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Status of three-nucleon force study by nucleon-deuteron system
Status of three-nucleon force study by nucleon-deuteron system
August 22, 2006FB18, Santos, Brazil
1. Introduction
2. dp elastic measurements by NUCLOTRON at DUBNA
3. How far we understand 3NF effects?
4. How data are reliable ?
5. Facilities
6. Summary
H. Sakai
Department of Physics
The University of Tokyo
1. Introduction
How 3NF are established
by experiments?
How to study 3NF?
2BS
3BS
2NF
3NF
3NF is much smaller than 2NF.
→ 3NF effects are easily masked by 2NF effects.
1 Equations of motion for 3BS must be solved exactly. →Faddeev eq.
2 Realistic modern 2NF must be established. x2 1 for 4,000 data points.
CD Bonn AV18
Nijmegen I/II Main differences are off-shell properties.3 2πexchange 3NF (Fujita-Miyazawa)
TM99 Urbana IX (U9)
New development in theory
1 PT
2 Relativistic effects
3 Coulomb effects
Why Nd measurements at intermediate energies?
•H.Witała et al., PRL 81(1998) 1183.
→ Go to higher energies for Nd elastic scatt.
and look at X-sec. minimum region.
Typical mom. transfer: 1.5--3 fm-1 for Nd scatt. at intermediate energies.
D-state of deuteron mainly contributes in the reaction.
At intermediate energy, this may correspond to x-sec. min.
internal mom. dist. of deuteron
Reactions for Nd system
Observables (Nd-sys.)
d/d
AP (Ay, iT11, T20, T21, T22) VLS, (VLS)2, VT, D-state
PT (Kij, Kij
k) V (spin-spin int.)
SC (Ci,j, Ci,jk, Cij,k) V
q(fm-1)@135 MeV1 elastic scattering 0--2.4--3.4 (0º--90º--180º)
2 breakup (FSI, QFS, Space star) 0--3
3 capture 2.5--3.5 (0º--180º), MEC
Cross section/AP meas.
pd
nd np n
d
p
d
p/d p
difficulties of measurements
p/dp
d
L
RPT
characteristic
Cross section : absolute quantity systematic errors
Pol. Obs. : relative quantity
normalize to pp scatt.
normalize to np scatt.
tiny yield (difficult exp.)
Pol. transfer meas.
polarimeter calibration
small yield (difficult exp.)
Present achievement of experiments @ intermediate energies
Recent tendency of experiments @ intermediate energies
1 higher bombarding energies R3-17 Tamii et al. pd-392 MeV
2 nd data become available R3-16 Maeda et al. nd-250 MeV
3 breakup 2πcoverage, PT R2- Kystrin et al. dp-130 MeV (cancelled)
R3-15 Mardanpour et al. dp-190 MeV 2πcoverage R3-25 Sekiguchi et al. dp-270 MeV PT
4 radiative capture R3-18 Messchendorp et al. dp-190 MeV -coinc.
R3-24 Tameshige et al. dp-137 MeV
5 four-nucleon system R3-20 Miki et al. dd-270 MeV DFSI
Please come to “Experimental Few-Body session”, Room 3, Friday (Aug. 25)
RIKEN exp.
DUBNA exp.
2 dp elastic measurements
by
NUCLOTRON at DUBNA
Nuclotron at JINR, Dubna
superconducting synchrotron (E/A < 6 GeV)
• Nuclear structure• Medium effects on particle production• Modification of nuclear matter• Hypernuclei and nuclei• Nucleon structure
d-p elastic scattering measurement at NUCLOTRON
Internal Target Station
30-pairs plastic scintillation counterstarget:CH2(10 m)
Measurements at 270 MeV, 880 MeV and 2 GeVby Uesaka/Ladygin et al.
Ay ~ 0.3 ; moderately large
Ayy ; large only at cm 0 deg
insufficient statistics due to small beam intensity
→ strong beam with new ion source CIPIOS
d-p Analyzing powers at 880 MeV
Beam Intensity < 2-3 x107 /spillPolarizations (pZ, pZZ)=(+1/3,+1),(+1/3,-1), (0,0)
measured values: (preliminary) pZ pZZ
mode 1 -0.207 ± 0.044 0.879 ± 0.116 mode 2 -0.176 ± 0.035 -0.421 ± 0.093
Results
Suda et al.
