Search

Your search keyword '"M. Djongolov"' showing total 44 results
Start Over Author "M. Djongolov"
44 results on '"M. Djongolov"'

1. Shell evolution approaching the N=20 island of inversion: Structure of 26Na

Author

G.L. Wilson, W.N. Catford, N.A. Orr, C.Aa. Diget, A. Matta, G. Hackman, S.J. Williams, I.C. Celik, N.L. Achouri, H. Al Falou, R. Ashley, R.A.E. Austin, G.C. Ball, J.C. Blackmon, A.J. Boston, H.C. Boston, S.M. Brown, D.S. Cross, M. Djongolov, T.E. Drake, U. Hager, S.P. Fox, B.R. Fulton, N. Galinski, A.B. Garnsworthy, D. Jamieson, R. Kanungo, K.G. Leach, J.N. Orce, C.J. Pearson, M. Porter-Peden, F. Sarazin, E.C. Simpson, S. Sjue, D. Smalley, C. Sumithrarachchi, S. Triambak, C. Unsworth, and R. Wadsworth

Subjects
81V35, Nuclear structure, 26Na, γ-Ray transitions, Transfer reactions, Shell migration, Physics, QC1-999
Abstract

The levels in 26Na with single particle character have been observed for the first time using the d(25Na, pγ) reaction at 5 MeV/nucleon. The measured excitation energies and the deduced spectroscopic factors are in good overall agreement with (0+1)ħω shell model calculations performed in a complete spsdfp basis and incorporating a reduction in the N=20 gap. Notably, the 1p3/2 neutron configuration was found to play an enhanced role in the structure of the low-lying negative parity states in 26Na, compared to the isotone 28Al. Thus, the lowering of the 1p3/2 orbital relative to the 0f7/2 occurring in the neighbouring Z=10 and 12 nuclei – 25,27Ne and 27,29Mg – is seen also to occur at Z=11 and further strengthens the constraints on the modelling of the transition into the island of inversion.

Published
2016
Full Text
View/download PDF

2. Microscopic structure of the one-phonon 2+ states of Po208

Author

G. De Gregorio, K. A. Gladnishki, C. Müller-Gatermann, Marcus Scheck, K. E. Ide, Norbert Pietralla, H. Naïdja, K. Stoychev, S. S. Dimitrova, V. Werner, R. Kern, A. Dewald, C. Henrich, A. Gargano, Th. Kröll, M. Stoyanova, D. Kalaydjieva, P. R. John, I. Homm, D. Kocheva, J. Jolie, A. Blazhev, V. Karayonchev, M. Djongolov, P. Spagnoletti, J. Kleemann, A. Esmaylzadeh, A. Goldkuhle, G. Rainovski, A. Yaneva, M. Beckers, and C. Fransen

Subjects
Physics, Matrix (mathematics), symbols.namesake, Recoil, Isovector, Phonon, Nuclear Theory, Quadrupole, symbols, Spectroscopy, Valence electron, Doppler effect, Molecular physics
Abstract

The lifetimes of the 2 1 + and 4 1 + states of Po 208 were measured in the α -transfer reaction Pb 204 ( C 12 , Be 8 ) Po 208 by γ -ray spectroscopy utilizing the recoil distance Doppler shift method. The newly extracted transition strengths alongside ones of the decay of the 2 2 + state were compared to the results of large-scale shell-model calculations using an effective interaction derived from the realistic CD-Bonn nucleon-nucleon potential. The comparison indicates the importance of the quadrupole isovector excitations in the valence shell for a fine tuning of the two-body matrix elements of the shell-model interaction.

Published
2021
Full Text
View/download PDF

3. Lifetimes and structures of low-lying negative-parity states of Po-209

Author

M. Stoyanova, A. Esmaylzadeh, J.-M. Régis, L. Knafla, G. Rainovski, D. Kocheva, A. Blazhev, G. De Gregorio, V. Karayonchev, M. Djongolov, K. A. Gladnishki, L. Kornwebel, C. Fransen, J. Jolie, A. Gargano, Karayonchev, V, Stoyanova, M, Rainovski, G, Jolie, J, Blazhev, A, Djongolov, M, Esmaylzadeh, A, Fransen, C, Gladnishki, K, Knafla, L, Kocheva, D, Kornwebel, L, Regis, Jm, De Gregorio, G, and Gargano, A

Subjects
Physics, Yrast, Order (ring theory), Neutron, Parity (physics), State (functional analysis), Atomic physics, Wave function, Coupling (probability)
Abstract

The $5/{2}_{1}^{\ensuremath{-}}$, $9/{2}_{1}^{\ensuremath{-}}$, and $11/{2}_{1}^{\ensuremath{-}}$ states in $^{209}\mathrm{Po}$ were populated in the $\ensuremath{\beta}$ decay of $^{209}\mathrm{At}$ and their lifetimes measured using the electronic $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ fast timing technique. The lifetime of the $9/{2}_{1}^{\ensuremath{-}}$ state is measured for first time. The lifetime of the $5/{2}_{1}^{\ensuremath{-}}$ is measured to be shorter than the value adopted in the literature while the lifetime of the $11/{2}_{1}^{\ensuremath{-}}$ state agrees well with the previous measurement. In order to get deeper insight into the structure of the states, a shell-model calculation was carried out adopting a microscopic effective interaction derived from the realistic CD-Bonn potential. The comparison between theoretical and experimental data for the low-lying negative-parity states of $^{209}\mathrm{Po}$ supports the reliability of the predicted wave functions, which are found to be dominated by the coupling of a neutron hole to the yrast states of $^{210}\mathrm{Po}$. However, it also points to the important role played by minor wave-function components in describing the reduced electromagnetic strengths, suggesting the need of additional configuration mixing for achieving a better quantitative agreement.

