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28 results on '"Gregor, E. T."'

1. Structure of high-lying levels populated in the $^{96}$Y $\rightarrow ^{96}$Zr $\beta$ decay

Author

Mashtakov, K. R., Ponomarev, V. Yu., Scheck, M., Finch, S. W., Isaak, J., Zweidinger, M., Agar, O., Bathia, C., Beck, T., Beller, J., Bowry, M., Chapman, R., Chisthi, M. M. R., Friman-Gayer, U., Gaffney, L. P., Garrett, P. E., Gregor, E. T., Keatings, J. M., Köster, U., Löher, B., McLean, A. D., O'Donnell, D., Pai, H., Pietralla, N., Rainovski, G., Ramdhane, M., Romig, C., Rusev, G., Savran, D., Simpson, G. S., Sinclair, J., Sonnabend, K., Spagnoletti, P., Tonchev, A. P., and Tornow, W.

Subjects
Nuclear Experiment
Abstract

The nature of $J^{\pi}=1^-$ levels of $^{96}$Zr below the $\beta$-decay $Q_{\beta}$ value of $^{96}$Y has been investigated in high-resolution $\gamma$-ray spectroscopy following the $\beta$ decay as well as in a campaign of inelastic photon scattering experiments. Branching ratios extracted from $\beta$ decay allow the absolute $E1$ excitation strength to be determined for levels populated in both reactions. The combined data represents a comprehensive approach to the wavefunction of $1^-$ levels below the $Q_{\beta}$ value, which are investigated in the theoretical approach of the Quasiparticle Phonon Model. This study clarifies the nuclear structure properties associated with the enhanced population of high-lying levels in the $^{96}$Y$_{gs}$ $\beta$ decay, one of the three most important contributors to the high-energy reactor antineutrino spectrum.

Published
2020
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2. First Exploration of Neutron Shell Structure Below Lead and Beyond $\boldsymbol{N=126}$

Author

Tang, T. L., Kay, B. P., Hoffman, C. R., Schiffer, J. P., Sharp, D. K., Gaffney, L. P., Freeman, S. J., Mumpower, M. R., Arokiaraj, A., Baader, E. F., Butler, P. A., Catford, W. N., de Angelis, G., Flavigny, F., Gott, M. D., Gregor, E. T., Konki, J., Labiche, M., Lazurus, I. H., MacGregor, P. T., Martel, I., Page, R. D., Podolyák, Zs., Poleshchuk, O., Raabe, R., Recchia, F., Smith, J. F., Szwec, S. V., and Yang, J.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

The nuclei below lead but with more than 126 neutrons are crucial to an understanding of the astrophysical $r$-process in producing nuclei heavier than $A\sim190$. Despite their importance, the structure and properties of these nuclei remain experimentally untested as they are difficult to produce in nuclear reactions with stable beams. In a first exploration of the shell structure of this region, neutron excitations in $^{207}$Hg have been probed using the neutron-adding ($d$,$p$) reaction in inverse kinematics. The radioactive beam of $^{206}$Hg was delivered to the new ISOLDE Solenoidal Spectrometer at an energy above the Coulomb barrier. The spectroscopy of $^{207}$Hg marks a first step in improving our understanding of the relevant structural properties of nuclei involved in a key part of the path of the $r$-process., Comment: 6 pages, 5 figures

Published
2020
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3. Direct Evidence of Octupole Deformation in Neutron-Rich $^{144}$Ba

Author

Bucher, B., Zhu, S., Wu, C. Y., Janssens, R. V. F., Cline, D., Hayes, A. B., Albers, M., Ayangeakaa, A. D., Butler, P. A., Campbell, C. M., Carpenter, M. P., Chiara, C. J., Clark, J. A., Crawford, H. L., Cromaz, M., David, H. M., Dickerson, C., Gregor, E. T., Harker, J., Hoffman, C. R., Kay, B. P., Kondev, F. G., Korichi, A., Lauritsen, T., Macchiavelli, A. O., Pardo, R. C., Richard, A., Riley, M. A., Savard, G., Scheck, M., Seweryniak, D., Smith, M. K., Vondrasek, R., and Wiens, A.

Subjects
Nuclear Experiment
Abstract

The neutron-rich nucleus $^{144}$Ba ($t_{1/2}$=11.5 s) is expected to exhibit some of the strongest octupole correlations among nuclei with mass numbers $A$ less than 200. Until now, indirect evidence for such strong correlations has been inferred from observations such as enhanced $E1$ transitions and interleaving positive- and negative-parity levels in the ground-state band. In this experiment, the octupole strength was measured directly by sub-barrier, multi-step Coulomb excitation of a post-accelerated 650-MeV $^{144}$Ba beam on a 1.0-mg/cm$^2$ $^{208}$Pb target. The measured value of the matrix element, $\langle 3_1^- \| \mathcal{M}(E3) \| 0_1^+ \rangle=0.65(^{+17}_{-23})$ $e$b$^{3/2}$, corresponds to a reduced $B(E3)$ transition probability of 48($^{+25}_{-34}$) W.u. This result represents an unambiguous determination of the octupole collectivity, is larger than any available theoretical prediction, and is consistent with octupole deformation., Comment: 5 pages, 2 figures, 1 table, Physical Review Letters 2016

