検索対象:     
報告書番号:
※ 半角英数字
 年 ~ 
 年
検索結果: 56 件中 1件目~20件目を表示

発表形式

Initialising ...

選択項目を絞り込む

掲載資料名

Initialising ...

発表会議名

Initialising ...

筆頭著者名

Initialising ...

キーワード

Initialising ...

使用言語

Initialising ...

発行年

Initialising ...

開催年

Initialising ...

選択した検索結果をダウンロード

論文

Decay studies of new isomeric states in $$^{255}$$No

Bronis, A.*; He${ss}$berger, F. P.*; Antalic, S.*; Andel, B.*; Ackermann, D.*; Heinz, S.*; Hofmann, S.*; Khuyagbaatar, J.*; Kindler, B.*; Kojouharov, I.*; et al.

Physical Review C, 106(1), p.014602_1 - 014602_12, 2022/07

 被引用回数:2 パーセンタイル:47.44(Physics, Nuclear)

The decay of excited states in $$^{255}$$No was investigated by applying the evaporation-residue-conversion-electron correlation technique. Two new isomeric states were observed in $$^{255}$$No together with the previously known one. Excitation energies of the isomeric states were estimated based on the energies of conversion electrons and $$gamma$$ rays from correlation chains. These results were in accord with theoretical calculations based on the mean-field models. A tentative decay scheme of isomeric states in $$^{255}$$No is proposed, and their Nilsson configurations are discussed. The energy decrease of the 11/2$$^{-}$$[725] Nilsson level for heavy $$N$$=153 isotones as a function of increasing proton number is confirmed.

論文

$$alpha$$ decay of $$^{243}$$Fm$$_{143}$$ and $$^{245}$$Fm$$_{145}$$, and of their daughter nuclei

Khuyagbaatar, J.*; He${ss}$berger, F. P.*; Hofmann, S.*; Ackermann, D.*; Burkhard, H. G.*; Heinz, S.*; Kindler, B.*; Kojouharov, I.*; Lommel, B.*; Mann, R.*; et al.

Physical Review C, 102(4), p.044312_1 - 044312_8, 2020/10

 被引用回数:8 パーセンタイル:67.79(Physics, Nuclear)

Nuclear structure of $$^{243}$$Fm, $$^{245}$$Fm, and their daughter nuclei were investigated via detection of their radioactive decays, $$alpha$$, $$gamma$$, and spontaneous fission. Measured $$alpha$$-decay energies, half-lives, and branching ratios improve the literature data significantly. A signature for detection of the hitherto unknown $$^{235}$$Cm was found in the $$alpha$$-decay chains from $$^{243}$$Fm. Two groups of $$alpha$$ events with average energies of 6.69(2) MeV and 7.01(2) MeV and with a half-life of $$T_{1/2}$$ = 300$$^{+250}_{-100}$$, s are suggested to originate from $$^{235}$$Cm. Tentative decay schemes for $$^{243}$$Fm, $$^{239}$$Cf, $$^{235}$$Cm, and $$^{245}$$Fm, $$^{241}$$Cf isotopes are suggested based on the present experimental data. Systematical trends of single-particle states in $$N$$=141 isotones of $$Z$$ = 92-98 nuclei are discussed.

論文

Search for $$alpha$$ decay of $$^{104}$$Te with a novel recoil-decay scintillation detector

Xiao, Y.*; Go, S.*; Grzywacz, R.*; Orlandi, R.; Andreyev, A. N.; 浅井 雅人; Bentley, M. A.*; de Angelis, G.*; Gross, C. J.*; Hausladen, P.*; et al.

