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35 results on '"Grahn T."'

1. Identification of excited states in 107,52Te55

Author

Zhang, W., Cederwall, B., Qi, C., Ertoprak, A., Aktas, Ö., Liu, X., Andgren, K., Auranen, K., Bäck, T., Barber, L., Beeton, G., Cullen, D. M., Darby, I. G., Dimmock, M. R., Eeckhaudt, S., Ganioğlu, E., Górska, M., Grahn, T., Greenlees, P. T., Hadinia, B., Ideguchi, E., Illana, A., Jones, P. M., Joss, D. T., Julin, R., Juutinen, S., Keatings, J. M., Khaplanov, A., Kulali, F., Leino, M., Luoma, M., Lv, B., Nara Singh, B. S., Nelson, L., Niikura, M., Nyman, M., Ojala, J., Page, R. D., Pakarinen, J., Paul, E. S., Petrache, C., Petri, M., Rahkila, P., Ruotsalainen, P., Sandzelius, M., Sarén, J., Scholey, C., Smith, J. F., Sorri, J., Tann, H., Zimba, G., Uusitalo, J., Wadsworth, R., and Wyss, R.

Subjects
isotoopit, telluuri, nuclear physics, nuclear structure, ydinfysiikka
Abstract

Excited states in the extremely neutron-deficient nucleus 107Te have been identified from two separate experiments using the recoil-decay tagging technique. Two connected structures were observed on the basis of γγ-coincidence relations and tentatively assigned as built on the mixed-parentage νg7/2d5/2 and νh11/2 intruder configurations. The observed structures were compared with large-scale shell-model calculations and total Routhian surface calculations. Collective behavior was discovered to persist in the νh11/2 band of 107Te which highlights the shape-polarizing effect of a single valence neutron occupying the h11/2 intruder orbit as the N=50 shell closure is approached. peerReviewed

Published
2021

2. Precision measurements of proton emission from the ground states of 156Ta and 160Re

Author

Darby, I. G., Page, R. D., Joss, D. T., Bianco, L., Grahn, T., Judson, D. S., Simpson, J., Eeckhaudt, S., Greenlees, P. T., Jones, P. M., Julin, R., Juutinen, S., Ketelhut, S., Leino, M., Leppänen, A.-P., Nyman, M., Rahkila, P., Sarén, J., Scholey, C., Steer, A. N., Uusitalo, J., Venhart, M., Ertürk, S., Gall, B., and Hadinia, B.

Subjects
nuclear physics, ydinfysiikka
Abstract

The decays of the πd3/2 ground states of 156Ta and 160Re have been studied in detail using the GREAT spectrometer. More than 7000 160Re nuclei were produced in reactions of 290- and 300-MeV 58Ni ions with an isotopically enriched 106Cd target and separated in flight using the RITU separator. The proton and α decays of the πd3/2 level were confirmed and the half-life and branching ratios of this state were determined with improved precision to be t1/2=611±7 μs and bp=89±1% and bα=11±1%, respectively. The α-decay branch populated the ground state of 156Ta, allowing improved values for the proton-decay energy and half-life to be obtained (Ep=1011±5 keV; t1/2=106±4 ms). The β decay of this level was identified for the first time and a branching ratio of bβ=29±3% was deduced. The spectroscopic factors deduced from these measurements are compared with predictions. peerReviewed

Published
2011

3. EXPERIMENTS AT THE FRONTIERS OF NUCLEAR PHYSICS: THE EXPERIMENTAL PROGRAM OF THE SUPER-FRS COLLABORATION.

Author

Scheidenberger, C., Äystö3, J., Behr, K.-H., Benlliure, J., Bracco, A., Egelhof, P., Fomichev, A., Galès, S., Geissel, H., Grahn, T., Grigorenko, L., Harakeh, M. N., Hayano, R., Heinz, S., Itahashi, K., Jokinen, A., Kalantar-Nayestanaki, N., Kanungo, R., Lenske, H., and Muenzenberg, G.

Subjects
NUCLEAR physics, EXOTIC nuclei, HIGH resolution spectroscopy, ISOTOPES, ATOMIC collisions, HYPERFRAGMENTS
Published
2015

4. A NEW PLUNGER DEVICE FOR INVESTIGATING THE EFFECTS OF DEFORMATION ON PROTON EMISSION RATES VIA LIFETIME MEASUREMENTS.

Author

TAYLOR, M. J., CULLEN, D. M., SMITH, A. J., MCFARLANE, A., TWIST, V., PROCTER, M. G., ALHARSHAN, G. A., BRAUNROTH, T., DEWALD, A., ELLINGER, E., FRANSEN, C., BUTLER, P. A., SCHECK, M., JOSS, D. T., SAYGI, B., MCPEAKE, C. G., GRAHN, T., GREENLEES, P. T., JAKOBSSON, U., and JONES, P.

Subjects
PROTON emission decay, EXOTIC nuclei, DECAY schemes (Radioactivity), NUCLEAR physics, PARTICLES (Nuclear physics)
Published
2013

5. EVOLUTION OF NUCLEAR STRUCTURE IN NEUTRON-DEFICIENT PB ISOTOPES.

Author

PAKARINEN, J., WADSWORTH, R., ANDREYEV, A., EECKHAUDT, S., GRAHN, T., GREENLEES, P. T., JENKINS, D. G., JONES, P., JOSHI, P., JULIN, R., JUUTINEN, S., KETTUNEN, H., LEINO, M., LEPPÄNEN, A. P., NIEMINEN, P., PAGE, R. D., PERKOWSKI, J., RADDON, P., RAHKILA, P., and SCHOLEY, C.

Subjects
NUCLEAR structure, NEUTRONS, ISOTOPES, ATOMIC nucleus, ATOMIC structure, NUCLEAR physics
Published
2013

6. Lifetime measurement in the proton-unbound nucleus 109I.

Author

Procter, M. G., Cullen, D. M., Ruotsalainen, P., Scholey, C., Angus, L., Bäck, T., Cederwall, B., Dewald, A., Fransen, C., Grahn, T., Greenlees, P. T., Hackstein, M., Jakobsson, U., Jones, P. M., Julin, R., Juutinen, S., Ketelhut, S., Leino, M., Lumley, N. M., and Mason, P. J. R.

Subjects
IODINE isotopes, PROTON decay, DOPPLER effect, NUCLEAR shell theory, PARTICLES (Nuclear physics), NUCLEAR physics
Abstract

The Recoil-Distance Doppler-shift method has been combined with Recoil-Decay Tagging for the first time to measure a lifetime in the proton-unbound nucleus 109I. The lifetime value was determined using the Differential Decay-Curve method in singles mode. The result has been compared to theoretical shell-model calculations in order to better understand the nature of unbound valence nucleons at the proton drip line. [ABSTRACT FROM AUTHOR]

Published
2011
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7. Investigation of 246Fm : in-beam spectroscopy at the limits.

