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Jenny Lee RIKEN , Nishina Center

Studies of Nucleon Correlations using Direct Reactions. Isospin Dependence of Nucleon Correlations (knockout and transfer reactions). Neutron-Proton Correlations (knockout, transfer, quasi-free scattering reactions).

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Jenny Lee RIKEN , Nishina Center

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  1. Studies of Nucleon Correlations using Direct Reactions • Isospin Dependence of Nucleon Correlations (knockout and transfer reactions) • Neutron-Proton Correlations (knockout, transfer, quasi-free scattering reactions) • Di-neutron Correlations (breakup reaction ?) • BCS to BEC Transitions ? (knockout and transfer reaction ??) Jenny Lee RIKEN , Nishina Center

  2. Studies of Nucleon Correlations using Direct Reactions • Neutron-Proton Correlations • Isospin Dependence of Nucleon Correlations 30Ne,36Mg knockout on C at 250 AMeV np-transfer on sd-shell nuclei 34,46Ar(p,d) at 70 AMeV 14O knockout on C & p a 65 AMeV np-knockout on 12C at 200 AMeV Support from Theorists • Di-neutron Correlations Quasi-free scattering, proton beam at 2.8 GeV • BCS to BEC Transitions ? 6He breakup on C & p at 70 AMeV

  3. Isospin Dependence of Nucleon Correlations MSU/ NSCL 09084 (planned in 2014): Comparison of the Neutron Spectroscopic Factors from Transfer and Knockout Reactions at E/A=70 MeV RCNP E390 (planned in 2013): Understanding Nucleon Stripping Reaction Mechanisms from Exotic Nuclei at Intermediate Energy • RIKEN NP1112-SAMURAI06 (submitted  deferred): • Steps to Clarify the Isospin Dependence of Nucleon Correlations RIKEN (performed in Dec 2010): Spectroscopic information towards “Island of Inversion” using knockout reaction with in-beam gamma technique Jenny Lee RIKEN , Nishina Center

  4. Nucleon Correlations Truncated shell model space + effective interactions Greater distribution of nucleons to higher energy configuration Few active orbitals In reality High Occupancy Reduction in Occupancy Short-range, tensor & collective correlations Inert Core Inert Core Probing the nuclear wave function Removing nucleon from occupied orbital  Cross sections (probability)depend on the single-particle occupancy & overlap of many-body wave functions

  5. Spectroscopic Factor (SF) Cross Sections Reaction Model Spectroscopic Factors (expt) Quantify Occupancy Correlation Effects How much ? What is the Isospin Dependence of nucleon correlations? How good the effective interaction in Shell Model can describe the correlations ? SM description is accurate • (e,e’p) – Stable nuclei (near closed shell) • Constant ~30-40% of SF reduction compared to theory • Correlations missing in shell-model interactions Some correlations missing in the interactions ? How about Transfer Reactions ? (e,e’p) reactions L. Lapikas, Nucl. Phys. A553, 297c (1993) Transfer Reactions -- long history ( >50 years)  abundant data, but Problems in SF(expt) !

  6. Experimental SF from Transfer Reactions Well-known problem - optical model potentials - parameters - reaction models • ADWA (consistent set) • Johnson-Soper (JS) Adiabatic Approximation takes care of d-break-up effects • Use global p and n optical potential with standardized parameters (CH89) • Include finite range & non-locality corrections • n-potential : Woods-Saxon shape ro=1.25 & ao=0.65 fm; depth adjusted to reproduce experimental binding energy Consistent SFs for 41Ca Reliable Framework  Systematic Studies SF=1.01± 0.06 SF(SM) = 1.00 TWOFNR, M. Igarashi et al., X.D. Liu et al., Phys Rev. C 69 (2004) 064313 J. Lee et al., Phys. Rev. C75 (2007) 064320