Published
2016
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4. The 46Ar(3He, d)47K direct reaction as a probe of the 46Ar proton wavefunction

Author

Brugnara, D, primary, Gottardo, A, additional, Assié, M, additional, Mengoni, D, additional, Lemasson, A, additional, Clement, E, additional, Flavigny, F, additional, Ramos, D, additional, Galtarossa, F, additional, Matta, A, additional, Girard-Alcindor, V, additional, Babo, M, additional, Bazzacco, D, additional, Beaumel, D, additional, Blumenfeld, Y, additional, Bottoni, S, additional, Datta, U, additional, de Angelis, G, additional, de France, G, additional, Dudouet, J, additional, Duenas, J, additional, Goasduff, A, additional, Gregor, E T, additional, Hammache, F, additional, Illana, A, additional, Lalanne, L, additional, Leblond, S, additional, Lombardo, I, additional, Marchini, N, additional, Million, B, additional, Recchia, F, additional, Rezynkina, K, additional, Rocchini, M, additional, Rojo, J S, additional, Siciliano, M, additional, Valiente-Dobón, J J, additional, Zanon, I, additional, and Zielinska, M, additional

Published
2023
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6. Single-particle states and parity doublets in odd- Z Ac221 and Pa225 from α -decay spectroscopy

Author

Parr, E., primary, Smith, J. F., additional, Greenlees, P. T., additional, Butler, P. A., additional, Auranen, K., additional, Chapman, R., additional, Cox, D. M., additional, Cullen, D. M., additional, Gaffney, L. P., additional, Grahn, T., additional, Gregor, E. T., additional, Grocutt, L., additional, Herzáň, A., additional, Herzberg, R.-D., additional, Hodge, D., additional, Jakobsson, U., additional, Julin, R., additional, Juutinen, S., additional, Keatings, J. M., additional, Konki, J., additional, Leino, M., additional, McKee, P. P., additional, McPeake, C., additional, Mengoni, D., additional, Mistry, A. K., additional, Singh, B. S. Nara, additional, O'Neill, G. G., additional, Pakarinen, J., additional, Papadakis, P., additional, Partanen, J., additional, Peura, P., additional, Rahkila, P., additional, Ruotsalainen, P., additional, Sandzelius, M., additional, Sarén, J., additional, Scheck, M., additional, Scholey, C., additional, Siciliano, M., additional, Smolen, M., additional, Sorri, J., additional, Spagnoletti, P., additional, Spohr, K. M., additional, Stolze, S., additional, Taylor, M. J., additional, and Uusitalo, J., additional

Published
2022
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7. Single-particle states and parity doublets in odd- Z Ac 221 and Pa 225 from α -decay spectroscopy

Author

Parr, E., Smith, J. F., Greenlees, P. T., Butler, P. A., Auranen, K., Chapman, R., Cox, D. M., Cullen, D. M., Gaffney, L. P., Grahn, T., Gregor, E. T., Grocutt, L., Herzan, A., Herzberg, R. -D., Hodge, D., Jakobsson, U., Julin, R., Juutinen, S., Keatings, J. M., Konki, J., Leino, M., Mckee, P. P., Mcpeake, C., Mengoni, D., Mistry, A. K., Singh, B. S. N., O'Neill, G. G., Pakarinen, J., Papadakis, P., Partanen, J., Peura, P., Rahkila, P., Ruotsalainen, P., Sandzelius, M., Saren, J., Scheck, M., Scholey, C., Siciliano, M., Smolen, M., Sorri, J., Spagnoletti, P., Spohr, K. M., Stolze, S., Taylor, M. J., and Uusitalo, J.

Published
2022

8. Single-particle states and parity doublets in odd-Z 221Ac and 225Pa from α-decay spectroscopy

Author

Parr, E., Smith, J. F., Greenlees, P. T., Butler, P. A., Auranen, K., Chapman, R., Cox, D. M., Cullen, D. M., Gaffney, L. P., Grahn, T., Gregor, E. T., Grocutt, L., Herzáň, A., Herzberg, R.-D., Hodge, D., Jakobsson, U., Julin, R., Juutinen, S., Keatings, J. M., Konki, J., Leino, M., McKee, P. P., McPeake, C., Mengoni, D., Mistry, A. K., Nara Singh, B. S., O'Neill, G. G., Pakarinen, J., Papadakis, P., Partanen, J., Peura, P., Rahkila, P., Ruotsalainen, P., Sandzelius, M., Sarén, J., Scheck, M., Scholey, C., Siciliano, M., Smolen, M., Sorri, J., Spagnoletti, P., Spohr, K. M., Stolze, S., Taylor, M. J., and Uusitalo, J.

