26
|
Paul N, Obertelli A, Bertulani CA, Corsi A, Doornenbal P, Rodriguez-Sanchez JL, Authelet G, Baba H, Calvet D, Château F, Chen S, Delbart A, Gheller JM, Giganon A, Gillibert A, Isobe T, Lapoux V, Matsushita M, Momiyama S, Motobayashi T, Niikura M, Otsu H, Péron C, Peyaud A, Pollacco EC, Roussé JY, Sakurai H, Santamaria C, Sasano M, Shiga Y, Steppenbeck D, Takeuchi S, Taniuchi R, Uesaka T, Wang H, Yoneda K, Ando T, Arici T, Blazhev A, Browne F, Bruce AM, Carroll R, Chung LX, Cortés ML, Dewald M, Ding B, Dombradi Z, Flavigny F, Franchoo S, Giacoppo F, Górska M, Gottardo A, Hadynska-Klek K, Korkulu Z, Koyama S, Kubota Y, Jungclaus A, Lee J, Lettmann M, Linh BD, Liu J, Liu Z, Lizarazo C, Louchart C, Lozeva R, Matsui K, Miyazaki T, Moschner K, Nagamine S, Nakatsuka N, Nita C, Nishimura S, Nobs CR, Olivier L, Ota S, Patel Z, Podolyák Z, Rudigier M, Sahin E, Saito TY, Shand C, Söderström PA, Stefan IG, Sumikama T, Suzuki D, Orlandi R, Vaquero V, Vajta Z, Werner V, Wimmer K, Wu J, Xu Z. Prominence of Pairing in Inclusive (p,2p) and (p,pn) Cross Sections from Neutron-Rich Nuclei. PHYSICAL REVIEW LETTERS 2019; 122:162503. [PMID: 31075035 DOI: 10.1103/physrevlett.122.162503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Indexed: 06/09/2023]
Abstract
Fifty-five inclusive single nucleon-removal cross sections from medium mass neutron-rich nuclei impinging on a hydrogen target at ∼250 MeV/nucleon are measured at the RIKEN Radioactive Isotope Beam Factory. Systematically higher cross sections are found for proton removal from nuclei with an even number of protons as compared to odd-proton number projectiles for a given neutron separation energy. Neutron removal cross sections display no even-odd splitting, contrary to nuclear cascade model predictions. Both effects are understood through simple considerations of neutron separation energies and bound state level densities originating in pairing correlations in the daughter nuclei. These conclusions are supported by comparison with semimicroscopic model predictions, highlighting the enhanced role of low-lying level densities in nucleon-removal cross sections from loosely bound nuclei.
Collapse
|
27
|
Ajito K, Ueno Y, Kim JY, Sumikama T. Capturing the Freeze-Drying Dynamics of NaCl Nanoparticles Using THz Spectroscopy. J Am Chem Soc 2018; 140:13793-13797. [PMID: 30351129 DOI: 10.1021/jacs.8b07828] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Sodium chloride (NaCl) aqueous solution becomes NaCl hydrate, NaCl·2H2O, at low temperature, which is different from potassium chloride and is a typical complex model for studying the freeze-drying process in foods and pharmaceuticals. Here, we detected unit-cell-sized NaCl particles in ice as precursor substances of NaCl·2H2O during freezing of NaCl solution by using terahertz (THz) spectroscopy. In the freezing process, Na+ and Cl- ions form two types of metastable unit-cell-sized NaCl particles on the pathway to the well-known NaCl·2H2O crystal production, which are not listed in the phase diagram of freezing of NaCl solution but have absorption peaks in THz spectra. This finding of single unit-cell-sized particles signifies the importance of studying the freeze-drying process in-depth and offers a new possibility for the development of freeze-drying technology for the manufacture of nanometer-sized particles such as ultrafine pharmaceutical powders, which more readily dissolve in water.
Collapse
|
28
|
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.