Published
2021

4. Experimental evidence for low-lying quadrupole isovector excitation of $$^{208}$$Po

Author

P. R. John, J. Jolie, P. Spagnoletti, K. A. Gladnishki, G. Rainovski, C. Fransen, A. Dewald, Th. Kröll, D. Kalaydjieva, A. Blazhev, Marcus Scheck, A. Yaneva, K. E. Ide, R. Kern, C. Henrich, J. Kleemann, D. Kocheva, I. Homm, Norbert Pietralla, V. Werner, M. Stoyanova, C. Müller-Gatermann, V. Karayonchev, and M. Djongolov

Subjects
Physics, Nuclear and High Energy Physics, Isovector, 010308 nuclear & particles physics, 0103 physical sciences, Hadron, Quadrupole, Nuclear fusion, State (functional analysis), Atomic physics, 010306 general physics, 01 natural sciences, Excitation
Abstract

We present the results from an experiment dedicated to measure the lifetime of the $$2^+_2$$ state, candidate for the one-phonon mixed-symmetry state, of $$^{208}$$ Po. This nucleus was studied in the $$\alpha $$ -transfer reaction $$^{204}$$ Pb( $$^{12}$$ C, $$^{8}$$ Be) $$^{208}$$ Po and the lifetime of the $$2^+_2$$ state was determined by utilizing the Doppler-shift attenuation method. The experimental data show that the $$2^+_2$$ state decays with a sizable M1 transition to the $$2^+_1$$ state revealing its isovector nature.

Published
2020
Full Text
View/download PDF

5. Coulomb Excitation of Proton-rich N=80 Isotones at HIE-ISOLDE

Author

D. Kocheva, E. Giannopoulos, Hilde De Witte, J. Jolie, O. Möller, Marcus Scheck, J. Snäll, S. Thiel, Herbert Hess, A. Welker, P. A. Söderström, J. M. Keatings, K. A. Gladnishki, J. G. Cubiss, Norbert Pietralla, R. Stegmann, G. Rainovski, Janne Pakarinen, Liam Gaffney, A. Vogt, A. Blazhev, V. Werner, C. Fransen, R. Kern, Joakim Cederkäll, G. G. O'Neill, L. Kaya, D. Rosiak, T. Kröll, P. Reiter, M. Stoyanova, P. Spagnoletti, J. Wiederhold, V. Karayonchev, M. Djongolov, Radostina Zidarova, N. Warr, and Amar Boukhari

Subjects
History, Ion beam, Proton, Silicon, Physics::Instrumentation and Detectors, chemistry.chemical_element, Coulomb excitation, hiukkasfysiikka, 01 natural sciences, Education, Ion, Nuclear physics, 0103 physical sciences, Nuclear Physics - Experiment, 010306 general physics, Nuclear Experiment, Physics, Large Hadron Collider, 010308 nuclear & particles physics, Projectile, Charged particle, Computer Science Applications, chemistry, Physics::Accelerator Physics, ydinfysiikka
Abstract

A projectile Coulomb-excitation experiment was performed at the radioactive ion beam facility HIE-ISOLDE at CERN. The radioactive 140Nd and 142Sm ions were post accelerated to the energy of 4.62 MeV/A and impinged on a 1.45 mg/cm2-thin 208Pb target. The γ rays depopulating the Coulomb-excited states were recorded by the HPGe-array MINIBALL. The scattered charged particles were detected by a double-sided silicon strip detector in forward direction. Experimental γ-ray intensities were used for the determination of electromagnetic transition matrix elements. Preliminary results for the reduced transition strength of the B ( M 1 ; 2 3 + → 2 1 + ) = 0.35 ( 19 ) μ N 2 of 140Nd and a first estimation for 142Sm have been deduced using the Coulomb-excitation calculation software GOSIA. The 2 3 + states of 140Nd and 142Sm show indications of being the main fragment of the proton-neutron mixed-symmetry 2 1 , ms + state.