  7. Survey of Spectroscopic Factor (Transfer Reactions) Extend to 88 nuclei (ground-state) : Found 225 relevant papers Re-analyzed (unified model) > 430 data sets  Extracted 88 SF(expt) SF(expt) Benchmark  20 % agreement to theory Ground-state SF(theory) J. Lee, M. B. Tsang et al., Phys. Rev. C75, 064320 (2007) J. Lee, M. B. Tsang et al., Phys. Rev. C79, 054611 (2009) Extend Survey to excited states : Re-analyzed >2,000 data ( >300 papers )  Extracted 565 SF(expt) SF(expt) Z=8-16 Do we understand all the correlations ? M.B. Tsang, J. Lee et al., Phys. Rev. Lett 95, 222501 (2005) SF(theory) M.B. Tsang, J. Lee et al., Phys. Rev. Lett 102, 062501 (2009)

  8. Suppression of SFs in Transfer Reactions CH89 + ro=1.25 fm with minimum assumption  consistent SF(expt) with Shell Model Microscopic Input in Reaction Model  JLM potential & Hartree-Fock (SK20) ro=1.25 fm  HF rms radius Global CH89  JLM + HF densities Constant ~30% reduction in SFs J. Lee et al., Phys. Rev. C 73 , 044608 (2006)

  9. n-rich p-rich Suppression of SFs in Transfer Reactions CH89 JLM+HF ΔS=Sn-Sp Constant ~30% reduction in SFs Different sets of consistent parameters  different normalizations J. Lee et al., Phys. Rev. C 73 , 044608 (2006) • Transfer reactions do not yield absoluteSF ; Systematic approach  relativeSF can be obtained reliably over a wide range of nuclei • Nuclear structure purpose Relative normalized SFs

  10. Isospin Dependence of Nucleon Correlations ΔS=Sn-Sp 34,36,46Ar + p→d + 33,35,45Ar Inverse kinematics at 33MeV/A (e,e p’) Rs = 0.6-0.7 S800 Neutron-rich Proton-rich Transfer Reactions: Weak Isospin Dependence of nucleon correlations Target Chamber J. Lee et al., Phys. Rev. Lett 104, 112701 (2010)

  11. Nucleon Knockout with Fast Beams on 9Be / 12C Target Target High incident energy  Reaction only affects a nucleon at surface 9Be or 12C Reaction Theory: Eikonal & Sudden Approximations Core J. Tostevin et al., J. Phys. G, Part. Phys. 25, 735 (1999) Projectile (fast beam) • Rs = σ(expt)/σ (ES+SM) • One-nucleon knockout -- away from stability • Rs strongly depends on separation energy • More correlation effect - strongly bound valence nucleon A. Gadeet al., Phys. Rev. C 77, 044306 (2008) and reference therein ΔS=Sn-Sp

  12. Isospin Dependence of Shell Occupancies? Q: Isospin Dependence ? Knockout reactions: Yes & Strong A. Gadeet al., Phys. Rev. C 77, 044306 (2008) & reference therein Reduction Factor Transfer reactions: Weak p(34,36,46Ar,d) at 33 A MeV J. Lee et al., Phys. Rev. Lett 104, 112701 (2010) Systematic difference between two probes ! Incompatibility  Incomplete understanding in underlying reaction mechanism MSU/ NSCL 09084 (planned in 2014): Comparison of the Neutron Spectroscopic Factors from Transfer and Knockout Reactions at E/A=70 MeV

  13. Focal Plane Target Chamber S800 NSCL 09084: 34,46Ar(p,d)33,45Arat 70 AMeV Beam from A1900 Same incident energy as knockout reaction  Direct comparison Same SF from transfer at higher energy ? (reliability and applicability of model) 70 AMeV  Very few reliable transfer reaction measurements exist Establishing transfer reactions can be used as spectroscopic tools at reasonably high energy due to the beam intensity and quality (eg at RIKEN, energy degraded beam)

  14. Isospin Dependence of Shell Occupancies? Q: Isospin Dependence ? Knockout reactions: Yes & Strong A. Gadeet al., Phys. Rev. C 77, 044306 (2008) & reference therein Reduction Factor Transfer reactions: Weak p(34,36,46Ar,d) at 33 A MeV J. Lee et al., Phys. Rev. Lett 104, 112701 (2010) Systematic difference between two probes ! Incompatibility  Incomplete understanding in underlying reaction mechanism • Transfer Reaction • Future NSCL 09084: 34,46Ar(p,d) at 70 MeV/A • - same energy as knockout reactions for direct comparison Knockout Reaction ?

