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36 results on '"GELLETLY, W."'

2. Updated Summation Model: An Improved Agreement with the Daya Bay Antineutrino Fluxes

Author

Estienne, M., Fallot, M., Algora, A., Briz-Monago, J., Bui, V. M., Cormon, S., Gelletly, W., Giot, L., Guadilla, V., Jordan, D., Meur, L. Le, Porta, A., Rice, S., Rubio, B., Ta��n, J. L., Valencia, E., Zakari-Issoufou, A. -A., SUBATECH, CNRS/IN2P3, de Nantes, Universit��, de Nantes, Institut Mines-Telecom, Nantes, France, IFIC, Valencia, Spain, Research, Institute of Nuclear, Debrecen, Hungary, Physics, Department of, Surrey, University of, Guildford, Laboratoire de physique subatomique et des technologies associées (SUBATECH), Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Ministerio de Economía y Competitividad (España), and Ministerio de Ciencia, Innovación y Universidades (España)

Subjects
Spectral shape analysis, Fission, 28.41.Ak, General Physics and Astronomy, FOS: Physical sciences, anomaly, 28.50.Hw, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], gamma ray: absorption, 7. Clean energy, 01 natural sciences, Spectral line, 14.60.Pq, renormalization, 23.40.-s, Nuclear physics, Renormalization, 0103 physical sciences, Daya Bay, antineutrino: nuclear reactor, fission, Absorption (logic), Nuclear Experiment (nucl-ex), 010306 general physics, Spectroscopy, Nuclear Experiment, Nuclear Physics, Physics, Range (particle radiation), antineutrino: spectrum, antineutrino: flux, antineutrino: energy spectrum, 28.41.-i, spectral, data management, Anomaly (physics)
Abstract

A new summation method model of the reactor antineutrino energy spectrum is presented. It is updated with the most recent evaluated decay databases and with our Total Absorption Gamma-ray Spectroscopy measurements performed during the last decade. For the first time the spectral measurements from the Daya Bay experiment are compared with the detected antineutrino energy spectrum computed with the updated summation method without any renormalisation. The results exhibit a better agreement than is obtained with the Huber-Mueller model in the 2 to 5 MeV range, the region which dominates the detected flux. An unexpected systematic trend is found that the detected antineutrino flux computed with the summation model decreases with the inclusion of more Pandemonium free data. The detected flux obtained now lies only 1.9% above that detected in the Daya Bay experiment, a value that may be reduced with forthcoming new Pandemonium free data leaving less and less room to the reactor anomaly. Eventually, the new predictions of individual antineutrino spectra for the $^{235}$U, $^{239}$Pu, $^{241}$Pu and $^{238}$U are used to compute the dependence of the reactor antineutrino spectral shape on the fission fractions., Comment: 12 pages, 4 figures

Published
2019
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3. Large Impact of the Decay of Niobium Isomers on the Reactor ${\overline{{\nu}}}_{e}$ Summation Calculations

Author

Guadilla, V., Algora, A., Tain, J.L., Estienne, Magali, Fallot, Muriel, Sonzogni, A.A., Agramunt, J., Äystö, J., Briz, J.A., Cucoanes, A., Eronen, T., Fraile, L.M., Ganioğlu, E., Gelletly, W., Gorelov, D., Hakala, J., Jokinen, A., Jordan, D., Kankainen, A., Kolhinen, V., Koponen, J., Lebois, M., Le Meur, L., Martinez, T., Monserrate, M., Montaner-Pizá, A., Moore, I., Nácher, E., Orrigo, S.E.A., Penttilä, H., Pohjalainen, I., Porta, Amanda, Reinikainen, J., Reponen, M., Rinta-Antila, S., Rubio, B., Rytkönen, K., Shiba, T., Sonnenschein, V., Valencia, E., Vedia, V., Voss, A., Wilson, J.N., Zakari-Issoufou, A.A., Laboratoire de physique subatomique et des technologies associées (SUBATECH), Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Institut de Physique Nucléaire d'Orsay (IPNO), 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), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and 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)

Subjects
Penning trap, energy: ground state, particle separator, antineutrino: nuclear reactor, semileptonic decay, antineutrino: energy spectrum, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment, niobium, experimental results, energy: transition, Nuclear Physics
Abstract

International audience; Even mass neutron-rich niobium isotopes are among the principal contributors to the reactor antineutrino energy spectrum. They are also among the most challenging to measure due to the refractory nature of niobium, and because they exhibit isomeric states lying very close in energy. The β-intensity distributions of Nb100gs,100m and Nb102gs,102m β decays have been determined using the total absorption γ-ray spectroscopy technique. The measurements were performed at the upgraded Ion Guide Isotope Separator On-Line facility at the University of Jyväskylä. Here, the double Penning trap system JYFLTRAP was employed to disentangle the β decay of the isomeric states. The new data obtained in this challenging measurement have a large impact in antineutrino summation calculations. For the first time the discrepancy between the summation model and the reactor antineutrino measurements in the region of the shape distortion has been reduced.

Published
2019
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4. Beta-decay studies for applied and basic nuclear physics.

Author

Algora, A., Tain, J. L., Rubio, B., Fallot, M., and Gelletly, W.