Collapse
|
29
|
Olivier L, Franchoo S, Niikura M, Vajta Z, Sohler D, Doornenbal P, Obertelli A, Tsunoda Y, Otsuka T, Authelet G, Baba H, Calvet D, Château F, Corsi A, Delbart A, Gheller JM, Gillibert A, Isobe T, Lapoux V, Matsushita M, Momiyama S, Motobayashi T, Otsu H, Péron C, Peyaud A, Pollacco EC, Roussé JY, Sakurai H, Santamaria C, Sasano M, Shiga Y, Takeuchi S, Taniuchi R, Uesaka T, Wang H, Yoneda K, Browne F, Chung LX, Dombradi Z, Flavigny F, Giacoppo F, Gottardo A, Hadyńska-Klęk K, Korkulu Z, Koyama S, Kubota Y, Lee J, Lettmann M, Louchart C, Lozeva R, Matsui K, Miyazaki T, Nishimura S, Ogata K, Ota S, Patel Z, Sahin E, Shand C, Söderström PA, Stefan I, Steppenbeck D, Sumikama T, Suzuki D, Werner V, Wu J, Xu Z. Erratum: Persistence of the Z=28 Shell Gap Around ^{78}Ni: First Spectroscopy of ^{79}Cu [Phys. Rev. Lett. 119, 192501 (2017)]. PHYSICAL REVIEW LETTERS 2018; 121:099902. [PMID: 30230867 DOI: 10.1103/physrevlett.121.099902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Indexed: 06/08/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.119.192501.
Collapse
|
30
|
Tarasov OB, Ahn DS, Bazin D, Fukuda N, Gade A, Hausmann M, Inabe N, Ishikawa S, Iwasa N, Kawata K, Komatsubara T, Kubo T, Kusaka K, Morrissey DJ, Ohtake M, Otsu H, Portillo M, Sakakibara T, Sakurai H, Sato H, Sherrill BM, Shimizu Y, Stolz A, Sumikama T, Suzuki H, Takeda H, Thoennessen M, Ueno H, Yanagisawa Y, Yoshida K. Discovery of ^{60}Ca and Implications For the Stability of ^{70}Ca. PHYSICAL REVIEW LETTERS 2018; 121:022501. [PMID: 30085743 DOI: 10.1103/physrevlett.121.022501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 06/11/2018] [Indexed: 06/08/2023]
Abstract
The discovery of the important neutron-rich nucleus _{20}^{60}Ca_{40} and seven others near the limits of nuclear stability is reported from the fragmentation of a 345 MeV/u ^{70}Zn projectile beam on ^{9}Be targets at the radioactive ion-beam factory of the RIKEN Nishina Center. The produced fragments were analyzed and unambiguously identified using the BigRIPS two-stage in-flight separator. The eight new neutron-rich nuclei discovered, ^{47}P, ^{49}S, ^{52}Cl, ^{54}Ar, ^{57}K, ^{59,60}Ca, and ^{62}Sc, are the most neutron-rich isotopes of the respective elements. In addition, one event consistent with ^{59}K was registered. The results are compared with the drip lines predicted by a variety of mass models and it is found that the models in best agreement with the observed limits of existence in the explored region tend to predict the even-mass Ca isotopes to be bound out to at least ^{70}Ca.
Collapse
|
31
|
Zhang G, Watanabe H, Kondev F, Lane G, Regan P, Söderström PA, Walker P, Kanaoka H, Korkulu Z, Lee P, Liu J, Nishimura S, Wu J, Yagi A, Ahn D, Alharbi T, Baba H, Browne F, Bruce A, Carroll R, Chae K, Dombradi Z, Doornenbal P, Estrade A, Fukuda N, Griffin C, Ideguchi E, Inabe N, Isobe T, Kanaya S, Kojouharov I, Kubo T, Kubono S, Kurz N, Kuti I, Lalkovski S, Lee C, Lee E, Lorusso G, Lotay G, Moon CB, Nishizuka I, Nita C, Odahara A, Patel Z, Phong V, Podolyák Z, Roberts O, Sakurai H, Schaffner H, Shand C, Shimizu Y, Sumikama T, Suzuki H, Takeda H, Terashima S, Vajta Z, Valiente-Dóbon J, Xu Z. β- γ and isomeric decay spectroscopy of 168Dy. EPJ WEB OF CONFERENCES 2018. [DOI: 10.1051/epjconf/201817802023] [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
This contribution will report on the experimental work on the level structure of 168Dy. The experimental data have been taken as part of the EURICA decay spectroscopy campaign at RIBF, RIKEN in November 2014. In the experiment, a 238U primary beam is accelerated up to 345 MeV/u with an average intensity of 12 pnA. The nuclei of interest are produced by in-flight fission of 238U impinging on Be target with a thickness of 5 mm. The excited states of 168Dy have been populated through the decay from a newly identified isomeric state and via the β decay from 168Tb. In this contribution, scientific motivations, experimental procedure and some preliminary results for this study are presented.