  15. Is Strong Dependence Theoretically Explaned ? Dispersive Optical Model (DOM) (elastic-scattering & bound-level data for 40-49Ca) R.J. Charity et al., Phys. Rev. C 76 , 044314 (2007) Self-consistent Green’s Functions + FRPA C. Barbieri & W. H. Dickhoff, arXiv:0901.1920v1 Weak dependence Knockout reactions: Strong Dependence Applicability of Eikonal Model (inert-core approximation) for nucleon removal from deeply bound states ? Weak dependence

  16. Knockout Reaction Mechanism Deeply-bound Weakly-bound Rs=sexp/stheo (d,t) transfer 14O(d,t) 14O(d,t) Intranuclear Cascade Model (INC) Direct KO Multiple scattering/ Evaporation Core excitation C. Louchart, A. Obertelli et al., Phys. Rev. C 83, 011601 (R) (2011) ΔS=Sn-Sp (MeV) ΔS=Sn-Sp (MeV) NSCL, MSU - 14O knockout at 60 AMeV F. Flavigny, A. Obertelli et al., Phys. Rev. Lett 108, 252501 (2012) INC: Significant core-excitation process depletes the one-neutron removal channel GANIL E569S – SPIRAL d(14O,t) 13O at 18 A MeV F. Flavigny, A. Obertelli et al. paper in preparation

  17. Knockout Reaction Mechanism Deeply-bound Weakly-bound (d,t) transfer kinematical cut 14O(d,t) • Lowenergytail : • Inelastic interaction betweencore and target ? • FSI between the neutron and the target ? lowenergytail ΔS=Sn-Sp (MeV) NSCL, MSU - 14O knockout at 60 AMeV F. Flavigny, A. Obertelli et al., Phys. Rev. Lett 108, 252501 (2012) Complete Sets of Data  Detailed Investigation of Nucleon Stripping Mechanisms at Intermediate-energy GANIL E569S – SPIRAL d(14O,t) 13O at 18 A MeV F. Flavigny, A. Obertelli et al. paper in preparation

  18. RCNP E390: Exclusive Measurement I 14O (Z=8) - p-shell spherical nucleus, in reach of ab-initio Calc. Reliable structure input  examine different reaction models Data: 12C( 14O, 13N), 12C( 14O, 13O), 12C( 14O, 12N+p), 12C( 14O, 11C+2p) @ 65 A MeV Goal (i) : Investigate the origin of discrepancies between Spectroscopic Factors extracted from Transfer and Knockout with detection of forward-moving protons  tagging decayed protons (core-excitation) • Measuring core-excitation channels • Justify over-prediction due to inert-core assumption • 12N: 1n-knockout + 1p decay • 11C: 1n-knockout + 2p decay Nucleonremoval Planned in Fall 2013 at RCNP with detection of knocked-out nucleons in one-nucleon removal

  19. RCNP E390: Exclusive Measurement II • “Proton” target – structure-less probe Semi-inclusive Data for loosely-bound neutron in 18C, 19C , 20C (40 A MeV & 81 A MeV) • Simpler reaction mechanism • Sensitive to larger part of wave function Y. Kondo et al, Phys. Rev. C 79, 014602 (2009) A. Ozawa et al, Phys. Rev. C 84, 064315 (2011) • Fully-exclusive Data needed at inter-mediate energy • better understanding & tight control of reaction mechanism • benchmark technique for structure studies •  deeply-bounded nucleon -- determine origin of discrepancy in SF studies Goal (ii) : Study the dynamics of proton-induced deeply-bound nucleon-removal Data: 1H( 14O, 13N), 1H( 14O, 13O), 1H( 14O, 12N+p), 1H( 14O, 11C+2p) @ 65 A MeV Fully Exclusive Measurements with Detection of Knocked-out nucleons and Forward-moving proton Planned in Fall 2013 at RCNP

