Synthesis of nuclei of the superheavy element 114 in reactions induced by 48Ca

被引:426
作者
Oganessian, YT
Yeremin, AV [1 ]
Popeko, AG
Bogomolov, SL
Buklanov, GV
Chelnokov, ML
Chepigin, VI
Gikal, BN
Gorshkov, VA
Gulbekian, GG
Itkis, MG
Kabachenko, AP
Lavrentev, AY
Malyshev, ON
Rohac, J
Sagaidak, RN
Hofmann, S
Saro, S
Giardina, G
Morita, K
机构
[1] Joint Inst Nucl Res, Flerov Lab Nucl React, Dubna 141980, Russia
[2] Gesell Schwerionenforsch GmbH, D-64291 Darmstadt, Germany
[3] Comenius Univ, Dept Phys, SK-84215 Bratislava, Slovakia
[4] Univ Messina, Dipartimento Fis, I-98166 Messina, Italy
[5] RIKEN, Inst Phys & Chem Res, Wako, Saitama 35101, Japan
关键词
D O I
10.1038/22281
中图分类号
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号
07 ; 0710 ; 09 ;
摘要
The stability of heavy nuclides, which tend to decay by cy-emission and spontaneous fission, is determined by the structural properties of nuclear matter. Nuclear binding energies and lifetimes increase markedly in the vicinity of closed shells of neutrons or protons (nucleons), corresponding to 'magic' numbers of nucleons; these give rise to the most stable (spherical) nuclear shapes in the ground state. For example, with a proton number of Z = 82 and a neutron number of N = 126, the nucleus Pb-208 is 'doubly-magic' and also exceptionally stable, The next closed neutron shell is expected at N = 184, leading to the prediction of an 'island of stability' of superheavy nuclei, for a broad range of isotopes with Z = 104 to 120 (refs 1, 2), The heaviest known nuclei have lifetimes of less than a millisecond, but nuclei near the top of the island of stability are predicted to exist for many years. (In contrast, nuclear matter consisting of about 300 nucleons with no shell structure would undergo fission within about 10(-20) seconds.) Calculations(3-5) indicate that nuclei with N > 168 should already benefit from the stabilizing influence of the closed shell at N = 184. Here we report the synthesis of an isotope containing 114 protons and 173 neutrons, through fusion of intense beams of Ca-48 ions with Pu-242 targets. The isotope decays by or-emission with a half-life of about five seconds, providing experimental confirmation of the island of stability.
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页码:242 / 245
页数:4
相关论文
共 21 条
  • [1] ATTEMPTS TO PRODUCE SUPERHEAVY ELEMENTS BY FUSION OF CA-48 WITH CM-248 IN THE BOMBARDING ENERGY-RANGE OF 4.5-5.2 MEV/U
    ARMBRUSTER, P
    AGARWAL, YK
    BRUCHLE, W
    BRUGGER, M
    DUFOUR, JP
    GAGGELER, H
    HESSBERGER, FP
    HOFMANN, S
    LEMMERTZ, P
    MUNZENBERG, G
    POPPENSIEKER, K
    REISDORF, W
    SCHADEL, M
    SCHMIDT, KH
    SCHNEIDER, JHR
    SCHNEIDER, WFW
    SUMMERER, K
    VERMEULEN, D
    WIRTH, G
    GHIORSO, A
    GREGORICH, KE
    LEE, D
    LEINO, M
    MOODY, KJ
    SEABORG, GT
    WELCH, RB
    WILMARTH, P
    YASHITA, S
    FRINK, C
    GREULICH, N
    HERRMANN, G
    HICKMANN, U
    HILDEBRAND, N
    KRATZ, JV
    TRAUTMANN, N
    FOWLER, MM
    HOFFMAN, DC
    DANIELS, WR
    VONGUNTEN, HR
    DORNHOFER, H
    [J]. PHYSICAL REVIEW LETTERS, 1985, 54 (05) : 406 - 409
  • [2] DYNAMIC HINDRANCE TO COMPOUND NUCLEUS FORMATION IN HEAVY-ION REACTIONS
    BLOCKI, JP
    FELDMEIER, H
    SWIATECKI, WJ
    [J]. NUCLEAR PHYSICS A, 1986, 459 (01) : 145 - 172
  • [3] 1ST CONFIRMATION OF THE DISCOVERY OF ELEMENT-106
    GREGORICH, KE
    LANE, MR
    MOHAR, MF
    LEE, DM
    KACHER, CD
    SYLWESTER, ER
    HOFFMAN, DC
    [J]. PHYSICAL REVIEW LETTERS, 1994, 72 (10) : 1423 - 1426
  • [4] Hofmann S, 1996, Z PHYS A-HADRON NUCL, V354, P229, DOI 10.1007/s002180050036
  • [5] SEARCH FOR SUPERHEAVY ELEMENTS IN BOMBARDMENT OF CM-248 WITH CA-48
    HULET, EK
    LOUGHEED, RW
    WILD, JF
    LANDRUM, JH
    STEVENSON, PC
    GHIORSO, A
    NITSCHKE, JM
    OTTO, RJ
    MORRISSEY, DJ
    BAISDEN, PA
    GAVIN, BF
    LEE, D
    SILVA, RJ
    FOWLER, MM
    SEABORG, GT
    [J]. PHYSICAL REVIEW LETTERS, 1977, 39 (07) : 385 - 389
  • [6] KUTNER VB, 1998, P 15 INT C CYCL THEI, P405
  • [7] alpha decay of (273)110: Shell closure at N=162
    Lazarev, YA
    Lobanov, YV
    Oganessian, YT
    Utyonkov, VK
    Abdullin, FS
    Polyakov, AN
    Rigol, J
    Shirokovsky, IV
    Tsyganov, YS
    Iliev, S
    Subbotin, VG
    Sukhov, AM
    Buklanov, GV
    Gikal, BN
    Kutner, VB
    Mezentsev, AN
    Subotic, K
    Wild, JF
    Longheed, RW
    Moody, KJ
    [J]. PHYSICAL REVIEW C, 1996, 54 (02) : 620 - 625
  • [8] Nuclear properties for astrophysical and radioactive-ion-beam applications
    Moller, P
    Nix, JR
    Kratz, KL
    [J]. ATOMIC DATA AND NUCLEAR DATA TABLES, 1997, 66 (02) : 131 - 343
  • [9] NUCLEAR MASSES AND DEFORMATIONS
    MYERS, WD
    SWIATECK.WJ
    [J]. NUCLEAR PHYSICS, 1966, 81 (01): : 1 - &
  • [10] CALCULATION OF FISSION BARRIERS FOR HEAVY AND SUPERHEAVY NUCLEI
    NIX, JR
    [J]. ANNUAL REVIEW OF NUCLEAR AND PARTICLE SCIENCE, 1972, 22 : 65 - 120