1, φ12 =180±5
PRELIMINARY
Results
step 2:
Selection of the reaction-channels
d+d →d+p+n
\ 2222
visiting facilities ,
learned and gained experience
KVI, FZ-Juelich,Lisbon
BINA@CCB preparation
tests, liquid-target
expert
Grants: SONATA-BIS Preludium 7(application)
Publications&
Conferences
MPD FEW-BODYPROJECT
Achievements
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Conclusion and Outlook
Current data analysis of 160MeV data on dp and dd reactions at final stage
Theoreticians have been requested to provide calculations for dd reaction
BINA has been put into operation in Krakow, two tests with BINA were done successfully, 2013 and 2014
Future: Polarised target, we recently comunicated with Japanese expert this month.
\ 2224
Thank you for your attention !!!
\ 2225
Backup slides
\ 2226
….adding 3NF in original 2NF helps !
Model 3H [MeV] 4He [MeV]
2NF 7.62 24.2
2NF +3NF 8.47 28.3
Experiment 8.48 28.4
Introduction
3NF contribution
Hot-Spot to see 3NF: medium energies ?!
+ =~
V12+V23 +V31=Vtheory 3NF = V1233N System
\ 2227
Experimental Tools: Three-Nucleon Scattering @ Medium Energies
Elastic: N + d → N + d
θ c .m . [deg ]
θ c .m . [deg ]0 60 120 180
10 -1
0
10 1
10
without Coul.with Coul.
Relativity
Coulomb
Effects small, located at extreme angles only !
Three-body force
\ 2228
Breakup Reaction Kinematic
Three nucleons in the final state
- 9 variables Energy-momentum conservation – 4 equations
Five independent kinematical variables:
θ1, θ2, φ12=φ1-φ2, E1, E2
1H(d,pp)n measured:directions and energiesof two protons
arclength variable S
distance from kinematical
curve D
Three-body force
\ 2229
\ 2230
Introduction Ab-initio calculations for light nucleiCo
urte
sy S
. Pie
per,
Argo
nne
(+3NF)
\ 2231
Introduction Ab-initio calculations for light nucleiCo
urte
sy S
. Pie
per,
Argo
nne
(+3NF)
\ 2232
3N dynamicsThree-body forces in a NUCLEAR system !
N
N
N
3
1
3
1
2
2 jiij
i i
vm
H
\ 2233
3N dynamicsThree-body forces in a NUCLEAR system !
N
N
N
3
1
3
1
2
2 jiij
i i
vm
H
Vvm
Hji
iji i
3
1
3
1
2
2
\ 22
K. Ermisch et al., PRC 68, 054004 (2003),PRC 71, 064004 (2005)
dpdp
pd e
lasti
c sc
atter
ing
cros
s se
ction
s
34
3N dynamicsModels vs. Data