  20. 12C target : 14O  13O + n neutron energy/angular distribution 14O  13N + p proton energy/angular distribution 14O  12N + n + p evaporation channels 14O  11C + n + 2p evaporation channels CH2target: 14O(p,pn)13O energy/angular distribution 14O(p,2p)13N energy/angular distribution 14O(p,pn+p)12N evaporation channels 14O(p,pn+2p)11C evaporation channels 14O(p,d)13O transfer -- angular distribution 14O(p,p)14O elastic scattering -- angular distribution Proton / Neutron 14° • RCNP E390 γ HeavyResidues Target

  21. RIKEN NP1112-SAMURAI06 (submitted  deferred): • Steps to Clarify the Isospin Dependence of Nucleon Correlations Exclusive Knockout data of 14O on C & proton targets at ~ 250 A MeV Neutron ( up to 10° ) Proton/ Neutron Compete Data Set for Detailed Study of Reaction Mechanism Proton Detector was not ready  Proposal Deferred Target With RCNP E390 at 60 AMeV  necessary for 250AMeV data ? Proton, Heavy Residues SAMURAI

  22. Isospin Dependence of Nucleon Correlations MSU/ NSCL 09084 (planned in 2014): Comparison of the Neutron Spectroscopic Factors from Transfer and Knockout Reactions at E/A=70 MeV RCNP E390 (planned in 2013): Understanding Nucleon Stripping Reaction Mechanisms from Exotic Nuclei at Intermediate Energy • RIKEN NP1112-SAMURAI06 (submitted  deferred): • Steps to Clarify the Isospin Dependence of Nucleon Correlations RIKEN (performed in Dec 2010): Spectroscopic information towards “Island of Inversion” using knockout reaction with in-beam gamma technique Jenny Lee RIKEN , Nishina Center

  23. 32Mg 33Mg 34Mg -1n 31Na 32Na 33Na 25Ne 26Ne 27Ne 28Ne 29Ne 30Ne 31Ne 32Ne N=20 Nuclear Structure in the “Island of Inversion” Island of Inversion -1n Single-neutron Removal 1p3/2 35Mg 36Mg 20 8 2 1f7/2 -1n Magic number 1d3/2 2s1/2 1d5/2 • Energy Level Scheme • Indicate the presence of pf-shell intrude configurations 1p1/2 1p3/2 • Cross Sections • Quantify the intrusion of pf-shell configurations n l j 1s1/2 (36Mg,25Mg + g) (30Ne, 29Ne + g) • Systematic study towards and across the island of inversion: • establish the role of intruder configurations • evaluate the current shell models

  24. RIKEN (performed in Dec 2010): Spectroscopic information towards “Island of Inversion” using knockout reaction with in-beam gamma technique Beams: 30Ne, 36Mg @ ~ 250 A MeV DALI2 (γ-ray detection) ZeroDegree (fragment PID & momentum measurement) Target: Carbon BigRIPS (Beam PID)

  25. Probing Neutron-Proton Correlations RCNP E365 (completed in Jan 2012): Systematic studies of neutron-proton pairing in sd-shell nuclei using (p,3He) and (3He,p) transfer reactions RIKEN NP1206-SAMURAI10 (April 18-19, 2013): Study of Neutron-Proton Correlation & 3N-Force in N=Z nuclei Proposal: Study of Short-range Correlation in nuclei with high energy proton beam Idea: np-knockout using proton target at ~ 400 AMeV ? Jenny Lee RIKEN , Nishina Center

  26. Neutron-Proton Pair Correlations In nuclei: 4 types of Pairs Isovector (T=1, S=0) nn, pp, np pair np should be similar to nn & pp Isoscalar (T=0, S=1) np pair (deuteron-like)  new phase of nuclear matter Theoretical & experimental efforts since 60’s  Contradicting opinions & results ! Isoscalar (T=0) np-pairing A lot of uncertainties !! Isovector (T=1) np-pairing Well defined from the Isospin Symmetry Long-standing open fundamental questions: ○ Nature of T=0 pair in nuclear medium ? ○ Mutual Strength & Interplay of T=0 and T=1 np, nn, pp pairs ? ○ Does T=0 pairing give rise to collective modes ?