Author

Piot, J., Dorvaux, O., Gall, B. J.-P., Greenlees, P. T., Andersson, L. L., Cox, D. M., Dechery, F., Grahn, T., Hauschild, K., Henning, G., Herzan, A., Herzberg, R.-D., Heßberger, F. P., Jakobsson, U., Jones, P., Julin, R., Juutinen, S., Ketelhut, S., Khoo, T.-L., and Leino, M.

Subjects
IN-beam gamma ray spectroscopy, NUCLEAR structure, PHYSICS experiments, PARTICLES (Nuclear physics), SCIENTIFIC observation, NUCLEAR physics, GAMMA ray spectrometry
Abstract

The structure of 246Fm has been investigated using in-beam γ-ray spectroscopy. The experiment was performed at the University of Jyväskylä using JUROGAM 2 coupled to RITU and GREAT. The 246Fm nuclei were produced using a 186 MeV beam of 40Ar impinging on a target of 208Pb. JUROGAM 2 was fully instrumented with TNT2D digital acquisition cards. The use of digital acquisition cards and a rotating target allowed for unprecedented beam intensities up to 71 particle-nanoamperes for prompt γ-ray spectroscopy. With all these major advances for spectroscopy a rotational band is observed for the first time in 246Fm and discussed here. [ABSTRACT FROM AUTHOR]

Published
2011
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8. Probing collectivity in the vicinity of neutron deficient Pb nuclei.

Author

Grahn, T., Dewald, A., Hornillos, M. B. Gómez, Greenlees, P. T., Görgen, A., Helariutta, K., Jolie, J., Jones, P., Julin, R., Juutinen, S., Ketelhut, S., Krücken, R., Kröll, T., Leino, M., Ljungvall, J., Maierbeck, P., Melon, B., Nyman, M., Page, R. D., and Petts, A.

Subjects
*PARTICLES (Nuclear physics), *NUCLEAR physics, *NEUTRONS, *ATOMS, *BARYONS
Abstract

A series of recoil distance Doppler-shift lifetime measurements have been carried out to probe collectivity and configuration mixing of different shapes in the vicinity of neutron mid-shell Pb nuclei. Lifetime measurements of 186Pb and 194Po, the first ever utilizing the recoil-decay tagging method, probed the collectivity of coexisting prolate and oblate shapes in this region. Futher lifetime measurements of excited states in 180Hg, 182Hg and 196Po have been carried out. [ABSTRACT FROM AUTHOR]

Published
2008
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9. Isomer Tagging with a Dual Multi-Wire Proportional Counter & a Differential Plunger.

Author

Cullen, D. M., Mason, P. J. R., Rigby, S. V., Khan, S., Kishada, A. M., Varley, B. J., Scholey, C., Grahn, T., Greenlees, P., Rahkila, P., Jones, P. M., Julin, R., Juutinen, S., Leino, M., Leppänen, A. P., Nieminen, P., Nyman, M., Pakarinen, J., and Uusitalo, J.

Subjects
NUCLEAR isomers, NUCLEAR counters, PARTICLES (Nuclear physics), NUCLEAR physics
Abstract

This report details the status of an experimental research programme which has studied isomeric states in the mass 130–160 region of the nuclear chart. Several new isomers have been established and characterised near the proton drip line using a recoil isomer tagging technique at the University of Jyväskylä, Finland. The latest experiments have been performed with a modified setup where the standard GREAT focal-plane double-sided silicon-strip detector was changed to a dual multi-wire proportional-counter arrangement. This new setup has improved capability for short-lived isomer studies where large focal-plane rates can be tolerated. The results of key recent experiments for nuclei situated above (153Yb, 152Tm) and below (144Ho, 142Tb) the N = 82 shell gap were presented. These studies have charted the evolution of isomeric states across the neutron shell from K-Isomers at N = 74, to shape isomers at N = 77 and shell-model isomers at N = 82, 83. The excitation energies for some of the lowest-lying excited states in these isomeric nuclei show behaviour which is characteristic of an X(5) symmetry falling midway between the limits expected for pure vibrational and rotational behaviour. The future prospects for studies of these nuclei were discussed using an isomer-tagged differential-plunger setup. This technique will be capable of establishing the deformation of the states above the isomers and will aid in determining whether their behaviour is indeed well described by the X(5) symmetry limit. [ABSTRACT FROM AUTHOR]

Published
2008
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10. Spectroscopy of Very Heavy Elements.

Author

Greenlees, P. T., Herzberg, R.-D., Ketelhut, S., Ackermann, D., Butler, P. A., Chatillon, A., Eeckhaudt, S., Gall, B. J. P., Grahn, T., Gray-Jones, C., Görgen, A., Heßberger, F.-P., Jakobsson, U., Jones, G. D., Jones, P., Julin, R., Juutinen, S., Khoo, T.-L., Korten, W., and Leino, M.

Subjects
SPECTRUM analysis, CHEMICAL elements, MOMENTS of inertia, NUCLEAR physics, HEAVY nuclei
Abstract

Advances in spectroscopic techniques have meant that heavy nuclei in the upper right-hand corner of the nuclear chart have become amenable to detailed study. This detailed spectroscopic data can provide a stringent test for current nuclear structure theories. Experiments to investigate the structure of nuclei in the region of 254No can yield information concerning moments of inertia, stability against fission with rotation, single-particle properties, excitation energies of two quasi-particle states, and so on. A brief overview of the techniques used and recent results from studies in the region of 254No are presented, along with a summary of future developments which will allow further advances to be made. [ABSTRACT FROM AUTHOR]

Published
2008
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11. Discovery of the proton emitting nucleus 159Re.

Author

Joss, D. T., Darby, I. G., Page, R. D., Uusitalo, J., Eeckhaudt, S., Grahn, T., Greenlees, P. T., Jones, P. M., Julin, R., Juutinen, S., Ketelhut, S., Leino, M., Leppänen, A.-P., Nyman, M., Pakarinen, J., Rahkila, P., Sarén, J., Scholey, C., Steer, A. N., and Al-Khalili, J. S.

Subjects
NUCLEAR physics, NUCLEAR reactions, RADIOACTIVITY, PROTONS, SPECTRUM analysis instruments, SPECTROMETERS
Abstract

The observation of the new nuclide 159Re provides important insights into the evolution of single-particle structure in heavy nuclei beyond the proton drip line. The nuclide 159Re was synthesised in the reaction 106Cd(58Ni,p4n) and identified via its proton radioactivity using the RITU gas-filled separator and the GREAT focal-plane spectrometer. Comparisons of the measured proton energy (Ep = 1805±20 keV) and decay half-life (t1/2 = 21±4 μs) with values calculated using the WKB method indicate that the proton is emitted from an h11/2 state. The implications of these results for future experimental investigations into even more proton unbound Re isotopes using in-flight separation techniques are considered. [ABSTRACT FROM AUTHOR]

Published
2007
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12. Advances Toward and Beyond the Proton Drip line with Recoil-Isomer Tagging.

Author

Cullen, D. M., Rigby, S. V., Scholes, D. T., Scholey, C., Rahkila, P., Eeckhaudt, S., Grahn, T., Greenlees, P., Jones, P. M., Julin, R., Juutinen, S., Kettunen, H., Leino, M., Leppänen, A., Nieminen, P., Nyman, M., Pakarinen, J., and Uusitalo, J.

