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Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

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Page 1: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Systematic Experiments on UnsolvedAnomalies in 3N breakup Reactions

Kenshi Sagara ( Kyushu University)

Page 2: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

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3N bound state

Scattering & reactions

Page 3: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Ay puzzle1986

Ay puzzle

pd CS discrepancy1994-1996-1997

(Sagara discrepancy)

3N BE problem1980’s

3NF(FM)was found

1998

pd breakup discrepancy

pd captureAjj anomaly

3NF?3NF?relativity?

Space Star anomaly1980’s

higher energy discrepancies

pd sactt. discrepancy

lower energy discrepancies

lower energy discrepancies

Off-plane star anomalyQFS anomaly?

???

???

Discrepancies in 3N systems and their origins

FM-3NF1957

Page 4: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

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+

+ +

+

23NF confirmed in BE and CS.Complex discrepancies remain in AP’s.

Axx~Ayy, Axx anomalyNew 3NF at higher energy?

Discrepancies at higher energy

Discrepancies at lower energy

Page 5: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

3H binding energy

(Experiment)

8.482MeV

(Theory)

2NF

~1MeV 23NF?

23NF has an adjustable parameter.

3H binding energy alone is not the evidence of 23NF.

Page 6: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Systematic measurement of pd scattering Ay at Ep =2-18 MeV at KUTL(1994)

Page 7: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

E-dependence of Ay puzzle (1994)

Ay puzzle is not related to 23NF.Ay puzzle is a puzzle still now.

Discrepancy of-10% ~ -40%

Page 8: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Measurement of cross section within 1% accuracy was a hard work.

Energy spectrum of pd scattering

Page 9: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

pd scattering cross section at 2-18 MeV were measured systematically(1994)

Exp. errors < 1%. Data were “well” reproduced by 3N calculation. What is the output from this precise experiments?

Page 10: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

At the cross section minimum, large discrepancy in relative value was found. (Comapred to Approx.CoulombCalculation)

CS discrepancy is comparable to Ay puzzle. But, no one paid attention to this fact !

I appealed this fact to Koike, but Koike did not believe it.

Page 11: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

At RIKEN, pd scattering was measured to construct a d-beam polarimeter.

30% discrepancy at CS minimum was found also at Ed = 270 MeV. Coulomb effects are small.

Koike believe the CS discrepancy.

pd data from SMARTKoike’s nd calculation

N. Sakamoto et al., (1996)

The first contribution from SMART

Page 12: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

By Koike’s talk at Few-Body Conf. at KVI (1997), CS minimum discrepancy was widely recognized.

Page 13: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

H.Witala et al., Phys Rev Lett. 81 1183(1998)

Discrepancy at CS minimum was excellently explained by 23NF.The same 23NF also reproduces 3N binding energy.

Existence of 23NF was confirmed (1998), after 41 years since Fujita-Miyazawa theory (1957).

Page 14: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

23NF boom from1998

Page 15: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

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+

+

+ +

3NF searches started

RIKEN, KVI, RCNP, IUCF, ・・

KUTL, RCNP, KVI

KUTL, RCNP

Page 16: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Ed=140MeV

Ed=200MeV

Ed=270MeV

Ayd Axz Ayy Axx

K. Sekiguchi et al.

Pd scattering CS is well reproduced by including 23NF, but Polarization observables can not be reproduced by 23NF.

Page 17: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Strategy of Kyushu group

Search for new 3NF’s other than 3NF (3NF, 3NF)

in pd capture reaction and pd breakup reaction

+

+

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+ +

Kyushu G experiments (→new 3NF)

Page 18: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

pd capture experiment

+ +

○   Short-range forces may play important roles. (→new 3NF)

×   Reaction cross section is very small (< 1 barn).

Experimental techniques•thick target & low BG   →  liquid hydrogen target •high-efficiency detection → one-shot measurement of whole                     angular distribution

Page 19: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)
Page 20: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Side View(enlargement)

12

Front View

Liquid Hydrogen Target精密実験に不可欠

Page 21: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Vertical planefor Axx

Horizontal planefor Ayy & Ay

(3He) < 4.7

Whole angular distribution was measured in one shot.

Page 22: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)
Page 23: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Y

Data analysis for Axx

Page 24: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Data analysis for Ayy & Ay

Page 25: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

pd capture at Ed = 200 MeV 2 NF2 NF +3 NF

Calc. by Witala et al.

0 50 100 150

0.2

0.0

0.2

0.4

0.6

Axx

C.M angle (deg.)0 50 100 150

0.2

0.0

0.2

0.4

Ayy

C.M angle (deg.)

