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Yasuda J, Sasano M, Zegers RGT, Baba H, Bazin D, Chao W, Dozono M, Fukuda N, Inabe N, Isobe T, Jhang G, Kameda D, Kaneko M, Kisamori K, Kobayashi M, Kobayashi N, Kobayashi T, Koyama S, Kondo Y, Krasznahorkay AJ, Kubo T, Kubota Y, Kurata-Nishimura M, Lee CS, Lee JW, Matsuda Y, Milman E, Michimasa S, Motobayashi T, Muecher D, Murakami T, Nakamura T, Nakatsuka N, Ota S, Otsu H, Panin V, Powell W, Reichert S, Sakaguchi S, Sakai H, Sako M, Sato H, Shimizu Y, Shikata M, Shimoura S, Stuhl L, Sumikama T, Suzuki H, Tangwancharoen S, Takaki M, Takeda H, Tako T, Togano Y, Tokieda H, Tsubota J, Uesaka T, Wakasa T, Yako K, Yoneda K, Zenihiro J. Extraction of the Landau-Migdal Parameter from the Gamow-Teller Giant Resonance in ^{132}Sn. PHYSICAL REVIEW LETTERS 2018; 121:132501. [PMID: 30312098 DOI: 10.1103/physrevlett.121.132501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 08/21/2018] [Indexed: 06/08/2023]
Abstract
The key parameter to discuss the possibility of the pion condensation in nuclear matter, i.e., the so-called Landau-Migdal parameter g^{'}, was extracted by measuring the double-differential cross sections for the (p,n) reaction at 216 MeV/u on a neutron-rich doubly magic unstable nucleus, ^{132}Sn with the quality comparable to data taken with stable nuclei. The extracted strengths for Gamow-Teller (GT) transitions from ^{132}Sn leading to ^{132}Sb exhibit the GT giant resonance (GTR) at the excitation energy of 16.3±0.4(stat)±0.4(syst) MeV with the width of Γ=4.7±0.8 MeV. The integrated GT strength up to E_{x}=25 MeV is S_{GT}^{-}=53±5(stat)_{-10}^{+11}(syst), corresponding to 56% of Ikeda's sum rule of 3(N-Z)=96. The present result accurately constrains the Landau-Migdal parameter as g^{'}=0.68±0.07, thanks to the high sensitivity of the GTR energy to g^{'}. In combination with previous studies on the GTR for ^{90}Zr and ^{208}Pb, the result of this work shows the constancy of this parameter in the nuclear chart region with (N-Z)/A=0.11 to 0.24 and A=90 to 208.
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Affiliation(s)
- J Yasuda
- Department of Physics, Kyushu University, Nishi, Fukuoka 819-0395, Japan
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - M Sasano
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - R G T Zegers
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - H Baba
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - D Bazin
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - W Chao
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - M Dozono
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - N Fukuda
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - N Inabe
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - T Isobe
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - G Jhang
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - D Kameda
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - M Kaneko
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - K Kisamori
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Center for Nuclear Study, University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - M Kobayashi
- Center for Nuclear Study, University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - N Kobayashi
- Department of Physics, University of Tokyo, Tokyo 113-0033, Japan
| | - T Kobayashi
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Department of Physics, Tohoku University, Miyagi 980-8578, Japan
| | - S Koyama
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Department of Physics, University of Tokyo, Tokyo 113-0033, Japan
| | - Y Kondo
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
| | - A J Krasznahorkay
- ATOMKI, Institute for Nuclear Research, Hungarian Academy of Sciences, P. O. Box 51, H-4001 Debrecen, Hungary
| | - T Kubo
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - Y Kubota
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Center for Nuclear Study, University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | | | - C S Lee
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Center for Nuclear Study, University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - J W Lee
- Department of Physics, Korea University, Seoul 02841, Republic of Korea
| | - Y Matsuda
- Department of Physics, Faculty of Science and Engineering, Konan University, 8-9-1 Higashinada, Kobe, Hyogo 658-8501, Japan
| | - E Milman
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Department of Physics, Kyungpook National University, Daegu 702-701, Korea
| | - S Michimasa
- Center for Nuclear Study, University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - T Motobayashi
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - D Muecher
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Technical University of Munich, D-85748 Garching, Germany
- Department of Physics, University of Guelph, Ontario N1G 2W1, Canada
| | - T Murakami
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - T Nakamura
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
| | - N Nakatsuka
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - S Ota
- Center for Nuclear Study, University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - H Otsu
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - V Panin
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - W Powell
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - S Reichert
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Technical University of Munich, D-85748 Garching, Germany
| | - S Sakaguchi
- Department of Physics, Kyushu University, Nishi, Fukuoka 819-0395, Japan
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - H Sakai
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - M Sako
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - H Sato
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - Y Shimizu
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - M Shikata
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
| | - S Shimoura
- Center for Nuclear Study, University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - L Stuhl
