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W. Lynch, Monday T. Otsuka, Wednesday A. Wuosmaa, Thursday T. Aumann, Thursday. The origin of strong proton-neutron correlations revealed in break-up reactions. Mihai Horoi Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA
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W. Lynch, Monday • T. Otsuka, Wednesday • A. Wuosmaa, Thursday • T. Aumann, Thursday The origin of strong proton-neutron correlations revealed in break-up reactions Mihai Horoi Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA Supported by NSF grant PHY-1068217 and DOE grant DF-FC02-09ER41584 UNEDF M. Horoi CMU
Staggering of Ca Isotopes Charge Radii: A Shell Model Approach Valence space: d3/2 , s1/2 , f7/2 , p3/2 E. Caurier et al, PLB 522, 240 (2001) I. Talmi NPA 423, 189 (1984) M. Horoi CMU
Evolution of lowest 0+ and 1+ states in N=Z nuclei Notice the energy scales! M. Horoi CMU
Shell Model Effective Hamiltonians empty valence frozen core PRC 74, 34315 (2006), 78, 064302 (2008) core polarization: Phys.Rep. 261, 125 (1995) M. Horoi CMU
N=Z sd-Nuclei M. Horoi CMU
Decoupling the singlet pn-pairing M. Horoi CMU
Decoupling the singlet pairing M. Horoi CMU
Decoupling the singlet pairing M. Horoi CMU
Spectroscopic Factors One particle removal cross section: e.g. (p,d) e.g. (d,p) Sum rule: s.p. occupation probability M. Horoi CMU
Are SFs (reliable) “observables”? [Jenny Lee et al, PRL 2010] g.s. SFs seem to be more reliable [Gade et al, PRL 93, 042501] M. Horoi CMU
Spectroscopic factors in the pf-shell J. Lee et al. Phys. Rev. C 79, 054601 (2009) B. Tsang et al. Phys. Rev. Lett. 102, 062501 (2009) M. Horoi CMU
Spectroscopic Factors: (d,p) consistent with (p,d) B. Tsang, J. Lee, W. Lynch Phys. Rev. Lett. 95, 222501 (2005) M. Horoi CMU
pf-Nuclei M. Horoi CMU
Spectroscopic Factors: Independent Particle Model (IPM) • IPM Model: • n identical nucleons in • One single j-shell: e.g. f7/2 • Only pairing interaction B. Tsang, J. Lee, W. Lynch Phys. Rev. Lett. 95, 222501 (2005) M. Horoi CMU
Can one measure neutron S7/2 for N=28 isotones? M. Horoi CMU
The Magic of Proton-Neutron Correlations New/MSU 2010/MSU Data from J. Lee and B. Tsang M. Horoi CMU
S7/2 for N=28 isotones and f7/2 n-occupation M. Horoi CMU
S7/2 for N=28 isotones and f7/2 n-occupation M. Horoi CMU
S7/2 for N=28 isotones described in the f7/2 shell f748 int: KUTCHERA et al. NUOVO CIM, VOL-1 NO-12 J T V(JT) Vpn 0 1 -2.068 0.0 1 0 -2.061 0.0 2 1 -0.757 3 0 -0.989 4 1 0.119 5 0 -0.811 6 1 0.333 7 0 -2.218 0.0 M. Horoi CMU
SDPF-U: PRC 79, 014301 (2009) The case of 46Ar ? M. Horoi CMU
Shell Model Effective Hamiltonians empty valence frozen core PRC 74, 34315 (2006), 78, 064302 (2008) core polarization: Phys.Rep. 261, 125 (1995) M. Horoi CMU
SDPF-U + pn “monopole” modifications Occupation probabilities in 46Ar: The case of 46Ar M. Horoi CMU
Summary and Outlook • Spectroscopic factors could be a good tool to identify the enhanced proton-neutron correlations in N~Z nuclei. • Large fluctuations of the neutron SF vs proton number are predicted by the shell model and observed in experiments: strong proton-neutron correlations are essential in nuclei! • These correlations are challenging for mean field theories, but seems to be accommodated by the Green’s function approach! • Parts of the effective H responsible for these strong neutron-proton correlations were identified. • This seems to be just the tip of the iceberg for proton-neutron correlation! More work necessary. M. Horoi CMU
S7/2 for N=28 isotones described in the f7/2 shell f748 int: KUTCHERA et al. NUOVO CIM, VOL-1 NO-12 J T V(JT) Vpn 0 1 -2.068 0.0 1 0 -2.061 0.0 2 1 -0.757 3 0 -0.989 4 1 0.119 5 0 -0.811 6 1 0.333 7 0 -2.218 0.0 IPM M. Horoi CMU
Short Overview • Few more examples of proton-neutron correlations effects in nuclei • Proton-neutron correlations effects observed in transfer reactions • Which pieces of the shell model Hamiltonian seem to be responsible for these effects M. Horoi CMU
pn-pairing vs pp/nn pairing: Why the difference? Experimental positive parity levels M. Horoi CMU
sd-Nuclei M. Horoi CMU
Which pieces of H2 are responsible? The case of S5/2 for N=14 isotones A. Zuker, PRL 90 (2003) M. Horoi CMU
Which pieces of H2 are responsible? The case of S5/2 for N=14 isotones M. Horoi CMU
Proton-Neutron Pairing: A mean field approach ? Staggering of charge radii of Sn isotopes, MH, PRC 50, 2834 (1995) M. Horoi CMU
W. Dickhoff’s talk M. Horoi CMU
Can one measure S7/2 for N=27 isotones? M. Horoi CMU
sd-Nuclei M. Horoi CMU
26Al Spectroscopic Factors vs (H01)pn M. Horoi CMU
26Al Spectroscopic Factors Experimental Data J. Vernotte et al. NPA 571, 1 (1994) M. Horoi CMU
Are SFs (reliable) “observables”? [Jenny Lee et al, PRL 2010] g.s. SFs seem to be more reliable [Gade et al, PRL 93, 042501] M. Horoi CMU
Spectroscopic factors in the pf-shell J. Lee et al. Phys. Rev. C 79, 054601 (2009) B. Tsang et al. Phys. Rev. Lett. 102, 062501 (2009) M. Horoi CMU
Spectroscopic Factors: (d,p) consistent with (p,d) B. Tsang, J. Lee, W. Lynch Phys. Rev. Lett. 95, 222501 (2005) M. Horoi CMU
Evolution of lowest 0+ and 1+ states in N=Z nuclei Notice the energy scales! M. Horoi CMU
Enhanced realization probability of JT=01,10 g.s. for Odd-Odd nuclei M. Horoi CMU
pn-pairing vs pp/nn pairing: Why the difference? Experimental positive parity levels M. Horoi CMU
Spin-triplet vs singlet pn-pairing in 30P Preliminary PLB 430, 203 (1988) M. Horoi CMU
Proton-Neutron Pairing and Binding Energies P. Vogel, nucl-th:9805015 M. Horoi CMU
transfer versus knockout [FN, Deltuva, Hong, PRC submitted 2011] [Jenny Lee et al, PRL 2009] [Gade et al, Phys. Rev. Lett. 93, 042501] M. Horoi CMU
Nuclear Configuration Interaction Center-of-mass spurious states d = 2 (2 j + 1) Nmax pf sd JT-scheme: OXBASH, NuShell J-scheme: NATHAN, NuShellX M-scheme: Oslo-code, Antoine, MFDN, MSHELL, CMichSM, … Limits: 1010 – 1011 m-scheme basis states Lanczos algorithm: provides few lower energies, especially the M-scheme codes. M. Horoi CMU
pf-Nuclei M. Horoi CMU
Spectroscopic Factors: SM vs IPM for N=Z nuclei • IPM: • n identical nucleons in • One single j-shell: e.g. f7/2 • Only pairing interaction 54Co27 50Mn25 B. Tsang, J. Lee, W. Lynch Phys. Rev. Lett. 95, 222501 (2005) M. Horoi CMU
26Al Spectroscopic Factors: SM vs IPM • Model: • n identical nucleons in • One single j-shell: e.g. d5/2 • Only pairing interaction B. Tsang, J. Lee, W. Lynch Phys. Rev. Lett. 95, 222501 (2005) M. Horoi CMU
Staggering of Ca Charge Radii: A Shell Model Approach Valence space: d3/2 , s1/2 , f7/2 , p3/2 E. Caurier et al, PLB 522, 240 (2001) I. Talmi NPA 423, 189 (1984) M. Horoi CMU
sd-nuclei: N=13 odd-odd isotones M. Horoi CMU