Subjects
NUCLEAR physics, NUCLEAR models, NEUTRON temperature, NEUTRON emission, NEUTRON capture, NUCLEAR structure, NUCLEAR reactors, NUCLEAR astrophysics
Abstract

In this review we will present the results of recent β -decay studies using the total absorption technique that cover topics of interest for applications, nuclear structure and astrophysics. The decays studied were selected primarily because they have a large impact on the prediction of (a) the decay heat in reactors, important for the safety of present and future reactors and (b) the reactor electron anti-neutrino spectrum, of interest for particle/nuclear physics and reactor monitoring. For these studies the total absorption technique was chosen, since it is the only method that allows one to obtain β -decay probabilities free from a systematic error called the Pandemonium effect. The total absorption technique is based on the detection of the γ cascades that follow the initial β decay. For this reason the technique requires the use of calorimeters with very high γ detection efficiency. The measurements presented and discussed here were performed mainly at the IGISOL facility of the University of Jyväskylä (Finland) using isotopically pure beams provided by the JYFLTRAP Penning trap. Examples are presented to show that the results of our measurements on selected nuclei have had a large impact on predictions of both the decay heat and the anti-neutrino spectrum from reactors. Some of the cases involve β -delayed neutron emission thus one can study the competition between γ - and neutron-emission from states above the neutron separation energy. The γ -to-neutron emission ratios can be used to constrain neutron capture (n, γ ) cross sections for unstable nuclei of interest in astrophysics. The information obtained from the measurements can also be used to test nuclear model predictions of half-lives and Pn values for decays of interest in astrophysical network calculations. These comparisons also provide insights into aspects of nuclear structure in particular regions of the nuclear chart. [ABSTRACT FROM AUTHOR]

Published
2021
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5. Enhanced gamma-ray emission from neutron unbound states populated in beta decay

Author

Taín Enríquez, José Luis, Valencia, E., Algora, A., Rubio, B., Maurice, S., Gelletly, W., Fallot, M., Rissanen, J., Eronen, T., Äystö, J., Batist, L., Bowry, M., Caballero Folch, Roger, Gómez Hornillos, María Belén, Gorlychev, V., Mendoza, E., Moore, I., Penttila, H., Reponen, M., Sonnenschein, V., and Universitat Politècnica de Catalunya. ANT - Advanced Nuclear Technologies Research Group

Subjects
Competition, Física [Àrees temàtiques de la UPC], Penning trap, BR-87, education, Nuclear physics, Spectrum analysis, Total absorption-spectra, Nuclear-data sheets, Schemes, Física nuclear, Jyfltrap, Spectroscopy, Purification, Simulation
Published
2015

6. Studies of Single-Particle Structure in the N=16 Region Using Transfer Reactions

Author

Lemmon, R. C., Beatriz Fernandez Dominguez, Timis, C., Labiche, M., Catford, W. N., Chartier, M., Ashwood, N., Amzal, N., Baldwin, T. D., Burns, M., Caballero, L., Chapman, R., Curtis, N., France, G., Freer, M., Gelletly, W., Liang, X., Orr, N. A., Pain, S. D., Pucknell, V. P. E., Rejmund, M., Rubi, B., Savajols, H., Sarlin, O., Spohr, K., Thiesen, C., Warner, D. D., Instituto de Fisica Corpuscular (IFIC), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universitat de València (UV), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut de Physique Nucléaire d'Orsay (IPNO), 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), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), L.Corradi, D. Ackermann, E. Fioretto, A. Gadea, F. Haas, G. Pollarolo, F. Scarlassara, Suzana Szilner, M. Trotta, EXOGAM, SPIRAL, VAMOS, Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), 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), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear reaction, nuclei with mass number 20 to 38, Spectrometer, Cyclotron, Hadron, 020206 networking & telecommunications, Elementary particle, 02 engineering and technology, Fermion, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], law.invention, Nuclear physics, law, nuclear structure, 0202 electrical engineering, electronic engineering, information engineering, Measuring instrument, deuteron-nucleus reactions, 21.10.Pc, 25.45.Hi, 27.30.+t, 020201 artificial intelligence & image processing, neon, Nuclear Experiment, Nucleon
Abstract

International audience; We have developed a new experimental setup based at the GANIL/SPIRAL facility in Caen, France to measure one-nucleon transfer reactions in inverse kinematics in order to study the evolution of the single particle structure of exotic nuclei. The setup couples together three state-of-the-art detection systems: the TIARA Si array, the large-acceptance magnetic spectrometer VAMOS and the high-efficiency segmented Ge gamma-ray array EXOGAM. In a first experiment, the $^{24}$Ne(d,p)$^{25}$Ne reaction has been studied to probe the N=16 shell closure. Details of the setup, data analysis and preliminary results are presented.

Published
2006
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7. Studies of the Single Particle Structure of Exotic Nuclei using Transfer Reactions

Author

Fernandez-Dominguez, B., Lemmon, R. C., Timis, C., Labiche, A., Catford, W. N., Chartier, M., Ashwood, N., Amzal, N., Baldwin, T. D., Burns, M., Caballero, L., Chapman, R., Curtis, N., France, G., Freer, M., Gelletly, W., Liang, X., Orr, N. A., Steven Pain, Pucknellt, V. P. E., Rejmund, M., Rubio, B., Savajols, H., Sorlin, O., Spohr, K., Thiesen, C., Warner, D. D., Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut de Physique Nucléaire d'Orsay (IPNO), 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), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), S.V. Harissopulos, P. Demetriou, E. Julin, EXOGAM, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and 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)

Subjects
Physics, nuclei with mass number 20 to 38, spectrometers, Spectrometer, germanium radiation detectors, 21.10.Pc, 25.60.Je, 27.30.+t, 29.30.-h, 29.40.Wk, Nuclear structure, chemistry.chemical_element, 020206 networking & telecommunications, 02 engineering and technology, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Semiconductor detector, Nuclear physics, Neon, Germanium radiation detectors, Deuterium, chemistry, nuclear structure, 0202 electrical engineering, electronic engineering, information engineering, Particle, 020201 artificial intelligence & image processing, neon, Nuclear Experiment, Beam (structure)
Abstract