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - T Sumikama
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Department of Physics, Tohoku University, Miyagi 980-8578, Japan
| | - H Suzuki
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - S Tangwancharoen
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - M Takaki
- Center for Nuclear Study, University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - H Takeda
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - T Tako
- Department of Physics, Tohoku University, Miyagi 980-8578, Japan
| | - Y Togano
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
- Department of Physics, Rikkyo University, Tokyo 171-8501, Japan
| | - H Tokieda
- Center for Nuclear Study, University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - J Tsubota
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
| | - T Uesaka
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - T Wakasa
- Department of Physics, Kyushu University, Nishi, Fukuoka 819-0395, Japan
| | - K Yako
- Center for Nuclear Study, University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - K Yoneda
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - J Zenihiro
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
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Politi G, Acosta L, Andrés MV, Auditore L, Beck C, Cap T, Cardella G, Catara F, Colonna M, De Filippo E, D'Onofrio A, Geraci E, Gnoffo B, Kalandarov S, La Commara M, Lanza EG, Lanzalone G, Maiolino C, Martorana NS, Pagano A, Pagano EV, Papa M, Piasecki E, Pirrone S, Quattrocchi L, Rizzo F, Russotto P, Santonocito D, Siwek-Wilczynska K, Trifirò A, Trimarchi M, Vitturi A. Isospin effects on reaction dynamics at Fermi energies. EPJ WEB OF CONFERENCES 2018. [DOI: 10.1051/epjconf/201819407003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The study of nuclei properties and of collision dynamics is a very active research field whose result have implications in different domains as for example astrophysics. The present and future facilities delivering radioactive ion beams with high intensity allow to extend these studies in the region far from the stability valley. New insight has thus been found on the effects of neutron richness on reaction mechanisms as well as on nuclear structure and nuclear matter properties, as for instance, the role of symmetry energy term of the nuclear Equation of State. The presence of diverse reaction products demands for highly performing and very specialized devices, also able to disentangle among different mechanisms, from fast dynamical processes to statistical emission from equilibrated sources. Numerous studies of the effects of N/Z ratio on fusion and associated processes can be found at different energies, together with many examples of the influence of neutron richness on the reaction time scale and the competition between equilibrated and prompt processes. A survey of very recent findings obtained with the CHIMERA and FARCOS devices is presented.
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Lanza E, Vitturi A, Andrés M, Catara F. Microscopic nuclear form factor for the pygmy dipole resonance. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201611706017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Achakovskiy O, Avdeenkov A, Kamerdzhiev S. Impact of phonon coupling on the radiative nuclear reaction characteristics. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201610705002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Blasi N, Giaz A, Boiano C, Brambilla S, Camera F, Million B, Riboldi S. Position sensitivity in 3"×3" Spectroscopic LaBr3:Ce Crystals. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/1742-6596/620/1/012004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Achakovskiy O, Avdeenkov A, Goriely S, Kamerdzhiev S, Krewald S, Voitenkov D. Microscopic nature of the photon strength function: stable and unstable Ni and Sn isotopes. EPJ WEB OF CONFERENCES 2015. [DOI: 10.1051/epjconf/20159301034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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7
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von Neumann-Cosel P. Complete Electric Dipole Response in 120Sn and 208Pb and Implications for Neutron Skin and Symmetry Energy. EPJ WEB OF CONFERENCES 2015. [DOI: 10.1051/epjconf/20159301029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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8
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Isaak J, Löher B, Savran D, Aumann T, Beller J, Cooper N, Derya V, Duchêne M, Endres J, Fiori E, Kelley J, Knörzer M, Pietralla N, Ponomarev V, Romig C, Scheck M, Scheit H, Silva J, Tonchev A, Tornow W, Weller H, Werner V, Zilges A, Zweidinger M. Decay pattern of the Pygmy Dipole Resonance in 140Ce. EPJ WEB OF CONFERENCES 2015. [DOI: 10.1051/epjconf/20159301048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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9
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Zilges A, Savran D. The Pygmy Dipole Resonance – past, presence, and future. EPJ WEB OF CONFERENCES 2015. [DOI: 10.1051/epjconf/20159301028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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10
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Tribble RE, Bertulani CA, Cognata ML, Mukhamedzhanov AM, Spitaleri C. Indirect techniques in nuclear astrophysics: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2014; 77:106901. [PMID: 25313189 DOI: 10.1088/0034-4885/77/10/106901] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this review, we discuss the present status of three indirect techniques that are used to determine reaction rates for stellar burning processes, asymptotic normalization coefficients, the Trojan Horse method and Coulomb dissociation. A comprehensive review of the theory behind each of these techniques is presented. This is followed by an overview of the experiments that have been carried out using these indirect approaches.