Published
2020

6. Precise branching ratio measurements in Ne19β decay and fundamental tests of the weak interaction

Author

S. O’Hagan, S. Sjue, M. Djongolov, Rae Austin, H. Al-Falou, C. Kierans, A. B. Garnsworthy, R. D’Entremont, B. Rebeiro, M. R. Pearson, L. Milovanovic, R. Churchman, R. Kshetri, R. Dunlop, E. R. Tardiff, S. S. Ntshangase, D. S. Cross, C. E. Svensson, G. Hackman, S. J. Williams, S. Triambak, G. C. Ball, Chandana Sumithrarachchi, J. N. Orce, S. Reeve, P. Z. Mabika, P. E. Garrett, and P. Finlay

Subjects
Semileptonic decay, Physics, Ion beam, Spectrometer, 010308 nuclear & particles physics, Branching fraction, Weak interaction, 01 natural sciences, Beta decay, Nuclear physics, Excited state, 0103 physical sciences, 010306 general physics, Ground state
Abstract

We used the 8$\pi$ $\gamma$-ray spectrometer at the TRIUMF-ISAC radiocative ion beam facility to obtain high-precision branching ratios for $^{19}$Ne $\beta^+$ decay to excited states in $^{19}$F. Together with other previous work, our measurements determine the superallowed $1/2^+ \to 1/2^+$ beta branch to the ground state in $^{19}$F to be 99.9878(7)\%, which is three times more precise than known previously. The implications of these measurements for testing a variety of weak interaction symmetries are discussed briefly.

Published
2019
Full Text
View/download PDF

7. Evolution of the structure of the ${4}_{1}^{+}$ states in Po isotopes

Author

M. Stoyanova, A. Dewald, A. Yaneva, C. Müller-Gatermann, V. Karayonchev, C. Fransen, M. Djongolov, R. Kern, J. Garbe, P. R. John, J. Kleemann, L. M. Gerhard, K. E. Ide, G. Rainovski, K. A. Gladnishki, J.-M. Régis, A. Blazhev, Norbert Pietralla, P. Spagnoletti, Th. Kröll, V. Werner, A. Esmaylzadeh, J. Jolie, and D. Kocheva

Subjects
Physics, Nuclear physics, History, Tandem, Scope (project management), chemistry, Isotope, Yrast, chemistry.chemical_element, Computer Science Applications, Education, Polonium
Abstract

The lifetime of the state in 208Po has been measured using γ − γ fast-timing technique with LaBr3(Ce) Detectors. The experiment was performed at the FN Tandem facility at the University of Cologne. The preliminary results are discussed in the scope of the systematic behavior of the transition strengths between yrast states in polonium isotopes.

Published
2020
Full Text
View/download PDF

8. Lifetime measurements of the low-lying excited states of 208Po

Author

K. E. Ide, L. M. Gerhard, B. Falk, C. Henrich, Th. Kröll, J. Garbe, K. A. Gladnishki, A. Dewald, R. Kern, L. Knafla, A. Blazhev, C. Fransen, M. Beckers, G. Hackenberg, M. Ley, F. Dunkel, M. Cappellazzo, V. Werner, F. Diel, I. Homm, A. Esmaylzadeh, T. Schmidt, Norbert Pietralla, L. Bussmann, R.-B. Gerst, P. Spagnoletti, L. Kornwebel, J. Jolie, A. Yaneva, D. Kocheva, M. Stoyanova, A. Goldkuhle, G. Rainovski, V. Karayonchev, M. Djongolov, Marcus Scheck, J. Kleeman, D. Kalaydjieva, and C. Müller-Gatermann

Subjects
Physics, History, Excited state, Atomic physics, Lying, Computer Science Applications, Education
Abstract

In this study we present the preliminary results about the lifetimes of the 2 2 + , 4 1 + states of 208Po and the upper limit of the lifetime of the 2 1 + state. For measuring the lifetimes of the 2 1 + and 4 1 + states the Recoil Distance Doppler Shift (RDDS) method and for the lifetime of the 2 2 + state the Doppler Shift Attenuation method (DSAM) were used. The resulting absolute transition strength B ( M 1 ; 2 2 + → 2 1 + ) ≥ 0.122 ( 20 ) μ N 2 reveals the predominant isovector nature of the 2 2 + state of 208Po.

Published
2020
Full Text
View/download PDF

9. Reorientation-effect measurement of the first 2+ state in 12C : Confirmation of oblate deformation

Author

Chandana Sumithrarachchi, H. Al Falou, J. Wong, D.L. Mavela, E. T. Rand, T.E. Drake, C. E. Svensson, S. J. Williams, N. Erasmus, C. Ngwetsheni, S. Sjue, M. Kumar Raju, D.S. Cross, A. B. Garnsworthy, C. J. Pearson, S. Masango, J. N. Orce, K. Abrahams, P. E. Garrett, M. Djongolov, G. G. O'Neill, E. R. Tardiff, E.H. Akakpo, M.J. Mokgolobotho, S. Triambak, C. Mehl, P. Finlay, Ritesh Kshetri, G. C. Ball, D. G. Jenkins, K. G. Leach, G. Hackman, R. Churchman, and Petr Navrátil