The TIARA+VAMOS+EXOGAM set-up has recently been installed at GANIL to study the single-particle structure of exotic nuclei. The unique characteristics of the TIARA array, combined with the large acceptance spectrometer VAMOS and the high efficiency Germanium detector array EXOGAM, has allowed high-resolution measurements of transfer reactions in inverse kinematics using low intensity exotic beams. We will describe the experimental set-up, data analysis and preliminary results of the first experiments using a $^{24}$Ne beam from SPIRAL, concentrating in particular on the performance of VAMOS that has been used to detect the heavy fragments after the (d,p), (d,d) and (d,t) reactions.

Published
2005
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8. Single-particle structure of radioactive beams from one-nucleon knockout reactions

Author

Navin, A, Aumann, T, Bazin, D, Brown, BA, Glasmacher, T, Hansen, PG, Ibbotson, RW, Maddalena, V, Sherrill, BM, Tostevin, JA, Yurkon, J, Rubio, B, Lozano, M, and Gelletly, W

Subjects
Momentum, Nuclear physics, Baryon, Nuclear reaction, Physics, Angular momentum, Projectile, Nuclear Theory, Hadron, Neutron, Atomic physics, Nuclear Experiment, Nucleon
Abstract

Studies of the single-particle structure of radioactive beams produced in fragmentation reactions are described. The experiments are based on observing the individual final states of the projectile residues produced in one-nucleon knockout reactions. The measured partial cross sections to the various final states of the projectile residue and the shape of the corresponding longitudinal momentum distributions reflect the single particle properties, spectroscopic factors and the angular momentum l of the removed nucleon. Applications to 26,27P and 15C are discussed.

Published
1999

9. GAMOW--TELLER EXCITATIONS STUDIED BY WEAK AND STRONG INTERACTIONS.

Author

FUJITA, Y., RUBIO, B., ADACHI, T., BLANK, B., FUJITA, H., GELLETLY, W., MOLINA, F., and ORRIGO, S. E. A.

Subjects
NUCLEAR structure, POTENTIAL barrier, NUCLEAR physics, NUCLEAR astrophysics, PARTICLES (Nuclear physics)
Abstract

Studying weak nuclear responses, especially the Gamow--Teller (GT) transitions starting from stable as well as unstable nuclei, provide crucial and critical information on nuclear structure. Therefore, the study of GT transitions is a key issue in nuclear physics and also nuclear-astrophysics. Under the assumption of isospin symmetry, it is expected that the structure of mirror nuclei and the GT transitions starting from their ground states are identical. We have studied the corresponding GT transitions starting from Tz = ±1 and ±2 pf-shell nuclei, respectively, by means of hadronic (³He, t) charge-exchange reactions and mirror β decays. The results on GT strength distributions measured in β decays and (³He, t) reactions performed at an intermediate incident energy of 140 MeV/nucleon and 0° are compared. The combined results help provide an understanding of nuclear structure of nuclei far-from-stability. [ABSTRACT FROM AUTHOR]

Published
2015
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10. 7Li-induced reactions for fast-timing with LaBr3:Ce detectors.

Author

Mason, P. J. R., Podolyàk, Zs., Mărginean, N., Regan, P. H., Alexander, T., Algora, A., Alharbi, T., Bowry, M., Britton, R., Bucurescu, D., Bruce, A. M., Bunce, M., Căta-Danil, G., Căta-Danil, I., Cooper, N., Deleanu, D., Delion, D., Filipescu, D., Gelletly, W., and Glodariu, T.

Subjects
LITHIUM isotopes, NUCLEAR reactions, LANTHANUM compounds, CERIUM, DETECTORS, NUCLEAR physics, GERMANIUM
Abstract

7Li induced-reactions have been used with a 186W target to populate nuclei around A∼180-190 at the National Institute of Physics and Nuclear Engineering in Bucharest, Romania. An array of high-purity germanium (HPGe) and cerium-doped lanthanum bromide (LaBr3:Ce) detectors have been used to measure sub-nanosecond half-lives with fast-timing techniques. The yrast 2+ state in 190Os was measured to be t1/2 = 375(20)ps, in excellent agreement with the literature value. The previously unreported half-life of the 564-keV state in 189Ir has also been measured and a value of t1/2 = 540(100)ps ps obtained. [ABSTRACT FROM AUTHOR]

Published
2012
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11. Beta decay of exotic TZ = -1 and TZ = -2 nuclei.

Author

Orrigo, S. E. A., Rubio, B., Fujita, Y., Blank, B., Gelletly, W., Agramunt, J., Algora, A., Ascher, P., Bilgier, B., Cáceres, L., Cakirli, R. B., Fujita, H., Ganioğlu, E., Gerbaux, M., Giovinazzo, J., Grévy, S., Kamalou, O., Kozer, H. C., Kucuk, L., and Kurtukian-Nieto, T.

Subjects
BETA decay, IRON isotopes, CHARGE exchange reactions, HALF-life (Nuclear physics), NUCLEAR physics, COMPARATIVE studies
Abstract

The half-lives of the TZ = -2, 56Zn and TZ = -1, 58Zn isotopes and other nuclei were measured in a β-decay experiment at GANIL. The energy levels populated by the 56Zn β decay were determined. The 56Zn results are compared with the results of the mirror process, the charge exchange reaction 56Fe(3He,t)56Co. [ABSTRACT FROM AUTHOR]

Published
2012
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12. Gamow-Teller Transitions Studied in (3He, t) Reaction and Analogous β decay.