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Affiliation(s)
- R E Tribble
- Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA
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11
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Vandebrouck M, Gibelin J, Khan E, Achouri NL, Baba H, Beaumel D, Blumenfeld Y, Caamaño M, Càceres L, Colò G, Delaunay F, Fernandez-Dominguez B, Garg U, Grinyer GF, Harakeh MN, Kalantar-Nayestanaki N, Keeley N, Mittig W, Pancin J, Raabe R, Roger T, Roussel-Chomaz P, Savajols H, Sorlin O, Stodel C, Suzuki D, Thomas JC. Measurement of the isoscalar monopole response in the neutron-rich nucleus 68Ni. PHYSICAL REVIEW LETTERS 2014; 113:032504. [PMID: 25083638 DOI: 10.1103/physrevlett.113.032504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Indexed: 06/03/2023]
Abstract
The isoscalar monopole response has been measured in the unstable nucleus (68)Ni using inelastic alpha scattering at 50A MeV in inverse kinematics with the active target MAYA at GANIL. The isoscalar giant monopole resonance (ISGMR) centroid was determined to be 21.1 ± 1.9 MeV and indications for a soft monopole mode are provided for the first time at 12.9 ± 1.0 MeV. Analysis of the corresponding angular distributions using distorted-wave-born approximation with random-phase approximation transition densities indicates that the L = 0 multipolarity dominates the cross section for the ISGMR and significantly contributes to the low-energy mode. The L=0 part of this low-energy mode, the soft monopole mode, is dominated by neutron excitations. This demonstrates the relevance of inelastic alpha scattering in inverse kinematics in order to probe both the ISGMR and isoscalar soft modes in neutron-rich nuclei.
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Affiliation(s)
- M Vandebrouck
- IPN Orsay, Université Paris Sud, IN2P3-CNRS, F-91406 Orsay Cedex, France and LPC Caen, ENSICAEN, Université de Caen, CNRS/IN2P3, F-14050 CAEN Cedex, France
| | - J Gibelin
- LPC Caen, ENSICAEN, Université de Caen, CNRS/IN2P3, F-14050 CAEN Cedex, France
| | - E Khan
- IPN Orsay, Université Paris Sud, IN2P3-CNRS, F-91406 Orsay Cedex, France
| | - N L Achouri
- LPC Caen, ENSICAEN, Université de Caen, CNRS/IN2P3, F-14050 CAEN Cedex, France
| | - H Baba
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - D Beaumel
- IPN Orsay, Université Paris Sud, IN2P3-CNRS, F-91406 Orsay Cedex, France
| | - Y Blumenfeld
- IPN Orsay, Université Paris Sud, IN2P3-CNRS, F-91406 Orsay Cedex, France
| | - M Caamaño
- Universidade de Santiago de Compostela, E-15706 Santiago de Compostela, Spain
| | - L Càceres
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen, France
| | - G Colò
- Dipartimento de Fisica Università degli Studi di Milano and INFN, Sezione di Milano, 20133 Milano, Italy
| | - F Delaunay
- LPC Caen, ENSICAEN, Université de Caen, CNRS/IN2P3, F-14050 CAEN Cedex, France
| | | | - U Garg
- Physics Department, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - G F Grinyer
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen, France
| | - M N Harakeh
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen, France and KVI-CART, University of Groningen, NL-9747 AA Groningen, The Netherlands
| | | | - N Keeley
- National Centre for Nuclear Research ul. Andrzeja Soł tana 7, 05-400 Otwock, Poland
| | - W Mittig
- NSCL, Michigan State University, East Lansing, Michigan 48824-1321, USA
| | - J Pancin
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen, France
| | - R Raabe
- Instituut voor Kern- en Stralingsfysica, KU Leuven, B-3001 Leuven, Belgium
| | - T Roger
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen, France and Instituut voor Kern- en Stralingsfysica, KU Leuven, B-3001 Leuven, Belgium
| | | | - H Savajols
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen, France
| | - O Sorlin
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen, France
| | - C Stodel
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen, France
| | - D Suzuki
- IPN Orsay, Université Paris Sud, IN2P3-CNRS, F-91406 Orsay Cedex, France and NSCL, Michigan State University, East Lansing, Michigan 48824-1321, USA