Collapse
|
32
|
Kalathingal M, Sumikama T, Mori T, Oiki S, Saito S. Structure and dynamics of solvent molecules inside the polytheonamide B channel in different environments: a molecular dynamics study. Phys Chem Chem Phys 2018; 20:3334-3348. [DOI: 10.1039/c7cp06299k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The β6.3-helical channel of the marine cytotoxic peptide, polytheonamide B (pTB), is examined in water, the POPC bilayer, and a 1 : 1 chloroform/methanol mixture using all-atom molecular dynamics simulations.
Collapse
|
33
|
Suzuki H, Sinclair L, Söderström PA, Lorusso G, Davies P, Ferreira LS, Maglione E, Wadsworth R, Wu J, Xu ZY, Nishimura S, Doornenbal P, Ahn DS, Browne F, Fukuda N, Inabe N, Kubo T, Lubos D, Patel Z, Rice S, Shimizu Y, Takeda H, Baba H, Estrade A, Fang Y, Henderson J, Isobe T, Jenkins D, Kubono S, Li Z, Nishizuka I, Sakurai H, Schury P, Sumikama T, Watanabe H, Werner V. Discovery of ^{72}Rb: A Nuclear Sandbank Beyond the Proton Drip Line. PHYSICAL REVIEW LETTERS 2017; 119:192503. [PMID: 29219499 DOI: 10.1103/physrevlett.119.192503] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Indexed: 06/07/2023]
Abstract
In this Letter, the observation of two previously unknown isotopes is presented for the first time: ^{72}Rb with 14 observed events and ^{77}Zr with one observed event. From the nonobservation of the less proton-rich nucleus ^{73}Rb, we derive an upper limit for the ground-state half-life of 81 ns, consistent with the previous upper limit of 30 ns. For ^{72}Rb, we have measured a half-life of 103(22) ns. This observation of a relatively long-lived odd-odd nucleus, ^{72}Rb, with a less exotic odd-even neighbor, ^{73}Rb, being unbound shows the diffuseness of the proton drip line and the possibility of sandbanks to exist beyond it. The ^{72}Rb half-life is consistent with a 5^{+}→5/2^{-} proton decay with an energy of 800-900 keV, in agreement with the atomic mass evaluation proton-separation energy as well as results from the finite-range droplet model and shell model calculations using the GXPF1A interaction. However, we cannot explicitly exclude the possibility of a proton transition between 9^{+}(^{72}Rb)→9/2^{+}(^{71}Kr) isomeric states with a broken mirror symmetry. These results imply that ^{72}Kr is a strong waiting point in x-ray burst rp-process scenarios.
Collapse
|
34
|
Olivier L, Franchoo S, Niikura M, Vajta Z, Sohler D, Doornenbal P, Obertelli A, Tsunoda Y, Otsuka T, Authelet G, Baba H, Calvet D, Château F, Corsi A, Delbart A, Gheller JM, Gillibert A, Isobe T, Lapoux V, Matsushita M, Momiyama S, Motobayashi T, Otsu H, Péron C, Peyaud A, Pollacco EC, Roussé JY, Sakurai H, Santamaria C, Sasano M, Shiga Y, Takeuchi S, Taniuchi R, Uesaka T, Wang H, Yoneda K, Browne F, Chung LX, Dombradi Z, Flavigny F, Giacoppo F, Gottardo A, Hadyńska-Klęk K, Korkulu Z, Koyama S, Kubota Y, Lee J, Lettmann M, Louchart C, Lozeva R, Matsui K, Miyazaki T, Nishimura S, Ogata K, Ota S, Patel Z, Sahin E, Shand C, Söderström PA, Stefan I, Steppenbeck D, Sumikama T, Suzuki D, Werner V, Wu J, Xu Z. Persistence of the Z=28 Shell Gap Around ^{78}Ni: First Spectroscopy of ^{79}Cu. PHYSICAL REVIEW LETTERS 2017; 119:192501. [PMID: 29219515 DOI: 10.1103/physrevlett.119.192501] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Indexed: 06/07/2023]
Abstract
In-beam γ-ray spectroscopy of ^{79}Cu is performed at the Radioactive Isotope Beam Factory of RIKEN. The nucleus of interest is produced through proton knockout from a ^{80}Zn beam at 270 MeV/nucleon. The level scheme up to 4.6 MeV is established for the first time and the results are compared to Monte Carlo shell-model calculations. We do not observe significant knockout feeding to the excited states below 2.2 MeV, which indicates that the Z=28 gap at N=50 remains large. The results show that the ^{79}Cu nucleus can be described in terms of a valence proton outside a ^{78}Ni core, implying the magic character of the latter.