  27. 12C – Interesting Physics Found & Hidden 12C + 12C  X + anything@250MeV/u (inclusive) 12C(e,e’pN) @ 4.627 GeV 12C Strong NN tensor force (short-range correlations) R. Subedi et al.,Science 320 (2008) 1476. J.M. Kidd et al., PRC 37, 2613 (1988). 12C(p,3He) ,12C(p,t) @ 40MeV σnp/σ nn~2.4 factor of 18 factor of ~ 8 M. Yasue et al., J. Phys. Soc. Jap. 42, 367 (1977). > p -2p For 12C, 4p & 4n on p3/2 shellNo correlation: factor of 2.67 (pair counting) -np What is the behavior of np-correlations as a function of the relative momentum of the pair ? n n n -2n

  28. Neutron-Proton Removal Reactions R. Schiavilla et al., Phys. Rev. Lett. 98, 132501 (2007) np M. Alvioli et al., Phys. Rev. Lett. 100, 162503 (2008) pp Tensor Interaction – different relative significance to Central at different region 12C: ratio of np/nn cross section Different Reaction Mechanisms  Sensitive to Different range of 2N Correlations • Transfer: ~ 1-2 • HI-induced Knockout : ~8 • (e,e’pn): ~18 Various types of Reaction Mechanisms  Complete Picture of np-tensor Correlations ?

  29. Probing Neutron-Proton Correlations longer-range RCNP E365 (completed in Jan 2012): Systematic studies of neutron-proton pairing in sd-shell nuclei using (p,3He) and (3He,p) transfer reactions RIKEN NP1206-SAMURAI10 (April 18, 2013): Study of Neutron-Proton Correlation & 3N-Force in N=Z nuclei Proposal: Study of Short-range Correlation in nuclei with high energy proton beam short-range

  30. Two-nucleon Transfer Reactions Similarity between pairing field and 2-body transfer operator Two-nucleon transfer reactions like (t,p) or (p,t)  specific tool to probe T=1 pair correlations Spectra from (p,t) reactions Ground-state composed of BCS pairs, two-nucleon transfer cross sections enhanced S.J. Freeman et al. PRC 75 051301(R) (2007) R.A. Broglia et al., Adv. Nucl. Phys. 6, 287 (1973) 76Ge & 76,78Se(p,t) strength: predominately to the ground states  simple BCS paired states Neutron-Proton pairing using np transfer ?

  31. Two-nucleon Transfer Reactions T=0 (T=1) pairing: enhanced transfer probabilities 0+→ 1+(0+→ 0+) levels Interacting Boson Model (IBM-4) Reactions (p, 3He), (3He,p)DT=0,1 (d,a), (a,d)DT=0 (a, 6Li), (6Li,a)DT=0 T=0 stronger T=1 stronger Measure the np transfer cross section to T=1 and T=0 states Absolute σ(T=1) and σ(T=0) – character and strength of the correlations σ(T=1) /σ(T=0) – interplay of T=1 and T=0 pairing modes

  32. Systematics of T=0 & T=1 np-pairing in sd-shell N=Z nuclei in sd-shell Ratio of cross section (T=1/ T=0) - reducing systematic effects of absolute normalization from A. Macchiavelli(LBNL) (3He,p) Shiro Yoshida, NP 33, 685 (1962) Inconsistencies in the trends (sd-shell): • Closed-shell nuclei 16O, 40Ca NOT follow single-particle estimate ? • No intuitive understanding – 20Ne, 24Mg follow single-particle prediction ? • Doubtful increase of > a factor of 10 from 24Mg to 28Si ?