| | - J C Thomas
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen, France
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Crespi FCL, Bracco A, Nicolini R, Mengoni D, Pellegri L, Lanza EG, Leoni S, Maj A, Kmiecik M, Avigo R, Benzoni G, Blasi N, Boiano C, Bottoni S, Brambilla S, Camera F, Ceruti S, Giaz A, Million B, Morales AI, Vandone V, Wieland O, Bednarczyk P, Ciemała M, Grebosz J, Krzysiek M, Mazurek K, Zieblinski M, Bazzacco D, Bellato M, Birkenbach B, Bortolato D, Calore E, Cederwall B, Charles L, de Angelis G, Désesquelles P, Eberth J, Farnea E, Gadea A, Görgen A, Gottardo A, Isocrate R, Jolie J, Jungclaus A, Karkour N, Korten W, Menegazzo R, Michelagnoli C, Molini P, Napoli DR, Pullia A, Recchia F, Reiter P, Rosso D, Sahin E, Salsac MD, Siebeck B, Siem S, Simpson J, Söderström PA, Stezowski O, Theisen C, Ur C, Valiente-Dobón JJ. Isospin character of low-lying pygmy dipole states in 208Pb via inelastic scattering of 17O ions. PHYSICAL REVIEW LETTERS 2014; 113:012501. [PMID: 25032921 DOI: 10.1103/physrevlett.113.012501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Indexed: 06/03/2023]
Abstract
The properties of pygmy dipole states in 208Pb were investigated using the 208Pb(17O, 17O'γ) reaction at 340 MeV and measuring the γ decay with high resolution with the AGATA demonstrator array. Cross sections and angular distributions of the emitted γ rays and of the scattered particles were measured. The results are compared with (γ, γ') and (p, p') data. The data analysis with the distorted wave Born approximation approach gives a good description of the elastic scattering and of the inelastic excitation of the 2+ and 3- states. For the dipole transitions a form factor obtained by folding a microscopically calculated transition density was used for the first time. This has allowed us to extract the isoscalar component of the 1- excited states from 4 to 8 MeV.
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Affiliation(s)
- F C L Crespi
- Dipartimento di Fisica dell'Università degli Studi di Milano, I-20133 Milano, Italy and INFN, Sezione di Milano, I-20133 Milano, Italy
| | - A Bracco
- Dipartimento di Fisica dell'Università degli Studi di Milano, I-20133 Milano, Italy and INFN, Sezione di Milano, I-20133 Milano, Italy
| | - R Nicolini
- Dipartimento di Fisica dell'Università degli Studi di Milano, I-20133 Milano, Italy and INFN, Sezione di Milano, I-20133 Milano, Italy
| | - D Mengoni
- Dipartimento di Fisica dell'Università degli Studi di Padova, I-35131 Padova, Italy and INFN, Sezione di Padova, I-35131 Padova, Italy
| | - L Pellegri
- Dipartimento di Fisica dell'Università degli Studi di Milano, I-20133 Milano, Italy and INFN, Sezione di Milano, I-20133 Milano, Italy
| | - E G Lanza
- INFN, Sezione di Catania, I-95123 Catania, Italy
| | - S Leoni
- Dipartimento di Fisica dell'Università degli Studi di Milano, I-20133 Milano, Italy and INFN, Sezione di Milano, I-20133 Milano, Italy
| | - A Maj
- The Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Krakow, Poland
| | - M Kmiecik
- The Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Krakow, Poland
| | - R Avigo
- Dipartimento di Fisica dell'Università degli Studi di Milano, I-20133 Milano, Italy and INFN, Sezione di Milano, I-20133 Milano, Italy
| | - G Benzoni
- INFN, Sezione di Milano, I-20133 Milano, Italy
| | - N Blasi
- INFN, Sezione di Milano, I-20133 Milano, Italy
| | - C Boiano
- INFN, Sezione di Milano, I-20133 Milano, Italy
| | - S Bottoni
- Dipartimento di Fisica dell'Università degli Studi di Milano, I-20133 Milano, Italy and INFN, Sezione di Milano, I-20133 Milano, Italy
| | - S Brambilla
- INFN, Sezione di Milano, I-20133 Milano, Italy
| | - F Camera
- Dipartimento di Fisica dell'Università degli Studi di Milano, I-20133 Milano, Italy and INFN, Sezione di Milano, I-20133 Milano, Italy
| | - S Ceruti
- Dipartimento di Fisica dell'Università degli Studi di Milano, I-20133 Milano, Italy and INFN, Sezione di Milano, I-20133 Milano, Italy
| | - A Giaz
- INFN, Sezione di Milano, I-20133 Milano, Italy
| | - B Million
- INFN, Sezione di Milano, I-20133 Milano, Italy
| | - A I Morales
