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Possibility of Measurement of Cross Section and Vector Analyzing Powers of p - 3He Breakup Reaction @ Cyclotron Center Bronowice.

IFJ: I. Ciepał, A. Kozela, UJ: T. Pałasz, B. Głowacz, UW: I. Skwira-Chalot, UŚ

Jagiellonian Symposium of Fundamental and Applied Subatomic Physics

3He

Outline:Outline:1. Goals and motivation,2. Theoretical foundation,3. 3NF effects,4. 4N systems – current knowledge,5. Plans for He-3 polarized target at CCB.

Izabela Ciepał, IFJ PANIzabela Ciepał, IFJ PAN

low energies

intermediate energies

50-200 MeV/A

high energies

few-nucleon systems

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intermediate energies

50-200 MeV/A

2N, 3N, 4N

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additional attractive force

3N System Dynamics3N System Dynamics

1957 Fujita-Miyazawa 3NF1957 Fujita-Miyazawa 3NFProg. Theor. Phys. 17, 360 (1957)Prog. Theor. Phys. 17, 360 (1957)

22 -exchange 3NF : -exchange 3NF : - Main ingredients : -isobar excitations in the intermediate

V=∑VNN+V3N

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3N System Dynamics 3N System Dynamics the Three Nucleon Forcethe Three Nucleon Force

➔ Urbana IXUrbana IX -isobar + phenomenological -isobar + phenomenological

short-range part short-range part

➔ Tucson-Melbourne (TM)Tucson-Melbourne (TM) not only not only -isobar , but also -isobar , but also other states arise from other states arise from -N-N scattering; consistent with scattering; consistent with chiral symmetry chiral symmetry

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➢ Few-nucleon interaction models (2N and 3N) Realistic 2N potentials (e.g. Argonn V18, CD Bonn)

+ phenomenological 3NF models Chiral perturbation theory at NNLO (N4LO-2N)  Coupled-channels formalism with explicit Δ                          

                 

Theoretical Background

➢ Faddeev equation can be solved exactly!

numerical results

➢Different effects to be trace

Influences of 3NF Coulomb force action Relativistic effects Mutual interplay of the effects

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➢ Few-nucleon interaction models (2N and 3N) Realistic 2N potentials (e.g. Argonn V18, CD Bonn)

+ phenomenological 3NF models Chiral perturbation theory at NNLO (N4LO-2N)  Coupled-channels formalism with explicit Δ                          

                 

Theoretical Background

➢ Faddeev equation can be solved exactly!

numerical results

➢Different effects to be trace

Influences of 3NF Coulomb force action Relativistic effects Mutual interplay of the effects

CD Bonn relat.

CD Bonn non relat.

ooo

S [MeV]

o

Coulomb effects

Relativistic effects

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Where could we see 3NF effects ?Where could we see 3NF effects ?

➢ Green’s Function Monte CarloGreen’s Function Monte Carlo➢ Ab InitioAb Initio No-Core Shell Model No-Core Shell Model etc..etc..

Ab Initio Calculations for Light Nuclei (A<10)Ab Initio Calculations for Light Nuclei (A<10)

➢3NF : well reproduce the data - 3H, 3He, 4He by 2-exchange 3NF - Illinois-2 ( 2-exchange + 3-ring with -isobar)

➢3NF Effects in B.E. 10 – 25 % attractive

S.C. Pieper PRC 64,014001(2001)

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Where could we see 3NF effects ?

➢ Green’s Function Monte CarloGreen’s Function Monte Carlo➢ Ab InitioAb Initio No-Core Shell Model No-Core Shell Model etc..etc..

Ab Initio Calculations for Light Nuclei (A<10)Ab Initio Calculations for Light Nuclei (A<10)

➢3NF : well reproduce the data - 3H, 3He, 4He by 2-exchange 3NF - Illinois-2 (2-exchange + 3-ring with -isobar)

➢ 3NF Effects in B.E.