Subjects
Physics, Nuclear and High Energy Physics, Spectrometer, Nuclear Theory, 010308 nuclear & particles physics, FOS: Physical sciences, State (functional analysis), 01 natural sciences, Coincidence, lcsh:QC1-999, Nuclear Theory (nucl-th), Ab initio quantum chemistry methods, Polarizability, Excited state, 0103 physical sciences, Quadrupole, Atomic physics, Nuclear Experiment (nucl-ex), 010306 general physics, Ground state, Nuclear Experiment, lcsh:Physics
Abstract

A Coulomb-excitation reorientation-effect measurement using the TIGRESS γ−ray spectrometer at the TRIUMF/ISAC II facility has permitted the determination of the 〈 2 1 + ‖ E 2 ˆ ‖ 2 1 + 〉 diagonal matrix element in 12C from particle−γ coincidence data and state-of-the-art no-core shell model calculations of the nuclear polarizability. The nuclear polarizability for the ground and first-excited (2 1 + ) states in 12C have been calculated using chiral NN N4LO500 and NN+3NF350 interactions, which show convergence and agreement with photo-absorption cross-section data. Predictions show a change in the nuclear polarizability with a substantial increase between the ground state and first excited 2 1 + state at 4.439 MeV. The polarizability of the 2 1 + state is introduced into the current and previous Coulomb-excitation reorientation-effect analyses of 12C. Spectroscopic quadrupole moments of Q S ( 2 1 + ) = + 0.053 ( 44 ) eb and Q S ( 2 1 + ) = + 0.08 ( 3 ) eb are determined, respectively, yielding a weighted average of Q S ( 2 1 + ) = + 0.071 ( 25 ) eb, in agreement with recent ab initio calculations. The present measurement confirms that the 2 1 + state of 12C is oblate and emphasizes the important role played by the nuclear polarizability in Coulomb-excitation studies of light nuclei.

Published
2018

10. Search for Isovector Valence-Shell Excitations in 140 Nd and 142 Sm via Coulomb excitation reactions of radioactive ion beams

Author

Herbert Hess, P. Reiter, J. Jolie, J. Wiederhold, A. Blazhev, K. A. Gladnishki, Radostina Zidarova, E. Giannopoulos, D. Kocheva, P. A. Söderström, N. Warr, T. Kröll, M. Stoyanova, J. M. Keatings, Amar Boukhari, P. Spagnoletti, V. Werner, G. G. O'Neill, V. Karayonchev, A. Vogt, M. Djongolov, D. Rosiak, S. Thiel, G. Rainovski, Liam Gaffney, Norbert Pietralla, C. Fransen, L. Kaya, R. Kern, A. Welker, J. Snäll, Janne Pakarinen, J. G. Cubiss, R. Stegmann, Hilde De Witte, O. Möller, Joakim Cederkäll, Marcus Scheck, Arsenyev, N, Bezbakh, A, Rogov, I, Shneidman, T, Vdovin, A, Arsenyev, N., Bezbakh, A., Rogov, I., Shneidman, T., and Vdovin, A.

Subjects
Silicon, Physics::Instrumentation and Detectors, QC1-999, chemistry.chemical_element, Coulomb excitation, 01 natural sciences, Ion, 0103 physical sciences, Nuclear Physics - Experiment, Nuclear Experiment, 010306 general physics, Coulomb excitation experiments, Physics, Large Hadron Collider, Isovector, ta114, 010308 nuclear & particles physics, Projectile, Detector, chemistry, Physics::Accelerator Physics, Atomic physics, Valence electron, ydinfysiikka
Abstract

Projectile Coulomb excitation experiments were performed at HIE-ISOLDE at CERN with the radioactive ion beams of 140Nd and 142Sm. Ions with an energy of 4:62 MeV/A were impinging on a 1.45 mg/cm2 thick 208Pb target. The γ-rays depopulating the Coulomb-excited states were recorded by the HPGe-array MINIBALL and scattered particles were detected by a double-sided silicon strip detector. Experimental intensities were used for the determination of electromagnetic transition matrix elements. A preliminary result of the B(M1; 2+3 → 2+1) of 140Nd and an upper limit for the case of 142Sm are revealing the main fragments of the proton-neutron mixed-symmetry 2+1;ms states.

Published
2018
Full Text
View/download PDF

11. Low collectivity of the 21+ state of Po212

Author

K. Moschner, D. Kocheva, P. Van Isacker, P. Spagnoletti, A. Hennig, T. Schmidt, A. Vogt, Th. Kröll, K. A. Gladnishki, C. Müller-Gatermann, J. Litzinger, J. C. Zamora, P. Scholz, C. Fransen, V. Karayonchev, R. Altenkirch, A. Blazhev, J. Jolie, A. Astier, M. Djongolov, P. Petkov, M. Bast, Marcus Scheck, F. Diel, D. Wölk, S. Ansari, J. M. Keatings, K. O. Zell, V. Werner, E. Kluge, M. Cappellazzo, R. Stegmann, M. Beckers, Norbert Pietralla, Th. Braunroth, C. Stahl, A. Dewald, A. Goldkuhle, G. Rainovski, Alexander Stolz, N. Warr, and V. Yu. Ponomarev