Physical Review C, 100(3), p.034315_1 - 034315_8, 2019/09

 被引用回数:16 パーセンタイル:83.79(Physics, Nuclear)

A search for super-allowed $$alpha$$ decay of N=Z nuclei $$^{104}$$Te and $$^{108}$$Xe was carried out using a novel recoil-decay scintillator detector at the tandem accelerator facility at Japan Atomic Energy Agency. Inorganic crystal scintillation material of YAP:Ce (Yttrium Aluminium Perovskite) coupled to position-sensitive photo-multiplier tube (PSPMT) was implemented for the first time in a radioactive decay experiment. Residues from the fusion-evaporation reaction $$^{58}$$Ni+$$^{54}$$Fe$$rightarrow$$ $$^{112}$$Xe$$^*$$ were separated by the JAEA Recoil Mass Separator (RMS) and implanted into the YAP:Ce crystal. $$alpha$$ decays of neutron-deficient tellurium isotopes were identified and proton-emission of $$^{109}$$I was observed. No conclusive evidence was found for the decay chain $$^{108}$$Xe$$rightarrow$$$$^{104}$$Te$$rightarrow$$ $$^{100}$$Sn within 3 days experiment. The cross section limit of 130 pb was obtained for production of two events of $$^{108}$$Xe, about an order of magnitude below the expectation based on earlier cross section measurements and HIVAP calculations.

論文

Population of nuclides with Z$$ge$$98 in multi-nucleon transfer reactions of $$^{48}$$Ca+$$^{248}$$Cm

Devaraja, H. M.*; Heinz, S.*; Beliuskina, O.*; Hofmann, S.*; Hornung, C.*; M$"u$nzenberg, G.*; Ackermann, D.*; Gupta, M.*; Gambhir, Y. K.*; Henderson, R. A.*; et al.

European Physical Journal A, 55(2), p.25_1 - 25_9, 2019/02

 被引用回数:12 パーセンタイル:76.08(Physics, Nuclear)

The results for nuclei above curium, produced in multi-nucleon transfer reactions of $$^{48}$$Ca+$$^{248}$$Cm at the velocity filter SHIP of GSI Darmstadt, are presented. Spontaneous fission and $$alpha$$ activities have been used to study the population of nuclei with lifetimes ranging from few milliseconds to several days. We observed several, relatively neutron-rich isotopes with atomic numbers Z $$ge$$ 98; among them a weak 224 millisecond activity which we tentatively attributed to $$^{260}$$No. The measured cross-sections of the observed nuclei give hope that multi-nucleon transfer reactions are a way to reach new neutron-rich heavy and superheavy nuclei, which are not accessible in other reactions. We compare our results with data from earlier experiments and discuss limitations and future perspectives of the method.

論文

Study of the reaction $$^{48}$$Ca + $$^{248}$$Cm $$rightarrow$$ $$^{296}$$Lv$$^{ast}$$ at RIKEN-GARIS

加治 大哉*; 森田 浩介*; 森本 幸司*; 羽場 宏光*; 浅井 雅人; 藤田 訓裕*; Gan, Z.*; Geissel, H.*; 長谷部 裕雄*; Hofmann, S.*; et al.

Journal of the Physical Society of Japan, 86(3), p.034201_1 - 034201_7, 2017/03

 被引用回数:27 パーセンタイル:81.68(Physics, Multidisciplinary)

理化学研究所のガス充填型反跳核分離装置GARISを用いて$$^{48}$$Ca + $$^{248}$$Cm $$rightarrow$$ $$^{296}$$Lv$$^{ast}$$融合反応を調べた。116番元素$$^{292}$$Lv, $$^{293}$$Lvと思われる核反応生成物に起因するアルファ線と自発核分裂の崩壊連鎖が7事象観測された。崩壊連鎖中に観測された原子核の性質は過去の報告値とよく一致したが、1つの崩壊連鎖で一部矛盾が観測された。これは$$^{285}$$Cnの新しい自発核分裂分岐比の存在、あるいは新同位体$$^{294}$$Lv生成の可能性を示唆するものと思われる。

論文

Review of even element super-heavy nuclei and search for element 120

Hofmann, S.*; Heinz, S.*; Mann, R.*; Maurer, J.*; M$"u$nzenberg, G.*; Antalic, S.*; Barth, W.*; Burkhard, K. G.*; Dahl, L.*; Eberhardt, K.*; et al.