- Dipartimento di Fisica dell'Università degli Studi di Milano, I-20133 Milano, Italy and INFN, Sezione di Milano, I-20133 Milano, Italy
| | - V Vandone
- Dipartimento di Fisica dell'Università degli Studi di Milano, I-20133 Milano, Italy and INFN, Sezione di Milano, I-20133 Milano, Italy
| | - O Wieland
- INFN, Sezione di Milano, I-20133 Milano, Italy
| | - P Bednarczyk
- The Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Krakow, Poland
| | - M Ciemała
- The Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Krakow, Poland
| | - J Grebosz
- The Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Krakow, Poland
| | - M Krzysiek
- The Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Krakow, Poland
| | - K Mazurek
- The Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Krakow, Poland
| | - M Zieblinski
- The Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Krakow, Poland
| | - D Bazzacco
- INFN, Sezione di Padova, I-35131 Padova, Italy
| | - M Bellato
- INFN, Sezione di Padova, I-35131 Padova, Italy
| | - B Birkenbach
- Institut für Kernphysik, Universität zu Köln, D-50937 Köln, Germany
| | - D Bortolato
- Dipartimento di Fisica dell'Università degli Studi di Padova, I-35131 Padova, Italy and INFN, Sezione di Padova, I-35131 Padova, Italy
| | - E Calore
- INFN, Laboratori Nazionali di Legnaro, Legnaro I-35020, Italy
| | - B Cederwall
- Department of Physics, Royal Institute of Technology, SE-10691 Stockholm, Sweden
| | - L Charles
- Institut Pluridisciplinaire Hubert Curien IPHC, CNRS/IN2P3 and Université de Strasbourg BP 28, F-67037 Strasbourg Cedex 2, France
| | - G de Angelis
- INFN, Laboratori Nazionali di Legnaro, Legnaro I-35020, Italy
| | - P Désesquelles
- Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse CSNSM, CNRS/IN2P3 and Université Paris-Sud, F-91405 Orsay Campus, France
| | - J Eberth
- Institut für Kernphysik, Universität zu Köln, D-50937 Köln, Germany
| | - E Farnea
- INFN, Sezione di Padova, I-35131 Padova, Italy
| | - A Gadea
- IFIC, CSIC-Universitat de València, E-46980 Valéncia, Spain
| | - A Görgen
- Department of Physics, University of Oslo, N-0316 Oslo, Norway
| | - A Gottardo
- Dipartimento di Fisica dell'Università degli Studi di Padova, I-35131 Padova, Italy and INFN, Laboratori Nazionali di Legnaro, Legnaro I-35020, Italy
| | - R Isocrate
- INFN, Sezione di Padova, I-35131 Padova, Italy
| | - J Jolie
- Institut für Kernphysik, Universität zu Köln, D-50937 Köln, Germany
| | - A Jungclaus
- Instituto de Estructura de la Materia, CSIC, Madrid, E-28006 Madrid, Spain
| | - N Karkour
- Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse CSNSM, CNRS/IN2P3 and Université Paris-Sud, F-91405 Orsay Campus, France
| | - W Korten
- Institut de Recherche sur les lois Fondamentales de l'Univers IRFU, CEA/DSM, Centre CEA de Saclay, F-91191 Gif-sur-Yvette Cedex, France
| | - R Menegazzo
- INFN, Sezione di Padova, I-35131 Padova, Italy
| | - C Michelagnoli
- Dipartimento di Fisica dell'Università degli Studi di Padova, I-35131 Padova, Italy and INFN, Sezione di Padova, I-35131 Padova, Italy
| | - P Molini
- INFN, Laboratori Nazionali di Legnaro, Legnaro I-35020, Italy
| | - D R Napoli
- INFN, Laboratori Nazionali di Legnaro, Legnaro I-35020, Italy
| | - A Pullia
- Dipartimento di Fisica dell'Università degli Studi di Milano, I-20133 Milano, Italy and INFN, Sezione di Milano, I-20133 Milano, Italy
| | - F Recchia
- Dipartimento di Fisica dell'Università degli Studi di Padova, I-35131 Padova, Italy and INFN, Sezione di Padova, I-35131 Padova, Italy
| | - P Reiter
- Institut für Kernphysik, Universität zu Köln, D-50937 Köln, Germany
| | - D Rosso
- INFN, Laboratori Nazionali di Legnaro, Legnaro I-35020, Italy
| | - E Sahin
- INFN, Laboratori Nazionali di Legnaro, Legnaro I-35020, Italy
| | - M D Salsac
- Institut de Recherche sur les lois Fondamentales de l'Univers IRFU, CEA/DSM, Centre CEA de Saclay, F-91191 Gif-sur-Yvette Cedex, France
| | - B Siebeck
- Institut für Kernphysik, Universität zu Köln, D-50937 Köln, Germany
| | - S Siem
- Department of Physics, University of Oslo, N-0316 Oslo, Norway
| | - J Simpson
- STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom
| | - P-A Söderström
- Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala, Sweden
| | - O Stezowski
- Université de Lyon, F-69622, Lyon, France and Université Lyon 1, Villeurbanne; CNRS/IN2P3, UMR5822, IPNL, France
| | - Ch Theisen
- Institut de Recherche sur les lois Fondamentales de l'Univers IRFU, CEA/DSM, Centre CEA de Saclay, F-91191 Gif-sur-Yvette Cedex, France
| | - C Ur
- INFN, Sezione di Padova, I-35131 Padova, Italy
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13
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Paar N, Horvat A. Probing the neutron skin thickness in collective modes of excitation. EPJ WEB OF CONFERENCES 2014. [DOI: 10.1051/epjconf/20146602078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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14
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Baran V, Colonna M, Di Toro M, Croitoru A, Dumitru D. Collective features of nuclear dynamics with exotic nuclei within microscopic transport models. EPJ WEB OF CONFERENCES 2014. [DOI: 10.1051/epjconf/20146603004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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15
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Bracco A, Ceruti S, Pellegri L. Nuclear Structure aspects of gamma decay from giant resonances. EPJ WEB OF CONFERENCES 2014. [DOI: 10.1051/epjconf/20147806002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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16
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Savran D. Experimental results on the Pygmy Dipole Resonance. EPJ WEB OF CONFERENCES 2014. [DOI: 10.1051/epjconf/20146602094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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17
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Crespi F, Kmiecik M, Bracco A, Leoni S, Maj A, Benzoni G, Blasi N, Boiano C, Bottoni S, Brambilla S, Camera F, Ceruti S, Giaz A, Million B, Morales A, Nicolini R, Pellegri L, Riboldi S, Vandone V, Wieland O, Bednarczyk P, Ciemala M, Grebosz J, Krzysiek M, Mazurek K, Zieblinski M, Bazzacco D, Bellato M, Birkenbach B, Bortolato D, Calore E, Angelis GD, Farnea E, Gadea A, Görgen A, Gottardo A, Isocrate R, Lenzi S, Lunardi S, Mengoni D, Michelagnoli C, Molini P, Napoli D, Recchia F, Sahin E, Siebeck B, Siem S, Ur C, Dobon JV. Study of the γdecay of high-lying states in 208Pb via inelastic scattering of 17O ions. EPJ WEB OF CONFERENCES 2014. [DOI: 10.1051/epjconf/20146602023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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18
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Rossi DM, Adrich P, Aksouh F, Alvarez-Pol H, Aumann T, Benlliure J, Böhmer M, Boretzky K, Casarejos E, Chartier M, Chatillon A, Cortina-Gil D, Datta Pramanik U, Emling H, Ershova O, Fernandez-Dominguez B, Geissel H, Gorska M, Heil M, Johansson HT, Junghans A, Kelic-Heil A, Kiselev O, Klimkiewicz A, Kratz JV, Krücken R, Kurz N, Labiche M, Le Bleis T, Lemmon R, Litvinov YA, Mahata K, Maierbeck P, Movsesyan A, Nilsson T, Nociforo C, Palit R, Paschalis S, Plag R, Reifarth R, Savran D, Scheit H, Simon H, Sümmerer K, Wagner A, Waluś W, Weick H, Winkler M. Measurement of the dipole polarizability of the unstable neutron-rich nucleus 68Ni. PHYSICAL REVIEW LETTERS 2013; 111:242503. [PMID: 24483648 DOI: 10.1103/physrevlett.111.242503] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Indexed: 06/03/2023]
Abstract
The E1 strength distribution in 68Ni has been investigated using Coulomb excitation in inverse kinematics at the R3B-LAND setup and by measuring the invariant mass in the one- and two-neutron decay channels. The giant dipole resonance and a low-lying peak (pygmy dipole resonance) have been observed at 17.1(2) and 9.55(17) MeV, respectively. The measured dipole polarizability is compared to relativistic random phase approximation calculations yielding a neutron-skin thickness of 0.17(2) fm. A method and analysis applicable to neutron-rich nuclei has been developed, allowing for a precise determination of neutron skins in nuclei as a function of neutron excess.
