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For Nuclear Matter� Phys Hadron-Quark Transition in High ! Density Nuclear Matter ! Short Range Dynamics of Nuclear Forces! Probing Nucleon-Nucleon Interactions at < 1fm! and their influence on the nuclear structure ! at short distances.! - Intermediate – short distance tensor forces - Isospin dependence of the tensor forces - NN repulsive core - Hadron-quark transition in the core - non-nucleonic components, hidden color, gluons Introduction to Nuclear Forces ! - 1904 Plum pudding model! J.J. Thompson - 1911 Discovery of Atomic Nuclei! E. Rutherford, Philosophical Magazine Series 6, Vol .21, 1911 “…such large deflexion can not be made of large number of small deviaons…. ….. deflexion is due to single atomic encounter……” - 1913 Rutherford-Bohr model of Atom! 8 Size of the atom: 10− cm ⇠ 13 Size of the nucleus: 10− cm ⇠ Mass of the atom: 99.98% from the nucleus Introduction to Nuclear Forces ! - 1919 discovery of proton! E. Rutherford - 1931 discovery of deuterium! H. Urey - 1932 Discovery of neutron! J. Chadwick - 1932 pn model of the nucleus:! W.Heisenberg, D.D. Iwanenko Nuclear Physics from the properFes of N-N interacFon - 1939 Quadrupole moment of the deuteron:! Kellogg, Rabi, Ramsey, Zakharias 13 - range of the NN force 10− cm ⇠ - intensity of interaction 1500 times of electromagnetic ⇠ - strong dependence on spin orientation Constructing NN Potentials! V 2N V c V l2L2 V tS V lsL · S vls2 L · S 2 e2 R = + + 12 + + ( ) Vcoul = 4⇡r - NN force is attractive: Nuclei are Stable! “If the two-body forces are everywhere attractive and if many-body forces are neglected then the nucleon pairs are sufficiently close to take advantaged of attractive interactions and a collapsed state of nuclear matter results “ ! G. Breit and E.P. Wigner, Phys. Rev. 53, 998 (1938). Jastrow 1951 assumed the existence of the infinite hard core to explain the angular distribution of pp cross section at 340 MeV (r0=0.6fm)! Non-monotonic NN central potential with the repulsive core was introduced: ! Brueckner & Watson 1953 to obtain nuclear density saturation. Modern NN Potentials! 2N 2N 2N 2N V = VEM + Vπ + VR 2N c l2 2 t ls ls2 2 VR = V + V L + V S12 + V L · S + v (L · S) i V = Vint,R + Vcore −1 r−r0 V = 1+e a core ! " 60’s Hans Bethe 1961: More intellectual energy is spent on nuclear physics than on all other issues taken together during enFre human history. VNN,MeV 15 000 10 000 5000 0.2 0.4 0.6 0.8 r,Fm Nuclear Forces and Field Theory! - 1935 meson exchange model: ! H. Yukawa - Predicted meson with around 150 MeV : ! - 1947 meson discovered: ! C.F. Powel - 1943-1945 – most probably seen by:! Artem Alikhanian ⇡+ µ+ + ⌫ Aragats Cosmic Ray Staon ! µ Field Theory of Nucleons & Mesons 1947-! Pomeranchuk, Landau - 1950's 2 2 ↵em(µ ) ↵em(Q )= 2 2 1 ↵em(µ ) ln Q − 3⇡ µ2 3⇡ 277 Q = m