Subjects
ydinfysiikka
Abstract

Low-lying states in the odd-Z isotopes 22189Ac132 and 22591Pa134 have been studied using α-particle and αγ-coincidence spectroscopy in the 225Pa→221Ac→217Fr decay chain. Ground-state spin and parity assignments of Iπ = 5/2− are proposed for both 221Ac and 225Pa, with the odd proton occupying the Ω = 5/2 orbital of the quadrupole-octupole deformed shell model in both nuclei. In 221Ac, excited states in the bands based on the Ω = 5/2 and Ω = 3/2 orbitals have been identified, including proposed parity-doublet states. The results suggest that reflection-asymmetric deformation of the ground state persists in the odd-A members of the isotope chains down to N = 132 for Ac and N = 134 for Pa, before reaching the transitional region at N = 130. peerReviewed

Published
2022

9. Structure of high-lying levels populated in the $^{96}Y$ ��� $^{96}Zr$ $��$ decay

Author

Mashtakov, K. R., Ponomarev, V. Yu., Scheck, M., Finch, S. W., Isaak, J., Zweidinger, M., Agar, O., Bathia, C., Beck, T., Beller, J., Bowry, M., Chapman, R., Chishti, M. M. R., Friman-Gayer, U., Gaffney, L. P., Garrett, P. E., Gregor, E. T., Keatings, J. M., K��ster, U., L��her, Bastian, MacLean, A. D., O'Donnell, D., Pai, H., Pietralla, N., Rainovski, G., Ramdhane, M., Romig, C., Rusev, G., Savran, D., Simpson, G. S., Sinclair, J., Sonnabend, K., Spagnoletti, P., Tonchev, A. P., and Tornow, W.

Abstract

Physics letters / B 820, 136569 (2021). doi:10.1016/j.physletb.2021.136569, Published by North-Holland Publ., Amsterdam

Published
2021
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10. Structure of high-lying levels populated in the ⁹⁶Y → ⁹⁶Zr β decay

Author

Mashtakov, K. R., Ponomarev, V. Yu., Scheck, M., Finch, S. W., Isaak, J., Zweidinger, M., Agar, O., Bathia, C., Beck, T., Beller, J., Bowry, M., Chapman, R., Chishti, M. M. R., Friman-Gayer, U., Gaffney, L. P., Garrett, P. E., Gregor, E. T., Keatings, J. M., Köster, U., Löher, B., McLean, A. D., O'Donnell, D., Pai, H., Pietralla, N., Rainovski, G., Ramdhane, M., Romig, C., Rusev, G., Savran, D., Simpson, G. S., Sinclair, J., Sonnabend, K., Spagnoletti, P., Tonchev, A. P., and Tornow, W.

Abstract

The nature of Jπ=1− levels of 96Zr below the β-decay Qβ value of 96Y has been investigated in high-resolution γ-ray spectroscopy following the β decay as well as in a campaign of inelastic photon scattering experiments. Branching ratios extracted from β decay allow the absolute E1 excitation strength to be determined for levels populated in both reactions. The combined data represents a comprehensive approach to the wavefunction of 1− levels below the Qβ value, which are investigated in the theoretical approach of the Quasiparticle Phonon Model. This study clarifies the nuclear structure properties associated with the enhanced population of high-lying levels in the 96Ygs β decay, one of the three most important contributors to the high-energy reactor antineutrino spectrum.

Published
2020

11. First Exploration of Neutron Shell Structure below Lead and beyond N=126

Author

Tang, T. L., primary, Kay, B. P., additional, Hoffman, C. R., additional, Schiffer, J. P., additional, Sharp, D. K., additional, Gaffney, L. P., additional, Freeman, S. J., additional, Mumpower, M. R., additional, Arokiaraj, A., additional, Baader, E. F., additional, Butler, P. A., additional, Catford, W. N., additional, de Angelis, G., additional, Flavigny, F., additional, Gott, M. D., additional, Gregor, E. T., additional, Konki, J., additional, Labiche, M., additional, Lazarus, I. H., additional, MacGregor, P. T., additional, Martel, I., additional, Page, R. D., additional, Podolyák, Zs., additional, Poleshchuk, O., additional, Raabe, R., additional, Recchia, F., additional, Smith, J. F., additional, Szwec, S. V., additional, and Yang, J., additional

Published
2020
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12. α-decay spectroscopy of the N = 130 isotones 218Ra and 220Th: Mitigation of α-particle energy summing with implanted nuclei

Author

Parr, E., Smith, J. F., Greenlees, P. T., Auranen, K., Butler, P. A., Chapman, R., Cox, D. M., Cullen, D. M., Gaffney, L. P., Grahn, T., Gregor, E. T., Grocutt, L., Herzán, A., Herzberg, R.-D., Hodge, D., Jakobsson, U., Julin, R., Juutinen, S., Keatings, J., Konki, J., Leino, M., McKee, P. P., McPeake, C., Mengoni, D., Mistry, A. K., Mulholland, K. F., Singh, B. S. Nara, O'Neill, G. G., Pakarinen, J., Papadakis, P., Partanen, J., Peura, P., Rahkila, P., Ruotsalainen, P., Sandzelius, M., Sarén, J., Scheck, M., Scholey, C., Siciliano, M., Smolen, M., Sorri, J., Spagnoletti, P., Spohr, K. M., Stolze, S., Taylor, M. J., and Uusitalo, J.