Subjects
NUCLEAR isomers, NUCLEAR physics, PHYSICS, PROTONS, GADOLINIUM
Abstract

This paper reviews the past, present and future status of recoil-isomer tagging at the University of Jyväskylä. The main focus of this research has been to access isomeric states at and beyond the mass ≈140 proton drip line. Recoil-isomer tagging was first used at the University of Jyväskylä in 1998 to establish the prompt rotational band built upon a Kπ = 8- isomeric state in 138Gd. Since that time a series of experiments have been performed which have studied isomeric states in the N = 77 isotones 63140Eu77, 65142Tb77 and 67144Ho77, and in the N = 74 K-isomer chain, 64138Gd74 and 66140Dy74. These experiments have revealed valuable first information about deformations, single-particle excitation energies and hindrance factors in nuclei at and beyond the proton drip line where little or no information previously existed. The results of the most-recent experiments were discussed. These experiments established new isomeric states in 66143Dy77, 61136Pm75, and 64137Gd73 and a further two isomers which are currently unplaced. The paper concludes with a discussion of the future prospects for this research including the increased efficiency of the recoil-isomer tagging technique with a new Multi-Wire Proportional Counter (MWPC) detector which was designed and built at the University of Manchester. The first results from this new setup were shown. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2006
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13. Heavy Element Spectroscopy At JYFL.

Author

Greenlees, P. T., Amzal, N., Bastin, J. E., Bouchez, E., Butler, P. A., Chatillon, A., Dorvaux, O., Eeckhaudt, S., Eskola, K., Gall, B., Gerl, J., Grahn, T., Görgen, A., Hammond, N. J., Hauschild, K., Herzberg, R.-D., Heßberger, F.-P., Humphreys, R. D., Hürstel, A., and Jenkins, D. G.

Subjects
HEAVY elements, GAMMA ray measurement, SILICON, GERMANIUM, SPECTRUM analysis, NUCLEAR structure, NUCLEAR physics
Abstract

A series of experiments to study the properties of transfermium nuclei have been performed at the Department of Physics of the University of Jyväskylä. The experiments are carried out by a large group of collaborating institutes. These studies have been rendered possible by the coupling of various state-of-the-art detector systems to the RITU gas-filled recoil separator. In-beam conversion-electron and gamma-ray measurements have been made using the SACRED silicon and JuroGam germanium-detector arrays, respectively. The introduction of the GREAT spectrometer and TDR data acquisition system have greatly improved the quality of the data obtained at RITU. A brief overview of the instrumentation used and highlights from recent experiments are presented. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2005
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14. Proton decay studies at the gas-filled separator RITU.

Author

Kettunen, H., Eeckhaudt, S., Engvist, T., Grahn, T., Greenlees, P.T., Jones, P., Julin, R., Juutinen, S., Keenan, A., Kuusiniemi, P., Leino, M., Leppänen, A.-P., Nieminen, P., Pakarinen, J., Rahkila, P., Scholey, C., and Uustalo, J.

Subjects
NUCLEAR physics, NEUTRONS, MACHINE separators, ISOTOPES, ALPHA decay
Abstract

The gas-filled recoil separator ritu has been used to study neutron-deficient nuclei above the N=82 neutron shell closure and beyond the proton drip line. New information about the proton emitting nuclei in Ir, Au and Tl isotopes was obtained including the identification of two new proton emitters. The systematics of low-lying states in odd-mass At isotopes beyond the proton drip line were studied down to 191At using alpha-decay. A new low-lying state associated with an oblate π(2p - 1h) configuration was also observed in the corresponding Bi daughter nuclei. In order to realise these studies at the extreme limit of experimental devices, several technical developments at the ritu separator were required. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2003
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15. Structure of rotational bands in 253No.

Author

Herzberg, R.-D., Moon, S., Eeckhaudt, S., Greenlees, P. T., Butler, P. A., Page, T., Afanasjev, A. V., Amzal, N., Bastin, J. E., Becker, F., Bender, M., Bruyneel, B., Cocks, J. F. C., Darby, I. G., Dorvaux, O., Eskola, K., Gerl, J., Grahn, T., Gray-Jones, C., and Hammond, N. J.

Subjects
LASER beams, ELECTRON spectroscopy, EXOTIC nuclei, PARTICLES (Nuclear physics), NUCLEAR physics
Abstract

In-beam gamma-ray and conversion electron spectroscopic studies have been performed on the 253 No nucleus. A strongly coupled rotational band has been identified and the improved statistics allows an assignment of the band structure as built on the $\ensuremath 9/2^-[734]_{\nu}$ ground state. The results agree with previously known transition energies but disagree with the tentative structural assignments made in earlier work. [ABSTRACT FROM AUTHOR]

Published
2009
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16. Lifetime measurement in 195Po.

Author

Grahn, T., Dewald, A., Greenlees, P., Jakobsson, U., Jolie, J., Jones, P., Julin, R., Juutinen, S., Ketelhut, S., Kröll, T., Krücken, R., Leino, M., Maierbeck, P., Melon, B., Nyman, M., Page, R., Peura, P., Pissulla, Th., Rahkila, P., and Sarén, J.

Subjects
*NUCLEAR physics, *PARTICLES (Nuclear physics), *DOPPLER effect, *SPECTRUM analysis, *NEUTRON beams, *FINITE nuclei
Abstract

The lifetime of the 17/2+ yrast state in 195Po has been measured using the recoil distance Doppler-shift technique to be $ \tau$ = 43(11) ps. The lifetime was extracted from the singles $ \gamma$ -ray spectra obtained by using the recoil-decay tagging method. The present work provides more information of the coupling schemes, shapes and configuration mixing in neutron-deficient odd-mass Po nuclei. [ABSTRACT FROM AUTHOR]

Published
2009
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17. THE NORTHWEST FRONTIER: SPECTROSCOPY OF N ∼ Z NUCLEI BELOW MASS 100.

Author

WADSWORTH, R., SINGH, B. S. NARA, STEER, A. N., JENKINS, D. G., BENTLEY, M. A., BROCK, T., DAVIES, P., GLOVER, R., PATTABIRAMAN, N. S., SCHOLEY, C., GRAHN, T., GREENLEES, P. T., JONES, P., JAKOBSSON, U., JULIN, R., JUUTINEN, S., KETELHUT, S., LEINO, M., NYMAN, M., and PERUA, P.