Collapse
|
35
|
Sahin E, Bello Garrote FL, Tsunoda Y, Otsuka T, de Angelis G, Görgen A, Niikura M, Nishimura S, Xu ZY, Baba H, Browne F, Delattre MC, Doornenbal P, Franchoo S, Gey G, Hadyńska-Klȩk K, Isobe T, John PR, Jung HS, Kojouharov I, Kubo T, Kurz N, Li Z, Lorusso G, Matea I, Matsui K, Mengoni D, Morfouace P, Napoli DR, Naqvi F, Nishibata H, Odahara A, Sakurai H, Schaffner H, Söderström PA, Sohler D, Stefan IG, Sumikama T, Suzuki D, Taniuchi R, Taprogge J, Vajta Z, Watanabe H, Werner V, Wu J, Yagi A, Yalcinkaya M, Yoshinaga K. Shell Evolution towards ^{78}Ni: Low-Lying States in ^{77}Cu. PHYSICAL REVIEW LETTERS 2017; 118:242502. [PMID: 28665637 DOI: 10.1103/physrevlett.118.242502] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Indexed: 06/07/2023]
Abstract
The level structure of the neutron-rich ^{77}Cu nucleus is investigated through β-delayed γ-ray spectroscopy at the Radioactive Isotope Beam Factory of the RIKEN Nishina Center. Ions of ^{77}Ni are produced by in-flight fission, separated and identified in the BigRIPS fragment separator, and implanted in the WAS3ABi silicon detector array, surrounded by Ge cluster detectors of the EURICA array. A large number of excited states in ^{77}Cu are identified for the first time by correlating γ rays with the β decay of ^{77}Ni, and a level scheme is constructed by utilizing their coincidence relationships. The good agreement between large-scale Monte Carlo shell model calculations and experimental results allows for the evaluation of the single-particle structure near ^{78}Ni and suggests a single-particle nature for both the 5/2_{1}^{-} and 3/2_{1}^{-} states in ^{77}Cu, leading to doubly magic ^{78}Ni.
Collapse
|
36
|
Wu J, Nishimura S, Lorusso G, Möller P, Ideguchi E, Regan PH, Simpson GS, Söderström PA, Walker PM, Watanabe H, Xu ZY, Baba H, Browne F, Daido R, Doornenbal P, Fang YF, Gey G, Isobe T, Lee PS, Liu JJ, Li Z, Korkulu Z, Patel Z, Phong V, Rice S, Sakurai H, Sinclair L, Sumikama T, Tanaka M, Yagi A, Ye YL, Yokoyama R, Zhang GX, Alharbi T, Aoi N, Bello Garrote FL, Benzoni G, Bruce AM, Carroll RJ, Chae KY, Dombradi Z, Estrade A, Gottardo A, Griffin CJ, Kanaoka H, Kojouharov I, Kondev FG, Kubono S, Kurz N, Kuti I, Lalkovski S, Lane GJ, Lee EJ, Lokotko T, Lotay G, Moon CB, Nishibata H, Nishizuka I, Nita CR, Odahara A, Podolyák Z, Roberts OJ, Schaffner H, Shand C, Taprogge J, Terashima S, Vajta Z, Yoshida S. 94 β-Decay Half-Lives of Neutron-Rich _{55}Cs to _{67}Ho: Experimental Feedback and Evaluation of the r-Process Rare-Earth Peak Formation. PHYSICAL REVIEW LETTERS 2017; 118:072701. [PMID: 28256889 DOI: 10.1103/physrevlett.118.072701] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Indexed: 06/06/2023]
Abstract
The β-decay half-lives of 94 neutron-rich nuclei ^{144-151}Cs, ^{146-154}Ba, ^{148-156}La, ^{150-158}Ce, ^{153-160}Pr, ^{156-162}Nd, ^{159-163}Pm, ^{160-166}Sm, ^{161-168}Eu, ^{165-170}Gd, ^{166-172}Tb, ^{169-173}Dy, ^{172-175}Ho, and two isomeric states ^{174m}Er, ^{172m}Dy were measured at the Radioactive Isotope Beam Factory, providing a new experimental basis to test theoretical models. Strikingly large drops of β-decay half-lives are observed at neutron-number N=97 for _{58}Ce, _{59}Pr, _{60}Nd, and _{62}Sm, and N=105 for _{63}Eu, _{64}Gd, _{65}Tb, and _{66}Dy. Features in the data mirror the interplay between pairing effects and microscopic structure. r-process network calculations performed for a range of mass models and astrophysical conditions show that the 57 half-lives measured for the first time play an important role in shaping the abundance pattern of rare-earth elements in the solar system.