Author

Fujita, Y., Rubio, B., Molina, F., and Gelletly, W.

Subjects
POTENTIAL barrier, NUCLEAR physics, NUCLEOSYNTHESIS, CHEMICAL elements, COSMOCHEMISTRY
Abstract

Due to the simplicity of the στ operator that causes Gamow-Teller (GT) transitions, they are the most popular nuclear weak process in the Universe. The GT transitions in pf-shell nuclei, for example, starting from stable Tz = +1 and proton-rich Tz = +1 nuclei, where Tz = (N-Z)/2, play important roles in the supernova-explosion or rp-process nucleosynthesis. In the β-decay study of pf-shell nuclei, half-lives can be measured rather accurately. On the other hand, in a high-resolution (3He, t) charge-exchange reaction at 0°, individual GT transitions up to high excitations can be studied. In order to derive reliable GT transition strengths B(GT), we present a unique analysis that combines the strength distribution form the (3He, t) measurement with the information from the study of mirror β decay, where good isospin symmetry of Tz = ±1→0 transitions is assumed. [ABSTRACT FROM AUTHOR]

Published
2010
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13. Comparison of Tz = ±1→0 GT Transitions.

Author

Molina, F., Rubio, B., Fujita, Y., and Gelletly, W.

Subjects
BETA decay, CHARGE exchange, NUCLEAR reactions, NUCLEAR physics, COLLISIONS (Nuclear physics)
Abstract

Gamow-Teller (GT) transitions can be studied in both β-decay and charge exchange(CE) reactions. If isospin is a good quantum number, then the Tz = -1→0 and Tz = +1→0 GT mirror transitions, are identical. Therefore, a comparison of the results from studies of β decay and CE should shed light on this assumption. Accordingly we have studied the β decay of the Tz = -1 fp-shell nuclei, 54Ni, 50Fe, 46Cr, and 42Ti, produced in fragmentation and we have compared our results with the spectra from (3He, t) measurements on the mirror Tz = +1 target nuclei studied in high resolution at RCNP, Osaka. The β-decay experiments were performed as part of the STOPPED beam RISING campaign at GSI. [ABSTRACT FROM AUTHOR]

Published
2010
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14. New Insights into the Structure of Exotic Nuclei Using the RISING Active Stopper.

Author

Regan, P. H., Alkhomashi, N., Al-Dahan, N., Podolyák, Zs., Suckling, E. B., Stevenson, P. D., Pietri, S. B., Steer, S. J., Garnsworthy, A. B., Gelletly, W., Benlliure, J., Morales, A. I., Gerl, J., Górska, M., Wollersheim, H. J., Kumar, R., Grebosz, J., Algora, A., Benzoni, G., and Boutachkov, P.

Subjects
NUCLEAR structure, BETA decay, NUCLEAR physics, GAMMA rays, SPECTRUM analysis, NEUTRONS, NUCLEAR shapes
Abstract

This conference paper outlines the operation and some of the preliminary physics results using the GSI RISING active stopper. Data are presented from an experiment using combined isomer and beta-delayed gamma-ray spectroscopy to study low-lying spectral and decay properties of heavy-neutron-rich nuclei around A∼190 produced following the relativistic projectile fragmentation of 208Pb primary beam. The response of the RISING active stopper detector is demonstrated for both the implantation of heavy secondary fragments and in-situ decay of beta-particles. Beta-delayed gamma-ray spectroscopy following decays of the neutron-rich nucleus 194Re is presented to demonstrate the experimental performance of the set-up. The resulting information inferred from excited states in the W and Os daughter nuclei is compared with results from Skyrme Hartree-Fock predictions of the evolution of nuclear shape. [ABSTRACT FROM AUTHOR]

Published
2009
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15. Structure of N>=126 nuclei produced in fragmentation of 238U.

Author

Al-Dahan, N., Podolyák, Zs., Regan, P. H., Steer, S. J., Alkhomashi, N., Bacelar, A. M. Denis, Górska, M., Pietri, S. B., Gelletly, W., Walker, P. M., Farrelly, G., Morales, A. I., Deo, A. Y., Cullen, I. J., Gerl, J., Domingo-Pardo, C., Verma, S., Swan, T., Wollersheim, H. J., and Bruce, A. M.

Subjects
NUCLEAR structure, NEUTRONS, SILICON, GAMMA rays, NUCLEAR physics, NEUTRON beams
Abstract

The nuclear structure of neutron-rich N>=126 nuclei have been investigated following their production via relativistic projectile fragmentation of a E/A = 1 GeV 238U beam on a Be target. The cocktail of secondary beam products were separated and identified using the GSI FRagment Separator (FRS). The nuclei of interest were implanted in a high-granularity active stopper detector set-up consisting of 6 double sided silicon strip detectors. The associated gamma-ray transitions were detected with the RISING array, consisting of 15 Euroball cluster Ge-detectors. Time-correlated gamma decays from individually identified nuclear species have been recorded, allowing the clean identification of isomeric decays. [ABSTRACT FROM AUTHOR]

Published
2009
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16. Gamow-Teller Transitions in Stable and Unstable pf-shell Nuclei.

Author

Fujita, Y., Rubio, B., and Gelletly, W.