Subjects
NUCLEAR spectroscopy, NUCLEAR physics, NUCLEAR fusion, NUCLEAR fragmentation, NUCLEAR isomers
Abstract

The spectroscopy and structure of excited states of N ~ Z nuclei in the mass 70-100 region has been investigated using two techniques. In the A ~ 70-80 region fusion evaporation reactions coupled with the recoil- β-tagging method have been employed at Jyvaskyla to study low-lying states in odd-odd N = Z nuclei. Results from these and other data for known odd-odd nuclei above mass 60 will be discussed. In the heavier mass 90 region a fragmentation experiment has been performed using the RISING/ FRS setup at GSI. This experiment was primarily aimed at searching for spin gap isomers in nuclei around A ~ 96. The objectives of the latter experiment will be discussed. [ABSTRACT FROM AUTHOR]

Published
2009

18. Lifetimes of intruder states in 186Pb, 188Pb and 194Po.

Author

Grahn, T., Dewald, A., Möller, O., Julin, R., Beausang, C. W., Christen, S., Darby, I. G., Eeckhaudt, S., Greenlees, P. T., Görgen, A., Helariutta, K., Jolie, J., Jones, P., Juutinen, S., Kettunen, H., Kröll, T., Krücken, R., Coz, Y. Le, Leino, M., and Leppänen, A.-P.

Subjects
*PARTICLES (Nuclear physics), *NUCLEAR physics, *INTERNATIONAL relations, *DOPPLER effect
Abstract

Lifetimes of prolate intruder states in 186Pb and 188Pb and oblate intruder states in 194Po have been determined through recoil distance Doppler-shift lifetime measurements. Deformation parameters of |β2| = 0.29(5) and |β2| = 0.17(3) have been extracted from experimental B(E2) values for the prolate and the oblate bands, respectively. The present study addresses the phenomenon of shape coexistence typical for the nuclei near Z = 82 and N = 104, providing information on configuration mixing of intrinsic structures of the nuclei of interest. The results are compared with the available lifetime data and theoretical results for neutron-deficient Po, Pb, Hg and Pt nuclei. Furthermore, new self-consistent mean-field calculations have been carried out for 194Po. [Copyright &y& Elsevier]

Published
2008
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19. Recoil-fission tagging of the transfermium nucleus 252No.

Author

Leppänen, A., Uusitalo, J., Greenlees, P., Herzberg, R., Amzal, N., Becker, F., Butler, P., Chewter, A., Cocks, J., Dorvaux, O., Eeckhaudt, S., Eskola, K., Gerl, J., Grahn, T., Hammond, N., Hauschild, K., Helariutta, K., Heßberger, F., Houry, M., and Jones, G.

Subjects
NUCLEAR fission, BEAM dynamics, GERMANIUM, RADIOACTIVE decay, SPECTRUM analysis, NUCLEAR physics
Abstract

An in-beam study of the transfermium nucleus 252No has been performed using the JUROSPHERE II array of germanium detectors coupled to the gas-filled recoil separator RITU. A new technique of recoil-fission tagging was used to extract tagged γ-ray data. Having significant spontaneous fission and α-decay branches, 252No is an ideal candidate for a comparative study. In a similar manner to α-decay tagging the fission events can be used to obtain γ-ray data. The recoil-fission tagged γ-ray spectrum showed a similar structure to the α-decay tagged γ-ray spectrum. By comparing the α-tagged and fission-tagged spectra and decay curves, it was shown that the spontaneous fission originates from the same initial state as the α decay. This extension of the tagging method allows in-beam spectroscopic data to be obtained from heavy nuclei with significant spontaneous-fission branches. [ABSTRACT FROM AUTHOR]

Published
2006
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20. In-beam and decay spectroscopy of transfermium elements.

Author

Greenlees, P. T., Amzal, N., Bastin, J. E., Bouchez, E., Butler, P. A., Chatillon, A., Dorvaux, O., Eeckhaudt, S., Eskola, K., Gall, B., Gerl, J., Grahn, T., Görgen, A., Hammond, N. J., Hauschild, K., Herzberg, R.-D., Heßberger, F.-P., Humphreys, R. D., Hürstel, A., and Jenkins, D. G.

Subjects
EXOTIC nuclei, BETA decay, SPECTROMETERS, NUCLEAR physics, PHYSICS
Abstract

Over the past few years a great deal of new spectroscopic data has been obtained for transfermium nuclei. Recoil separators, coupled with modern target position and focal-plane spectrometers, allow detailed studies of the structure and decay properties of transfermium nuclei to be peformed. In-beam studies using the recoil-gating and recoil-decay tagging techniques mainly provide information on yrast states, whilst complementary focal-plane decay studies give access to non-yrast and isomeric structures. In-beam studies of nuclei in this region have largely been performed at ANL and JYFL, and decay experiments at GSI, JYFL, GANIL and ANL. The present contribution is focussed on recent developments and experiments carried out by a number of collaborating institutes at JYFL. [ABSTRACT FROM AUTHOR]

Published
2005
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21. In-beam spectroscopy of 254No.

Author

Eeckhaudt, S., Amzal, N., Bastin, J. E., Bouchez, E., Butler, P. A., Chatillon, A., Eskola, K., Gerl, J., Grahn, T., Greenlees, P. T., Görgen, A., Herzberg, R.-D., Hessberger, F. P., Hürstel, A., Ikin, P. J. C., Jones, G. D., Jones, P., Julin, R., Juutinen, S., and Kettunen, H.

Subjects
IN-beam gamma ray spectroscopy, GAMMA ray spectrometry, SPECTRUM analysis, PARTICLES (Nuclear physics), PHYSICS, NUCLEAR physics
Abstract

Evidence for the presence of non-yrast states in 254No has been observed in two different in-beam experiments carried out at the University of Jyväskylä. Firstly an in-beam conversion electron spectroscopic study was performed with the SACRED spectrometer, revealing a distribution consisting of high-multiplicity electron cascades. This provides an indirect proof of the presence of high K-bands in 254No. In a more recent in-beam γ-ray spectroscopic measurement, evidence for the decay of non-yrast states in 254No has been observed for the first time. It is speculated that the observation of high-energy γ rays is due to the decay of a K = 3 band-head state. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2006
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22. Probe of Triple Shape Coexistence In Neutron Deficient Polonium Nuclei.

Author

Wiseman, D. R., Andreyev, A. N., Page, R. D., Darby, I. G., Eeckhaudt, S., Grahn, T., Greenlees, P. T., Jones, P., Julin, R., Juutinen, S., Kettunen, H., Leino, M., Leppänen, A.-P., Nyman, M., Pakarinen, J., Rahkila, P., Sandzelius, M., Sarén, J., Scholey, C., and Uusitalo, J.

Subjects
POLONIUM, RADIOACTIVE substances, NEUTRONS, NUCLEAR physics, PHYSICS, PARTICLES (Nuclear physics)
Abstract

γ-ray transitions in the neutron deficient 190,197Po nuclei have been identified. The yrast band of 190Po has been extended up to a spin and parity of 14+ and is found to display similar systematic behaviour to isotones 186Hg and 188Pb above the 4+ level, thus confirming its prolate nature. In 197Po the band built upon the 13/2+ isomer has been extended up to a spin and parity of 33/2+, while the non-yrast side-band has been observed for the first time. The behaviour of 197Po is found to be similar to that of the nearby even-mass isotopes, which is consistent with the model in which the i13/2 neutron is weakly coupled to the states in the even-even core. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2006
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23. In-beam gamma-ray spectroscopy of 254No.