Collapse
|
37
|
Sumikama T, Oiki S. K + Occupancy in the Cavity Determines the Ion Permeation Rate through the KV1.2 Channel. Biophys J 2017. [DOI: 10.1016/j.bpj.2016.11.2931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
38
|
Tolosa-Delgado A, Agramunt J, Ahn DS, Algora A, Baba H, Bae S, Brewer NT, Caballero Folch R, Calvino F, Coleman-Smith PJ, Cortes G, Davinson T, Dillmann I, Domingo-Pardo C, Estrade A, Fukuda N, Go S, Griffin CJ, Grzywacz R, Ha J, Hall O, Harkness-Brennan L, Isobe T, Kahl D, Kiss GG, Kogimtzis M, Kubono S, Labiche M, Lazarus I, Lee J, Liu J, Lorusso G, Matsui K, Miernik K, Montes F, Moon B, Morales A, Nepal N, Nishimura S, Page RD, Phong VH, Podolyak Z, Pucknell VFE, Rasco BC, Regan P, Riego A, Rubio B, Rykaczewski K, Saito Y, Sakurai H, Shimizu Y, Simpson J, Söderström PA, Stracener DW, Sumikama T, Suzuki H, Tain JL, Takechi M, Takeda H, Tarifeño-Saldivia A, Thomas SL, Woods P. Commissioning of the BRIKEN beta-delayed neutron detector for the study of exotic neutron-rich nuclei. EPJ WEB OF CONFERENCES 2017. [DOI: 10.1051/epjconf/201716501051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
39
|
Gurgi L, Regan P, Söderström PA, Watanabe H, Walker P, Podolyák Z, Nishimura S, Berry T, Doornenbal P, Lorusso G, Isobe T, Baba H, Xu Z, Sakurai H, Sumikama T, Catford W, Bruce A, Browne F, Lane G, Kondev F, Odahara A, Wu J, Liu H, Xu F, Korkulu Z, Lee P, Liu J, Phong V, Yagi A, Zhang G, Alharbi T, Carroll R, Chae K, Dombradi Z, Estrade A, Fukuda N, Griffin C, Ideguchi E, Inabe N, Kanaoka H, Kojouharov I, Kubo T, Kubono S, Kurz N, Kuti I, Lalkovski S, Lee E, Lee C, Lotay G, Moon C, Nishizuka I, Nita C, Patel Z, Roberts O, Schaffner H, Shand C, Suzuki H, Takeda H, Terashima S, Vajta Z, Kanaya S, Valiente-Dobòn J. Isomer-delayed gamma-ray spectroscopy of neutron-rich 166Tb. EPJ WEB OF CONFERENCES 2017. [DOI: 10.1051/epjconf/201714610009] [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
|
40
|
Goigoux T, Ascher P, Blank B, Gerbaux M, Giovinazzo J, Grévy S, Kurtukian Nieto T, Magron C, Doornenbal P, Kiss GG, Nishimura S, Söderström PA, Phong VH, Wu J, Ahn DS, Fukuda N, Inabe N, Kubo T, Kubono S, Sakurai H, Shimizu Y, Sumikama T, Suzuki H, Takeda H, Agramunt J, Algora A, Guadilla V, Montaner-Piza A, Morales AI, Orrigo SEA, Rubio B, Fujita Y, Tanaka M, Gelletly W, Aguilera P, Molina F, Diel F, Lubos D, de Angelis G, Napoli D, Borcea C, Boso A, Cakirli RB, Ganioglu E, Chiba J, Nishimura D, Oikawa H, Takei Y, Yagi S, Wimmer K, de France G, Go S, Brown BA. Two-Proton Radioactivity of ^{67}Kr. PHYSICAL REVIEW LETTERS 2016; 117:162501. [PMID: 27792367 DOI: 10.1103/physrevlett.117.162501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Indexed: 06/06/2023]
Abstract
In an experiment with the BigRIPS separator at the RIKEN Nishina Center, we observed two-proton (2p) emission from ^{67}Kr. At the same time, no evidence for 2p emission of ^{59}Ge and ^{63}Se, two other potential candidates for this exotic radioactivity, could be observed. This observation is in line with Q value predictions which pointed to ^{67}Kr as being the best new candidate among the three for two-proton radioactivity. ^{67}Kr is only the fourth 2p ground-state emitter to be observed with a half-life of the order of a few milliseconds. The decay energy was determined to be 1690(17) keV, the 2p emission branching ratio is 37(14)%, and the half-life of ^{67}Kr is 7.4(30) ms.