10 – 25 % attractive

S.C. Pieper PRC 64,014001(2001)

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3NF3NF Model Model

Discovery of 3NF in 1998

Discrepancy at CS minimum was excellently explained by 23NF.The same 23NF also reproduces 3N binding energy. H.Witala et al., Phys Rev Lett. 81 1183 (1998)

N + d → N + d elastic scattering

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Experiments Experiments

RIKEN

COSY

IUCF

BINA

KVI

RCNP

SALAD

WASA

GEMCCB

BINA@CCB

JAPAN USAEUROPE

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Breakup Reaction

N + d → N + N + N

2N2N + TM99

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relativistic effects are visibleat backward angles, but small

even more problems in case of the breakup

spin observables ….

Elastic Scatteting and Breakup

but in general:theory reproduce the data

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many input and output channels

chance for investigation of isospin dependencies higher sensitivity (than in case of 3N systems) for 3NF role of 4NF

2NF 3NF 4NF

6 4 1

3 1

1 2NF>>3NF>>4NF2NF>>3NF>>4NF

3N

2N= 2/3

Outlook: 4N Systems StudiesOutlook: 4N Systems Studies

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IUCF

d+d elastic scattering @ 241 MeV

KVI - BBS

d+d elastic scattering @ 135 MeV

KVI - BINA

d+d -> d+p+n @ 135 MeV

d+d -> d+p+n @ 160 MeV

QFS cross section compared with pd elastic scattering calculations (A. Deltuva) G. Khatri PhD Thesis → next presentation

4N SYSTEMS – CALC. and EXPERIMENTS4N SYSTEMS – CALC. and EXPERIMENTS

d-d systems

d + d d + d →d + d n + → 3He d + d p + t →A.Deltuva , A.C.Fonseca

Phys. Let. B 742 (2015) 285–289

calculations above the 4N breakup threshold

(10, 12.3 MeV)

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● Cross section ● Vector analyzing powers

A. D

eltuva and A. C

. Fonseca, P

hys. Rev. C

87, 054002, 2013

p-3He systems

'60/'80

calculations above the 4N breakup threshold

4N SYSTEMS – CALC. and EXPERIMENTS4N SYSTEMS – CALC. and EXPERIMENTS

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4N SYSTEMS – CALC. and EXPERIMENTS4N SYSTEMS – CALC. and EXPERIMENTS

T. Katabuchi et al. Review of Scientific Instruments 76, 033503 (2005) Spin-exchange optically pumped polarized 3He target for low-energy charged particle scattering experiments.

T. V. Daniels et al. Phys. Rev. C 82, 034002 (2010) - spin-correlation coef., phase-shifts, p-He elastic scat. @ 2 and 6 MeV.

p-3He systems

measurement with polarized 3He target

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Investigation of 4N systems:• Cross section • Vector analyzing powers

p - He3 p - He3

POLHe-3@ CCBnew facility in Krakow:CyclotronCenterBronowice

3He(p, dp)p3He(p, pp)d

3He(p, ppd)

4N Systems Studies @ CCB4N Systems Studies @ CCB utilize a polarized He-3 target utilize a polarized He-3 target

IFJ: I. Ciepał, A. Kozela, UJ: T. Pałasz, B. Głowacz, UW: I. Skwira-Chalot, UŚ

proton beam70 – 230 MeV

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Rb - optically pumped with circular polarized light, then the Rb electron transfer its polarization to the He-3 nucleus by spin-exchange interaction (collisions)

1) Optical pumping

33He Polarized TargetHe Polarized Target

2) Polarization transfer in collisions

SEOP- Spin Exchange Optical Pumping

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SEOP – Pros & Cons SEOP – Pros & Cons

PRESSURE

SET-UP

POLARIZATION

gas at 0.3 – 3 bartakes a lot of time

magnetic field of a few mT

works at high pressure 3Hebuffer gas (p> 1 bar)

compact set-up given by size of target-cell,operation at target position

long built-up times of 3Henuclear polarization (20 h)

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Critical „Parameters” Critical „Parameters”

1) Shape of the cell, 2) Cell windows – material, size, thickness,3) Luminosity - He-3 pressure,4) Relaxation time – gas depolarization,5) Polarization measurements (NMR), 6) Energy straggling (if glass), 7) Vertex reconstruction – detector.