R3-17 Tamii pd-392 MeV
3 How far we understand 3NF effects?
Success and failure
Success & failure
1 d/d, vector AP(Ay), PT(Kijk) (Tp135 MeV)
very successful
2 tensor AP, PT, SC
some successful, some not.
confusing, chaotic!
3 d/d (Tp>200 MeV)
large discrepancy in backward angles
(nucleon-exchange process)
due to 3NF? / relativity? / ?
Success 1 d/d, vector AP(Ay) , PT(Kij
k) (Tp135 MeV)
very successful
Sekiguchi et al.
NN only
NN+3NF(TM99)
AV18+3NF(U9)
CDBonn+△
Coulomb
Failure?2 iT11, Tij, PT some successful, some not.
confusing, chaotic!
Sekiguchi et al.
NN only
NN+3NF(TM99)
AV18+3NF(U9)
CDBonn+△
Failure? 3 d/d ? (Tp>200 MeV)
R3-17 Maeda nd elastic scattering measurements at En=250MeV
Calc. even including 3NF still underestimate the data by 50% !
nucleon-exchange process ?
Relativistic calc. by Witala improve the fit only at θcm > 160 deg. but not enough.
Doleschall approx. by Kamada
Screened Coulomb by Deltuva
Coulomb effects ? (too large !)
4 How data are reliable ?
Inconsistency between data sets
Consistency between data sets
1 d/d(Tp=135 MeV) pd-elastic scatt.
RIKEN vs. KVI
2 Axx ,Ayy (Td=200 MeV) dp-radiative capture
RCNP vs. KVI
Different group data-sets are consistent?
3NF effects are at most 30% effect.
Consistency among data sets
1 d/d(Tp=135 MeV) pd-elastic scatt. RIKEN vs. KVI
○ N. Sakamoto, PL B367 (1996)60.
● H. Sakai, PRL 84(2000)5288.
● K. Sekiguchi, PR C65(2002)34003.
▲ K. Ermisch, PR C68(2003)51001.
○ K. Sekiguchi, PRL 95(2005)162301.
How do you judge?
NN only
NN+3NF(TM99)
AV18+3NF(U9)
CDBonn+△
Consistency among data sets
2 Axx , Ayy (Td=200 MeV) dp-radiative capture
RCNP vs. KVI
d+pd+p33He+He+ @ 200 MeV/A @ 200 MeV/A
No anomaly observed In KVI data!!
Sagara, Preliminary
— Hanover (virt. ) Deltuva, PRC67, 034001(03)
— Bochum/Cracow (MEC) Skibinski, PRC67, 054001(03)
— Bochum/Cracow (Sieg.) Skibinski, PRC67, 054001(03)
KVI, PL B Mehmandoost/van Garderen
Ayy Axx
Ayy Axx
d+pd+p33He+He+ @ @ 270270 MeV/A at RIKEN MeV/A at RIKENOne of the last experiment at SMART.
by Suzuki et al. by Sekiguchi et al.
Another confusion !
270 MeV
200 MeV
5 Facilities
Facilities
1. Phase out from nuclear physics experiment
• IUCF (2002) pol-p, d
• TSL (2005) n-fac.
• RIKEN (2005) pol-d
• KVI (2007) pol-p,d (soon)
2. Active
• RCNP pol-p(<400 MeV), pol-d(<200 MeV), n-fac.
• LANL n-fac.
• NUCLOTRON pol-d(<6 GeV)
• COSY pol-p, pol-d
• iThemba(NAC) p,d
3. Coming
• RIKEN RIBF pol-d(400-880 MeV)
Beam Line Polarimeter
dp elastic/breakup Measurement
Polarized Ion Sourcevector & tensor pol. d
RIKEN RIBF
Polarized d (400-880 MeV) available
in 2008(?)
SMART
Pol. d (140-270 MeV) Contact person: Dr. K. Sekiguchi
SMART spectrometer
Most of the 3NF studies were performed
by using the magnetic spectrometer SMART!