Collapse
|
41
|
Patel Z, Podolyák Z, Walker PM, Regan PH, Söderström PA, Watanabe H, Ideguchi E, Simpson GS, Nishimura S, Browne F, Doornenbal P, Lorusso G, Rice S, Sinclair L, Sumikama T, Wu J, Xu ZY, Aoi N, Baba H, Bello Garrote FL, Benzoni G, Daido R, Dombrádi Z, Fang Y, Fukuda N, Gey G, Go S, Gottardo A, Inabe N, Isobe T, Kameda D, Kobayashi K, Kobayashi M, Komatsubara T, Kojouharov I, Kubo T, Kurz N, Kuti I, Li Z, Liu HL, Matsushita M, Michimasa S, Moon CB, Nishizuka H, Nishizuka I, Odahara A, Şahin E, Sakurai H, Schaffner H, Suzuki H, Takeda H, Tanaka M, Taprogge J, Vajta Z, Xu FR, Yagi A, Yokoyama R. β-decay spectroscopy of neutron-rich160,161,162Sm isotopes. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201612302002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
42
|
Sumikama T, Oiki S. Digitalized K+ Occupancy in the Nanocavity Holds and Releases Queues of K+ in a Channel. J Am Chem Soc 2016; 138:10284-92. [DOI: 10.1021/jacs.6b05270] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
43
|
Sumikama T. Origin of the Shape of Current-Voltage Curve through Nanopores: A Molecular Dynamics Study. Sci Rep 2016; 6:25750. [PMID: 27167118 PMCID: PMC4863172 DOI: 10.1038/srep25750] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 04/22/2016] [Indexed: 12/25/2022] Open
Abstract
Ion transports through ion channels, biological nanopores, are essential for life: Living cells generate electrical signals by utilizing ion permeation through channels. The measured current-voltage (i-V) relations through most ion channels are sublinear, however, its physical meaning is still elusive. Here we calculated the i-V curves through anion-doped carbon nanotubes, a model of an ion channel, using molecular dynamics simulation. It was found the i-V curve reflects the physical origin of the rate-determining step: the i-V curve is sublinear when the permeation is entropy bottlenecked, while it is superlinear in the case of the energy bottlenecked permeation. Based on this finding, we discuss the relation between the molecular mechanism of ion permeation through the biological K+ channels and the shape of the i-V curves through them. This work also provides a clue for a novel design of nanopores that show current rectification.
Collapse
|
44
|
Čeliković I, Lewitowicz M, Gernhäuser R, Krücken R, Nishimura S, Sakurai H, Ahn DS, Baba H, Blank B, Blazhev A, Boutachkov P, Browne F, de France G, Doornenbal P, Faestermann T, Fang Y, Fukuda N, Giovinazzo J, Goel N, Górska M, Ilieva S, Inabe N, Isobe T, Jungclaus A, Kameda D, Kim YK, Kwon YK, Kojouharov I, Kubo T, Kurz N, Lorusso G, Lubos D, Moschner K, Murai D, Nishizuka I, Park J, Patel Z, Rajabali M, Rice S, Schaffner H, Shimizu Y, Sinclair L, Söderström PA, Steiger K, Sumikama T, Suzuki H, Takeda H, Wang Z, Watanabe H, Wu J, Xu Z. New Isotopes and Proton Emitters-Crossing the Drip Line in the Vicinity of ^{100}Sn. PHYSICAL REVIEW LETTERS 2016; 116:162501. [PMID: 27152796 DOI: 10.1103/physrevlett.116.162501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Indexed: 06/05/2023]
Abstract
Several new isotopes, ^{96}In, ^{94}Cd, ^{92}Ag, and ^{90}Pd, have been identified at the RIKEN Nishina Center. The study of proton drip-line nuclei in the vicinity of ^{100}Sn led to the discovery of new proton emitters ^{93}Ag and ^{89}Rh with half-lives in the submicrosecond range. The systematics of the half-lives of odd-Z nuclei with T_{z}=-1/2 toward ^{99}Sn shows a stabilizing effect of the Z=50 shell closure. Production cross sections for nuclei in the vicinity of ^{100}Sn measured at different energies and target thicknesses were compared to the cross sections calculated by epax taking into account contributions of secondary reactions in the primary target.