European Physical Journal A, 52(6), p.180_1 - 180_34, 2016/06

 被引用回数:171 パーセンタイル:93.43(Physics, Nuclear)

The reaction $$^{54}$$Cr+$$^{248}$$Cm was investigated at the velocity filter SHIP at GSI with the intention to study production and decay properties of isotopes of element 120. Three correlated signals were measured, which occurred within a period of 279 ms. The heights of the signals correspond with the expectations for a decay sequence starting with an isotope of element 120. However, a complete decay chain cannot be established, since a signal from the implantation of the evaporation residue cannot be identified unambiguously. Measured properties of the event chain are discussed in detail. The result is compared with theoretical predictions. Previously measured decay properties of even element super-heavy nuclei were compiled in order to find arguments for an assignment from the systematics of experimental data. In the course of this review, a few tentatively assigned data could be corrected. New interpretations are given for results which could not be assigned definitely in previous studies. The discussion revealed that the cross-section for production of element 120 could be high enough so that a successful experiment seems possible with presently available techniques. However, a continuation of the experiment at SHIP for a necessary confirmation of the results obtained in a relatively short irradiation of five weeks is not possible at GSI presently. In the summary and outlook section we also present concepts for the continuation of research in the field of super-heavy nuclei.

論文

Short-lived isomers in $$^{192}$$Po and $$^{194}$$Po

Andel, B.*; Andreyev, A. N.; Antalic, S.*; He${ss}$berger, F. P.*; Ackermann, D.*; Hofmann, S.*; Huyse, M.*; Kalaninov$'a$, Z.*; Kindler, B.*; Kojouharov, I.*; et al.

Physical Review C, 93(6), p.064316_1 - 064316_12, 2016/06

 被引用回数:5 パーセンタイル:38.91(Physics, Nuclear)

Isomeric states in $$^{194}$$Po and $$^{192}$$Po were studied at the velocity filter SHIP. The isotopes were produced in the fusion-evaporation reactions $$^{141}$$Pr($$^{56}$$Fe, $$p2n$$)$$^{194}$$Po and $$^{144}$$Sm($$^{51}$$V, $$p2n$$)$$^{192}$$Po. Several new $$gamma$$-ray transitions were attributed to the isomers and $$gamma$$-$$gamma$$ coincidences for both isomers were studied for the first time. The 459-keV transition earlier, tentatively proposed as de-exciting the isomeric level in $$^{194}$$Po, was replaced by a new 248-keV transition, and the spin of this isomer was reassigned from (11$$^{-}$$) to (10$$^{-}$$). The de-excitation of the (11$$^{-}$$) isomeric level in $$^{192}$$Po by the 154-keV transition was confirmed and a parallel de-excitation by a 733-keV (E3) transition to (8$$^{+}$$) level of the ground-state band was suggested. Moreover, side feeding to the (4$$^{+}$$) level of the ground-state band was proposed. The paper also discusses strengths of transitions de-exciting 11$$^{-}$$ isomers in neighboring Po and Pb isotopes.

論文

Remarks on the fission barriers of super-heavy nuclei

Hofmann, S.*; Heinz, S.*; Mann, R.*; Maurer, J.*; M$"u$nzenberg, G.*; Antalic, S.*; Barth, W.*; Dahl, L.*; Eberhardt, K.*; Grzywacz, R.*; et al.

European Physical Journal A, 52(4), p.116_1 - 116_12, 2016/04

 被引用回数:29 パーセンタイル:87.47(Physics, Nuclear)

Shell-correction energies of super-heavy nuclei are approximated by using Q$$_{alpha}$$ values of measured decay chains. Five decay chains were analyzed, which start at the isotopes $$^{285}$$Fl, $$^{294}$$118, $$^{291}$$Lv, $$^{292}$$Lv and $$^{293}$$Lv. The data are compared with predictions of macroscopic-microscopic models. Fission barriers are estimated that can be used to eliminate uncertainties in partial fission half-lives and in calculations of evaporation-residue cross-sections. In that calculations, fission probability of the compound nucleus is a major factor contributing to the total cross-section. The data also provide constraints on the cross-sections of capture and quasi-fission in the entrance channel of the fusion reaction. Arguments are presented that fusion reactions for synthesis of isotopes of elements 118 and 120 may have higher cross-sections than assumed so far.