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Affiliation(s)
- D M Rossi
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany and Institut für Kernchemie, Johannes Gutenberg-Universität, D-55128 Mainz, Germany
| | - P Adrich
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - F Aksouh
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - H Alvarez-Pol
- University of Santiago de Compostela, E-15705 Santiago de Compostela, Spain
| | - T Aumann
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany and Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
| | - J Benlliure
- University of Santiago de Compostela, E-15705 Santiago de Compostela, Spain
| | - M Böhmer
- Physik-Department E12, Technische Universität München, D-85748 Garching, Germany
| | - K Boretzky
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | | | - M Chartier
- University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - A Chatillon
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - D Cortina-Gil
- University of Santiago de Compostela, E-15705 Santiago de Compostela, Spain
| | | | - H Emling
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - O Ershova
- Institut für Angewandte Physik, Goethe Universität, D-60438 Frankfurt am Main, Germany
| | - B Fernandez-Dominguez
- University of Santiago de Compostela, E-15705 Santiago de Compostela, Spain and University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - H Geissel
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - M Gorska
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - M Heil
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - H T Johansson
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany and Chalmers University of Technology, SE-41296 Göteborg, Sweden
| | - A Junghans
- Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden, Germany
| | - A Kelic-Heil
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - O Kiselev
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany and Institut für Kernchemie, Johannes Gutenberg-Universität, D-55128 Mainz, Germany
| | - A Klimkiewicz
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany and Jagiellonian University, PL-30-059 Krakow, Poland
| | - J V Kratz
- Institut für Kernchemie, Johannes Gutenberg-Universität, D-55128 Mainz, Germany
| | - R Krücken
- Physik-Department E12, Technische Universität München, D-85748 Garching, Germany
| | - N Kurz
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - M Labiche
- University of the West of Scotland, Paisley PA1 2BE, United Kingdom and STFC Daresbury Laboratory, Warrington WA4 4AD, United Kingdom
| | - T Le Bleis
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany and Institut für Angewandte Physik, Goethe Universität, D-60438 Frankfurt am Main, Germany and Institut Pluridisciplinaire Hubert Curien, F-67037 Strasbourg, France
| | - R Lemmon
- STFC Daresbury Laboratory, Warrington WA4 4AD, United Kingdom
| | - Yu A Litvinov
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - K Mahata
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany and Bhabha Atomic Research Centre, Mumbai 400-085, India
| | - P Maierbeck
- Physik-Department E12, Technische Universität München, D-85748 Garching, Germany
| | - A Movsesyan
- Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
| | - T Nilsson
- Chalmers University of Technology, SE-41296 Göteborg, Sweden
| | - C Nociforo
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - R Palit
- Tata Institute of Fundamental Research, Mumbai 400-005, India
| | - S Paschalis
- Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany and University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - R Plag
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany and Institut für Angewandte Physik, Goethe Universität, D-60438 Frankfurt am Main, Germany
| | - R Reifarth
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany and Institut für Angewandte Physik, Goethe Universität, D-60438 Frankfurt am Main, Germany
| | - D Savran
- ExtreMe Matter Institute EMMI and Research Division, GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany and Frankfurt Institute for Advanced Studies, D-60438 Frankfurt am Main, Germany
| | - H Scheit
- Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
| | - H Simon
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - K Sümmerer
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - A Wagner
- Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden, Germany
| | - W Waluś
- Jagiellonian University, PL-30-059 Krakow, Poland
| | - H Weick
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - M Winkler
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
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19
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Bracco A, Crespi F. Study of the γ decay of high-lying states in208Pb via inelastic scattering of17O ions. EPJ WEB OF CONFERENCES 2012. [DOI: 10.1051/epjconf/20123803001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Tamii A, Poltoratska I, von Neumann-Cosel P, Fujita Y, Adachi T, Bertulani CA, Carter J, Dozono M, Fujita H, Fujita K, Hatanaka K, Ishikawa D, Itoh M, Kawabata T, Kalmykov Y, Krumbholz AM, Litvinova E, Matsubara H, Nakanishi K, Neveling R, Okamura H, Ong HJ, Ozel-Tashenov B, Ponomarev VY, Richter A, Rubio B, Sakaguchi H, Sakemi Y, Sasamoto Y, Shimbara Y, Shimizu Y, Smit FD, Suzuki T, Tameshige Y, Wambach J, Yamada R, Yosoi M, Zenihiro J. Complete electric dipole response and the neutron skin in 208Pb. PHYSICAL REVIEW LETTERS 2011; 107:062502. [PMID: 21902316 DOI: 10.1103/physrevlett.107.062502] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Indexed: 05/31/2023]
Abstract
A benchmark experiment on (208)Pb shows that polarized proton inelastic scattering at very forward angles including 0° is a powerful tool for high-resolution studies of electric dipole (E1) and spin magnetic dipole (M1) modes in nuclei over a broad excitation energy range to test up-to-date nuclear models. The extracted E1 polarizability leads to a neutron skin thickness r(skin) = 0.156(-0.021)(+0.025) fm in (208)Pb derived within a mean-field model [Phys. Rev. C 81, 051303 (2010)], thereby constraining the symmetry energy and its density dependence relevant to the description of neutron stars.
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Affiliation(s)
- A Tamii
- Research Center for Nuclear Physics, Osaka University, Ibaraki, Japan
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21
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Endres J, Litvinova E, Savran D, Butler PA, Harakeh MN, Harissopulos S, Herzberg RD, Krücken R, Lagoyannis A, Pietralla N, Ponomarev VY, Popescu L, Ring P, Scheck M, Sonnabend K, Stoica VI, Wörtche HJ, Zilges A. Isospin character of the pygmy dipole resonance in 124Sn. PHYSICAL REVIEW LETTERS 2010; 105:212503. [PMID: 21231295 DOI: 10.1103/physrevlett.105.212503] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Indexed: 05/30/2023]
Abstract
The pygmy dipole resonance has been studied in the proton-magic nucleus 124Sn with the (α, α'γ) coincidence method at Eα=136 MeV. The comparison with results of photon-scattering experiments reveals a splitting into two components with different structure: one group of states which is excited in (α, α'γ) as well as in (γ, γ') reactions and a group of states at higher energies which is only excited in (γ, γ') reactions. Calculations with the self-consistent relativistic quasiparticle time-blocking approximation and the quasiparticle phonon model are in qualitative agreement with the experimental results and predict a low-lying isoscalar component dominated by neutron-skin oscillations and a higher-lying more isovector component on the tail of the giant dipole resonance.