Collapse
|
45
|
Wu J, Nishimura S, Lorusso G, Xu Z, Ideguchi E, Simpson G, Baba H, Browne F, Daido R, Doornebal P, Fang Y, Isobe T, Li Z, Patel Z, Rice S, Sinclair L, Söderström PA, Sumikama T, Watanabe H, Yagi A, Yokoyama R, Aoi N, Garrote FB, Benzoni G, Gey G, Gottardo A, Nishibata H, Odahara A, Sakurai H, Tanaka M, Taprogge J, Yamamoto T. β-decay half-lives of neutron-rich nuclei around158Nd, relevant to the formation of the A≈165 rare-earth element peak. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201610908003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
46
|
Werner V, Santamaria C, Louchart C, Obertelli A, Doornenbal P, Nowacki F, Authelet G, Baba H, Calvet D, Château F, Corsi A, Delbart A, Gheller JM, Gillibert A, Isobe T, Lapoux V, Matsushita M, Momiyama S, Motobayashi T, Niikura M, Otsu H, Péron C, Peyaud A, Pollacco E, Roussé JY, Sakurai H, Sasano M, Shiga Y, Takeuchi S, Taniuchi R, Uesaka T, Wang H, Yoneda K, Browne F, Chung L, Dombradi Z, Franchoo S, Giacoppo F, Gottardo A, Hadynska-Klek K, Korkulu Z, Koyama S, Kubota Y, Lee J, Lettmann M, Lozeva R, Matsui K, Miyazaki T, Nishimura S, Olivier L, Ota S, Patel Z, Pietralla N, Sahin E, Shand C, Söderström PA, Stefan I, Steppenbeck D, Sumikama T, Suzuki D, Vajta Z, Wu J, Xu Z. Collectivity of neutron-rich Cr and Fe toward N=50. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201610703007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
47
|
Sasano M, Yasuda J, Zegers RGT, Baba H, Chao W, Dozono M, Fukuda N, Inabe N, Isobe T, Jhang G, Kamaeda D, Kubo T, Kurata-Nishimura M, Milman E, Motobayashi T, Otsu H, Panin V, Powell W, Sakai H, Sako M, Sato H, Shimizu Y, Stuhl L, Suzuki H, Tangwancharoen S, Takeda H, Uesaka T, Yoneda K, Zenihiro J, Kobayashi T, Sumikama T, Tako T, Nakamura T, Kondo Y, Togano Y, Shikata M, Tsubota J, Yako K, Shimoura K, Ota S, Kawase S, Kubota Y, Takaki M, Michimasa S, Kisamori K, Lee C, Tokieda H, Kobayashi M, Koyama S, Kobayashi N, Wakasa T, Sakaguchi S, Krasznahorkay A, Murakami T, Nakatsuka N, Kaneko M, Matsuda Y, Mucher D, Reichert S, Bazin D, Lee J. Study of Gamow-Teller transitions from 132Sn via the ( p, n) reaction at 220 MeV/u in inverse kinematics. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201610706003] [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
|
48
|
Santamaria C, Louchart C, Obertelli A, Werner V, Doornenbal P, Nowacki F, Authelet G, Baba H, Calvet D, Château F, Corsi A, Delbart A, Gheller JM, Gillibert A, Isobe T, Lapoux V, Matsushita M, Momiyama S, Motobayashi T, Niikura M, Otsu H, Péron C, Peyaud A, Pollacco EC, Roussé JY, Sakurai H, Sasano M, Shiga Y, Takeuchi S, Taniuchi R, Uesaka T, Wang H, Yoneda K, Browne F, Chung LX, Dombradi Z, Franchoo S, Giacoppo F, Gottardo A, Hadynska-Klek K, Korkulu Z, Koyama S, Kubota Y, Lee J, Lettmann M, Lozeva R, Matsui K, Miyazaki T, Nishimura S, Olivier L, Ota S, Patel Z, Pietralla N, Sahin E, Shand C, Söderström PA, Stefan I, Steppenbeck D, Sumikama T, Suzuki D, Vajta Z, Wu J, Xu Z. Extension of the N=40 Island of Inversion towards N=50: Spectroscopy of (66)Cr, (70,72)Fe. PHYSICAL REVIEW LETTERS 2015; 115:192501. [PMID: 26588374 DOI: 10.1103/physrevlett.115.192501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Indexed: 06/05/2023]
Abstract