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NMR CoilGlass Cell

Kapton Window

Target Cell - example Target Cell - example

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emergingparticleswindow

beamwindow

Target Cell - projectTarget Cell - project

Cell: Pyrex2 mm thickL = 100 mmO = 40 mm

Windows: Kapton (supported with graphene ), Ti – now is testing 15x60 mm2

O = 16 mm

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POLHe-3@ CCBPOLHe-3@ CCBp-beam

valves

target chamber with windows;polarized 3He

pumping chamber;3He + Rb

owen

laser light

pick-up coils

Helmholtzcoils

B0

z

xy

B. Głowacz

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POLHe-3@ CCBPOLHe-3@ CCB

p-beam

RbHe3

SEOP

laser light

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TARGET

p-BEAM

Test measurement -scheme:

tedlar bag (He-3/He-4) glass cell (He-3/He-4)

energydetectors Ti-window

shield

TRIGGERS: - OR-left OR OR-right - OR-left AND OR-right

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Test measurement: rates at different angles with KRATTA

DuPont™ Tedlar® polyvinyl fluoride (PVF)

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KRATTA Detector – Energy DetectorKRATTA Detector – Energy Detector

J. Łukasik et al. NIM A 709 (2013) 120–128SiPM

BGO

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Vertex Detector – possible choicesVertex Detector – possible choices

Silicon PS detectorSilicon PS detector PS photodiodesPS photodiodes

Teleskops:65/300/300/5500 um thick double-sided Si-strip detectors

Micro Mesh Gas Detectors- Micro Mesh Gas Detectors- micro pattern gaseous micro pattern gaseous detectors; a readout strip detectors; a readout strip pitch of 250 to 500 umpitch of 250 to 500 um

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Summary

Theoretical calculations exist for dd, p+3He, n+3He for elastic scattering and transfer channels, but still for small energies < 35 MeV

rapid progress in calculations for 4N systems. Experimental studies of p+3He are planned at CCB with the use

of the proton beam at energies of 70 - 230 MeV: elastic scattering and breakup reactions.

Near future: test measurements with polarized 3He and new

target cell.

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THANK YOUFOR

YOUR ATTENTION !

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Vertex Detector – possible choicesVertex Detector – possible choicesMicro Mesh Gas Detectors- Micro Mesh Gas Detectors- micro pattern gaseous micro pattern gaseous detectors; a readout strip detectors; a readout strip pitch of 250 to 500 umpitch of 250 to 500 um

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NMRNMR

The NMR system consists of a series resonance circuit tuned to the proton Larmor frequency:

The frequency is swept throughthe resonance signal leading toa absorption/emission of RFenergy by the spin system.

The signal area of the dynamicsignal is compared to the one of the TE signal:

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M. S

. Ab

delm

o ne m

a nd

H.S

. Sh

e ri f, PR

C 36 , 19 00 (1 98 7) .

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Counting Rates Estimation Counting Rates Estimation He3(p,2p)d @ 100 MeV: [mb/MeV*sr2 ] N/s = [mb/MeV*sr 2] * 20/s= 10 * 20/s = 200/s*sr2 * MeV @155 MeV (40 deg ) N/s=1.88*20/s =37 @85 MeV (42 deg ) N/s=1.32*20/s=24 He3(p,pd)p @ 100 MeV: [mb/MeV*sr2 ] p He3 elastic scattering @ 200 MeV deg

2 deg = 0.03488 raddeg = 0.174 rad

N/s=0.1066/s

√ N / N=6.5 h

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L=4.6 cm, p=2.5 bar, T=20 C

Rbeam=4 mm, J=10 pAL(He3)=2*1028 /cm2 /sL(02)=2.6*1029 /cm2 /sL(Si)=3*1029 /cm2 /s13+15=28

L=5 cm, p=0.9 bar, T=20 C

Rbeam=4 mm, J=10 pAL(He3)=1*1028 /cm /s

L=5 cm, p=100 mbar, T=20 C

Rbeam=4 mm, J=10 pAL(He3)=1*1027 /cm2 /s

2

1)

2)

3)

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Relaxation mechanismsRelaxation mechanisms

Field gradients:

Dipole-dipole interaction: