Nuclear Structure
NUPECC Meeting
Sevilla, October 5th, 2012
Xavier Viñas Gausí
University of Barcelona
UCA
USAL
UB
IEM-CSIC
UAM
UIB
UCM
IFIC-UV
UHU
USE
UGR
UMU
NUCLEAR STRUCTURE
Universidad Autónoma de Madrid
Universidad Complutense. Madrid.
Instituto de Estructura de la Materia CSIC, Madrid
Universidad de Sevilla
Universidad de Huelva
Universitat de Barcelona
Universidad de Cantabria
Universidad de Granada
Nuclear Structure
RESEARCH TOPICS:
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Algebraic models & phase transitions
Chaos in nuclei
Large shell model calculations
RPA & correlations
Relativistic Mean Field
Self-consistent (deformed) mean field and beyond
Few-body systems
Shape coexistence, …
Microscopic calculations in nuclear matter
Symmetry energy
Nuclear Astrophysics
Electron scattering
SUMMARY
Nuclear Structure and Reactions:
UAM, IEM, UCM, USE, UGR, UCA, UB,…
Hadronic/Intermediate Energies:
USAL, IFIC-UV, UGR, UB, UCM, USE,…
Close collaboration with experimental facilities and groups: BNL, RHIC,
JLAB, KEK, Daphne-Frascati, MAMI-Mainz, ELSA-Bonn, GSI-FAIR, etc.
•12 Research Groups: ~60 staff researchers + ~40-50 (RyC, JdC,…) +
PhD students
•9 PhD Thesis (2010/11) [UB, IEM-CSIC, UCM, UGR, USE]
GRUPO FÍSICA NUCLEAR TEÓRICA
IEM-CSIC, MADRID
Sistemas de tres cuerpos en el continuo: Estructura y reacciones
(E. Garrido, R. de Diego, C. Romero)
 Resonancias y modos de desintegración
 Resolución de las ecuaciones de Faddeev en el espacio de coordenadas
 Aplicación del método de rotación compleja para obtener simultáneamente los estados
ligados y las resonancias del sistema
PRC 79 (2009) 054009, PLB 684 (2010) 132, PRC 82 (2010) 034001
 Reacciones a muy baja energía
 Desarrollo de relaciones integrales para extraer la matriz S de la reacción a partir de la
parte interna de la función de onda
 Aplicación a átomos ultrafríos
PRL 103 (2009) 090402, PRC 81 (2010) 034002, PRA 83 (2011) 022705
 Procesos de captura radiativa
 Aplicación de las técnicas de tres cuerpos al estudio de reacciones de interés astrofísico
 Reacción triple alfa y tasa de producción de 12C en el medio estelar
JPG 37 (2010) 064027, EPL 90 (2010) 52001, JPG 37 (2010) 115105, EPJA 47 (2011) 102
FNT – IEM – CSIC – Madrid (P. Sarriguren)
Electroweak Processes in Nuclei
(+ UCM: E. Moya, J.M. Udías, O. Moreno)
JPG37, 064019 (2010); PRC81, 041303(R) (2010); PRC81, 064314 (2011);
PRC83, 025801 (2011); PRC84, 054311 (2011); PRC84, 034316 (2011);
NIMA 637, 60 (2011); PRC85, 064319 (2012)
• Electron scattering from exotic nuclei
• Parity violating electron scattering (Neutron distributions. Neutron skins)
• Beta decay and GT strength (Nuclear Structure: Nuclear deformation;
Astrophysics: Weak decay rates for r, rp processes; Particle Physics: Double
beta decay)
Structural evolution from Gogny-HFB calculations
(+ UAM: L.M. Robledo; + Rice Univ. Texas: R. Rodríguez-Guzmán)
PRC81, 024310 (2010); PLB691, 202 (2010); PRC82, 044318 (2010); PRC82, 061302(R) (2010);
PRC83, 014309 (2011); PRC83, 044307 (2011); PRC83, 054303 (2011); PRC84, 054316 (2011);
PRL108, 062701 (2012); PRC86, 014321 (2012)
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Microscopic justification of critical point E(5) and X(5) symmetries
Onset of nuclear deformation (Axial and triaxial shapes)
Experimental signatures of shape transitions
Mappings to IBM Hamiltonians
GRUPO FÍSICA NUCLEAR
UNIVERSIDAD COMPLUTENSE MADRID
Nuclear Physics Group GFN-UCM
(Complutense University Madrid)
Members:
Permanent: JMG Gómez, E. Moya de Guerra, J. Retamosa, J.M.
Udías, MC Martínez, E. Faleiro, R. Álvarez-Rodríguez (UPM based)
Postdocs: C. Fernández-Ramírez (JdlC), A. Relaño (Lecturer), L.
Muñoz (Assistant Lecturer), O. Moreno (Assistant Lecturer), M. Ivanov
(Visiting scientist)
Main Collaborations:
IEM-CSIC, MIT, Torino, JLab, Mainz, Sofia
UNIVERSIDAD COMPLUTENSE MADRID
•Gamow-Teller strength distributions
and beta+ half-lives in the lead region.
•Two-neutrino double-beta decay
matrix elements.
•Parity-violation asymmetry in electronnucleus scattering and its relation to
neutron distribution (PREX exp.).
•Analysis of beta-decay electron
spectrum in a search for keV sterile
neutrinos as dark matter candidates
(MARE & KATRIN exp.).
•Nuclear structure studies with the
(e,e’p) reaction: spectroscopic factors in
16O ,208Pb, 12C, 207Tl.
•Nuclear structure effects in neutrinonucleus reactions
Power spectrum of nuclear levels with missing levels and mixed symmetries
Obtain Power spectrum
Measure fluctuations
RMT result
1/f noise
Uncorrelated levels
1/f2 noise
If our spectra are incomplete or we mix symmetries we have something in between 1/f and 1/f2
J=3 and J=4 states mixed (full circles) and
non-mixed (open circles)
0.8 fraction of all J=0-8 states
mixed (full circles) and non-mixed (open circles)
Examples with shell model results for 24Mg:
We can fit the fraction of missing levels and the number of mixed symmetries
R.A. Molina, J. Retamosa, L. Muñoz, A. Relaño, E. Faleiro, Phys. Lett. B 644, 25 (2007)
GRUPO FÍSICA NUCLEAR
UNIVERSIDAD AUTÓNOMA MADRID
Theoretical highlights
•Collective nuclei motion (superdeformation, superfluidity, etc.)
•Structure of exotic nuclei and weak interactions
•Neutrinoless double beta decay
Island of inversion around 64Cr
significant computational advance—
S. M. Lenzi, F. Nowacki, A. Poves, and K. Sieja
Phys. Rev. C 82, 054301 (2010)
involving matrix dimensions reaching ten
billion—in shell-model calculations.
Self-consistent mean field and beyond
•Nuclear properties described with an “universal” density-dependent force
and state of the art beyond mean-field calculations
•Configuration mixing techniques & symmetry restored wave functions
•Applications: subshell closures, shape coexistence, transition
probabilities, etc.
GRUPO FÍSICA NUCLEAR BÁSICA
UNIVERSIDAD DE SEVILLA
GRUPO ESTRUCTURA NUCLEAR
Phase transitions in quantum many-body systems within algebraic models:
Given two hamiltonians H1 and H2 that describe different system structures, a transitional hamiltonian can be
constructed as H = x H1 + (1-x) H2
A QPT occurs at some critical value of the control parameter x that controls the relative weight of H1 and H2
Algebraic models are very well suited to study such hamiltonians since in that case H1 and H2 correspond to
different dynamical symmetries.
QPT's in boson, fermion and mixed systems can be studied.
TOPICS (2011)
Nuclei (collaboration with Padova and Huelva):
- odd-even nuclei and critical point symmetries within IBFA.
- effect of three-body terms within the IBA.
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Molecules (collaboration with Huelva):
- finite size N effects in molecular systems within the vibron model.
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Lipkin model (collaboration with Huelva and CSIC Madrid):
- phase transitions in excited states and its connection with quantum
decoherence.
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Dicke model (collaboration with CSIC Madrid, Huelva and Prague):
- phase transitions in excited states and the connection with quantum chaos.
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P. Pérez-Fernández et al. Phys. Rev. E 83. 2011, 046208; Phys. Rev. A2011, 062125; J. Phys. Conf. Ser. 284. 2011, 012049.
L. Fortunato et al., Int. J. Mod. Phys. 20. 2011, 207;J. Barea Muñoz et al., Phys. Rev. C83. 2011, 024307; L. Fortunato et al., Phys. Rev. C84,
2011, 014326; P. Pérez-Fernández et al., Phys. Rev. A83, 2011, 033802
GRUPO ESTRUCTURA MATERIA
UNIVERSIDAD DE HUELVA
1. Estudio de la coexistencia de
forma en el Pt.
J.E. García-Ramos, V. Hellemans
y K. Heyde, PRC 84, 014331
(2011).
2. Triaxialidad en el IBM usando una interacción quadupolar bosónica a tres cuerpos
L. Fortunato, C.E. Alonso, J.M. Arias, J.E. García-Ramos y A. Vitturi, Phys. Rev. C 84, 014326
(2011)
3. Estudio de caos cuántico y “quantum quentch” en sistemas de interés en óptica cuántica.
P. Pérez-Fernández, P. Cejnar, J.M. Arias, J. Dukelsky, J.E. García Ramos y A. Relaño, Phys. Rev. A 83, 033802
(2011).
P. Pérez-Fernández, A. Relaño, J.M. Arias, J. Dukelsky, J.E. García Ramos y Phys. Rev. E 83, 046208 (2011).
4. Correcciones de tamaño finito en el punto crítico de un Hamiltoniano del modelo vibrónico U(3).
P. Pérez-Fernández, J.M. Arias, J.E. García-Ramos y F. Pérez-Bernal, Phys. Rev. A 83. 062125 (2011).
F. Pérez-Bernal, O. Alvarez-Bajo, J.M. Arias, M.Carvajal, J.E.García-Ramos, D.Larese y
P. Pérez-Fernández, Journal of Physics: Conference Series 284 (2011) 012049.
GRUPO FÍSICA NUCLEAR
UNIVERSIDAD DE GRANADA
Activity in Granada (2011-2012):
Theory
M. Anguiano, G. Co’, V. De Donno and A.M. Lallena (collaboration Granada-Lecce)
Self-consistent Hartree-Fock, continuum RPA and HF+BCS,
with finite range interactions including tensor and spin-orbit terms
•Self-consistent continuum RPA calculations with finite-range interactions
[Phys. Rev. C 83 (2011) 044324]
•Tensor effective interaction in self-consistent RPA calculations
[Phys. Rev. C 83 (2011) 064306]
•Self-consistent continuum RPA calculations of 4He electromagnetic responses
[Phys. Rev. C 84 (2011) 037306]
•Mean-field calculations of exotic nuclei ground states
•Magnetic excitations in nuclei with neutron excess
[Phys. Rev. C 85 (2012) 024322]
[Phys. Rev. C 85 (2012) 034323]
•Nuclear proton and neutron distributions in the detection of weak interacting massive
particles [JCAP accepted]
•Tensor and tensor–isospin terms in the effective Gogny interaction
[submitted to PRC]
•Nuclear properties with finite range interactions in HF+BCS [in preparation]
Activity in Granada (2011-2012):
Theory
Atomic structure and correlations
(Buendía, Gálvez, Sarsa, Maldonado)
•Relativistic, numerically parameterized, optimized, effective potentials for
the ground state of the atoms He through Ra
[At. D. Nuc. D. Tab. 97 (2011) 109-133]
•Relativistic quantum similarities in atoms in position and momentum
spaces
[Physics Letters A 375 (2011) 2544-2549]
•Jastrow correlated and quantum Monte Carlo calculations for the low lying
states of the carbon atom [J. Chem. Phys. 134 (2011) 134102]
Quantum Monte Carlo and Fermions
(Arias de Saavedra, Kalos, Pederiva)
•Cancellation time for correlated random walkers [Mol. Phys.
DOI:10.1080/00268976.2011.604647]
GRUPO FÍSICA NUCLEAR
UNIVERSIDAD CANTABRIA
Modelos relativistas
de estructura nuclear
Grupo (3 doctores): M. López-Quelle, R. Niembro y S. Marcos
Aproximaciones utilizadas:
Hartree y Hartree-Fock+Correlaciones de “pairing”
en BCS, incluyendo los mesones virtuales , ,  y .
Temas investigados:
 Simetría de Pseudo-Espín
[Eur. Phys. J. A 43 (2010) 369]
 Radio cuadrático medio de carga [Phys. Atom. Nucl. 75 (2012) 269]
 Efecto anómalo de los piones en la estructura de capas
[Phys. Atom. Nucl. ( aceptado)]
 Efecto del potencial tensor en la estructura de capas
[Phys. Atom. Nucl. (aceptado)]
Colaboración externa:
L. N. Savushkin (Universidad de St. Petersburgo, Rusia).
GRUPO FÍSICA NUCLEAR TEÓRICA
UNIVERSIDAD DE BARCELONA
Participantes/Investigadores
Mario Centelles (TU)
Joan Martorell (CU)
Assumpta Parreño (PA)
Artur Polls (CU)
Àngels Ramos (CU)
Fco Xavier Viñas (CU)
Volodymyr Magas (RyC)
Emmanuel Chang (PostDoc FIS2008-01661 )
Bruno Juliá-Díaz (PostDoc ICFO)
Bharat K. Sharma (Postdoc CPAN)
Arianna Carbone (FI DGR 2011, Generalitat Catalunya)
Clara Estela Jiménez (Becaria FIS2005-03142)
Marina Melé (Becaria FIS2008-01661)
Axel Pérez-Obiol (Becario APIF, UB)
Colaboraciones:
Granada,Madrid, Valencia,
Bergen,Saclay,Tübingen,
Kiev,Torino,Catania,
Orsay, Lublin, Milano,
Roma, St. Louis, La Plata,
NPLQCD-USA
Líneas de investigación y métodos
Estructura Nuclear y
Sistemas Nucleares Exóticos
núcleos al límite de la estabilidad, extrañeza y charm en el medio nuclear
(funcional de la densidad, funciones espectrales, Wigner-Kirkwood, OBE models, EFT)
EOS y aplicaciones en Astrofísica Nuclear y Colisiones de Iones Pesados
EOS de las estrellas de neutrones, materia nuclear simétrica y asimétrica, RHIC, LHC
(funcionales de la densidad, Funciones de Green autoconsistentes, BHF, DBHF, Modelo Multimodular para RHIC)
Gases atómicos ultrafríos mezclas bosón-fermión, dinámica de los condensados spinoriales
(teoría BCS, uniones Josephson, ecuación de Gross-Pitaevskii)
18 Publicaciones en revistas en 2011 + 17 contribuciones a conference proceedings
3 Phys. Rev. Lett.
1 Mod. Phys. Lett. A
4 Phys. Rev. D
1 New J. Phys
5 Phys. Rev. C
1 Mol. Phys
1 Phys. Lett. B
1 Eur. Phys. Lett.
1 Ukrainian J. Phys
2011 highlights
Suppression of Superfluidity upon Overflow of Neutron Skin of 208Pb, Nuclear Symmetry
Trapped Fermions: Quantal and Thomas-Fermi Energy, and the Parity Radius Experiment
Studies
Parity-violating electron scattering is studied
A new Thomas-Fermi approach to inhomogeneus
at conditions of the PREX experiment of JLab.
superfluid Fermi systems is discussed. The generic fact
The consequences for the determination
that if a fermionic superfluid in BCS regime overflows
of the neutron skin thickness of 208Pb
from a narrow container into a much wider one, pairing
and for the density dependence
is much suppress at the overflow point.
of the nuclear symmetry energy have been analyzed
P. Schuck and X. Viñas,
Phys.Rev. Lett., 107, 205301 (2011)
Sponsors:
X. Roca-Maza, M. Centelles, X. Viñas, M. Warda
Phys. Rev. Lett. 106, 252501 (2011)
GRUPO FÍSICA ATÓMICA, MOLECULAR Y
NUCLEAR
UNIVERSIDAD ISLAS BALEARES
Quantum Physics Group at Mallorca
• We investigate quantum transport at the nanoscale:
1. Numerical Renormalization Group calculations of strongly correlated quantum
dots: J.S. Lim, D. Sanchez, R. Lopez et al., Phys. Rev. B 81, 235309 (2010); Phys.
Rev. B 83, 155325 (2011)
2. Nonequilibrium fluctuation-dissipation theorems: R. Lopez, D. Sanchez et al.,
Phys. Rev. Lett. 104, 076801 (2010)
3. Majorana fermions in nanostructures: J.S. Lim, R. Lopez and Ll. Serra, in
preparation (2011).
4. Quantum information: A. Borras, M. Casas et al., Phys. Rev. A 79, 022112
(2009)
Awarded EPS PhD Thesis
Xavier Roca-Maza
Oscar Moreno
Oscar
Moreno
PhD
1) Gamow-Teller strength distributions
Gamow-Teller (single beta) strength distributions and
b+ half-lives in the lead region (neutron deficient Hg,
Pb, Po isotopes, ISOLDE@CERN experiments).
Shape coexistence and signatures of deformation in
Gamow-Teller patterns, which are robust against
changes in details of the nucleon-nucleon force.
Gamow-Teller strength distributions of stable and
unstable Xe isotopes. Signatures of deformation and
relation with charge-exchange reactions (EXL@FAIR
test of feasibility).
Phys. Rev., C73,054302, 2006
Oscar
Moreno
PhD
2) Two-neutrino double-beta decay
Two-neutrino double-beta decay matrix elements. Several effects
analyzed: nuclear deformation, strength of pairing and Gamow-Teller
correlations, active-shells occupations. Dominance hypotheses in beta
spectra and running sums of matrix elements (NEMO experiment and
others).
Closure approximation for two-neutrino and neutrinoless double-beta
decay. Effect of pairing and nuclear deformation.
Phys. Rev., C81,041303(R), 2010,
J.Phys.G: Nuc.Part.Phys. 36, 015106, 2009
Oscar
Moreno
PhD
3) Parity-violating electron scattering
Parity-violation asymmetry in polarized
electron elastic scattering by nuclei and
its relation to neutron distribution and
neutron skins (208Pb, PREX experiment;
Ca and Sn isotope chains).
Analysis of deviations from reference
value of the asymmetry to study nuclear
isospin
mixing
and
nucleon
strangeness content in N=Z nuclei.
Nucl.Phys., A828, 306 (2009)
u
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d
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Oscar
Moreno
PhD
1) Gamow-Teller strength distributions
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 
Oscar
Moren
o PhD
2) Two-neutrino double-beta decay
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Oscar
Moren
o PhD
3) Parity-violating electron scattering