Facilities1. Phase out for nuclear physics experiment
• IUCF (1998) pol-p, d• TSL (2005) n-fac.• RIKEN (2005) pol-d • KVI (2007) pol-p,d (soon)
2. Active• RCNP pol-p(<400 MeV), pol-d(<200 MeV), n-fac.• NUCLOTRON pol-d(<6 GeV)• COSY pol-p(<1GeV), pol-d(?)• iThemba(NAC) p(<200 MeV), d(<80 MeV)• LANL n-fac.(<800 MeV)
3. Coming• RIKEN RIBF pol-d(400-880 MeV)
Theory
Without exact calc., nothing can be conclusive!
Key to the few-body study!
6 Summary
Summary
─ Tendency of 3NF study.
1. Higher energies DUBNA exp.
2. nd measurement
3. Breakup
4. Readiative capture
─ 3NF are successful? (comparison to theories)
1. d/d, Ay Tp135 MeV good fits
2. Tp>200 MeV fail, 50% off. small rel. effects.
(nd)/(pd) Coulomb ?
3. Tensor AP, PT confusing, chaotic!
dp-breakup measurement at 270 MeV at RIKEN
R3-25 Sekiguchi
another confusion ! ?
vector AP tensor AP tensor-to-vector PT
1=27°-35°, 2=31°, 12 = 180°
Summary─ Tendency of 3NF study.
1. Higher energies DUBNA exp.
2. nd measurement
3. Breakup
4. Readiative capture
─ How present 3NF are successful. (comparison to theories)
1. d/d, Ay Tp135 MeV good fits
2. Tp>200 MeV fail, 50% off. small rel. effects.
(nd)/(pd) Coulomb ?
3. Tensor AP, PT confusing, chaotic!
─ Consistencies between data sets
1. d/d at Tp=135 MeV
2. Radiative capture
─ Facilities
How far we understand 3NF, that is the question.
Collaborators
•Jagiellonian Univ.H. Witala, J. Golak
• KITH. Kamada
• BochumW. Glockle
• Honnove P.U. Sauerr• Lisbon A. Deltuva
• University of Tokyo
• RCNP
• RIKEN
• Kyushu University
• TITech
• Saitama University
This talk is helped by
K. Sekiguchi (RIKEN)
Y. Meda (U. Tokyo)
K. Suda (U. Tokyo)
J. Messchendorp (KVI)
Experiments Theory
Announcements.
The 23rd International Nuclear Physics Conferencewith a special session in commemoration of the centenn
ial of the birth of Prof. Hideki Yukawa
June 3(Sun)-8(Fri), 2007Tokyo International Forum, Tokyo
hosted byKEK, RIKEN, RCNP, JAEA, JWE and Yukawa Memorial Foundation
sponsored byIUPAP, The Science Council of Japan, The Physical Society of Japan
The Organizing Committee chaired by Shoji Nagamiya (KEK)
homepage: http://www.inpc2007.jpfor pre-registration email: [email protected]
Organizers: Organizers: H. Sakai (UT) (chair)H. Sakai (UT) (chair) K. Hatanaka (RCNP)K. Hatanaka (RCNP) H. Okamura (RCNP)H. Okamura (RCNP) K. Sagara (Kyushu)K. Sagara (Kyushu) Y. Suzuki(Nigata)Y. Suzuki(Nigata) Y. Akaishi (Nihon/RIKEN)Y. Akaishi (Nihon/RIKEN) T. Motobayashi(RIKEN)T. Motobayashi(RIKEN) K. Sekiguchi (RIKEN) (secretary)K. Sekiguchi (RIKEN) (secretary)Topics to be covered :Topics to be covered :
- Few Nucleon Systems and Three Nucleon Force- Few Nucleon Systems and Three Nucleon Force - Chiral Effective Field Theory- Chiral Effective Field Theory - Three Nucleon Force Effects in Nuclear Structure- Three Nucleon Force Effects in Nuclear Structure - Three Nucleon Forces in Hyper Nuclei- Three Nucleon Forces in Hyper Nuclei
International Symposium onInternational Symposium on
New Facet of Three Nucleon ForceNew Facet of Three Nucleon Force~ ~ 50 years of Fujita-Miyazawa Three Nucleon Force50 years of Fujita-Miyazawa Three Nucleon Force ~~
October 29(Mon.) - 31(Wed.), 2007October 29(Mon.) - 31(Wed.), 2007Koshiba Hall, University of TokyoKoshiba Hall, University of Tokyo
End
Thank you for your attention.
