低密度原子核体系中的双中子关联现象 孙保元 (Bao Yuan SUN) 兰州大学核科学与技术学院 第十四届全国核结构大会 浙江湖州, 13 April 2012  Introduction  Di-neutron Spatial Correlations in Nuclear Matter 

Slides:



Advertisements
Similar presentations
1 Eta production Resonances, meson couplings Humberto Garcilazo, IPN Mexico Dan-Olof Riska, Helsinki … exotic hadronic matter?
Advertisements

Spectroscopy at the Particle Threshold H. Lenske 1.
微視的核構造反応模型を用いた 9Li 原子核の励起状態の研究
HL-3 May 2006Kernfysica: quarks, nucleonen en kernen1 Outline lecture (HL-3) Structure of nuclei NN potential exchange force Terra incognita in nuclear.
1 Di-Neutron Correlation in Soft Octupole Excitations of Medium-Mass Nuclei near Drip-Line Y. Serizawa and M. Matsuo Niigata Univ.
Lectures in Istanbul Hiroyuki Sagawa, Univeristy of Aizu June 30-July 4, Giant Resonances and Nuclear Equation of States 2. Pairing correlations.
Nucleon Effective Mass in the DBHF 同位旋物理与原子核的相变 CCAST Workshop 2005 年 8 月 19 日- 8 月 21 日 马中玉 中国原子能科学研究院.
Microscopic time-dependent analysis of neutrons transfers at low-energy nuclear reactions with spherical and deformed nuclei V.V. Samarin.
8 He における ダイニュートロン形成と崩 れ 2013/7/27 RCNP 研究会「核子・ハイペロン多体系におけるクラスター現象」 1 Department of Physics, Kyoto University Fumiharu Kobayashi Yoshiko Kanada-En’yo arXiv:
Dineutron formation and breaking in 8 He th Sep. The 22nd European Conference on Few-Body Problems in Physics 1 Department of Physics, Kyoto University.
John Daoutidis October 5 th 2009 Technical University Munich Title Continuum Relativistic Random Phase Approximation in Spherical Nuclei.
第十四届全国核结构大会暨第十次全国核结构专题讨论会 浙江 · 湖州 · Nuclear matter with chiral forces in Brueckner-Hartree-Fock approximation 李增花 复旦大学核科学与技术系(现代物理研究所)
Degree of polarization of  produced in quasielastic charge current neutrino-nucleus scattering Krzysztof M. Graczyk Jaroslaw Nowak Institute of Theoretical.
Shan-Gui Zhou URL: 1.Institute of Theoretical Physics,
Universality in ultra-cold fermionic atom gases. with S. Diehl, H.Gies, J.Pawlowski S. Diehl, H.Gies, J.Pawlowski.
Higher Order Multipole Transition Effects in the Coulomb Dissociation Reactions of Halo Nuclei Dr. Rajesh Kharab Department of Physics, Kurukshetra University,
横田 朗A 、 肥山 詠美子B 、 岡 眞A 東工大理工A、理研仁科セB
Role of tensor force in He and Li isotopes with tensor optimized shell model Hiroshi TOKI RCNP, Osaka Univ. Kiyomi IKEDA RIKEN Atsushi UMEYA RIKEN Takayuki.
Structures of Exotic 131,133 Sn Isotopes for r-process nucleosynthesis Shisheng Zhang 1,2 ( 张时声 ) 1. School of Physics and Nuclear Energy Engineering,
Fragmentation mechanism and enhanced mid-rapidity emission for neutron-rich LCPs Yingxun Zhang( 张英逊 ) 中国原子能科学研究院 Colloborator: Chengshuang Zhou 周承双 (CIAE,GXNU),
XII Nuclear Physics Workshop Maria and Pierre Curie: Nuclear Structure Physics and Low-Energy Reactions, Sept , Kazimierz Dolny, Poland Self-Consistent.
Quantum calculation of vortices in the inner crust of neutron stars R.A. Broglia, E. Vigezzi Milano University and INFN F. Barranco University of Seville.
Pengfei Zhuang Physics Department, Tsinghua University, Beijing
1/23 BCS-BEC crossover in relativistic superfluid Yusuke Nishida (University of Tokyo) with Hiroaki Abuki (Yukawa Institute) ECT*19 May, 2005.
Lianyi He and Pengfei Zhuang Physics Department, Tsinghua U.
Ning Wang 1, Min Liu 1, Xi-Zhen Wu 2, Jie Meng 3 Isospin effect in Weizsaecker-Skyrme mass formula ISPUN14, , Ho Chi Minh City 1 Guangxi Normal.
Systematic study of isovector dipole mode up to A=50 KEK 研究会「原子核・ハドロン物理 : 横断研究会」 KEK, 2007 年 11 月 19 日 -21 日 稲倉恒法 中務孝 矢花一浩 ( 筑波大学 ) ( 理研 ) ( 筑波大学 )
J. Su( 苏军 ) and F.S. Zhang( 张丰收 ) College of Nuclear Science and Technology Beijing Normal University, Beijing, China Tel: ,
1 Proton-neutron pairing by G-matrix in the deformed BCS Soongsil University, Korea Eun Ja Ha Myung-Ki Cheoun.