e 2↵ 10 GeV e ⇠ Infinite interacFon occurs at transferred momenta approx 500 MeV/c or at internucleon distances 1~Fm. It seems we have a problem about which Nature is not aware of Y.Pomeranchuk All formal quantum field theories with Yukawa type interacFons contain the problem of the ``Zero Charge'’ Pomeranchuk, Sudakov, Ter-MarFrosyan, Phys. Rev. 1956 Phenomenological One-Boson-Exchange Models! Quantum Chromodynamics! M. Gell-Mann - 1973 QCD was established as Yang-Mills theory:! H. Fritzcsh H. Leutwhiller Quantum Chromodynamics! QCD: Asymptotic Freedom ! D.Gross D. Politzer - 1973 Coupling constant renormalization:! F.Wilczek 2 2 α(M ) αs(Q )= 11− 2 2 3 Nf 2 Q 1+ 4π αs(M )ln M 2 2 2 ↵em(µ ) ↵em(Q )= 2 2 1 ↵em(µ ) ln Q − 3⇡ µ2 NN Interaction in QCD: Pauli Blocking! 15 000 Pauli Blocking 10 000 5000 0.2 0.4 0.6 0.8 Contradicts Neutron Star Observations: ! will predict masses not more than 0.1 - 0.6 Solar mass ! NN Interaction in QCD: Lattice Calculation! 600 100 1 3S0 500 S1 50 OPEP 400 300 0 (r) [MeV] 200 C V 100 -50 0.0 0.5 1.0 1.5 2.0 0 0.0 0.5 1.0 1.5 2.0 r [fm] NN Interaction in QCD: Effective Theories! k 1 M ⌧ NN Interaction in QCD: Perturbative QCD! Hidden Color! Vc, MeV 15 000 Intrinsic strangeness/charm! 10 000 5000 0.2 0.4 0.6 0.8 r 6q 1 4 4 T =0,S=1 = 9 NN + 45 ∆∆ + 5 CC q q q ~80% hidden color Harvey 76, …. Brodsky,Ji, Lepage, PRL 83 6q 1 4 4 T =0,S=1 = 9 NN + 45 ∆∆ + 5 CC q q q CC ⌘ NC NC The NN core can be due to the orthogonality of ! =0 h Nc,Nc | N,N i II. From NN Interaction to Nuclear & Nuclear Matter Structure! “Standard” Nuclear Physics Approach A-body Schroedinger equation interacting through NN -potential 2 1 ri + V (x x ) (x , ,x )=E (x , ,x ) 2− 2m 2 i − j 3 1 ··· A 1 ··· A i i,j X X 4 5 2 rN V (x) (x)=E (x) − 2m − HF N N N h i Hartree-Fock potential will smear out main properties NN potential 1990s Asymptotics of high momentum component of nuclear ! A -start with A-body Schroedinger equation interacting through NN -potential 2 1 r i + V (x x ) (x , ,x )=E (x , ,x ) 2− 2m 2 i − j 3 1 ··· A 1 ··· A i i,j X X 4 5 3 1 V (q)φ (k , ,k q, ,k +q, ,k ) d q 2 ij A 1 i j A (2⇡)3 − i=j ··· − ··· ··· φ (k , k , k )= 6 A 1 n A R P A k2 ··· ··· i 2m EB i=1 N − P p2 k = p, EB, ki q = p q 0 q p, k + q k + p 0 k k p 2m − − ⇡ ! ⇡ j ⇡ j ⇡ ! i ⇡ j ⇡ (1) VNN(p) φ (k1, ,ki = p, ,kj p, ,kA) 2 f(k1, 0 0 ) A ··· ··· ⇡ ··· ⇠ p ··· ··· ··· Amado, 1976 (2) 1 VNN(q)VNN(p) 3 φA ( p, ) p2 (p q)2 d q ··· ··· ⇠ − R n -- IF: VNN = q− with n>1 and is finite range qmin (2) V (p) 1 dq φA ( p, ) p2 qn ··· ··· ⇠ qmin R (2) (1) φA φA Frankfurt, Strikman 1988 ⌧ Frankfurt, MS, Strikman 2008 Yerevan Physics InsFtute 4 GeV Jefferson Lab 6 GeV Brookhaven Naonal Lab, 15 GeV 1. Short-Range Correlations in Nuclei ! -- The same is true for relativistic equations as:! Bethe-Salpeter or Weinberg Infinite Momentum Frame equations (1) VNN(p) -- From φ (k1, ,ki = p, ,kj p, ,kA) 2 f(k1, 0 0 ) follows A ··· ··· ⇡ ··· ⇠ p ··· ··· ··· for large k>kF ermi Frankfurt, Strikman Phys. nA(k) aNN(A)nNN(k) Rep, 1988 ⇡ Day,Frankfurt, Strikman, MS, Phys. Rev. C 1993 Egiyan et al, 2002,2006 - Experimental observations Fomin et al, 2011 Day, Frankfurt, MS, Strikman, PRC 1993 Egiyan, et al PRC 2004 6 3He 12C 3 0 /2) 6 D 4 63 He Cu /A)/( 3 A ( 0 6 9Be 197Au 3 0 0.8 1 1.2 1.4 1.6 1.8 1 1.2 1.4 1.6 1.8 2 x x Fomin et al PRL 2011 Day, Frankfurt, MS, Frankfurt, MS, Strikman, 1. Extraction of a2(A,Z) for wide range of Nuclei ! Strikman, PRC 1993 IJMP A 2008 Fomin et al PRL 2011 a2’s as relave probability of 2N SRCs Table 1: The results for a2(A, y) A y This Work Frankfurt et al Egiyan et al Famin et al 3He 0.33 2.07 0.08 1.7 0.3 2.13 0.04 4He 0 3.51±0.03 3.3±0.5 3.38 0.2 3.60±0.10 9Be 0.11 3.92±0.03± ± 3.91±0.12 12C 0 4.19±0.02 5.0 0.5 4.32 0.4 4.75±0.16 27Al 0.037 4.50±0.12 5.3±0.6 ± ± 56Fe 0.071 4.95±0.07 5.6±0.9 4.99 0.5 64Cu 0.094 5.02±0.04± ± 5.21 0.20 197Au 0.198 4.56±0.03 4.8 0.7 5.16±0.22 ± ± ± 2. Dominance of the (pn) component of SRC for large k>k n (k) a (A)n (k) F ermi A ⇡ NN NN TheoreFcal analysis of BNL Data E. Piasetzky, MS, L. Frankfurt, M. Strikman,J.Watson PRL , 2006 P =0.056 0.018 Direct Measurement at JLab R.Subdei, et al Science , 2008 pp/pn ± 102 pn pp/np from [12C(e,e’pp) /12C(e,e’pn) ] /2 pp/2N from [12C(e,e’pp) /12C(e,e’p) ] /2 Factor of 20! np/2N from 12C(e,e’pn) /12C(e,e’p) 12 12 10 np/2N from C(p,2pn) / C(p,2p) SRC Pair Fraction (%) pp Expected 4! (Wigner counting)! 0.3 0.4 0.5 0.6 Missing Momentum [GeV/c] Theoretical Interpretation (1) VNN(p) φ (k1, ,ki = p, ,kj p, ,kA) 2 f(k1, 0 0 ) A ··· ··· ⇡ ··· ⇠ p ··· ··· ··· n (k) a (A)n (k) A ⇡ NN NN 150 V, MeV 100 Vc 50 0 -50 -100 VT -150 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 r,fm Explana'on lies in the dominance of the tensor part in the NN interacon V (r) V ( r)+V (r) S (r)+V L S NN ≈ c t · 12 LS · S12 = 3(σ1 rˆ)(σ2 rˆ) σ1σ2 S12 pp =0 | · · − Isospin 1 states M.S, Abrahamyan, Frankfurt,Strikman PRC,2005 S12 nn =0 S |pn =0 12| S pn =0Isospin 0 states 12| ⇥ 3He Explana'on lies in the dominance of the tensor part in the NN interacon V (r) V ( r)+V (r) S (r)+V L S NN ≈ c t · 12 LS · S12 = 3(σ1 rˆ)(σ2 rˆ) σ1σ2 S12 pp =0 | · · − Isospin 1 states Sciavilla, Wiringa, Pieper, Carlson PRL,2007 S12 nn =0 S |pn =0 5 12 10 4 AV18/UIX He | 4 104 AV6’ He S12 pn =0Isospin 0 states AV4’ 4He ) 6 3 | ⇥ 10 AV18 2H 102 (q,Q=0) (fm 1 NN 10 100 10-1 012345 q (fm-1) - Dominance of pn short range correlations! as compared to pp and nn SRCS ! 2006-2008s! - Dominance of NN Tensor as compared ! to the NN Central Forces at <= 1fm! 2011- present! - Two New Properties of High Momentum Component! - Energetic Protons in Neutron Rich Nuclei ! 3.
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