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Affiliation(s)
- J Endres
- Institut für Kernphysik, Universität zu Köln, Zülpicher Straße 77, D-50937 Köln, Germany.
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22
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Litvinova E, Ring P, Tselyaev V. Mode coupling and the pygmy dipole resonance in a relativistic two-phonon model. PHYSICAL REVIEW LETTERS 2010; 105:022502. [PMID: 20867704 DOI: 10.1103/physrevlett.105.022502] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Indexed: 05/29/2023]
Abstract
A new class of many-body models, based on covariant density functional theory for excited states, is presented. It allows a parameter free description of the fragmentation of nuclear states induced by mode coupling of two-quasiparticle and two-phonon configurations. As compared to earlier methods it provides a consistent and parameter free theory of the fine structure of nuclear resonances. The method is applied very successfully to investigate the newly discovered low-lying dipole excitations in Sn and Ni isotopes with large neutron excess.
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Affiliation(s)
- Elena Litvinova
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany and Institut für Theoretische Physik, Goethe-Universität, 60438 Frankfurt am Main, Germany and Institute of Physics and Power Engineering, 249033 Obninsk, Russia
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23
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Tonchev AP, Hammond SL, Kelley JH, Kwan E, Lenske H, Rusev G, Tornow W, Tsoneva N. Spectral structure of the pygmy dipole resonance. PHYSICAL REVIEW LETTERS 2010; 104:072501. [PMID: 20366874 DOI: 10.1103/physrevlett.104.072501] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Indexed: 05/29/2023]
Abstract
High-sensitivity studies of E1 and M1 transitions observed in the reaction 138Ba(gamma,gamma{'}) at energies below the one-neutron separation energy have been performed using the nearly monoenergetic and 100% linearly polarized photon beams of the HIgammaS facility. The electric dipole character of the so-called "pygmy" dipole resonance was experimentally verified for excitations from 4.0 to 8.6 MeV. The fine structure of the M1 "spin-flip" mode was observed for the first time in N=82 nuclei.
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Affiliation(s)
- A P Tonchev
- Duke University, Durham, North Carolina 27708-0308, USA
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24
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Paar N, Niu YF, Vretenar D, Meng J. Isoscalar and isovector splitting of pygmy dipole structures. PHYSICAL REVIEW LETTERS 2009; 103:032502. [PMID: 19659271 DOI: 10.1103/physrevlett.103.032502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2009] [Revised: 05/29/2009] [Indexed: 05/28/2023]
Abstract
The electric-dipole response of 140Ce is investigated using the fully consistent relativistic quasiparticle random phase approximation. By analyzing the isospin structure of the E1 response, it is shown that the low-energy (pygmy) strength separates into two segments with different isospin character. The more pronounced pygmy structure at lower energy is composed of predominantly isoscalar states with surface-peaked transition densities. At somewhat higher energy the calculated E1 strength is primarily of isovector character, as expected for the low-energy tail of the giant dipole resonance. The results are in qualitative agreement with those obtained in recent (gamma, gamma') and (alpha, alpha'gamma) experiments, and provide a simple explanation for the splitting of low-energy E1 strength into two groups of states with different isospin structure and radial dependence of the corresponding transition densities.
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Affiliation(s)
- N Paar
- Physics Department, Faculty of Science, University of Zagreb, Croatia.
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25
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Agvaanluvsan U, Larsen AC, Chankova R, Guttormsen M, Mitchell GE, Schiller A, Siem S, Voinov A. Enhanced radiative strength in the quasicontinuum of 117Sn. PHYSICAL REVIEW LETTERS 2009; 102:162504. [PMID: 19518705 DOI: 10.1103/physrevlett.102.162504] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Revised: 11/10/2008] [Indexed: 05/27/2023]
Abstract
The radiative strength function of 117Sn has been measured up to the neutron separation energy using the (3He, 3He' gamma) reaction. An increase in the slope of the strength function around E gamma=4.5 MeV indicates the onset of a resonancelike structure, giving a significant enhancement of the radiative strength function compared to standard models in the energy region 4.5<or=E gamma<or=8.0 MeV. For the first time, the functional form of this resonancelike structure has been measured in an odd tin nucleus below neutron threshold in the quasicontinuum region.
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