Subjects
nuclear data analysis and compilation, alpha decay, ydinfysiikka, spectrometers and spectroscopic techniques
Abstract

An analysis technique has been developed in order to mitigate energy summing due to sequential short-lived α decays from nuclei implanted into a silicon detector. Using this technique, α-decay spectroscopy of the N=130 isotones 218Ra (Z=88) and 220Th (Z=90) has been performed. The energies of the α particles emitted in the 218Ra→214Rn and 220Th→216Ra ground-state-to-ground-state decays have been measured to be 8381(4) keV and 8818(13) keV, respectively. The half-lives of the ground states of 218Ra and 220Th have been measured to be 25.99(10) μs and 10.4(4) μs, respectively. The half-lives of the ground states of the α-decay daughters, 214Rn and 216Ra, have been measured to be 259(3) ns and 161(11) ns, respectively. Fine structure in the α decay of 218Ra has been observed for the first time, populating the 695-keV 2+1 state in 214Rn. The fine-structure α decay has an α-particle energy of 7715(40) keV and branching ratio bα=0.123(11)%. peerReviewed

Published
2019

13. Low-lying octupole isovector excitation in Nd-144

Author

Thuerauf, M., Stoyanov, Ch, Scheck, M., Jentschel, M., Bernards, C., Blanc, A., Cooper, N., De France, G., Gregor, E. T., Henrich, C., Hicks, S. F., Jolie, J., Kaleja, O., Koster, U., Kroell, T., Leguillon, R., Mutti, P., Odonnell, D., Petrache, C. M., Simpson, G. S., Smith, J. F., Soldner, T., Tezgel, M., Urban, W., Vanhoy, J., Werner, M., Werner, V, Zell, K. O., Zerrouki, T., Thuerauf, M., Stoyanov, Ch, Scheck, M., Jentschel, M., Bernards, C., Blanc, A., Cooper, N., De France, G., Gregor, E. T., Henrich, C., Hicks, S. F., Jolie, J., Kaleja, O., Koster, U., Kroell, T., Leguillon, R., Mutti, P., Odonnell, D., Petrache, C. M., Simpson, G. S., Smith, J. F., Soldner, T., Tezgel, M., Urban, W., Vanhoy, J., Werner, M., Werner, V, Zell, K. O., and Zerrouki, T.

Abstract

The nature of low-lying 3(-) levels in Nd-144 was investigated in the Nd-143(n, gamma gamma) cold neutron-capture reaction. The combination of the high neutron flux from the research reactor at the Institut Laue-Langevin and the high gamma-ray detection efficiency of the EXILL setup allowed the recording of gamma gamma coincidences. From the coincidence data precise branching ratios were extracted. Furthermore, the octagonal symmetry of the setup allowed angular-distribution measurements to determine multipole-mixing ratios. Additionally, in a second measurement the ultra-high resolution spectrometer GAMS6 was employed to conduct lifetime measurements using the gamma-ray induced Doppler-shift technique (GRID). The confirmed strong M1 component in the 3(3)(-) -> 3(1)(-) decay strongly supports the assignment of the 3(3)(-) level at 2779 keV as low-lying isovector octupole excitation. Microscopic calculations within the quasiparticle phonon model confirm an isovector component in the wave function of the 3(3)(-) level, firmly establishing this fundamental mode of nuclear excitation in near-spherical nuclei.

Published
2019

14. Decay properties of the 3(1)(-) level in Mo-96

Author

Gregor, E. T., Arsenyev, N. N., Scheck, M., Shneidman, T. M., Thuerauf, M., Bernards, C., Blanc, A., Chapman, R., Drouet, F., Dzhioev, A. A., de France, G., Jentschel, M., Jolie, J., Keatings, J. M., Kroell, Th, Koster, U., Leguillon, R., Mashtakov, K. R., Mutti, P., O'Donnell, D., Petrache, C. M., Simpson, G. S., Sinclair, J., Smith, J. F., Soldner, T., Spagnoletti, P., Sushkov, A., V, Urban, W., Vancraeyenest, A., Vanhoy, J. R., Werner, V, Zell, K. O., Zielinska, M., Gregor, E. T., Arsenyev, N. N., Scheck, M., Shneidman, T. M., Thuerauf, M., Bernards, C., Blanc, A., Chapman, R., Drouet, F., Dzhioev, A. A., de France, G., Jentschel, M., Jolie, J., Keatings, J. M., Kroell, Th, Koster, U., Leguillon, R., Mashtakov, K. R., Mutti, P., O'Donnell, D., Petrache, C. M., Simpson, G. S., Sinclair, J., Smith, J. F., Soldner, T., Spagnoletti, P., Sushkov, A., V, Urban, W., Vancraeyenest, A., Vanhoy, J. R., Werner, V, Zell, K. O., and Zielinska, M.