論文

Observation of new neutron-deficient isotopes with Z$$ge$$92 in multinucleon transfer reactions

Devaraja, H. M.*; Heinz, S.*; Beliuskina, O.*; Comas, V. F.*; Hofmann, S.*; Hornung, C.*; M$"u$nzenberg, G.*; 西尾 勝久; Ackermann, D.*; Gambhir, Y. K.*; et al.

Physics Letters B, 748, p.199 - 203, 2015/09

AA2015-0304.pdf:0.78MB

 被引用回数:66 パーセンタイル:96.93(Astronomy & Astrophysics)

In deep inelastic multinucleon transfer reactions of $$^{48}$$Ca +$$^{248}$$Cm we observed about 100 residual nuclei with proton numbers between Z =82 and Z =100. Among them, there are five new neutron-deficient isotopes: $$^{216}$$U, $$^{219}$$Np, $$^{223}$$Am, $$^{229}$$Am and $$^{233}$$Bk. As separator for the transfer products we used the velocity filter SHIP of GSI while the isotope identification was performed via the $$alpha$$-decay chains of the nuclei. These first results reveal that multinucleon transfer reactions together with here applied fast and sensitive separation and detection techniques are promising for the synthesis of new isotopes in the region of heaviest nuclei.

論文

Signature of the Z=82 shell closure in $$alpha$$-decay process

Andreyev, A. N.*; Huyse, M.*; Van Duppen, P.*; Qi, C.*; Liotta, R. J.*; Antalic, S.*; Ackermann, D.*; Franchoo, S.*; He${ss}$berger, F. P.*; Hofmann, S.*; et al.

Physical Review Letters, 110(24), p.242502_1 - 242502_5, 2013/06

 被引用回数:90 パーセンタイル:93.85(Physics, Multidisciplinary)

$$alpha$$-decay data for more than 20 nuclei of the most neutron-deificient isotopes in the region from lead to thorium was obtained. The combined analysis allowed us for the first time to clearly show that crossing the Z=82 shell to higher proton numbers strongly accelerates the $$alpha$$ decay. The analysis support the conjecture that both the N=126 and Z=82 shell closures stongly influence the $$alpha$$-formation probability.

論文

$$alpha$$-decay spectroscopy of the chain $$^{179}$$Tl$$^{g}$$ $$rightarrow$$ $$^{175}$$Au$$^{g}$$ $$rightarrow$$ $$^{171}$$Ir$$^{g}$$ $$rightarrow$$ $$^{167}$$Re$$^{m}$$

Andreyev, A. N.*; Liberati, V.*; Antalic, S.*; Ackermann, D.*; Barzakh, A.*; Bree, N.*; Cocolios, T. E.*; Diriken, J.*; Elseviers, J.*; Fedorov, D.*; et al.

Physical Review C, 87(5), p.054311_1 - 054311_8, 2013/05

 被引用回数:16 パーセンタイル:69.92(Physics, Nuclear)

$$alpha$$-decay studies of $$^{179}$$Tl$$^{g}$$ and its dahghter products $$^{175}$$Au$$^{g}$$ and $$^{171}$$Ir$$^{g}$$ were carried out in two complementary experiments at the mass separator ISOLDE (CERN) and velocity filter SHIP (GSI). The nucluesu $$^{175}$$Au$$^{g}$$ has $$alpha$$ decay properties of half-life 207 ms and $$alpha$$-decay energy 6433 keV. The ground state spins and parities for $$^{175}$$Au and $$^{171}$$Ir were determined to be 1/2$$^{+}$$.