Subjects
Nuclear physics, Physics, 010308 nuclear & particles physics, 0103 physical sciences, State (functional analysis), 010306 general physics, 01 natural sciences
Published
2017
Full Text
View/download PDF

12. Low collectivity of the first 2$^+$ states of $^{212,210}$Po

Author

A. Astier, A. Goldkuhle, C. Müller-Gatermann, F. Diel, D. Wölk, J. Litzinger, G. Rainovski, A. Dewald, P. Scholz, S. Ansari, Th. Braunroth, J. M. Keatings, A. Vogt, Alexander Stolz, J. Jolie, M. L. Cortés, V. Yu. Ponomarev, R. Altenkirch, C. Fransen, M. Stoyanova, Norbert Pietralla, A. Hennig, P. Spagnoletti, W. Witt, N. Warr, M. Spieker, T. Schmidt, A. Blazhev, K. O. Zell, E. Kluge, R. Stegmann, V. Karayonchev, M. Djongolov, M. Rudigier, P. Thöle, M. Beckers, M. Bast, C. Stahl, D. Kocheva, V. Werner, P. Petkov, Marcus Scheck, J. C. Zamora, Th. Kröll, K. Moschner, P. Van Isacker, M. Cappellazzo, K. A. Gladnishki, 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), 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), 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, History, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], 010308 nuclear & particles physics, Phonon, Attenuation, Yrast, Shell (structure), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Quasi particles, Computer Science Applications, Education, symbols.namesake, Recoil, Excited state, 0103 physical sciences, symbols, Atomic physics, 010306 general physics, Doppler effect
Abstract

International audience; The lifetimes of the first 2+ excited states of 212,210Po were measured in two transfer reactions 208Pb(12C,8Be)212Po and 208Pb(12C,10Be)210Po by the Recoil Distance Doppler Shift (RDDS) method and by the Doppler Shift Attenuation method (DSAM), respectively. The derived absolute B(E2) values of 2.6(3) W.u. for 212Po and 1.83(28) W.u. for 210Po indicate low collectivity. It is shown that the properties of the yrast , , and states in both nuclei cannot be described consistently in the framework of nuclear shell models. It is also demonstrated in the case of 210Po that Quasi-particle Phonon Model (QPM) calculations cannot overcome this problem thus indicating the existence of a peculiarity which is neglected in both theoretical approaches.

Published
2017
Full Text
View/download PDF

13. A revised B(E2;2+ 1 $ \rightarrow$ → 0+ 1) value in the semi-magic nucleus 210Po

Author

A. Dewald, M. Spieker, D. Kocheva, P. Scholz, C. Müller-Gatermann, R. Altenkirch, V. Karayonchev, A. Blazhev, M. Djongolov, M. Rudigier, P. Thöle, K. A. Gladnishki, Norbert Pietralla, V. Yu. Ponomarev, F. Diel, S. Ansari, D. Wölk, J. M. Keatings, N. Warr, Th. Braunroth, C. Stahl, P. Van Isacker, V. Werner, G. Rainovski, A. Astier, M. Stoyanova, A. Hennig, J. Litzinger, J. Jolie, M. L. Cortés, C. Fransen, W. Witt, K. O. Zell, E. Kluge, R. Stegmann, P. Spagnoletti, P. Petkov, and Marcus Scheck

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Phonon, Yrast, Hadron, Value (computer science), State (functional analysis), 01 natural sciences, medicine.anatomical_structure, 0103 physical sciences, medicine, Nuclear fusion, MAGIC (telescope), Atomic physics, 010306 general physics, Nucleus
Abstract

The lifetimes of the $ 2^+_1$ , the $ 2^+_2$ and the $ 3^-_1$ states of$^{210}$Po have been measured in the$^{208}$Pb($^{12}$C,$^{10}$Be)$^{210}$Po transfer reaction by the Doppler-shift attenuation method. The result for the lifetime of the $ 2^+_1$ state is about three times shorter than the adopted value. However, the new value still does not allow for a consistent description of the properties of the yrast $ 2^+_1$ , $ 4^+_1$ , $ 6^+_1$ , and $ 8^+_1$ states of$^{210}$Po in the framework of nuclear shell models. Quasi-particle Phonon Model (QPM) calculations also cannot overcome this problem thus indicating the existence of a peculiarity which is neglected in both theoretical approaches.

Published
2017
Full Text
View/download PDF

14. Inelastic scattering of 9Li and excitation mechanism of its first excited state

Author

M. Uchida, Isao Tanihata, J. N. Orce, D. S. Cross, M. Djongolov, D. Niamir, Robert B. Wiringa, A. C. Shotter, Barry Davids, Corina Andreoiu, S. Triambak, H. Al Falou, D. Howell, P.L. Walden, Aaron Gallant, Ian J. Thompson, Ritesh Kshetri, S. Sjue, R. Kanungo, and N. Galinski

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Nuclear Theory, Halo nucleus, Inelastic scattering, Deep inelastic scattering, 01 natural sciences, Inelastic neutron scattering, Excited state, 0103 physical sciences, Quadrupole, Physics::Accelerator Physics, Scattering theory, Atomic physics, 010306 general physics, Excitation
Abstract

The first measurement of inelastic scattering of 9 Li from deuterons at the ISAC facility is reported. The measured angular distribution for the first excited state confirms the nature of excitation to be an E2 transition. The quadrupole deformation parameter is extracted from an analysis of the angular distribution.