Abstract

The first excited 3(1)(-) level of Mo-96 was investigated in a high-statistics experiment using the Mo-95(n, gamma gamma) cold neutron capture reaction. The measurements used the high cold neutron flux from the research reactor at Institut Laue-Langevin and employed the highly-efficient EXILL array to detect gamma-ray coincidences. The recorded statistics allow identification of decay branches with only a small relative intensity including the 3(1)(-) ( )-> 0(gs)(+) E3 decay. With the knowledge of the newly measured branching ratio and the known B (E3 , 3(1)(-) -> 0(gs)(+)) transition probability, the lifetime of the 3(1)(-) level was determined and, subsequently, the B (E1) strength of the other decay branches of the 3(1)(-) octupole phonon were calculated. The extracted electromagnetic decay strengths are compared to the systematics of the stable even-even molybdenum isotopes and values calculated in a Skyrme-force based quasi-particle random phase approximation and in a cluster approach. Additionally, the 3(1)(-) -> 2(iv)(+) decay branch to the low-lying 2(iv)(+) quadrupole isovector level was observed.

Published
2019

15. α -decay spectroscopy of the N=130 isotones Ra218 and Th220 : Mitigation of α -particle energy summing with implanted nuclei

Author

Parr, E., primary, Smith, J. F., additional, Greenlees, P. T., additional, Auranen, K., additional, Butler, P. A., additional, Chapman, R., additional, Cox, D. M., additional, Cullen, D. M., additional, Gaffney, L. P., additional, Grahn, T., additional, Gregor, E. T., additional, Grocutt, L., additional, Herzáň, A., additional, Herzberg, R.-D., additional, Hodge, D., additional, Jakobsson, U., additional, Julin, R., additional, Juutinen, S., additional, Keatings, J., additional, Konki, J., additional, Leino, M., additional, McKee, P. P., additional, McPeake, C., additional, Mengoni, D., additional, Mistry, A. K., additional, Mulholland, K. F., additional, Singh, B. S. Nara, additional, O'Neill, G. G., additional, Pakarinen, J., additional, Papadakis, P., additional, Partanen, J., additional, Peura, P., additional, Rahkila, P., additional, Ruotsalainen, P., additional, Sandzelius, M., additional, Sarén, J., additional, Scheck, M., additional, Scholey, C., additional, Siciliano, M., additional, Smolen, M., additional, Sorri, J., additional, Spagnoletti, P., additional, Spohr, K. M., additional, Stolze, S., additional, Taylor, M. J., additional, and Uusitalo, J., additional

Published
2019
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16. Decay properties of the ${3}_{1}^{-}$ level in 96Mo

Author

Gregor, E T, primary, Arsenyev, N N, additional, Scheck, M, additional, Shneidman, T M, additional, Thürauf, M, additional, Bernards, C, additional, Blanc, A, additional, Chapman, R, additional, Drouet, F, additional, Dzhioev, A A, additional, de France, G, additional, Jentschel, M, additional, Jolie, J, additional, Keatings, J M, additional, Kröll, Th, additional, Köster, U, additional, Leguillon, R, additional, Mashtakov, K R, additional, Mutti, P, additional, O’Donnell, D, additional, Petrache, C M, additional, Simpson, G S, additional, Sinclair, J, additional, Smith, J F, additional, Soldner, T, additional, Spagnoletti, P, additional, Sushkov, A V, additional, Urban, W, additional, Vancraeyenest, A, additional, Vanhoy, J R, additional, Werner, V, additional, Zell, K O, additional, and Zielińska, M, additional

Published
2019
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17. Low-lying octupole isovector excitation in Nd144

Author

Thürauf, M., primary, Stoyanov, Ch., additional, Scheck, M., additional, Jentschel, M., additional, Bernards, C., additional, Blanc, A., additional, Cooper, N., additional, De France, G., additional, Gregor, E. T., additional, Henrich, C., additional, Hicks, S. F., additional, Jolie, J., additional, Kaleja, O., additional, Köster, U., additional, Kröll, T., additional, Leguillon, R., additional, Mutti, P., additional, O'Donnell, D., additional, Petrache, C. M., additional, Simpson, G. S., additional, Smith, J. F., additional, Soldner, T., additional, Tezgel, M., additional, Urban, W., additional, Vanhoy, J., additional, Werner, M., additional, Werner, V., additional, Zell, K. O., additional, and Zerrouki, T., additional

Published
2019
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18. Decay properties of the level in 96Mo.