RCNP.08 Breakup of halo nuclei with Coulomb-corrected eikonal method Y. Suzuki (Niigata) 1.Motivation for breakup reactions 2.Eikonal and adiabatic approximations.
Coupling of (deformed) core and weakly bound neutron M. Kimura (Hokkaido Univ.)
M. Matsuo, PRC73(’06) Matter Calc. Two-particle density.
We construct a relativistic framework which takes into pionic correlations(2p-2h) account seriously from both interests: 1. The role of pions on nuclei.
Anomalous two-neutron transfer in neutron-rich Ni and Sn isotopes studied with continuum QRPA H.Shimoyama, M.Matsuo Niigata University 1 Dynamics and Correlations.
Chong Qi ( 亓冲 ) Dept. of Physics, KTH, Stockholm Abrupt changes in alpha decay systematics as a manifestation of collective nuclear modes 赤峰学院 全国核结构大会.
Unitarity potentials and neutron matter at unitary limit T.T.S. Kuo (Stony Brook) H. Dong (Stony Brook), R. Machleidt (Idaho) Collaborators:
N. Itagaki Yukawa Institute for Theoretical Physics, Kyoto University.
Cluster aspect of light unstable nuclei
Extended Brueckner-Hartree-Fock theory in many body system - Importance of pion in nuclei - Hiroshi Toki (RCNP, KEK) In collaboration.
Three-body force effect on the properties of asymmetric nuclear matter Wei Zuo Institute of Modern Physics, Lanzhou, China.
第十四届全国核结构大会暨第十次全国核结构专题讨论会
Fusion of light halo nuclei
Left-handed Nuclei S. Frauendorf Department of Physics University of Notre Dame, USA IKH, Forschungszentrum Rossendorf Dresden, Germany.
Stationary Josephson effect throughout the BCS-BEC crossover Pierbiagio Pieri (work done with Andrea Spuntarelli and Giancarlo C. Strinati) Dipartimento.
D. Jin JILA, NIST and the University of Colorado $ NIST, NSF Using a Fermi gas to create Bose-Einstein condensates.
北京航空航天大学核物理实验研究介绍 北京航空航天大学 核科学与技术系 2012 年 7 月. 报告内容  北京航空航天大学核物理实验组简介  在 RIBLL1 上的一些实验设想.
Strong tensor correlation in light nuclei with tensor-optimized antisymmetrized molecular dynamics (TOAMD) International symposium on “High-resolution.
Faddeev Calculation for Neutron-Rich Nuclei Eizo Uzu (Tokyo Univ. of Science) Collaborators Masahiro Yamaguchi (RCNP) Hiroyuki Kamada (Kyusyu Inst. Tech.)
Tensor Optimized Few-body Model for s-shell nuclei Kaori Horii, Hiroshi Toki (RCNP, Osaka univ.) Takayuki Myo, (Osaka Institute of Technology) Kiyomi Ikeda.
11 Tensor optimized shell model with bare interaction for light nuclei In collaboration with Hiroshi TOKI RCNP, Osaka Univ. Kiyomi IKEDA RIKEN 19th International.
Satoru Sugimoto Kyoto University 1. Introduction 2. Charge- and parity-projected Hartree-Fock method (a mean field type model) and its application to sub-closed.
The coordinate-space HFB approach for describing weakly-bound deformed nuclei 张一怒 指导老师: 裴俊琛 许甫荣 北京大学 October 17 th, 第十五届全国核物理大会 暨第十届会员代表大会 中国.
Few-Body Models of Light Nuclei The 8th APCTP-BLTP JINR Joint Workshop June 29 – July 4, 2014, Jeju, Korea S. N. Ershov.
Pairing Correlation in neutron-rich nuclei
第9届QCD相变和重离子碰撞物理研讨会,杭州
Active lines of development in microscopic studies of
Nuclear structure far from stability
Deformed relativistic Hartree Bogoliubov model in a Woods-Saxon basis
Hiroshi MASUI Kitami Institute of Technology
Role of Pions in Nuclei and Experimental Characteristics
Introduction Calculations for the N=7 isotones Summary
Kernfysica: quarks, nucleonen en kernen
Medium polarization effects and transfer reactions in halo nuclei
Pions in nuclei and tensor force
The p-wave scattering of spin-polarized Fermi gases in low dimensions
Di-nucleon correlations and soft dipole excitations in exotic nuclei
第十四届核结构会议,2012年4月11-16,湖州师范学院
Zr同位素及同核异能态结构的投影壳模型研究
Constraining the Nuclear Equation of State via Nuclear Structure observables 曹李刚 中科院近物所 第十四届全国核结构大会,湖州,
Department of Physics, Sichuan University
Presentation transcript:

低密度原子核体系中的双中子关联现象 孙保元 (Bao Yuan SUN) 兰州大学核科学与技术学院 第十四届全国核结构大会 浙江湖州, 13 April 2012  Introduction  Di-neutron Spatial Correlations in Nuclear Matter  Di-neutron Spatial Correlations in Giant Halo Nuclei  Summary

Di-neutron Spatial Correlations  Pairing correlations play a crucial role in the fermion systems. J. Bardeen, L. N. Cooper, J. R. Schrieffer, Phys. Rev. 108 (1957) A. Bohr, B. R. Mottelson, D. Pines, Phys. Rev. 110 (1958) 936.  In nuclear physics, it is expected that di-neutron correlations in low-density nuclear systems should be significant.  A large scattering length for the 1 S 0 neutron-neutron interaction G.F.d. Téramond, B. Gabioud, Phys. Rev. C 36 (1987) 691.  A large value of the 1 S 0 pairing gap at low densities M. Baldo, J. Cugmon, A. Lejeune, U. Lombardo, Nucl. Phys. A 515 (1990) 409. T. Takatsuka, R. Tamagaki, Prog. Theor. Phys. Suppl. 112 (1993) 27.  Enhancement of cross sections in two-neutron transfer reactions W. von Oertzen, A. Vitturi, Rep. Prog. Phys. 64 (2001)  Small emission angle between 2n in di-neutron decay A. Spyrou, Z. Kohley, T. Baumann et al., Phys. Rev. Lett. 108 (2012) (2n emission in 16 Be)  Recently, experimental and theoretical progress on halo structure of weakly bound neutron-rich nuclei and possible BCS–BEC crossover of di-neutron pairs at low densities has stimulated lots of interests in di-neutron spatial correlations. I. Tanihata:1985, G. F. Bertsch:1991, J. Meng:1996,1998,2006, J. Dobaczewski:1996 M. Matsuo, Phys. Rev. C 73 (2006) B. Y. Sun, H. Toki and J. Meng, Phys. Lett. B 683 (2010) 134. K. Hagino, H. Sagawa, J. Carbonell, P. Schuck, Phys. Rev. Lett. 99 (2007)

Typical Experimental Evidence of Di-neutron Correlations in Nuclei A three-body model including a strong di-neutron correlation can well reproduce a strong low-lying E(1) distribution observed in 11 Li. T. Nakamura et al., PRL 96 (2006) H. Esbensen et al., PRC 76 (2007) T. Myo et al., PRC 76 (2007) The “di-neutron” configuration of 6 He make the dominant contribution to the cross sections of two-neutron transfer reactions. Yu.Ts. Oganessian et al., PRL 82 (1999) 4996.