  33. Goals: Insight & quantitative knowledge of T=0 and T=1 np-pairing mechanism • Consistent absolute (dσ/dΩ) + at 0º  Reliable systematics • Systematic measurements spanning sd-shell nuclei under SAME condition – Interplay of T=0 and T=1 np pairing Five reactions proposed: – Individual T=0 & T=1 collectivity 24Mg(3He,p), 32S(3He,p) @ 25 MeV 24Mg(p,3He), 28Si(p,3He) & 40Ca(p,3He) @ 65 MeV • Joint analysis (3He,p) & (p,3He) •  complete understanding – addition & removal transfer reactions for np-pairing Systematic framework -- studies of np pairing in heavier N=Z nuclei (RI Beams)

  34. RCNP E365 (Completed in Jan 2012): Systematic studies of neutron-proton pairing in sd-shell nuclei using (p,3He) and (3He,p) transfer reactions 3H beam at 25 MeV 24Mg(3He,p), 32S(3He,p) Proton beam at 65 MeV 24Mg(p,3He),28Si(p,3He),40Ca(p,3He) LAS Grand Raiden Plastic scintillators(front of FP) Grand Raiden recoil particle Two MWDCs -- position One plastic scintillator -- E, TOF for PID LAS  elastic scattering reaction (beam normalization & target thickness measurement) 65 MeV proton / 25 MeV 3He beams from injector AVF cyclotron (bypass Ring-Cyclotron)

  35. Revisiting (p,3He) and (3He,p) reactions in the sd shell RCNP Experiment – E365 CompletedinJan,2012 24Mg (3He,p) at 25MeV OnlineAnalysis OnlineAnalysis Theoretical analysis of structure by Alex Brown (MSU) and fulltwo-steptransferreactions byIan Thompson (LLNL) Data Analysis On-going

  36. Probing Neutron-Proton Correlations longer-range RCNP E365 (completed in Jan 2012): Systematic studies of neutron-proton pairing in sd-shell nuclei using (p,3He) and (3He,p) transfer reactions RIKEN NP1206-SAMURAI10 (April 18, 2013): Study of Neutron-Proton Correlation & 3N-Force in N=Z nuclei

  37. Two-Nucleon Knockout Model Target Theoretical Cross sections: 9Be/ 12C Reaction: Eikonal & Sudden approximation Structure: 2N Overlap from Shell Model J. Tostevin, B.A. Brown, PRC 74, 064604 (2006) Projectile (fast beam) E.C. Simpson and J. Tostevin et al., PRL 102, 132502 (2009) - 2n knockout from 34Ar, 30S, 26Si 2n or 2p knockout (T=1) K. Yoneda et al., Phys. Rev. C 74 , 021303(R) (2006) D. Bazin et al., Phys. Rev. Lett. 91, 012501 (2003) A. Gade et al., Phys. Rev. C 74 , 021302(R) (2006) P. Fallon et al., PRC 81, 041302(R) (2010) 2N knockout cross sections  carry information of 2N correlations Framework to quantitatively assess descriptions of 2n & 2pT=1 correlations

  38. 12C – Interesting Physics Found & Hidden Advanced Model np removal with T=0 First Calculations : np removal from 12C (with Shell Model Calc. from B.A. Brown) E.C. Simpson and J.A. Tostevin, PRC 83, 014605 (2011). PJT interaction -2n WBP Shell model -2p 10B -np p-shell T=0 np-spatial correlations in the wave functions are insufficient T = 0 cross-sections – sensitive to different effective interactions !