Author

Gregor, E T, Arsenyev, N N, Scheck, M, Shneidman, T M, Thürauf, M, Bernards, C, Blanc, A, Chapman, R, Drouet, F, Dzhioev, A A, de France, G, Jentschel, M, Jolie, J, Keatings, J M, Kröll, Th, Köster, U, Leguillon, R, Mashtakov, K R, Mutti, P, and O'Donnell, D

Subjects
*MOLYBDENUM isotopes, *NEUTRON capture, *RESEARCH reactors, *BRANCHING ratios, *NEUTRON flux, *QUASIPARTICLES
Abstract

The first excited level of 96Mo was investigated in a high-statistics experiment using the 95Mo(n, γγ) cold neutron capture reaction. The measurements used the high cold neutron flux from the research reactor at Institut Laue-Langevin and employed the highly-efficient EXILL array to detect γ-ray coincidences. The recorded statistics allow identification of decay branches with only a small relative intensity including the E3 decay. With the knowledge of the newly measured branching ratio and the known transition probability, the lifetime of the level was determined and, subsequently, the strength of the other decay branches of the octupole phonon were calculated. The extracted electromagnetic decay strengths are compared to the systematics of the stable even–even molybdenum isotopes and values calculated in a Skyrme-force based quasiparticle random phase approximation and in a cluster approach. Additionally, the decay branch to the low-lying quadrupole isovector level was observed. [ABSTRACT FROM AUTHOR]

Published
2019
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19. STUDY OF OCTUPOLE COLLECTIVITY IN Nd-146 AND Sm-148 USING THE NEW COULOMB EXCITATION SET-UP AT ALTO

Author

Komorowska, M., Zielinska, M., Napiorkowski, P., Doherty, T., Wrzosek-Lipska, K., Butler, P. A., Prochniak, L., Korten, W., Briselet, R., De Witte, H., Gaffney, L. P., Georgiev, G., Goasduff, A., Gorgen, A., Gottardo, A., Gregor, E. T., Hadynska-Klek, K., Hess, H., Klintefjord, M., Konstantinopoulos, T., Ljungvall, J., Lutter, R., Matea, I., Matuszczak, P., O'Neill, G. G., Piatek, W., Reiter, P., Rosiak, D., Scheck, M., Seidlitz, M., Siebeck, B., Thuerauf, M., Warr, N., Komorowska, M., Zielinska, M., Napiorkowski, P., Doherty, T., Wrzosek-Lipska, K., Butler, P. A., Prochniak, L., Korten, W., Briselet, R., De Witte, H., Gaffney, L. P., Georgiev, G., Goasduff, A., Gorgen, A., Gottardo, A., Gregor, E. T., Hadynska-Klek, K., Hess, H., Klintefjord, M., Konstantinopoulos, T., Ljungvall, J., Lutter, R., Matea, I., Matuszczak, P., O'Neill, G. G., Piatek, W., Reiter, P., Rosiak, D., Scheck, M., Seidlitz, M., Siebeck, B., Thuerauf, M., and Warr, N.

Abstract

For certain combinations of protons and neutrons in atomic nuclei, a rise of a reflection asymmetry is expected. Experimental E3 strengths, which as a function of the neutron number peak at around N approximate to 8 8 and N approximate to 1 3 4, indicate enhanced octupole correlations as predicted by theory. Low-energy Coulomb excitation is a highly successful method for establishing the evolution of nuclear shapes, through the measurement of cross sections, to populate excited states that can be directly related to the static and dynamic moments of the charge distribution of the nucleus. A Coulomb excitation experiment at the ALTO facility, Orsay was performed recently to study collective properties of Nd-146 and Sm-148. In particular, the strengths of the < 3(-)parallel to E3 parallel to 0(+)> and < 1(-)parallel to E3 parallel to 4(+)> matrix elements will provide a clear distinction between octupole vibration and rigid deformation.

Published
2016

20. Determination of the B(E3, 0(+) -> 3(-))-excitation strength in octupole-correlated nuclei near A approximate to 224 by the means of Coulomb excitation at REX-ISOLDE

Author

Scheck, M., Gaffney, L. P., Butler, P. A., Hayes, A. B., Wenander, F., Albers, M., Bastin, B., Bauer, C., Blazhev, A., Boenig, S., Bree, N., Cederkaell, J., Chupp, T., Cline, D., Cocolios, T. E., Davinson, T., De Witte, H., Diriken, J., Grahn, T., Gregor, E. T., Herzan, A., Huyse, M., Jenkins, D. G., Joss, D. T., Kesteloot, N., Konki, J., Kowalczyk, M., Kroell, Th., Kwan, E., Lutter, R., Moschner, K., Napiorkowski, P., Pakarinen, J., Pfeiffer, M., Radeck, D., Reiter, P., Reynders, K., Rigby, S. V., Robledo, L. M., Rudigier, M., Sambi, S., Seidlitz, M., Siebeck, B., Stora, T., Thoele, P., Van Duppen, P., Vermeulen, M. J., von Schmid, M., Voulot, D., Warr, N., Wimmer, K., Wrzosek-Lipska, K., Wu, C. Y., Zielinska, M., and Helsinki Institute of Physics