Subjects
POTENTIAL barrier, NUCLEAR physics, NEUTRINO interactions, SUPERNOVAE, ISOBARIC spin
Abstract

Gamow-Teller (GT) transitions starting from stable as well as unstable pf-shell nuclei are of interest not only in nuclear physics, but also in astrophysics, e.g. in violent neutrino-induced reactions at the core-collapse stage of type II supernovae. In the β-decay study of these pf-shell nuclei, half-lives can be measured rather accurately. On the other hand, in high-resolution (3He,t) charge-exchange reactions at 0°, individual GT transitions up to high excitations can be studied. Assuming the isospin symmetry for the strengths of Tz = ±1→0 analogous GT transitions, we present a unique “merged analysis” for the determination of absolute B(GT) values. This method can be applied not only to T = 1 systems, but also to higher T systems. [ABSTRACT FROM AUTHOR]

Published
2008
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17. Nuclear Structure and Reaction Mechanism Studies with Multinucleon Reactions.

Author

Regan, P. H., Jones, G. A., Podolyák, Zs., de Angelis, G., Zhang, Y. H., Gadea, A., Ur, C. A., Abdullah, M., Axiotis, M., Bazzacco, D., Broda, R., Bucurescu, D., Farnea, E., Gelletly, W., Ionescu-Bujor, M., Iordachescu, A., Kröll, Th., Langdown, S. D., Lenzi, S., and Lunardi, S.

Subjects
NUCLEAR structure, SELENIUM, OSMIUM, HEAVY ions, ANGULAR momentum (Nuclear physics), NUCLEAR physics
Abstract

This contribution reports on the results of an experiment to study the near-yrast states in selenium- and osmium-like nuclei, following their population in thick-target, multinucleon transfer reactions between an 82Se beam and a 192Os target. The experimental results for the level scheme for 84Se are presented together with investigations into the use of multi-dimensional gamma-ray energy gating to investigate angular momentum population in such heavy-ion binary reactions. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2006
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18. Studies of the Single Particle Structure of Exotic Nuclei using Transfer Reactions.

Author

Fernández-Domínguez, B., Lemmon, R. C., Timis, C., Labiche, M., Catford, W. N., Chartier, M., Ashwood, N., Amzal, N., Baldwin, T. D., Burns, M., Caballero, L., Chapman, R., Curtis, N., de France, G., Freer, M., Gelletly, W., Liang, X., Orr, N. A., Pain, S. D., and Pucknell, V. P. E.

Subjects
NUCLEAR physics, NUCLEAR energy, NUCLEAR reactions, PHYSICS, PARTICLES (Nuclear physics)
Abstract

The TIARA+VAMOS+EXOGAM set-up has recently been installed at GANIL to study the single-particle structure of exotic nuclei. The unique characteristics of the TIARA array, combined with the large acceptance spectrometer VAMOS and the high efficiency Germanium detector array EXOGAM, has allowed high-resolution measurements of transfer reactions in inverse kinematics using low intensity exotic beams. We will describe the experimental set-up, data analysis and preliminary results of the first experiments using a 24Ne beam from SPIRAL, concentrating in particular on the performance of VAMOS that has been used to detect the heavy fragments after the (d,p), (d,d) and (d,t) reactions. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2006
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19. RARE ISOTOPES INVESTIGATIONS AT GSI (RISING) USING RELATIVISTIC ION BEAMS.

Author

JOLIE, J., ILIE, G., REITER, P., RICHARD, A., SCHERILLO, A., STRIEPLING, T., WARR, N., MALLION, S., NEYENS, G., TURZO, K., VAN DUPPEN, P., VERMEULEN, N., PODOLYAK, ZS., GELLETLY, W., REGAN, P. H., WALKER, P. M., CATFORD, W. N., LIU, Z., WILLIAMS, S., and BLAZHEV, A.

Subjects
ION beams, STABLE isotopes, EXOTIC nuclei, ATOMIC nucleus, NUCLEAR physics
Published
2006

20. Structural Evolution in the (N,Z,Iπ) Coordinate Frame for A∼100.

Author

Regan, P. H., Wheldon, C., Yamamoto, A. D., Wu, C. Y., Ashley, S., Mumby-Croft, P., Seaborne, D., Macchiavelli, A. O., Cline, D., Smith, J. F., Chakrawarthy, R. S., Cromaz, M., Fallon, P., Freeman, S. J., Gelletly, W., Görgen, A., Hayes, A., Hua, H., Langdown, S. D., and Lee, I. Y.

Subjects
NUCLEON-nucleon interactions, ANGULAR momentum (Mechanics), DEFORMATIONS (Mechanics), NUCLEAR structure, KINEMATICS, NUCLEAR physics
Abstract

Multinucleon transfer reactions between a thin 100Mo target and a 136Xe beam at an energy of 700 MeV have been used to investigate the evolution of structure with increasing angular momentum in a range of nuclei with A∼100. The use of kinematically complete experiments coupled with isomer tagging allow the selection of specific exit channels. The evolution from quasi-vibrational states at low spins to quasi-rotational structures following the population of a low-Ω, ‘rotationally aligned’ h11/2 neutron configuration is demonstrated to be a standard feature of the region using the so-called E-Gamma Over Spin (E-GOS) empirical prescription. This treatment is extended to odd-A nuclei. [ABSTRACT FROM AUTHOR]

Published
2004
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21. NUCLEAR WEAK RESPONSE FROM THE COMBINED STUDY OF β-DECAY AND CHARGE-EXCHANGE REACTION.