Di-neutron Coherence Length in Nuclei In medium or heavy superfluid nuclei: HFB M. Matsuo:2005, N. Pillet:2007, Quite unique and exceptional situation: 11 Li and 6 He K. Hagino: JPG 37 (2010) The small value of coherence length in the surface is essentially determined by the finite size properties of single-particle states in the vicinity of the chemical potential and has very little to do with enhanced pairing correlations in the nuclear surface. spatially compact The minimal value of coherence length in surface is essentially determined by the pairing strength. Cooper pair rms radius, measure of the pairing size: small sized Cooper pairs in the surface K. Hagino et al., Phys. Rev. Lett. 99 (2007) Comment: N. T. Zinner and A. S. Jensen (2008). Reply: K. Hagino et al. (2008). In light halo nuclei:

Motivations and Goals  Study the di-neutron spatial correlations in giant halo nuclei with Relativistic Continuum Hartree–Bogoliubov(RCHB) theory J. Meng et al., Prog. Part. Nucl. Phys. 57 (2006) 470.  Spatial distribution of pairing tensor  Coherence length of neutron Cooper pairs B. Y. Sun, Y. Zhang, J. Meng, in preparation.  Explore the di-neutron correlations in nuclear matter based on microscopic calculation (RMF) with a realistic bare nucleon-nucleon interaction (Bonn-B)  Study BCS-BEC crossover phenomenon at low-density nuclear matter B. Y. Sun, H. Toki and J. Meng, Phys. Lett. B 683, 134 (2010). T. T. Sun, B. Y. Sun, J. Meng, H. Toki, submitted to Phys. Rev. C. Whether further similar cases to 11 Li and 6 He exist in the heavier nuclei on nuclear chart? How does pairing correlations account for the small sized Cooper pairs in the surface? Whether further similar cases to 11 Li and 6 He exist in the heavier nuclei on nuclear chart? How does pairing correlations account for the small sized Cooper pairs in the surface? Prediction for giant halo : N  Zr N>40 66 Ca Meng & Ring, PRL80, 460 (1998) Meng et al., PRC65,041302R (2002) Prediction for giant halo : N  Zr N>40 66 Ca Meng & Ring, PRL80, 460 (1998) Meng et al., PRC65,041302R (2002)

BCS (weak coupling)BEC (strong coupling) crossover The transition takes place continuously: BCS-BEC crossover BCS-BEC Crossover Phenomenon Excitonic semiconductors: D. M. Eagles, Phys. Rev. 186, 456 (1969). Ordinary superconductors: A. J. Leggett, J. Phys. Colloq. 41, 7 (1980). Attractive Fermion gas: P. Nozieres and S. Schmitt-Rink, J. Low Temp. Phys. 59, 195 (1985). Color superconductivity: Y. Nishida and H. Abuki, Phys. Rev. D 72, (2005). Nuclear matter: M. Matsuo: PRC2006; J. Margueron: PRC2007; B. Y. Sun: PLB2010.  Weakly interacting fermions  Correlation in p space  Large coherence length  Bosonic bound state  Correlation in r space  Small coherence length

BCS (weak coupling)BEC (strong coupling) crossover The transition takes place continuously: BCS-BEC crossover BCS-BEC Crossover Phenomenon  Weakly interacting fermions  Correlation in p space  Large coherence length  Bosonic bound state  Correlation in r space  Small coherence length Excitonic semiconductors: D. M. Eagles, Phys. Rev. 186, 456 (1969). Ordinary superconductors: A. J. Leggett, J. Phys. Colloq. 41, 7 (1980). Attractive Fermion gas: P. Nozieres and S. Schmitt-Rink, J. Low Temp. Phys. 59, 195 (1985). Color superconductivity: Y. Nishida and H. Abuki, Phys. Rev. D 72, (2005). Nuclear matter: M. Matsuo: PRC2006; J. Margueron: PRC2007; B. Y. Sun: PLB2010.

BCS Approximation and Pairing Gap Equation

Cooper Pair Wave Function in Nuclear Matter Cooper pair wave function BCS Crossover As the density decreases, the spatial structure evolves continuously from BCS-type to BEC-type.  BCS-type: oscillating attenuation  BEC-type: compact, no oscillation Proper treatment of the short-range repulsion of nuclear force leads to suppressed amplitude around r = 0 As the density decreases, the spatial structure evolves continuously from BCS-type to BEC-type.  BCS-type: oscillating attenuation  BEC-type: compact, no oscillation Proper treatment of the short-range repulsion of nuclear force leads to suppressed amplitude around r = 0 The relativistic pairing theory  ph: RMF with PK1 W. Long (2004)  pp: Realistic bare NN force Bonn-B The relativistic pairing theory  ph: RMF with PK1 W. Long (2004)  pp: Realistic bare NN force Bonn-B B. Y. Sun, H. Toki and J. Meng, Phys. Lett. B 683, 134 (2010).

S=0 Probability Density of Neutron Pairs in Nuclear Matter K. Hagino et al., PRL 99(2007) B. Y. Sun, H. Toki and J. Meng, PLB 683(2010)134 A two-dimensional plot for the probability density r 2 |Ψ pair (r)| 2 of the neutron Cooper pair as a function of the relative distance r between the pair partners and the neutron Fermi momentum k Fn in SNM.

BCS-BEC Crossover in Nuclear Matter BCS-BEC crossover region: 0.05 fm -1 < k Fn < 0.7 (0.75) fm -1 for the symmetric (neutron) nuclear matter BCS-BEC crossover region: 0.05 fm -1 < k Fn < 0.7 (0.75) fm -1 for the symmetric (neutron) nuclear matter B. Y. Sun, H. Toki and J. Meng, PLB 683(’10)134 The coherence length in infinite NM strongly depends on the pairing strength and approximate inverse proportionality between the gap and the coherence length could be established. No evidence for the appearance of a true BEC bound state of neutron pairing at any density Coherence Length:

Relativistic Continuum Hartree Bogoliubov Theory  Bogoliubov Transformation:  Quasi-particle Wave Function:  Relativistic Hartree-Bogoliubov Equations: effective interaction NLSH  Pairing Force: V 0 = −670 MeV fm 3 J. Meng, H. Toki, S.G. Zhou et al., Prog. Part. Nucl. Phys. 57 (2006) 470.

To grasp the full physics of nuclear pairing it is very important to work in a large configuration space, comprising several shells below and above the Fermi surface. Probability Density Distribution of Cooper Pairs: |κ(r, R)| 2 r 2 R 2 Different Parity NLSH R m = 5.20 fm R n = 5.47 fm R p = 4.51 fm Contrasted with infinite matter: Different number of levels in the range of the gap value Coulomb barrier: low-j levels

WF: Similarity to BCS-BEC Crossover Phenomenon

Effects of the Parity Mixing The parity mixing induced by the pairing force leads to a short range di-neutron space correlations in the surface of the nuclei. The concentration only shows up when even and odd parity states are mixed. Same conclusion in: F. Catara:1984, L. Ferreira:1984, Tischler:1998, N. Pillet:2007. The strong concentration of small sized pairs in the surface of nuclei can be treated as a feature of halo nuclei.

Influence of the Strength of Pairing Force V 0 = −670 MeV fm 3 V 0 = −460 MeV fm Whether concentration of small sized pairs in the surface is due to pairing correlation? Pairing Energy In giant halo nucleus 134 Zr: The small coherence length of Cooper pairs in the surface of nuclei is essentially determined by the pairing strength. In giant halo nucleus 134 Zr: The small coherence length of Cooper pairs in the surface of nuclei is essentially determined by the pairing strength.

Evolution in Zr Isotope

The di-neutron spatial correlations is studied in both nuclear matter and giant halo nuclei with the relativistic bogoliubov theory. Summary Di-neutron spatial correlations in superfluid nuclei  Similar cases to 11 Li and 6 He exist in the heavier nuclei.  BCS-BEC crossover phenomenon is displayed by WF of Cooper pairs.  Parity mixing in large configuration space leads to a strong concentration of small sized Cooper pairs in the nuclear surface. Low-j level is important!  Pairing correlations have effects on small sized pairs in the surface: 134 Zr.  Evolution of pairing in Zr isotope:possible criterion of BCS-BEC crossover Di-neutron spatial correlations in nuclear matter  A strong concentration of the probability density is revealed for the neutron pairs in the fairly small relative distance.  BCS-BEC crossover region: 0.05 fm -1 < k Fn < 0.7 (0.75) fm -1  The coherence length of Cooper pairs in infinite nuclear matter strongly depends on the intensity of pairing correlations. Thank you for your attention !

北京大学物理学院: 孟杰 教授 孙亭亭 博士 张颖 博士 Collaborators 大阪大学 RCNP : Hiroshi Toki 教授