Subjects
RADIOACTIVE BEAMS, 114 Physical sciences
Abstract

Volume: 533

Published
2014

21. Investigating the Pygmy Dipole Resonance UsingβDecay

Author

Scheck, M., primary, Mishev, S., additional, Ponomarev, V. Yu., additional, Chapman, R., additional, Gaffney, L. P., additional, Gregor, E. T., additional, Pietralla, N., additional, Spagnoletti, P., additional, Savran, D., additional, and Simpson, G. S., additional

Published
2016
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22. Direct Evidence of Octupole Deformation in Neutron-RichBa144

Author

Bucher, B., primary, Zhu, S., additional, Wu, C. Y., additional, Janssens, R. V. F., additional, Cline, D., additional, Hayes, A. B., additional, Albers, M., additional, Ayangeakaa, A. D., additional, Butler, P. A., additional, Campbell, C. M., additional, Carpenter, M. P., additional, Chiara, C. J., additional, Clark, J. A., additional, Crawford, H. L., additional, Cromaz, M., additional, David, H. M., additional, Dickerson, C., additional, Gregor, E. T., additional, Harker, J., additional, Hoffman, C. R., additional, Kay, B. P., additional, Kondev, F. G., additional, Korichi, A., additional, Lauritsen, T., additional, Macchiavelli, A. O., additional, Pardo, R. C., additional, Richard, A., additional, Riley, M. A., additional, Savard, G., additional, Scheck, M., additional, Seweryniak, D., additional, Smith, M. K., additional, Vondrasek, R., additional, and Wiens, A., additional

Published
2016
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23. Determination of the B(E3, 0(+) -> 3(-))-excitation strength in octupole-correlated nuclei near A approximate to 224 by the means of Coulomb excitation at REX-ISOLDE

Author

University of Helsinki, Helsinki Institute of Physics, Scheck, M., Gaffney, L. P., Butler, P. A., Hayes, A. B., Wenander, F., Albers, M., Bastin, B., Bauer, C., Blazhev, A., Boenig, S., Bree, N., Cederkaell, J., Chupp, T., Cline, D., Cocolios, T. E., Davinson, T., De Witte, H., Diriken, J., Grahn, T., Gregor, E. T., Herzan, A., Huyse, M., Jenkins, D. G., Joss, D. T., Kesteloot, N., Konki, J., Kowalczyk, M., Kroell, Th., Kwan, E., Lutter, R., Moschner, K., Napiorkowski, P., Pakarinen, J., Pfeiffer, M., Radeck, D., Reiter, P., Reynders, K., Rigby, S. V., Robledo, L. M., Rudigier, M., Sambi, S., Seidlitz, M., Siebeck, B., Stora, T., Thoele, P., Van Duppen, P., Vermeulen, M. J., von Schmid, M., Voulot, D., Warr, N., Wimmer, K., Wrzosek-Lipska, K., Wu, C. Y., Zielinska, M., University of Helsinki, Helsinki Institute of Physics, Scheck, M., Gaffney, L. P., Butler, P. A., Hayes, A. B., Wenander, F., Albers, M., Bastin, B., Bauer, C., Blazhev, A., Boenig, S., Bree, N., Cederkaell, J., Chupp, T., Cline, D., Cocolios, T. E., Davinson, T., De Witte, H., Diriken, J., Grahn, T., Gregor, E. T., Herzan, A., Huyse, M., Jenkins, D. G., Joss, D. T., Kesteloot, N., Konki, J., Kowalczyk, M., Kroell, Th., Kwan, E., Lutter, R., Moschner, K., Napiorkowski, P., Pakarinen, J., Pfeiffer, M., Radeck, D., Reiter, P., Reynders, K., Rigby, S. V., Robledo, L. M., Rudigier, M., Sambi, S., Seidlitz, M., Siebeck, B., Stora, T., Thoele, P., Van Duppen, P., Vermeulen, M. J., von Schmid, M., Voulot, D., Warr, N., Wimmer, K., Wrzosek-Lipska, K., Wu, C. Y., and Zielinska, M.

Published
2014

24. β DECAY AS A NEW PROBE FOR THE LOW-ENERGY E1 STRENGTH.

Author

SCHECK, M., MISHEV, S., PONOMAREV, V. YU., AGAR, O., BECK, T., BLANC, A., CHAPMAN, R., GAYER, U., GAFFNEY, L. P., GREGOR, E. T., KEATINGS, J., KOSEOGLOU, P., KÖSTER, U., MASHTAKOV, K. R., O'DONNELL, D., PAI, H., PIETRALLA, N., SAVRAN, D., SMITH, J. F., and SPAGNOLETTI, P.