Author

FUJITA, Y., RUBIO, B., GELLETLY, W., BLANK, B., ADACHI, T., ALGORA, A., ASCHER, P., CAKIRLI, R.B., DE FRANCE, G., GIOVINAZZO, J., GRÉVY, S., FUJITA, H., KUCUK, L., MARQUÉS, M., MOLINA, F., OKTEM, Y., DE OLIVEIRA SANTOS, F., PERROT, L., RAABE, R., and SRIVASTAVA, P.C.

Subjects
NUCLEAR physics, CHARGE exchange, HALF-life (Nuclear physics), RADIOACTIVE decay, ISOBARIC spin
Abstract

Studying the weak nuclear response, especially the Gamow-Teller (GT) transitions, of stable as well as unstable pf-shell nuclei, is one of the key issues in nuclear and astro-nuclear physics. We study the decay half-lives and the GT transitions starting from Tz = ±1 and ±2 mirror nuclei, respectively, by means of β decays and complementary hadronic (3He, t) charge-exchange reactions. Under the assumption that isospin is a good quantum number, symmetry is expected for mirror nuclei and the GT transitions starting from the mirror nuclei. The half-lives and branching ratios and the measured strength distributions of GT transitions are compared and also combined for the understanding of the nuclear structure of pf-shell nuclei far-from-stability. [ABSTRACT FROM AUTHOR]

Published
2009
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22. ISOMERIC RATIOS FOR NUCLEI WITH Z = 62-67 AND A = 142-152 PRODUCED IN THE RELATIVISTIC FRAGMENTATION OF 208Pb.

Author

MYALSKI, S., MAJ, A., PODOLYÁK, Zs., BECKER, F., BEDNARCZYK, P., BENZONI, G., BLANK, B., BRANDAU, C., BRUCE, A. M., CÁCERES, L., CAMERA, F., CATFORD, W. N., CULLEN, I. J., DOMBRADI, ZS., DOORNENBAL, P., ESTEVEZ, E., GARNSWORTHY, A. B., GEISSEL, H., GELLETLY, W., and GERL, J.

Subjects
NUCLEAR isomers, NUCLEAR physics, NUCLEAR fragmentation, LEAD, NUCLIDES
Abstract

Isomeric states in nuclei with Z = 62-67 and A = 142-152 produced in the fragmentation of the relativistic (1 GeV/nucleon) 208Pb beam were investigated. Isomeric ratios were determined for 10 isomeric states. Significant differences between theoretical and experimental values were observed. [ABSTRACT FROM AUTHOR]

Published
2009

23. STRUCTURE OF NEUTRON–RICH NUCLEI FROM DEEP–INELASTIC REACTIONS.

Author

Podolyak, Zs., Mohammadi, S., de Angelis, G., Zhang, Y. H., Axiotis, M., Bazzacco, D., Bizzeti, P. G., Brandolini, F., Broda, R., Bucurescu, D., Farnea, E., Gelletly, W., Gadea, A., Ionescu-Bujor, M., Iordachescu, A., Kroll, Th., Langdown, S. D., Lunardi, S., and Marginean, N.

Subjects
NEUTRONS, NUCLEAR reactions, NUCLEAR physics
Abstract

Neutron rich nuclei have been populated using the [sup 82]Se+[sup 192]Os deep-inelastic reaction. New experimental results on [sup 188]W, [sup 188,190]Os target-like nuclei, as well as [sup 74,76,78]Ge beam-like nuclei are presented. [ABSTRACT FROM AUTHOR]

Published
2004

24. Science with radioactive beams: the alchemist's dream.

Author

Gelletly, W.

Subjects
*RADIOACTIVE nuclear beams, *NUCLEAR physics
Abstract

Nuclear science is being transformed by a new capacity to create beams of radioactive nuclei. Until now all of our knowledge of nuclear physics and the applications which flow from it has been derived from studies of radioactive decay and nuclear reactions induced by beams of the 283 stable or long-lived nuclear species we can find on Earth. Here we describe first how beams of radioactive nuclei can be created. The present status of nuclear physics is then reviewed before potential applications to nuclear physics, nuclear astrophysics, materials science, bio-medical, and environmental studies are described. [ABSTRACT FROM AUTHOR]

Published
2001
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25. Tz = ±1 → 0 ISOSPIN SYMMETRY GAMOW-TELLER TRANSITIONS IN pf-SHELL NUCLEI.

Author

FUJITA, Y., ADACHI, T., FUJITA, H., SHIMBARA, Y., RUBIO, B., GELLETLY, W., and MOLINA, F.

Subjects
PROTONS, NUCLEAR physics, NEUTRONS, SYMMETRY (Physics), ASTROPHYSICS
Abstract

Studying the Gamow-Teller (GT) transitions of stable as well as unstable pf-shell nuclei is one of the key issues in nuclear and astro-nuclear physics. Under the assumption that isospin T is a good quantum number, symmetry is expected for mirror nuclei and the GT transitions starting from the mirror nuclei. We study the GT transitions starting from Tz = ±1 mirror nuclei, respectively, by means of hadronic (3He, t) charge-exchange reactions and complementary β decays. [ABSTRACT FROM AUTHOR]

Published
2010
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26. The decay of neutron-deficient Lu isotopes

Author

Rastikerdar, S, Garrett, C, and Gelletly, W

Subjects
Nuclear Physics
Abstract

Neutron-deficient isotopes of Lu with masses 158, and 160-5 have been produced in /sup 155/Gd(/sup 14/N, xn) and /sup 151/Eu(/sup 16/O, xn) reactions with beams of /sup 14/N and /sup 16/O from the Manchester HILAC. Gamma ray energies and relative intensities have been measured as well as X- gamma , gamma - gamma and beta /sup +/- gamma coincidences. The half-lives and decay energies for beta /sup +//EC decay have been measured. Gamma-gamma correlations and conversion electron single spectra are studied in the case of the even isotopes. Preliminary results are reported. (13 refs).