Published
2013
Full Text
View/download PDF

15. Low-lying isovector2+valence-shell excitations ofPo212

Author

A. Astier, P. Scholz, J. Litzinger, A. Dewald, Norbert Pietralla, V. Werner, V. Karayonchev, W. Witt, Thomas Braunroth, M. Djongolov, J. Jolie, M. L. Cortés, R. Stegmann, C. Müller-Gatermann, P. Petkov, Marcus Scheck, G. Rainovski, P. Thöle, D. Wölk, K. A. Gladnishki, C. Fransen, P. Van Isacker, A. Hennig, C. Stahl, D. Kocheva, and A. Blazhev

Subjects
Physics, Isovector, 010308 nuclear & particles physics, Nuclear Theory, SHELL model, 01 natural sciences, Symmetry (physics), Excited state, 0103 physical sciences, Quadrupole, Atomic physics, 010306 general physics, Spectroscopy, Valence electron, Beam (structure)
Abstract

We present the results from an experiment dedicated to search for quadrupole-collective isovector valence-shell excitations, states with so-called mixed proton-neutron symmetry (MSS), of $^{212}\mathrm{Po}$. This nucleus was studied in an $\ensuremath{\alpha}\text{-transfer}$ reaction. The lifetimes of two short-lived excited states, candidates for the one-phonon MSS, were determined by utilizing the Doppler shift attenuation method. The experimental results are in qualitative agreement with a simple $\text{single-}j$ shell model calculation, which, together with the observed lack of quadrupole collectivity, indicates that the isovector nature of low-lying states is a property of the leading single-particle valence shell configuration.

Published
2016
Full Text
View/download PDF

16. A study on the transition between seniority-type and collective excitations in 204Po and 206Po

Author

J. Jolie, J.-M. Régis, T. Kröll, K. A. Gladnishki, A. Blazhev, Lisa Gerhard, D. Kocheva, Chistian Sürder, J. M. Keatings, G. Rainovski, V. Werner, J. Wiederhold, M. Stoyanova, Marcus Scheck, Kerstin Schomacker, V. Karayonchev, M. Djongolov, J. Sinclair, Konstantin Mashtakov, Norbert Pietralla, A. Esmaylzadeh, R. Kern, and O. Möller

Subjects
Physics, Isotope, 010308 nuclear & particles physics, QC1-999, Yrast, chemistry.chemical_element, 01 natural sciences, chemistry, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Excited state, 0103 physical sciences, Quasiparticle, Seniority, Atomic physics, 010306 general physics, Polonium
Abstract

Low-lying yrast states in 204Po and 206Po have been investigated by the γ-γ fast timing technique with LaBr3(Ce) detectors. Excited states of these nuclei were populated in the 197Au(11B,4n) and the 198Pt(12C,4n) fusion-evaporation reactions, respectively, at the FN-Tandem Facility at the University of Cologne. The lifetimes of the 4+1 states in both nuclei were measured, along with an upper limit for the 2+1 state in 204Po. The preliminary results are discussed in the scope of the systematic behavior of the transition strengths between yrast states in polonium isotopes.

Published
2018
Full Text
View/download PDF

17. Narrowing of the neutron sd–pf shell gap in 29Na

Author

G. A. Demand, R. Churchman, A. A. Phillips, J. Wong, A. M. Hurst, K. L. Green, W. D. Kulp, C. J. Pearson, S. Triambak, P. M. Walker, L. Nelson, D. S. Cross, R. Maharaj, A. J. Boston, H. C. Boston, Ching-Yen Wu, C Gray-Jones, J. L. Wood, D. Bandyopadhyay, Chandana Sumithrarachchi, S. Mythili, C. J. Barton, R. A. E. Austin, M. A. Stoyer, P. E. Garrett, A. B. Hayes, Susan Rigby, G. Lee, S. J. Williams, M. Djongolov, Elizabeth Padilla-Rodal, B. A. Millar, K. G. Leach, T.E. Drake, G. Hackman, M. Porter-Peden, D. C. Oxley, Stephen Lloyd, Fred Sarazin, C. E. Svensson, G. C. Ball, S. Colosimo, A. N. Grint, M. A. Schumaker, J. P. Martin, J. A. Becker, D. Cline, and P. J. Nolan

Subjects
Physics, Nuclear and High Energy Physics, Spectrometer, ISOL, 010308 nuclear & particles physics, Island of inversion, Coulomb excitation, Nuclear Theory, Monte Carlo method, Reduced transition matrix element, 01 natural sciences, Charged particle, Semiconductor detector, Nuclear physics, 0103 physical sciences, Neutron, Atomic physics, Nuclear Experiment, 010306 general physics, Beam (structure)
Abstract