Author

Eeckhaudt, S., Amzal, N., Bastin, J. E., Bouchez, E., Butler, P. A., Chatillon, A., Eskola, K., Gerl, J., Grahn, T., Görgen, A., Greenlees, P. T., Herzberg, R.-D., Hessberger, F. P., Hürstel, A., Ikin, P. J. C., Jones, G. D., Jones, P., Julin, R., Juutinen, S., and Kettunen, H.

Subjects
GERMANIUM, DETECTORS, SPECTRUM analysis, NUCLEAR physics, PHYSICS
Abstract

The recoil-tagging technique has been employed to perform an in-beam gamma-ray spectroscopic study of the transfermium nucleus 254No. The experiment was carried out at the Department of Physics of the University of Jyväskylä and utilised the JUROGAM array of germanium detectors coupled to the gas-filled recoil separator RITU. The ground-state rotational band was extended and evidence for non-yrast states was observed for the first time. [ABSTRACT FROM AUTHOR]

Published
2005
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24. RDDS lifetime measurement with JUROGAM + RITU.

Author

Grahn, T., Dewald, A., Möller, O., Beausang, C. W., Eeckhaudt, S., Greenlees, P. T., Jolie, J., Jones, P., Julin, R., Juutinen, S., Kettunen, H., Kröll, T., Krücken, R., Leino, M., Leppänen, A.-P., Maierbeck, P., Meyer, D. A., Nieminen, P., Nyman, M., and Pakarinen, J.

Subjects
*NUCLEAR energy, *NEUTRONS, *NUCLEAR structure, *NUCLEAR physics, *PHYSICS
Abstract

Lifetimes in 188Pb were measured using the Köln plunger in combination with the RITU separator and JUROGAM. Four lifetimes were measured, from which the deformation of the prolate band was experimentally determined for the first time. The squared prolate mixing amplitude of the 21+ state was deduced from the measured B( E2) values. [ABSTRACT FROM AUTHOR]

Published
2005
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25. Probing the three shapes in 186Pb using in-beam γ-ray spectroscopy.

Author

Pakarinen, J., Darby, I., Eeckhaudt, S., Enqvist, T., Grahn, T., Greenlees, P., Johnston-Theasby, F., Jones, P., Julin, R., Juutinen, S., Kettunen, H., Leino, M., Leppänen, A.-P., Nieminen, P., Nyman, M., Page, R., Raddon, P., Rahkila, P., Scholey, C., and Uusitalo, J.

Subjects
DELAYED neutrons, BETA decay, SPECTRUM analysis, NUCLEAR physics, PHYSICS
Abstract

This measurement represents the first observation of a non-yrast band in the 186Pb nucleus by employing the Recoil-Decay Tagging (RDT) technique. Previously known yrast levels have been confirmed and the band is extended up to level Iπ = (16+). [ABSTRACT FROM AUTHOR]

Published
2005
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26. Experimental study of 1/2+ isomers in 199,201 At.

Author

Auranen, K., Uusitalo, J., Juutinen, S., Jakobsson, U., Grahn, T., Greenlees, P. T., Hauschild, K., Herzá, A., Julin, R., Konki, J., Leino, M., Pakarinen, J., Partanen, J., Peura, P., Rahkila, P., Ruotsalainen, P., Sandzelius, M., Sarén, J., Scholey, C., and Sorri, J.

Subjects
*PROTONS, *ATOMIC number, *HEAVY ion fusion reactions, *RADIOACTIVE decay, *NUCLEAR physics
Abstract

The article discusses how exciting a proton from the s orbital across the atom with proton number 82 shell gap can create γ +intruder state in atom. It mentions that several methods such as fusion-evaporation reactions, a gas-filled recoil separator, and recoil-electron and recoil-electron-a tagging techniques, is applied to examine the effect. Information on isomer decays is also discussed.

Published
2014

27. Lifetime measurements in the transitional nucleus 138Gd.

Author

Procter, M. G., Cullen, D. M., Ruotsalainen, P., Braunroth, T., Dewald, A., Fransen, C., Grahn, T., Greenlees, P. T., Hackstein, M., Hauschild, K., Jakobsson, U., Jones, P. M., Julin, R., Juutinen, S., Ketelhut, S., Lopez-Martens, A., Leino, M., Litzinger, J., Mason, P. J. R., and Nieminen, P.

Subjects
*PHASE transitions, *STATISTICAL physics, *POTENTIAL energy surfaces, *QUANTUM chemistry, *NUCLEAR physics
Abstract

Lifetime measurements have been made in the ground-state band of the transitional nucleus 138Gd from coincidence recoil-distance Doppler-shift data. 138Gd nuclei were produced using the 106Cd (36Ar, 2p2n) reaction with a beam energy of 190 MeV. Reduced transition probabilities have been extracted from the lifetime data collected with the Köln plunger placed at the target position of the JUROGAM-II array. The B(E2) values have been compared with predictions from X(5) critical-point calculations, which describe the phase transition between vibrational and axially symmetric nuclear shapes, as well as with IBM-1 calculations at the critical point. While the excitation energies in 138Gd are consistent with X(5) predictions, the large uncertainties associated with the measured B(E2) values cannot preclude vibrational and rotational contributions to the low-lying structure of 138Gd. Although experimental knowledge for the low-lying γ and β-vibrational bands in 138Gd is limited, potential-energy surface calculations suggest an increase in γ softness in the ground-state band. In order to more fully account for the effects of γ softness, the X(5) and IBM-1 calculations need to be extended to include the γ degree of freedom for 138Gd. [ABSTRACT FROM AUTHOR]

Published
2011
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28. Combined in-beam electron and γ-ray spectroscopy of 184,186Hg.

Author

Scheck, M., Butler, P. A., Gaffney, L. P., Bree, N., Carrol, R. J., Cox, D., Grahn, T., Greenlees, P. T., Hauschild, K., Herzan, A., Huyse, M., Jakobsson, U., Jones, P., Joss, D. T., Julin, R., Juutinen, S., Ketelhut, S., Herzberg, R.-D., Kowalczyk, M., and Larsen, A. C.

Subjects
*NUCLEAR excitation, *SPECTROMETERS, *SPECTRUM analysis, *ELECTRONS, *NUCLEAR fusion, *NUCLEAR physics
Abstract

By exploiting the SAGE spectrometer a simultaneous measurement of conversion electrons and γ rays emitted in the de-excitation of excited levels in the neutron-deficient nuclei 184,186Hg was performed. The light Hg isotopes under investigation were produced using the 4n channels of the fusion-evaporation reactions of 40Ar and 148,150Sm. The measured K- and L-conversion electron ratios confirmed the stretched E2 nature of several transitions of the yrast bands in 184,186Hg. Additional information on the E0 component of the 22+→21+ transition in 186Hg was obtained. [ABSTRACT FROM AUTHOR]

Published
2011
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29. Probing the limit of nuclear existence: Proton emission from 159Re

Author

Joss, D.T., Darby, I.G., Page, R.D., Uusitalo, J., Eeckhaudt, S., Grahn, T., Greenlees, P.T., Jones, P.M., Julin, R., Juutinen, S., Ketelhut, S., Leino, M., Leppänen, A.-P., Nyman, M., Pakarinen, J., Rahkila, P., Sarén, J., Scholey, C., Steer, A., and Cannon, A.J.