Published
1981

28. Total Absorption Study of Beta Decays Relevant for Nuclear Applications and Nuclear Structure.

Author

Algora, A., Valencia, E., Taín, J. L., Jordan, M. D., Agramunt, J., Rubio, B., Estevez, E., Molina, F., Montaner, A., Guadilla, V., Fallot, M., Porta, A., Zakari-Issoufou, A.-A., Bui, V. M., Rice, S., Podolyák, Zs., Regan, P. H., Gelletly, W., Bowry, M., and Mason, P.

Subjects
*NUCLEAR structure, *BETA decay, *BROMINE isotopes, *ABSORPTION spectra, *NUCLEAR physics, *NEUTRONS
Abstract

An overview is given of our activities related to the study of the beta decay of neutron rich nuclei relevant for nuclear applications. Recent results of the study of the beta decay of 87,88Br using a new segmented total absorption spectrometer are presented. The measurements were performed at the IGISOL facility using trap-assisted total absorption spectroscopy. [ABSTRACT FROM AUTHOR]

Published
2014
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30. Complete spectroscopy of the 162Dy nucleus

Author

Aprahamian, A., Wu, X., Lesher, S.R., Warner, D.D., Gelletly, W., Börner, H.G., Hoyler, F., Schreckenbach, K., Casten, R.F., Shi, Z.R., Kusnezov, D., Ibrahim, M., Macchiavelli, A.O., Brinkman, M.A., and Becker, J.A.

Subjects
*NUCLEAR physics, *COLLISIONS (Nuclear physics), *ENGINEERING instruments, *PHYSICS instruments
Abstract

Abstract: States in 162Dy have been populated by , , and reactions in order to characterize a complete set of low K bands below 2 MeV. The and measurements were made using high precision curved crystal and spectrometers. Gamma–gamma coincidence and DCO measurements were made following the reaction using an array of Compton-suppressed Ge detectors. Using all these data and employing the Ritz combination principle, a level scheme was developed which represents one of the most complete and extensive spectra of levels available for comparison with nuclear models. The observed positive and negative parity bands are discussed in terms of collective quadrupole and octupole vibrational excitations as well as 2 quasi-particle excitations. [Copyright &y& Elsevier]

Published
2006
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31. Single particle structure of exotic nuclei with transfer reactions

Author

Fernández-Domínguez, B., Lemmon, R.C., Timis, C., Labiche, M., Catford, W.N., Chartier, M., Ashwood, N.I., Amzal, N., Baldwin, T.D., Burns, M., Caballero, L., Chapman, R., Curtis, N., de France, G., Freer, M., Gelletly, W., Liang, X., Orr, N.A., Pain, S.D., and Pucknell, V.P.E.

Subjects
*NUCLEAR physics, *EXOTIC nuclei, *NUCLEAR energy, *PHYSICAL sciences
Abstract

Abstract: We report here on the first results obtained from the study of the 24Ne(d, p)25Ne reaction performed with SPIRAL beam at GANIL using the new TIARA+V AMOS+EXOGAM setup. [Copyright &y& Elsevier]

Published
2007
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32. Spallation-reaction cross sections relevant for accelerator-driven systems

Author

J. Benlliure, J. Taieb, C. Stephan, M. Bernas, W. Wlazlo, R. Legrain, S. Leray, L. Tassan-Got, K.-H. Schmidt, S. Czajkowski, F. Farget, M.S. Pravikoff, P. Armbruster, A. Boudard, E. Casarejos, C. Volant, B. Mustapha, T. Enqvist, Institut de Physique Nucléaire d'Orsay (IPNO), 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), and Rubio B. Lozano M. Gelletly W.

Subjects
Physics, Internet, scholar, research, Spectrometer, 020206 networking & telecommunications, cyber, 02 engineering and technology, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Residual, Mass spectrometry, 7. Clean energy, Nuclear physics, Uranium-238, Deuterium, 0202 electrical engineering, electronic engineering, information engineering, Mass spectrum, method, scientific, 020201 artificial intelligence & image processing, Spallation, Nuclide, science
Abstract

This contribution reports on the cross section measurements performed at GSI on the isotopic distribution of the residual nuclides of spallation reactions in inverse kinematics. The fragment separator (FRS) was used to select and identify the reaction products, and the full (Z,N) map was measured above the production limit of 0.1 mb. The high resolution of the spectrometer allowed to determine the velocity distributions of all products. These data are relevant for the design of accelerator-driven subcritical reactors. They are also of the highest importance to improve the understanding of the spallation mechanism.

Published
1999

33. Spallation reactions: a tool for RNB production and a neutron source for nuclear waste transmutation

Author

C. Volant, M. Bernas, T. Enqvist, C. Stephan, R. Legrain, S. Czajkowski, F. Farget, J. Benlliure, L. Tassan-Got, J. Taieb, M.S. Pravikoff, A. Boudard, P. Armbruster, K.-H. Schmidt, E. Casarejos, S. Leray, Institut de Physique Nucléaire d'Orsay (IPNO), 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), Rubio B. Lozano M. Gelletly W., and Robert, Suzanne

Subjects
Radioactive ion beams, problem formulation, maxims of conversation, Nuclear transmutation, Chemistry, [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], Radioactive waste, 020206 networking & telecommunications, 02 engineering and technology, problem modeling, problem expression, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], problem understanding, Nuclear physics, Recoil, 0202 electrical engineering, electronic engineering, information engineering, Physics::Accelerator Physics, Neutron source, 020201 artificial intelligence & image processing, Spallation, competitive intelligence, information retrieval, Nuclear Experiment, pragmatics
Abstract