  39. np-Correlations & 3-body Force Structure Model Eikonal-Theory Reaction Model σ(theo) np-removal of 12C on 12C target • Conventional Shell Model B.A. Brown (MSU) Ο NCSM (NN+3N) ∆NCSM (NN, w/o3N) • No-core Shell Model (NCSM) • (realistic 2-body and 3-body forces ) • P. Navratil (TRIUMF) theo. σ-np (mb) 10B ■ Conventional Shell model Significant Increase in the T=0 Cross Sections ! T=0 cross section Sensitive to 3N-force ! E. C. Simpson, P. Navrátil, R. Roth, and J. A. Tostevin Phys. Rev. C 86, 054609 • TOSM (tensor-optimized shell model) T. Myo (Osaka Tech) Final-State-Exclusive Data needed to pin-point the physics !

  40. RIBF: First final-state exclusive measurement of np-pairremoval in 12C (April 18, 2013) 12C  10B (-np), 10C (-2n), 10Be (-2p) @ 200 A MeV γ-residues-neutron Measurement SAMURAI DALI2 • First quantitative study of np-correlation & 3-body force • First detailed study of diffractive mechanism in 2N removal reaction Target • First insight into internal structure of correlated pairs (FSI considered) Benchmark: New Powerful Tool of Direct np-removal reaction SAMURAI at RIBF  Systematic & Quantitative knowledge of np-Correlations & 3N-force toward exotic N=Z nuclei

  41. np-knockout using proton target (or proton beam) at ~ 400 AMeV ? More direct information about np-correlations ! Reaction Mechanism / Cross Sections ? GR (5.66 Tm) SAMURAI LAS (3.2 Tm) SAMURAI  large acceptance  1N and 2N removal channel can be measured simultaneously Proton detectors Neutron detectors

  42. Probing Neutron-Proton Correlations longer-range RCNP E365 (completed in Jan 2012): Systematic studies of neutron-proton pairing in sd-shell nuclei using (p,3He) and (3He,p) transfer reactions RIKEN NP1206-SAMURAI10 (April 18, 2013): Study of Neutron-Proton Correlation & 3N-Force in N=Z nuclei Proposal Study of Short-range Correlation in nuclei with high energy proton beam short-range

  43. What SRC in nuclei can tell us about: High – Momentum Component of the Nuclear Wave Function. SRC ~RN The Strong Short-Range Force Between Nucleons. tensor force, repulsive core, 3N forces LRC ~RA Cold-Dense Nuclear Matter (from deuteron to neutron-stars). Nucleon structure modification in the medium ? EMC and SRC Short Range Correlations in Nuclei 2N-SRC ~1 fm 1.f 1.7f 1.7 fm A~1057 o = 0.16 GeV/fm3 Nucleons

  44. Indication for SRC Spectroscopic factors for (e, e’p) reactions Spectroscopic Factor show only 60-70% of the expected single-particle strength. L. Lapikas, Nucl. Phys. A553, 297c (1993) Benhar et al., Phys. Lett. B 177 (1986) 135. MISSING : Correlations Between Nucleons SRC and LRC

  45. 12C – Interesting Physics found & hidden ~ 18 times > p n n n 12C(e,e’pN) @ Jefferson Lab. (US)

  46. How about using proton beam ? 12C(p,ppN) A variety of incident energies Larger Reaction Cross Sections Proton Target & Radioactive Beam Proton Beams on “radioactive target” Facility with GeVproton beams CSR, Lanzhou Under Discussion … GSI ->FAIR (2018 ?)

  47. IMP Proton beam with:

  48. ~1 fm Kinematics -- High-energy Proton Beams They have Small deBroglie wavelength:  = h/p = hc/pc = 2  0.197 GeV-fm/(2.8 GeV)  0.44 fm. p  p1 SRC ~RN   pf p0 p p n Target nucleus  p2  pn    p We can then compare pn withpfand see if they are roughly “back to back.” From p0, p1, and p2we can deduce, event-by-event what pf and the binding energy of each knocked-out proton is.   

  49. 2 planes of GEM or W.ch. ~1m apart Array : 3 layers of 10x10x200 cm3 scintillators Veto box Beam 32.5o 60o 20o 6 meter 2 meter Array : 3 layers of 10x10x100 cm3 scintillators Array : 3 layers of 10x10x200 cm3 scintillators Total 450 scintillating counters

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