論文

In-beam fissio study at JAEA for heavy element synthesis

西尾 勝久; 池添 博; Hofmann, S.*; Ackermann, D.*; 有友 嘉浩*; Comas, V. F.*; D$"u$llmann, Ch. E.*; Heinz, S.*; Heredia, J. A.*; He${ss}$berger, F. P.*; et al.

AIP Conference Proceedings 1524, p.68 - 72, 2013/04

 被引用回数:0 パーセンタイル:0.04(Physics, Nuclear)

Fission fragment mass and kinetic energies distributions were measured in the heavy-ion induced reactions using $$^{238}$$U target nucleus at the energies around the Coulomb barrier. We observed strong variation of the fragment mass distribution with incident energy, which was explained by an energy dependence of the probabilities for fusion and quasifission. A calculation based on a fluctuation-dissipation model was carried out to determine the fusion probability in the reactions of $$^{30}$$Si+$$^{238}$$U and $$^{34}$$S+$$^{238}$$U. The fusion probabilities were consistent with those determied from the evaporation residue cross sections for both reactions, showing that in-beam fission measurement and analysis can give a reasonable estimation for the cross sections to produce super-heavy nuclei. We also discss the results for in-beam fission measurement of $$^{48}$$Ca+$$^{238}$$U.

論文

$$beta$$-delayed fission of $$^{192,194}$$At

Andreyev, A. N.*; Antalic, S.*; Ackermann, D.*; Bianco, L.*; Franchoo, S.*; Heinz, S.*; He${ss}$berger, F. P.*; Hofmann, S.*; Huyse, M.*; Kalaninov$'a$, Z.*; et al.

Physical Review C, 87(1), p.014317_1 - 014317_8, 2013/01

 被引用回数:24 パーセンタイル:80.11(Physics, Nuclear)

By using the recoil-fission correlation technique, the exotic process of beta-delayed fission ($$beta$$DF) was unambiguously identified in the very neutron-deficient nuclei $$^{192,194}$$At in experiments at the velocity filter SHIP at Gesellschaft f$"u$r Schwerionenforschung (GSI). The upper limits for the total kinetic energy release in fission of $$^{194,196}$$Po, being the daughter of $$^{192,194}$$At after $$beta^{+}/EC$$ decay, were estimated. The possibility of an unusually high $$beta^{+}$$DF probability $$^{192}$$At is discussed.

論文

$$beta$$-delayed fission of $$^{186,188}$$Bi isotopes

Lane, J. F. W.*; Andreyev, A. N.*; Antalic, S.*; Ackermann, D.*; Gerl, J.*; He${ss}$berger, F. P.*; Hofmann, S.*; Huyse, M.*; Kettunen, H.*; Kleinb$"o$hl, A.*; et al.

Physical Review C, 87(1), p.014318_1 - 014318_7, 2013/01

 被引用回数:15 パーセンタイル:68.00(Physics, Nuclear)

By using the technique of correlating implanted evaporation residues and their subsequent fission decay, $$beta$$-delayed fission ($$beta$$DF) of $$^{186}$$Bi has been identified for the first time and $$beta$$DF of $$^{188}$$Bi has been unambiguously confirmed. The experiments were performed at the velocity filter SHIP (GSI, Darmstadt). The $$beta$$DF probabilities for both nuclides were qualitatively estimated, and, in particular indications for a large value in the case of $$^{186}$$Bi are regarded.

論文

Evidence for hindrance in fusion between sulfur and lead nuclei

Khuyagbaatar, J.*; 西尾 勝久; Hofmann, S.*; Ackermann, D.*; Block, M.*; Heinz, S.*; He${ss}$berger, F. P.*; 廣瀬 健太郎; 池添 博; Kindler, B.*; et al.