If simplified, every information retrieval problem can be solved when the information need implied by its expression has been identified. We are interested in the criteria used in realising a good information retrieval problem expression. We have listed these criteria through some principles and maxims which first characterized the communication between two persons are applied. We choose to use the gricean maxims because they are the most favoured for this type of situation. Secondly, we have tried to identify some others principles that can be used to realise a good information retrieval problem expression. The principles by Grice can not resolve all forms of error associated with this particular form of communication. In our work, we defined three other principles namely: adhesion principle, reformulation principle, memorization principle. We give some examples of situations where the principles we have formulated are not applicable and the consequences. We present the possible applications of our new model: MIRABEL, which can help in the description of information retrieval problem from. It also compels its user to use essential good expression principle implicitly.

Published
1999

34. Beta decay asymmetry in mirror nuclei: A=9

Author

Y. Jading, U. C. Bergmann, Gunnar Nyman, Karin Markenroth, K. Wilhelmsen Rolander, H. O. U. Fynbo, Ismael Martel, F. Wenander, Leif Axelsson, K. Riisager, Olof Tengblad, Thomas Nilsson, I. G. Mukha, P. Hornshøj, L. M. Fraile, Björn Jonson, M. J. G. Borge, Rubio, B., Lozano, M., and Gelletly, W.

Subjects
Physics, media_common.quotation_subject, Nuclear Theory, Nuclear structure, Beta decay, Asymmetry, Nuclear physics, Beta (plasma physics), Halo, Mirror nuclei, Nuclear drip line, Nuclear Experiment, Radioactive decay, media_common
Abstract

Investigations of light nuclei close to the drip lines have revealed new and intriguing features of the nuclear structure. The occurrence of halo structures in loosely bound systems has had a great impact on the nuclear physics research in the last years, as intriguing, but not yet solved, is the nature of transitions with very large beta strength. We report here on the investigation of this latter feature by an accurate measurement of the beta decay asymmetry between the mirror nuclei in the A=9 mass chain.

Published
1999

35. Radioactive ion beams at ISOLDE/CERN recent developments and perspectives

Author

U. Georg, O. C. Jonsson, Richard Catherall, V. N. Fedoseyev, J. R. J. Bennett, P. V. Drumm, H. Ravn, Jacques Lettry, C. Tamburella, U. Köster, V. I. Mishin, A. R. Junghans, E. Kugler, T. Giles, H. Simon, U. C. Bergmann, K.-H. Schmidt, T. Nilsson, Rubio, B., Lozano, M., and Gelletly, W.

Subjects
Physics, Large Hadron Collider, Proton, Particle accelerator, Proton Synchrotron Booster, law.invention, Nuclear physics, Synchrocyclotron, law, Ionization, Physics::Accelerator Physics, Spallation, Nuclear Experiment, Beam (structure)
Abstract

Since the move of ISOLDE from CERN’s synchrocyclotron (SC) to the Proton Synchrotron Booster (PSB) in 1992 extensive work has been devoted to the development of new beams, i.e. the production of new isotopes, beams of higher intensity and the ionization of further elements. Most of these developments were driven by the particular needs of the physics community proposing new experiments. The main achievements were the adaption of liquid metal targets to the pulsed proton beam to prevent shockwaves and splashing inside the target container and systematic studies on the time structure of the release of the isotopes from the target. Furthermore the work on laser ion-sources already started at ISOLDE-2 was continued, the so-called RIST target was developed, and most recently first tests on the isotope production while increasing the proton energy from 1 GeV to 1.4 GeV were done. The latter topics are discussed in this paper.

Published
1999
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36. Isospin and spin-isospin modes in charge-exchange reactions

Author

M. Fujiwara, Sijtze Brandenburg, R. G. T. Zegers, Mohsen Harakeh, A. Willis, Hidetoshi Akimune, H. Laurent, van den Ad M Berg, KVI - Center for Advanced Radiation Technology, Damage and Repair in Cancer Development and Cancer Treatment (DARE), Institut de Physique Nucléaire d'Orsay (IPNO), 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), Rubio B. Lozano M. Gelletly W., and Robert, Suzanne

Subjects
Physics, Isovector, [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], 010308 nuclear & particles physics, Branching fraction, 020209 energy, High Energy Physics::Lattice, Nuclear Theory, Magnetic monopole, 02 engineering and technology, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Nuclear physics, Isospin, Giant resonance, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Spin-flip, Proton emission, Atomic physics, Random phase approximation, Nuclear Experiment
Abstract

The microscopic structure of the Gamow-Teller resonance (GTR) and spin-dipole resonance (SDR) in 208Bi has been investigated in the 208Pb(3He,tp)207Pb reaction at E(3He)=450 MeV and very forward scattering angles. The partial and total branching ratios and the escape widths for GTR and SDR decay to the residual neutron-hole states in 207Pb were deduced. These are found to be in good agreement with recent theoretical estimates. The (3He,tp) reaction on Pb at E(3He)=177 MeV was also studied in order to locate isovector monopole strength corresponding to 2ℏω transitions. Monopole strength at excitation energies above 25 MeV was discovered and compared to calculated strength due to the isovector giant monopole resonance and the spin-flip isovector monopole resonance. Calculations in a normal-mode framework show that all isovector monopole strength can be accounted for if the branching ratio for decay by proton emission is 20%.

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