Subjects
*PARTICLES (Nuclear physics), *COLLISIONS (Nuclear physics), *NUCLEAR physics, *NUCLEAR reactions
Abstract

Abstract: The observation of the new nuclide 159 75Re84 provides important insights into the evolution of single-particle structure and the mass surface in heavy nuclei beyond the proton drip line. This nuclide, 26 neutrons away from the nearest stable rhenium isotope, was synthesised in the reaction 106Cd(58Ni, ) and identified via its proton radioactivity using the ritu gas-filled separator and the great focal-plane spectrometer. Comparisons of the measured proton energy () and decay half-life () with values calculated using the WKB method indicate that the proton is emitted from an state. The implications of these results for future experimental investigations into even more proton unbound nuclei using in-flight separation techniques are considered. [Copyright &y& Elsevier]

Published
2006
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30. Recoil-beta tagging: A novel technique for studying proton-drip-line nuclei

Author

Steer, A.N., Jenkins, D.G., Glover, R., Nara Singh, B.S., Pattabiraman, N.S., Wadsworth, R., Eeckhaudt, S., Grahn, T., Greenlees, P.T., Jones, P., Julin, R., Juutinen, S., Leino, M., Nyman, M., Pakarinen, J., Rahkila, P., Sarén, J., Scholey, C., Sorri, J., and Uusitalo, J.

Subjects
*ENGINEERING instruments, *PHYSICS instruments, *OPTICS, *NUCLEAR physics
Abstract

Abstract: Tagging with charged particles and -rays at the focal plane of recoil separators has proven, over the last two decades, to be a very powerful tool for the identification of excited states in exotic nuclei produced with very low cross-sections. One of the key areas so far unexplored in terms of the tagging methodology has been performing correlations with -particles at the focal plane of a recoil separator. A new technique entitled Recoil-Beta Tagging (RBT) has been developed, this technique exploits the unusual properties of Fermi super-allowed emitters, which have both a short half-life () and high -endpoint energy. Correlating with such -particles using a double-sided silicon strip detector and planar germanium detector as an effective telescope for high-energy positrons has allowed a proof-of-principle of this technique to be carried out, by cleanly identifying excited states in the proton-drip-line nucleus, 74Rb. [Copyright &y& Elsevier]

Published
2006
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31. In-beam spectroscopy using the JYFL gas-filled magnetic recoil separator RITU

Author

Uusitalo, J., Jones, P., Greenlees, P., Rahkila, P., Leino, M., Andreyev, A.N., Butler, P.A., Enqvist, T., Eskola, K., Grahn, T., Herzberg, R.-D., Hessberger, F., Julin, R., Juutinen, S., Keenan, A., Kettunen, H., Kuusiniemi, P., Leppänen, A-P., Nieminen, P., and Page, R.

Subjects
*SPECTRUM analysis, *HEAVY ions, *RADIOACTIVE decay, *NUCLEAR physics
Abstract

The techniques of recoil-gating and recoil-decay tagging have been employed at Jyva¨skyla¨ to perform in-beam γ-ray and electron spectroscopy studies of heavy nuclei. The JUROSPHERE γ-ray array and the SACRED electron spectrometer have been placed at the target position of the JYFL gas-filled recoil separator recoil ion transport unit (RITU). The RITU separator has been used to collect the recoils of interest and separate them from beam particles and fission products. At the focal plane a detector system consisting of time-of-flight and implantation detectors has been used for further event identification. The method and some highlights from the results in the lead region close to the proton drip line and in the transuranium region will be presented and discussed. [Copyright &y& Elsevier]

Published
2003
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32. Towards saturation of the electron-capture delayed fission probability: The new isotopes $^{240}Es$ and $^{236}Bk$

Author

Rauno Julin, J. Khuyagbaatar, Bettina Lommel, Juha Sorri, Kalle Auranen, R. Briselet, Philippos Papadakis, R-D Herzberg, Paul Greenlees, K. Hauschild, Pauli Peura, J. Krier, Katsuhisa Nishio, Panu Rahkila, S. Juutinen, Sanna Stolze, Joonas Konki, B. Sulignano, Michael Block, Egon Jäger, Ch. Theisen, Mahananda Dasgupta, Alexander Yakushev, Tuomas Grahn, M. J. Mallaburn, Jari Partanen, K. Rezynkina, Janne Pakarinen, A. Ward, Andrej Herzan, Duc Huy Luong, Mikael Sandzelius, David Hinde, V. Yakusheva, Panu Ruotsalainen, Juha Uusitalo, Daniel Cox, A. Di Nitto, Jan Sarén, H. Badran, Ch. E. Düllmann, Birgit Kindler, F. P. Heßberger, A. Lopez-Martens, Matti Leino, C. Scholey, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Konki, J., Khuyagbaatar, J., Uusitalo, J., Greenlees, P. T., Auranen, K., Badran, H., Block, M., Briselet, R., Cox, D. M., Dasgupta, M., Di Nitto, A., Dullmann, C. E., Grahn, T., Hauschild, K., Herzan, A., Herzberg, R. -D., Hessberger, F. P., Hinde, D. J., Julin, R., Juutinen, S., Jager, E., Kindler, B., Krier, J., Leino, M., Lommel, B., Lopez-Martens, A., Luong, D. H., Mallaburn, M., Nishio, K., Pakarinen, J., Papadakis, P., Partanen, J., Peura, P., Rahkila, P., Rezynkina, K., Ruotsalainen, P., Sandzelius, M., Saren, J., Scholey, C., Sorri, J., Stolze, S., Sulignano, B., Theisen, C., Ward, A., Yakushev, A., and Yakusheva, V.

Subjects
Electron-capture delayed fission, Nuclear and High Energy Physics, Electron capture, Fission, Fusion–evaporation reaction, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 236 Bk, 01 natural sciences, 7. Clean energy, Recoil separator, Nuclear physics, fusion-evaporation reactions, 236Bk, 240Es, 240 Es, 0103 physical sciences, ddc:530, 010306 general physics, α decay, isotopes, Physics, Isotope, ta114, Isotopes with mass 236–240, 010308 nuclear & particles physics, lcsh:QC1-999, Exponential function, Bk, mass, Atomic physics, Saturation (chemistry), Fusion–evaporation reactions, α particles, lcsh:Physics, Radioactive decay
Abstract

The new neutron-deficient nuclei 240 Es and 236 Bk were synthesised at the gas-filled recoil separator RITU. They were identified by their radioactive decay chains starting from 240 Es produced in the fusion–evaporation reaction 209 Bi( 34 S,3n) 240 Es. Half-lives of 6 ( 2 ) s and 22 − 6 + 13 s were obtained for 240 Es and 236 Bk, respectively. Two groups of α particles with energies E α = 8.19 ( 3 ) MeV and 8.09 ( 3 ) MeV were unambiguously assigned to 240 Es. Electron-capture delayed fission branches with probabilities of 0.16 ( 6 ) and 0.04 ( 2 ) were measured for 240 Es and 236 Bk, respectively. These new data show a continuation of the exponential increase of ECDF probabilities in more neutron-deficient isotopes.