The wave-function composition for the low-lying states in 29 Na was explored by measuring their electromagnetic properties using the Coulomb-excitation technique. A beam of 29 Na ions, postaccelerated to 70 MeV, bombarded a 110 Pd target with a rate of up to 600 particles per second at the recently commissioned ISAC-II facility at TRIUMF. Six segmented HPGe clover detectors of the TIGRESS γ -ray spectrometer were used to detect deexcitation γ rays in coincidence with scattered or recoiling charged particles in the segmented silicon detector, BAMBINO. The reduced transition matrix element | 〈 5 2 1 + | | E 2 | | 3 2 gs + 〉 | in 29 Na was derived to be 0.237(21) e b from the measured γ -ray yields for both projectile and target. This first-time measured value is consistent with the most recent Monte Carlo shell-model calculation, indicating a significant admixture of both sd and pf components in the wave function, and also providing evidence for the narrowing of the neutron s d – p f shell gap from ∼ 6 MeV for stable nuclei to ∼ 3 MeV for 29 Na.

Published
2009
Full Text
View/download PDF

18. Search for mixed-symmetry states in $^{212}$Po

Author

A. Dewald, V. Werner, A. Astier, D. Kocheva, P. Van Isacker, L. Cortes, K. A. Gladnishki, C. Fransen, A. Blazhev, D. Wölk, W. Witt, C. Schramm, P. Scholz, C. Stahl, Norbert Pietralla, P. Petkov, V. Karayonchev, Marcus Scheck, M. Djongolov, P. Tölle, A. Hennig, J. Litzinger, J. Jolie, C. Müller-Gatermann, Th. Braunroth, G. Rainovski, 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), 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), 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, History, Isovector, 010308 nuclear & particles physics, Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Symmetry (physics), Computer Science Applications, Education, medicine.anatomical_structure, 0103 physical sciences, medicine, Atomic physics, 010306 general physics, Nuclear Experiment, Nucleus, Excitation
Abstract

International audience; In this work we present an experiment dedicated to searching for quarupole- collective isovector valence-shell excitation — the states with so-called mixed proton-neutron symmetry (MSSs), in the nucleus 212Po. The states of interest were populated and studied by an α-transfer reaction. The experiment provides indication for existence of one-phonon MSS in the nucleus 212Po which is the first experimentally identified MSS in the region around double magic nucleus 208Pb.

Published
2015
Full Text
View/download PDF

19. Search for mixed-symmetry states of nuclei in the vicinity of the double-magic nucleus $^{208}$Pb

Author

G. Rainovski, P. Scholz, A. Hennig, M. Djongolov, A. Dewald, P. Van Isacker, V. Karayonchev, L. Cortes, D. Kocheva, S. Zhu, R. V. F. Janssens, P. Thöle, V. Werner, M. P. Carpenter, M. Lettmann, R. Stegmann, Th. Braunroth, T. Möller, C. J. Lister, A. Blazhev, C. Fransen, Norbert Pietralla, P. Petkov, Marcus Scheck, C. Schramm, C. Möller-Gatermann, C. Bauer, K. Gladnishki, D. Wölk, C. Stahl, J. Litzinger, J. Jolie, Grand Accélérateur National d'Ions Lourds (GANIL), 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, Isovector, 010308 nuclear & particles physics, QC1-999, Nuclear Theory, Coulomb excitation, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Symmetry (physics), 3. Good health, medicine.anatomical_structure, 0103 physical sciences, medicine, MAGIC (telescope), Atomic physics, 010306 general physics, Nuclear Experiment, Nucleus, Excitation
Abstract

This is an Open Access article distributed under the terms of Creative Commons Attribution Licence 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.; International audience; In this work we present the results from two experiments dedicated to search for quadrupole-collective isovector valence-shell excitation, the states with so-called mixed proton-neutron symmetry (MSS), in nuclei around the doubly magic nucleus $^{208}$Pb. $^{212}$Po was studied in an α-transfer reaction. $^{204}$Hg was studied in an inverse kinematics Coulomb excitation reaction on a carbon target. Both experiments provide indications for existence of one-phonon MSSs. Those are the first experimentally identified MSSs in the mass A ≈ 208 region.

Published
2015
Full Text
View/download PDF

20. Investigating Single-Particle Structure in 26Na Using the New SHARC Array

Author

H Al-Falou, W. N. Catford, S. M. Brown, A. J. Boston, A. B. Garnsworthy, G. L. Wilson, Rae Austin, M. Djongolov, S. J. Williams, M. Porter-Peden, N. A. Orr, B. R. Fulton, D. S. Cross, K. G. Leach, C. Sumithrarachchi, J. N. Orce, F. Sarazin, R. Kanungo, C. Unsworth, D. S. Jamieson, André Palma da Cunha Matta, R. Ashley, P. Adsley, S. Triambak, D. Smalley, T.E. Drake, S. Sjue, J. C. Blackmon, U. Hager, N. Galinski, R. Wadsworth, I. C. Celik, Edward Simpson, C. Aa. Diget, C. J. Pearson, G. Hackman, S. P. Fox, H. C. Boston, G. C. Ball, N. L. Achouri, University of Surrey (UNIS), University of York [York, UK], 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), TRIUMF [Vancouver], University of Liverpool, Saint Mary's University [Halifax], University of Louisiana, University of Toronto, University of Guelph, and Colorado School of Mines