Subjects
GROUND state (Quantum mechanics), RADIOACTIVE decay, WAVE functions, MICROSCOPY, QUASIPARTICLE-phonon model
Abstract

In this contribution, it is evaluated whether high Q-value β decays from mothers with low ground-state spin are suitable to probe the structure of 1-levels associated with the pygmy dipole response. A comparison of data from the exemplary 136I →136Xe β decay and the 136Xe(γ,γ) reaction reveals that some 1- levels are populated in both reactions but with a different pattern. An investigation within the microscopic quasiparticle phonon model shows that the pattern is related to the population of different parts of the wave functions of these 1- levels establishing β decay as a novel probe. [ABSTRACT FROM AUTHOR]

Published
2017
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25. Determination of theB(E3, 0+→ 3−)-excitation strength in octupole-correlated nuclei nearA≈ 224 by the means of Coulomb excitation at REX-ISOLDE

Author

Scheck, M, primary, Gaffney, L P, additional, Butler, P A, additional, Hayes, A B, additional, Wenander, F, additional, Albers, M, additional, Bastin, B, additional, Bauer, C, additional, Blazhev, A, additional, Bönig, S, additional, Bree, N, additional, Cederkäil, J, additional, Chupp, T, additional, Cline, D, additional, Cocolios, T E, additional, Davinson, T, additional, Witte, H De, additional, Diriken, J, additional, Grahn, T, additional, Gregor, E T, additional, Herzan, A, additional, Huyse, M, additional, Jenkins, D G, additional, Joss, D T, additional, Kesteloot, N, additional, Konki, J, additional, Kowalczyk, M, additional, Kröll, Th, additional, Kwan, E, additional, Lutter, R, additional, Moschner, K, additional, Napiorkowski, P, additional, Pakarinen, J, additional, Pfeiffer, M, additional, Radeck, D, additional, Reiter, P, additional, Reynders, K, additional, Rigby, S V, additional, Robledo, L M, additional, Rudigier, M, additional, Sambi, S, additional, Seidlitz, M, additional, Siebeck, B, additional, Stora, T, additional, Thoele, P, additional, Duppen, P Van, additional, Vermeulen, M J, additional, Schmid, M von, additional, Voulot, D, additional, Warr, N, additional, Wimmer, K, additional, Wrzosek-Lipska, K, additional, Wu, C Y, additional, and Zielińska, M, additional

Published
2014
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26. STUDY OF OCTUPOLE COLLECTIVITY IN 146Nd AND 148Sm USING THE NEW COULOMB EXCITATION SET-UP AT ALTO.

Author

KOMOROWSKA, M., ZIELIŃSKA, M., NAPIORKOWSKI, P., DOHERTY, D. T., WRZOSEK-LIPSKA, K., BUTLER, P. A., PRÓCHNIAK, L., KORTEN, W., BRISELET, R., DE WITTE, H., GAFFNEY, L. P., GEORGIEV, G., GOASDUFF, A., GÖRGEN, A., GOTTARDO, A., GREGOR, E. T., HADYNSKA-KLEK, K., HESS, H., KLINTEFJORD, M., and KONSTANTINOPOULOS, T.

Subjects
COULOMB excitation, ATOMIC nucleus, GRAVITY assist (Astrodynamics), VIBRATION (Mechanics), NUCLEAR excitation
Abstract

For certain combinations of protons and neutrons in atomic nuclei, a rise of a reflection asymmetry is expected. Experimental E3 strengths, which as a function of the neutron number peak at around N ≈ 88 and N ≈ 134, indicate enhanced octupole correlations as predicted by theory. Low-energy Coulomb excitation is a highly successful method for establishing the evolution of nuclear shapes, through the measurement of cross sections, to populate excited states that can be directly related to the static and dynamic moments of the charge distribution of the nucleus. A Coulomb excitation experiment at the ALTO facility, Orsay was performed recently to study collective properties of 146Nd and 148Sm. In particular, the strengths of the <3-∣∣E3∣∣0+> and <1-∣∣E3∣∣4+> matrix elements will provide a clear distinction between octupole vibration and rigid deformation. [ABSTRACT FROM AUTHOR]

Published
2016
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27. DEVELOPMENT OF SLOWED DOWN BEAMS AT THE FRAGMENT SEPARATOR FOR FAIR.

Author

Naqvi, F., Boutachkov, P., Górska, M., Gerl, J., Farinon, F., Gregor, E. T., Hadynska, K., Jhingan, A., Janik, R., Kojouharov, I., Kondratyev, N. A., Alvarez, M. A. G., Mukha, I., Napiorkowski, P., Nociforo, C., Pietak, D., Prokopowicz, W., Pietri, S., Prochazka, A., and Schaffner, H.

Subjects
PARTICLE beams, NUCLEAR fragmentation, FEASIBILITY studies, NICKEL isotopes, ALUMINUM, NUCLEAR energy, SIMULATION methods & models
Abstract

The feasibility studies of the slowed down beam setup involving deceleration of a 64Ni beam at 250 MeV/u to 13 MeV/u in a thick Al degrader was performed at the FRagment Separator (FRS) at GSI. The experimentally measured energy spread and the nuclear reaction yields in the degrader are in good agreement with simulations. [ABSTRACT FROM AUTHOR]

Published
2011
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