Published
2017

33. Decays of new nuclides and isomers beyond the proton drip line - The influence of neutron configurations

Author

R. D. Page, L. Bianco, I. G. Darby, D. T. Joss, J. Simpson, J. S. Al-Khalili, A. J. Cannon, R. J. Cooper, S. Eeckhaudt, S. Ertürk, B. Gall, T. Grahn, P. T. Greenlees, B. Hadinia, P. M. Jones, D. S. Judson, R. Julin, S. Juutinen, S. Ketelhut, M. Labiche, M. Leino, A.-P. Leppänen, M. Nyman, D. O’Donnell, P. Rahkila, P. J. Sapple, J. Sarén, C. Scholey, A. N. Steer, P. D. Stevenson, E. B. Suckling, J. Thomson, J. Uusitalo, M. Venhart, Ismail Boztosun, A. B. Balantekin, 0-Belirlenecek, and Page, R.D., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Bianco, L., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Darby, I.G., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Joss, D.T., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Simpson, J., STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom -- Al-Khalili, J.S., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Cannon, A.J., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Cooper, R.J., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Eeckhaudt, S., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Ertürk, S., Nigde Universitesi, Fen-Edebiyat Falkultesi, Fizik Bdlumti, Nigde, Turkey -- Gall, B., IPHC, CNRS, IN2P3, ULP Strasbourg, 23 rue de Loess, Strasbourg, 67037, France -- Grahn, T., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Greenlees, P.T., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Hadinia, B., Royal Institute of Technology, Alba Nova Center, Stockholm, S-106 91, Sweden -- Jones, P.M., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Judson, D.S., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Julin, R., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Juutinen, S., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Ketelhut, S., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Labiche, M., STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom -- Leino, M., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Leppänen, A.-P., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Nyman, M., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- O'Donnell, D., STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom -- Rahkila, P., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Sapple, P.J., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Sarén, J., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Scholey, C., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Steer, A.N., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Stevenson, P.D., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Suckling, E.B., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Thomson, J., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Uusitalo, J., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Venhart, M., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland

Subjects
Physics, Proton, Gamma ray, Alpha particle, Segmented Si and Ge detectors. Measured E ? ,E proton ,E ? ,T 1/2, Nuclear physics, Nuclear Reactions 58 Ni+ 106 Cd at 290,300,310 MeV beam energy, Beta particle, Neutron, Enriched targets, Nuclide, Alpha decay, Gas-filled recoil separator, Atomic physics, Nuclear Experiment, Ground state
Abstract

Bozok University;Erciyes University;et al.;Istanbul University;Nigde University;The Turkish Atomic Energy Authority (TAEK), International Conference on Nuclear Physics and Astrophysics: From Stable Beams to Exotic Nuclei 2008 -- 25 June 2008 through 30 June 2008 -- -- 139817, The energy of the vh 9/2 orbital in nuclei above N = 82 drops rapidly in energy relative to the vf 7/2 orbital as the occupancy of the ?h 11/2 orbital increases. These two neutron orbitals become nearly degenerate as the proton drip line is approached. In this work, we have discovered the new nuclides 161 Os and 157 W, and studied the decays of the proton emitter 160 Re in detail. The 161 Os and 160 Re nuclei were produced in reactions of 290, 300 and 310 MeV 58 Ni ions with an isotopically enriched 106 Cd target, separated in-flight using the RITU separator and implanted into the GREAT spectrometer. The 161 Os a decays populated the new nuclide 157 W, which decayed by ß-particle emission. The ß decay fed the known ?-decaying l/2 + and 11/2 - states in 157 Ta, which is consistent with a vf 7/2 ground state in 157 W. The measured a-decay energy and half-life for 161 Os correspond to a reduced ?-decay width that is compatible with s-wave ?-particle emission, implying that its ground state is also a vf 7/2 state. Over 7000 160 Re nuclei were produced and the y decays of a new isomeric state feeding the ?d 3/2 level in 160 Re were discovered, but no evidence for the proton or a decay of the expected ?h 11/2 state could be found. The isomer decays offer a natural explanation for this non-observation and provides a striking example of the influence of the near degeneracy of the vh 9/2 and vf 7/2 orbitals on the properties of nuclei in this region. © 2008 American Institute of Physics., Academy of Finland Science and Technology Facilities Council Finnish Centre of Excellence in Atomic Layer Deposition Natural Sciences and Engineering Research Council of Canada, We would like to thank the technical staff at Jyvaskyla for their excellent support and to Paul Morrall from Daresbury Laboratory for making the targets. This work has been supported by the UK Science and Technology Facilities Council; the Swedish Natural Science Research Council; the Academy of Finland under the Finnish Centre of Excellence Programme (project 44875 Nuclear and Condensed Matter Physics Programme at JYFL); the European Union Sixth Framework contract EURONS (RII3-CT-2004-506065) and the European Union Marie Curie Programme (contract HPMT-CT-2001-00250).

Published
2008

34. Discovery of the proton emitting nucleus $^{159}$Re

Author

D. T. Joss, I. G. Darby, R. D. Page, J. Uusitalo, S. Eeckhaudt, T. Grahn, P. T. Greenlees, P. M. Jones, R. Julin, S. Juutinen, S. Ketelhut, M. Leino, A.-P. Leppänen, M. Nyman, J. Pakarinen, P. Rahkila, J. Sarén, C. Scholey, A. N. Steer, J. S. Al-Khalili, A. J. Cannon, P. D. Stevenson, S. Ertürk, B. Gall, B. Hadinia, M. Venhart, J. Simpson, Lídia S. Ferreira, Paramasivan Arumugan, Département Recherches Subatomiques (DRS-IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Lídia S. Ferreira, Paramasivan Arumugan, Joss, D.T., Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom, STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom -- Darby, I.G., Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Page, R.D., Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Uusitalo, J., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Eeckhaudt, S., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Grahn, T., Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Greenlees, P.T., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Jones, P.M., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Julin, R., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Juutinen, S., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Ketelhut, S., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Leino, M., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Leppänen, A.-P., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Nyman, M., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Pakarinen, J., Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Rahkila, P., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Sarén, J., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Scholey, C., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Steer, A.N., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Al-Khalili, J.S., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Cannon, A.J., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Stevenson, P.D., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Ertürk, S., Nigde Universitesi, Fen-Edebiyat Falkültesi, Fizik Bölümü, Nigde, Turkey -- Gall, B., ULP Strasbourg, 23 rue du Loess, 67037 Strasbourg Cedex 2, France -- Hadinia, B., Department of Physics, Royal Institute of Technology, SE-10691, Stockholm, Sweden -- Venhart, M., Department of Nuclear Physics and Biophysics, Comenius University, Mlynska Dolina, 842 48, Bratislava 4, Slovakia -- Simpson, J., STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom, and 0-Belirlenecek