Four nucleon system is interesting.
2BS
3BS
2NF
3NF
4BS 4NF
2NF 3NF 4NF
1
3 1
6 4 1
─ 4BS is a good tool to study 3NF effects.
─ stressed by Fonseca.
─ solve Faddeev-Yakubovsky eq. exactly.
─ 4NF effects?
─ First of all, establish 3NF.
─ But look for where?
VNN 20 MeV/pair
V3NF 1 MeV/triplet
V4NF 0.1 MeV/quartet
by J.L. Friar, FBS 22(1997)161.
Results(1) Differential Cross Sections
Faddeev calc (by Prof. H. Kamada) : NN only
(CD-Bonn, AV18, Nijmegen-I,II,93) : NN with TM-3NF : AV18+UrbanaIX-3NF : CD-Bonn+TM’-3NF
Calculations even including 3NF still underestimate the data at cm = 110 – 180 deg.
CC calc (by Honnover group) : CD-Bonn : CD-Bonn+-3NF
Relativistic effects
Hamiltonian of 3N system (total momentum = 0) Relativistic energy
Relativistic NN potential ( in CM system of particle i, j)
Lorentz boosted NN potential into CM system of 3N (Fully relativistic)
Approximations of Vij
• pij <<1• Dependence of k and k’
ji
ijVHH2
10
i
i mmH ])p[( 2/1220
2
2
2
2
41)
21(
)q(
1
,)q'(
1)q'q,(
)q(
1)'kk,(
m
q
m
q
h
hv
hv NR
ijij
22
2/1222/122
2)k(
,]p)k([p])k([
mk
vV
ij
ijijijijijij
ijij
ijij vm
vV2
2
8
p
2222
2
k'
1
k
1
8
p
mv
mvV ij
ijijij
Relativistic prediction
Relativistic kinematical correction
(calc. by Prof. H. Witala) relativistic energy relativistic NN potential
(green line; not fully relativistic) Lorentz boost to 3N c.m. syst
em
(red & pink line) Fully relativistic calculations im
prove the fit to the data only at cm > 160 deg but improvements are not enough. Relativistic 3NF Dirac eq.
Non-Rel.
Rel. NN potential
Lorentz boosted potential
Approx. 1 Approx. 2
There still remains 50% discrepancy!.
X-sec. ratios at 250 MeV & 95 MeV
σ(p+d) /σ(n+d)σ(p+d) /σ(n+d) at at 250250 MeV MeV σ(d+p)/σ(n+d)σ(d+p)/σ(n+d)
at at 9595 MeV / nucleon MeV / nucleon
Coulomb effects ? (too large !)
<4% level by Sauer & Deltuva.
o IUCF, PRC35, 37(87) Sagara, Preliminary
— Hanover (virt. ) Deltuva, PRC67, 034001(03)
— Bochum/Cracow (MEC) Skibinski, PRC67, 054001(03)
— Bochum/Cracow (Sieg.) Skibinski, PRC67, 054001(03)
p+dp+d33He+He+ @ 9 @ 90 MeV/A0 MeV/A
No anomaly observed inpreliminary KVI data!!
KVI, Preliminary Mehmandoost/van Garderen
dd
Ay(d) Ay(N)
Ayy Axx
Axx
present dataAV18AV18+URBIX
●- - -
―
Ayy
present dataAV18AV18+URBIX
●- - -
―
Axx
present dataKVI dataAV18AV18+URBIX
●●
- - -―
Ayy
present dataKVI dataAV18AV18+URBIX
●●
- - -―
Axx ~ Ayy in pd capture
KVI
RCNP
Axx
Ayy
AyyAxx
Ayy & Axx measured
Only Ayy measured