0 50 100 150

0.2

0.1

0.0

0.1

0.2

Ay

C.M angle (deg.)0 50 100 150

0.5

0.4

0.3

0.2

0.1

Cro

ss 

sect

ion

(m

b/s

r)

0.0

C.M angle (deg.)

Axx anomaly? Axx~Ayy?

Page 26: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Ajj of pd-capture were measured also at KVI, and KVI data agreed with calculations.

Axx Ayy

Azz

● ○    RCNP(200MeV)■ □   KVI  ( 180MeV)

Page 27: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

We made new experiments (present exp.) at RCNP.

Beam : 197 MeV (same as before)Target : Liquid Hydrogen (same as before)Detection: 3He (same as before)

Observables: Axx (same as before) Ayy (same as before) Azz (= -Axx-Ayy) (similar to KVI)

Page 28: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

-0.2

0

0.2

0.4

0.6

0.8

1

0 30 60 90 120 150 180

Azz data

AzzAxxyyAzz126Azz2NFAzz3NFAzzKVI

theta

KVI data at 180 MeV

RCNP data at 196 MeV

Calc. at196 MeV

Page 29: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0 30 60 90 120 150 180

Ayy 137MeV

Ayy137Ayy2NFAyy3NF

theta

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0 30 60 90 120 150 180

Axx 137MeV

Axx137Axx2NFAxx3NF

theta

pd radiative capture at Ed = 137 MeV(multi-II analysis)

Page 30: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Axx   ~   Ayy in pd capture

KVI

RCNP

A xx

Ayy

AyyAxx

Ayy & Axx measured

Only Ayy measured

Page 31: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Why Axx ~ Ayy holds in pd capture?

Is it a signal of new 3NF?

Page 32: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

d-α elastic scattering Ed=15MeV d-3He breakup

Nucl. Phys. A265 280(1976)

Nucl. Phys. A334 365(1980)

Except for pd capture, Axx~ -Ayy holds in general

Ayy

Axx

yyxx AA

Axx Axx

AyyAyy

Page 33: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Ayy < 0

Axx < 0

pd capture reaction

Axx ~ Ayy <0

Ayy > 0

Axx < 0

d-induced reaction in general

Axx ~ -Ayy

Peripheral region ?Axial symmetryCentral region ?Short-range force ?

Page 34: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Ay puzzle1986

Ay puzzle

pd CS discrepancy1994-1996-1997

(Sagara discrepancy)

3N BE problem1980’s

3NF(FM)was found

1998

pd breakup discrepancy

pd captureAjj anomaly

3NF?3NF?relativity?

Space Star anomaly1980’s

higher energy discrepancies

pd sactt. discrepancy

lower energy discrepancies

lower energy discrepancies

Off-plane star anomalyQFS anomaly?

???

???

Discrepancies in 3N systems and their origins

FM-3NF1957

Page 35: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

+ + +

pd breakup experiments

At Ep = 250 MeV to search new 3NF effects

At around Ep = 13 MeV to study Star Anomaly

Page 36: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Ay at 250 MeV

3NF effects relativistic effects

Page 37: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

2NF only2NF+3NF

Non-relativisticRelativistic

K. Hatanaka et al., PRC66 044002(2002)Y. Maeda et al., PRC76 014004(2007)

Cross section at 250 MeV

Page 38: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Cross Section

Cross Section at 250 MeV Cross Section Ratio (Exp/Calc)

Page 39: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Elastic

Break-up

At 250 MeV, BU cross section is ~5 times larger than elastic scattering cross section