Subjects
Si detectors, nuclear spin, Measured E p, Proton, Hadron, 02 engineering and technology, rhenium, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, Nuclear physics, Isotopes of cadmium, 0202 electrical engineering, electronic engineering, information engineering, nuclei with mass number 150 to 189, Enriched targets, radioactive decay periods, Nuclide, Isotope, Chemistry, Nuclear structure, 020206 networking & telecommunications, T1/2, 13. Climate action, 020201 artificial intelligence & image processing, 23.50.+z, 27.70.+q, 21.10.Tg, 21.10.Hw, Gas-filled recoil separator, Nucleon, Radioactive decay, Nuclear reactions 58Ni + 106Cd at 300 MeV beam energy, proton emission decay
Abstract

Fund. para Cienc. Tecnol., FCT, Minist. Cienc. Tecnol.;Fundacao Calouste Gulbenkian;Fundacao Luso-Americana, International Conference on Proton Emitting Nuclei and Related Topics, PROCON 2007 -- 17 June 2007 through 23 June 2007 -- Lisbon, The observation of the new nuclide 159Re provides important insights into the evolution of single-particle structure in heavy nuclei beyond the proton drip line. The nuclide 159Re was synthesised in the reaction 106Cd(58Ni, p4n) and identified via its proton radioactivity using the RITU gas-filled separator and the GREAT focal-plane spectrometer. Comparisons of the measured proton energy (Ep = 1805±20 keV) and decay half-life (t1/2 = 21±4 µs) with values calculated using the WKB method indicate that the proton is emitted from an h11/2 state. The implications of these results for future experimental investigations into even more proton unbound Re isotopes using in-flight separation techniques are considered. © 2007 American Institute of Physics.

Published
2007

35. Probing single-particle structures beyond the proton drip line

Author

R. D. Page, L. Bianco, I. G. Darby, D. T. Joss, T. Grahn, R.-D. Herzberg, J. Pakarinen, J. Thomson, J. Uusitalo, S. Eeckhaudt, P. T. Greenlees, P. M. Jones, R. Julin, S. Juutinen, S. Ketelhut, M. Leino, A.-P. Leppänen, M. Nyman, P. Rahkila, J. Sarén, C. Scholey, A. Steer, M. Venhart, J. Simpson, J. S. Al-Khalili, A. J. Cannon, P. D. Stevenson, S. Ertürk, B. Gall, B. Hadinia, Lídia S. Ferreira, Paramasivan Arumugan, Département Recherches Subatomiques (DRS-IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Lídia S. Ferreira, Paramasivan Arumugan, Ferreira, LS, Arumugam, P, Scholey, Catherine -- 0000-0002-8743-6071, Stevenson, Paul -- 0000-0003-2645-2569, Pakarinen, Janne -- 0000-0001-8944-8757, Grahn, Tuomas -- 0000-0002-6255-2279, Jones, Pete -- 0000-0001-7480-6603, and [Page, R. D. -- Bianco, L. -- Darby, I. G. -- Joss, D. T. -- Grahn, T. -- Herzberg, R. -D. -- Pakarinen, J. -- Thomson, J.] Univ Liverpool, Dept Phys, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England -- [Uusitalo, J. -- Eeckhaud, S. -- Greenlees, P. T. -- Jones, P. M. -- Julin, R. -- Juutinen, S. -- Ketelhut, S. -- Leino, M. -- Leppanen, A. -P. -- Nyman, M. -- Rahkila, P. -- Saren, J. -- Scholey, C. -- Steer, A. -- Venhart, M.] Univ jyvaskyla, Dept Phys, FIN-40014 Jyvaskyla, Finland -- [Simpson, J.] STFC, Daresbury Lab, Warrington WA4 4AD, Cheshire, England -- [Al-Khalili, J. S. -- Cannon, A. J. -- Stevenson, P. D.] Univ Surrey, Dept Phys, Guildford GU2 7XH, Surrey, England -- [Erturk, S.] Nigde Univ, Nigde, Turkey -- [Gall, B.] ULP Strasbourg, CNRS IN2P, IPHC, F-67037 Strasbourg 2, France -- [Hadinia, B.] AlbaNova Univ Ctr, Royal Inst Technol, S-10691 Stockholm, Sweden

Subjects
Proton, Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Nuclear physics, 0103 physical sciences, nuclei with mass number 150 to 189, Neutron, alpha-decay, radioactive decay periods, Proton emission, branching ratio. Re-159, 010306 general physics, Nuclear Experiment, Physics, RADIOACTIVITY Re-159(alpha)[from Cd-106(Ni-58,p4n)], Ta-155 deduced levels, Ta-155(p)[from Re-159 a decay], 010308 nuclear & particles physics, Alpha particle, previous Ta-155 study, Charged particle, comparisons with neighbouring nuclides, measured E-alpha, E-p, T-1/2, 23.50.+z, 23.60.+e, 27.70.+q, J, pi configurations, Alpha decay, Atomic physics, Nucleon, Radioactive decay, proton emission decay
Abstract

International Conference on Proton Emitting Nuclei and Related Topics -- JUN 17-23, 2007 -- Lisbon, PORTUGAL, WOS: 000252267300021, Single-particle energies have been investigated in the closed neutron shell proton emitter Ta-155. The Ta-155 nuclei were populated through the alpha decay of Re-159, which has been observed for the first time. The (159)Rc nuclei were produced in reactions of 300 MeV Ni-58 ions with an isotopically enriched Cd-106 target, separated in-flight using the RITU separator and implanted into the GREAT spectrometer. The Re-159 a decay emanates from the proton-emitting pi h(11/2) state and populates a state in Ta-155 which decays by the emission of a proton from a pi h(11/2) orbital. The results fit in with the systematics of proton and alpha-particle separation energies in the region, but disagree with the previously reported decay properties of Ta-155., Fundacao Ciencia & Tecnol, Minist Ciencia & Tecnol, Fundacao Calouste Gulbenklan, Fundacao Luso Americana, UK Engineering and Physical Sciences Research Council; Swedish Natural Science Research Council; Academy of Finland under the Firmish Centre of Excellence Programme (project 44875 Nuclear and Condensed Matter Physics Programme at JYFL); European Union Sixth Framework contract EURONS [RII3-CT-2004-506065]; European Union Marie Curie Programme [HPMT-CT-2001-00250], The authors would like to thank the technical staff at the Accelerator Laboratory at the University of Jyvaskyla for their excellent support and to Paul Morrall from Daresbury Laboratory for making the targets. This work has been supported by the UK Engineering and Physical Sciences Research Council; the Swedish Natural Science Research Council; the Academy of Finland under the Firmish Centre of Excellence Programme (project 44875 Nuclear and Condensed Matter Physics Programme at JYFL); the European Union Sixth Framework contract EURONS (contract RII3-CT-2004-506065) and the European Union Marie Curie Programme (contract HPMT-CT-2001-00250).

Published
2007

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