Physical Review C, 86(6), p.064602_1 - 064602_6, 2012/12

 被引用回数:25 パーセンタイル:76.85(Physics, Nuclear)

The influence of the structure of projectile and target nuclei on the capture cross-sections was investigated for the reactions $$^{34}$$S+$$^{204,206,208}$$Pb and $$^{36}$$S+$$^{204,206,208}$$Pb. Capture cross-sections were deduced by measuring the fission fragments using multi-wire proportional counters. An enhancement of the capture cross-sections relative to an one-dimensional barrier penetration model was observed for all reactions at energies below the interaction barriers. The enhancement is larger in the case of reactions with $$^{34}$$S than with $$^{36}$$S. This observation is explained by a stronger coupling to the vibrational states in the reactions with $$^{34}$$S. Comparing the capture cross-sections and the evaporation-residue cross-sections for the reactions $$^{36}$$S+$$^{206}$$Pb and $$^{34}$$S+$$^{208}$$Pb, both yielding the same compound nucleus $$^{242}$$Cf, it is shown that the latter reaction has a lower fusion probability.

論文

Fusion probabilities in the reactions $$^{40,48}$$Ca + $$^{238}$$U at energies around the Coulomb barrier

西尾 勝久; 光岡 真一; 西中 一朗; 牧井 宏之; 若林 泰生*; 池添 博; 廣瀬 健太郎*; 大槻 勤*; 有友 嘉浩*; Hofmann, S.*

Physical Review C, 86(3), p.034608_1 - 034608_6, 2012/09

 被引用回数:78 パーセンタイル:95.42(Physics, Nuclear)

Fission cross sections and fission fragment mass distributions were measured in the reactions of $$^{40}$$Ca + $$^{238}$$U and $$^{48}$$Ca + $$^{238}$$U at energies around the Coulomb barrier. Fusion probabilities were calculated based on the fluctuation dissipation model. The measured mass distributions for both reactions showed an asymmetric shape at low incident energies, whereas the distribution changed to a flat shape at higher energies. The variation of the mass distribution is explained by a change of the ratio between fusion and qasifission with nuclear orientation. The calculation reproduced the mass distributions and their energy dependence. The trajectories for fusion-fission were used to determine the fusion probability. Fusion probabilities for both reactions are identical as function of the center-of-mass energy, but they differ when plotted as function of the excitation energy. The calculated evaporation residue cross sections for the reaction $$^{48}$$Ca + $$^{238}$$U using a statistical model showed that sub-barrier fusion reaction can be applied to form the element 112.

論文

Alpha-$$gamma$$ decay studies of $$^{253}$$No and its daughter products $$^{253}$$Md, $$^{249}$$Fm

He${ss}$berger, F. P.*; Antalic, S.*; Ackermann, D.*; Kalaninov$'a$, Z.*; Heinz, S.*; Hofmann, S.*; Streicher, B.*; Kindler, B.*; Kojouharov, I.*; Kuusiniemi, P.*; et al.

European Physical Journal A, 48(5), p.75_1 - 75_9, 2012/05

 被引用回数:26 パーセンタイル:78.07(Physics, Nuclear)

Nuclear structure and decay of the isotope $$^{253}$$No and its decay products $$^{249}$$Fm and $$^{253}$$Md were investigated by means of $$alpha$$-$$gamma$$ spectroscopy. Besides the established strong $$alpha$$ transitions from the 9/2$$^{-}$$[734] Nilsson level in $$^{249}$$Fm, populated predominantly by the $$alpha$$ decay of $$^{253}$$No, into the ground-state(gs) rotational band, a couple of weaker $$alpha$$ lines were observed and placed into the $$^{249}$$Fm level scheme. The transition from the 7/2$$^{-}$$ level in $$^{249}$$Es, populated by the $$alpha$$ decay of $$^{253}$$Md, into the 9/2$$^{+}$$ member of the gs rotational band, so far established for other odd-mass Es isotopes, was observed clearly. The GEANT4 simulations were performed to investigate the influence of energy summing between $$alpha$$ particles and conversion electrons (CE) on the shape of the $$alpha$$ spectra at different implantation energies, leading to evidence for a weak $$alpha$$ decay branch of $$^{253}$$No into the gs of $$^{249}$$Fm or the ground-state rotational band, respectively.