We report on the measurement of the first 2(+) and 4(+) states of (66)Cr and (70,72)Fe via in-beam γ-ray spectroscopy. The nuclei of interest were produced by (p,2p) reactions at incident energies of 260 MeV/nucleon. The experiment was performed at the Radioactive Isotope Beam Factory, RIKEN, using the DALI 2γ-ray detector array and the novel MINOS device, a thick liquid hydrogen target combined with a vertex tracker. A low-energy plateau of 2(1)(+) and 4(1)(+) energies as a function of the neutron number was observed for N≥38 and N≥40 for even-even Cr and Fe isotopes, respectively. State-of-the-art shell model calculations with a modified Lenzi-Nowacki-Poves-Sieja (LNPS) interaction in the pfg(9/2)d(5/2) valence space reproduce the observations. Interpretation within the shell model shows an extension of the island of inversion at N=40 for more neutron-rich isotopes towards N=50.
Collapse
|
49
|
Moschner K, Blazhev A, Warr N, Boutachkov P, Davies P, Wadsworth R, Ameil F, Baba H, Bäck T, Dewald M, Doornenbal P, Faestermann T, Gengelbach A, Gerl J, Gernhäuser R, Go S, Górska M, Grawe H, Gregor E, Hotaka H, Isobe T, Jenkins DG, Jolie J, Jung HS, Kojouharov I, Kurz N, Lewitowicz M, Lorusso G, Merchan E, Naqvi F, Nishibata H, Nishimura D, Nishimura S, Pietralla N, Schaffner H, Söderström PA, Steiger K, Sumikama T, Taprogge J, Thöle P, Watanabe H, Werner V, Xu ZY, Yagi A, Yoshinaga K, Zhu Y. Study of ground and excited state decays inN≈ZAg nuclei. EPJ WEB OF CONFERENCES 2015. [DOI: 10.1051/epjconf/20159301024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
50
|
Lorusso G, Nishimura S, Xu ZY, Jungclaus A, Shimizu Y, Simpson GS, Söderström PA, Watanabe H, Browne F, Doornenbal P, Gey G, Jung HS, Meyer B, Sumikama T, Taprogge J, Vajta Z, Wu J, Baba H, Benzoni G, Chae KY, Crespi FCL, Fukuda N, Gernhäuser R, Inabe N, Isobe T, Kajino T, Kameda D, Kim GD, Kim YK, Kojouharov I, Kondev FG, Kubo T, Kurz N, Kwon YK, Lane GJ, Li Z, Montaner-Pizá A, Moschner K, Naqvi F, Niikura M, Nishibata H, Odahara A, Orlandi R, Patel Z, Podolyák Z, Sakurai H, Schaffner H, Schury P, Shibagaki S, Steiger K, Suzuki H, Takeda H, Wendt A, Yagi A, Yoshinaga K. β-Decay Half-Lives of 110 Neutron-Rich Nuclei across the N=82 Shell Gap: Implications for the Mechanism and Universality of the Astrophysical r Process. PHYSICAL REVIEW LETTERS 2015; 114:192501. [PMID: 26024165 DOI: 10.1103/physrevlett.114.192501] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Indexed: 06/04/2023]
Abstract
The β-decay half-lives of 110 neutron-rich isotopes of the elements from _{37}Rb to _{50}Sn were measured at the Radioactive Isotope Beam Factory. The 40 new half-lives follow robust systematics and highlight the persistence of shell effects. The new data have direct implications for r-process calculations and reinforce the notion that the second (A≈130) and the rare-earth-element (A≈160) abundance peaks may result from the freeze-out of an (n,γ)⇄(γ,n) equilibrium. In such an equilibrium, the new half-lives are important factors determining the abundance of rare-earth elements, and allow for a more reliable discussion of the r process universality. It is anticipated that universality may not extend to the elements Sn, Sb, I, and Cs, making the detection of these elements in metal-poor stars of the utmost importance to determine the exact conditions of individual r-process events.
Collapse
|