Page 40: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

GR

LAS

p - beamLiq D2

Target

CS at 250 MeV Only p1 detected

p1

p2 np1

First experiment

Page 41: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

CS at 250 MeV Only p1 detected

2NF+3NFOnly 2NF

nd calc.by H. Witala

p2 np1

Page 42: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

CS at 250 MeV Only p1 detected

2NF+3NFOnly 2NF

nd calc.by H. Witala

p2 np1

Page 43: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

2NF+3NFOnly 2NF

nd calc.by H. Witala

Ay at 250 MeV Only p1 detected

Page 44: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

detected p1

free

We first investigate discrepancy in cross section

CS at 250 MeVOnly p1 detectedp2 np1

p1 and p2 detected

p2

p1

Page 45: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

ABC

A

C

B

1-dependence at different E1

1

E1

detected p1

free

p2

p1

We selected energy B

Page 46: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

detected p1

free

detected p1

detected p2

Page 47: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

2NF+3NF2NF Calc by H. Kamada

2-dependence with 1 fixed at15 degreeand12 = 180 degree

12-dependencewith 1 and 2 fixed at15 degree and 35 degree

12

1 12

1

Page 48: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

2NF+3NF2NF Calc by H. Kamada

2-dependence with 1 fixed at15 degreeand12 = 180 degree

12-dependencewith 1 and 2 fixed at15 degree and 35 degree

12

1 12

1

Page 49: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

GR

LAS

p - beamLiq D2

Target

p1

p2

CS at 250 MeVp2 np1

p1 and p2 detected

Page 50: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

GRVDC + E scintillator

Momentum accept.:2.5%

• GRとLASの相対角度の最小値は約50o

Unpolarized p-beam

Liq D2

Target

D(p,p1p2)n CS at 250 MeV

p1 and p2 detected

LASVDC + E scintillator

Momentum accept. :2.5%

• GR と LASの相対角度の最小値は約 50o

p2 np1

Page 51: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Liquid D2 target

Page 52: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Previous data were confirmed.  New data were added. 3NF effects

Page 53: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Same data.  Relativistic effects.

Page 54: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Same data.  3NF effects and relativistic effects.

Page 55: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

True+BG

BG

1 =15 degree and 2 =35 degree

Page 56: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Check of the absolute cross section

Page 57: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Calc. by H. Witala3NF effects 2NF+3NFOnly 2NF

Page 58: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Calc. by H. WitalaRelativistic effects RelativisticNon-relativistic

Page 59: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Calculation by H. Witala

3NF effects and relativistic effects

Page 60: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

3NF effects and relativistic effects

Page 61: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

x 5.8

If 3NF effects are artificially 5.8 times increased, experimental CS data are roughly reproduced.

Page 62: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Arb

itra

ry u

nit

Possible enhancement of 3NF at higher energy

Page 63: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Summary

At 250 MeV, pd breakup cross section were measured by First, detecting 1-protons from p+d p+p+n reaction, Second, detecting 2-protons in coincidence.

Large discrepancy of about 2 times in CS was observed.The discrepancy occurs in a wide angular region.

3NF effects are too small (5.8 time) to explain the discrepancy, also relativistic effects are too small to explain the discrepancy.

CS discrepancy monotonically increases with energy. New 3NF may be necessary to explain the discrepancy.

Page 64: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Ay puzzle1986

Ay puzzle

pd CS discrepancy1994-1996-1997

(Sagara discrepancy)

3N BE problem1980’s

3NF(FM)was found

1998

pd breakup discrepancy

pd captureAjj anomaly

3NF?3NF?relativity?

Space Star anomaly1980’s

higher energy discrepancies

pd sactt. discrepancy

lower energy discrepancies

lower energy discrepancies

Off-plane star anomalyQFS anomaly?

???

???

Discrepancies in 3N systems and their origins

FM-3NF1957

Page 65: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)
Page 66: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

The origin of Space Star anomaly

Space Star : configuration of three outgoing nucleons form an equilateral triangle and have the same energy

Blue line : nd calc   Red Line : pd calc  

Space Star

nd : exp > calcp d : exp < calc

calc : coulomb effect is very small

c.m. system

n+d→n+n+p

p+d→p+p+n

Page 67: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Off-Plane Star anomaly

Cross Section reported by Koeln Univ.

Define the angle between Star plane and beam axis, α

α=90°   Space Star

Large anomaly is shown

c.m. system

Ed=19MeV

Page 68: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Off-Plane Star anomaly

Cross Section reported by Koeln Univ.

Define the angle between Star plane and beam axis, α

α=90°   Space Star

Large anomaly is shown

c.m. system

Ed=19MeV

Page 69: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Experiment

Observable : Cross Section

Incident Energy :Ed = 19 MeV

Target : CH2 foil ( rotary target )

Detector : Si-SSD

Set up of scattering chamber

1 2

Page 70: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

T1-T2[ns]

T(E

1)-T

(E2)

[ns]

Break up event

E1  [MeV]

E2

[MeV

]

S curve

11

2212 22

)()(E

mL

E

mLETET pp

mp  :   proton massEi   :   energy of detected protonLi   :   length between target and detector

Remove B.G.

E2

[MeV

]E1  [MeV]

B.G.+ true

E2

[MeV

]

E1  [MeV]

B.G. only

1 2

Page 71: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Ed=19MeV

calc : Mr.Deltuva

Present data

Koeln data

Page 72: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

Only Space Star Anomaly (~90º ) exists.We used an unpolarized beam to carefully measure cross section.

Why Space-Star anomaly appears is the next problem.We will make systematic experiments at perpendicular plane.

Page 73: Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)