論文

The Reaction $$^{48}$$Ca + $$^{248}$$Cm $$rightarrow$$ $$^{296}$$116$$^{*}$$ studied at the GSI-SHIP

Hofmann, S.*; Heinz, S.*; Mann, R.*; Maurer, J.*; Khuyagbaatar, J.*; Ackermann, D.*; Antalic, S.*; Barth, B.*; Block, M.*; Burkhard, H. G.*; et al.

European Physical Journal A, 48(5), p.62_1 - 62_23, 2012/05

 被引用回数:167 パーセンタイル:98.85(Physics, Nuclear)

The synthesis of element 116 in the reactions of $$^{48}$$Ca+$$^{248}$$Cm was studied at the GSI-SHIP. Four decay chains from the isotope $$^{292}$$116 and one decay $$^{293}$$116 were detected at the reaction leading to the excitation energy of 40.9 MeV. The cross sections were 3.4 and 0.9 pb, respectively. The decay character reproduced the reported data at FLNR, Russia. In the $$alpha$$ decay chain, we observed the higher $$alpha$$-particle energy in the decay of $$^{289}$$114, which suggested the population and the decay of a quasiparitcle state.

論文

Investigation of fission properties and evaporation residue measurement in the reactions using $$^{238}$$U target nucleus

西尾 勝久; 池添 博; Hofmann, S.*; Ackermann, D.*; Antalic, S.*; 有友 嘉浩; Comas, V. F.*; D$"u$llmann, Ch. E.*; Gorshkov, A.*; Graeger, R.*; et al.

EPJ Web of Conferences, 17, p.09005_1 - 09005_4, 2011/10

 被引用回数:1 パーセンタイル:47.43(Physics, Nuclear)

Fission fragment mass distributions after full momentum transfer of the projectile were measured in the reactions using a $$^{238}$$U target nucleus bombarded by $$^{30}$$Si, $$^{31}$$P, $$^{34,36}$$S, $$^{40}$$Ar, $$^{40,48}$$Ca projectiles. We observed a strong variation of the distribution as function of bombarding energy. The results were interpreted by the effects of nuclear deformation of the target nucleus on the competition between fusion and quasifission. The symmetric fission includes fusion-fission, wheres as the asymmetric fission represents quasifission. The fusion probabilities were determined with the help of fluctuation-dissipation model. The estimated evaporation residue cross sections ($$^{263,264}$$Sg and $$^{267,268}$$Hs) produced in $$^{30}$$Si + $$^{238}$$U and $$^{34}$$S+$$^{238}$$U reproduced the experimental data.

論文

Isomeric states in $$^{253}$$No and $$^{253}$$Fm

Antalic, S.*; He${ss}$berger, F. P.*; Ackermann, D.*; Heinz, S.*; Hofmann, S.*; Kalaninov$'a$, Z.*; Kindler, B.*; Khuyagbaatar, J.*; Kojouharov, I.*; Kuusiniemi, P.*; et al.

European Physical Journal A, 47(5), p.62_1 - 62_12, 2011/05

 被引用回数:29 パーセンタイル:82.87(Physics, Nuclear)

Nuclear structure and decay of isomer in $$^{253}$$No were investigated. The isotope was produced by the reaction $$^{48}$$Ca+$$^{207}$$Pb. The excitation energy of the known single-particle isomeric state (5/2$$^{+}$$[622]) was measured by delayed coincidence between $$gamma$$-rays and implanted evaporation residues and was placed into the level scheme. In addition, decay of a high-lying multi-quasiparticle isomer in $$^{253}$$No was studied using e$$^{-}$$-$$gamma$$ coincidence measurements. A rotational band populated by its de-excitation was identified in $$^{253}$$No. A new isomeric state in $$^{253}$$Fm was observed and a partial-level scheme for this isotope is suggested. In addition $$gamma$$ transitions from excited levels are reproduced for $$^{253}$$Md.

56 件中 1件目~20件目を表示