Subjects
Physics, Nuclear Theory, Structure (category theory), Particle, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment, 7. Clean energy, Molecular physics
Abstract

International audience; The changing of the nuclear shells for light, neutron-rich nuclei, and the single-particle nature of 26Na, has been explored by studying 25Na(d, p)26Na in inverse kinematics, using a beam of 25Na ions at 5 MeV per nucleon, provided by the ISAC-II facility at TRIUMF, Vancouver. Charged particles were detected with a highly-segmented silicon array that surrounded the 0.5 mg/cm2 (CD2)n target. Gamma rays from the recoiling 26Na nucleus were detected using eight Compton-suppressed HPGe clover detectors. Recoil tagging was provided by an in-beam scintillation foil, downstream of the germanium array. A novel technique of utilising pγ- and pγγ-gating to extract proton angular distributions from states populated close in energy was employed with success. New states in 26Na that are populated directly have been identified, using γ-decay patterns. Shell model calculations for comparison to experimental results are ongoing, using different model bases.

Published
2015
Full Text
View/download PDF

21. High-precision half-life and branching-ratio measurements for superallowed Fermi + emitters at TRIUMF - ISAC

Author

S. Triambak, A. B. Garnsworthy, Chandana Sumithrarachchi, J. Giovinazzo, Steffen Ketelhut, B. Blank, S. Chagnon-Lessard, D. Bandyopadhyay, G. Hackman, J. Wong, A. A. Phillips, A. Diaz Varela, Corina Andreoiu, E. T. Rand, I. S. Towner, D. S. Jamieson, G. C. Ball, S. J. Williams, G. F. Grinyer, G. A. Demand, M. Djongolov, C. J. Pearson, K. G. Leach, J. R. Leslie, E. F. Zganjar, D. S. Cross, C. E. Svensson, R. Dunlop, A. T. Laffoley, H. Bouzomita, C. Unsworth, K. L. Green, R. A. E. Austin, J. C. Thomas, J. Glister, A. Chester, S. W. Yates, S. Ettenauer, Baharak Hadinia, P. E. Garrett, K. Starosta, E. R. Tardiff, P. Finlay, Department of Physics [Guelph], University of Guelph, Instituut voor Kern-en Stralingsfysica (IKS), Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), 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), Department of Astronomy and Physics [Halifax], Saint Mary's University [Halifax], TRIUMF [Vancouver], Noyaux exotiques (NEX), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-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)-Centre National de la Recherche Scientifique (CNRS), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Ion beam, Isotope, half-life, Branching fraction, QC1-999, Half-life, Superallowed Fermi β decay, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, Standard Model, Nuclear physics, Isospin, Physics::Accelerator Physics, Symmetry breaking, branching ratio, Nuclear Experiment, 26Alm, Fermi Gamma-ray Space Telescope
Abstract

International audience; A program of high-precision half-life and branching-ratio measurements for superallowed Fermi emitters is being carried out at TRIUMF's Isotope Separator and Accelerator (ISAC) radioactive ion beam facility. Recent half-life measurements for the superallowed decays of 14O, 18Ne, and 26Alm, as well as branching-ratio measurements for 26Alm and 74Rb are reported. These results provide demanding tests of the Standard Model and the theoretical isospin symmetry breaking (ISB) corrections in superallowed Fermi decays.

Published
2013
Full Text
View/download PDF

22. MEASUREMENT OF THE SPECTROSCOPIC QUADRUPOLE MOMENT FOR THE $2^{+}_{1}$ STATE IN 10<font>Be</font>: TESTING AB INITIO CALCULATIONS

Author

Ruohong Li, J. N. Orce, G. Hackman, S. J. Williams, Ching-Yen Wu, M. Djongolov, C. E. Svensson, Petr Navrátil, S. Triambak, E. T. Rand, Corina Andreoiu, S. Sjue, A. B. Hayes, A. Teigelhoefer, A. B. Garnsworthy, Jens Lassen, K. G. Leach, P. E. Garrett, H. Al Falou, F. Sarazin, J. Meissner, Ritesh Kshetri, M. A. Stoyer, J. Wong, T.E. Drake, Christian Forssén, Chandana Sumithrarachchi, E. R. Tardiff, P. Finlay, C. J. Pearson, G. C. Ball, L. Milovanovic, and D. S. Cross

Subjects
Physics, Computational chemistry, Ab initio quantum chemistry methods, Quadrupole, State (functional analysis), Atomic physics
Published
2013
Full Text
View/download PDF

23. HIGH-PRECISION HALF-LIFE AND BRANCHING RATIO MEASUREMENTS FOR THE SUPERALLOWED β+ EMITTER 26<font>Al</font>m

Author

P. FINLAY, C. E. SVENSSON, G. A. DEMAND, P. E. GARRETT, K. L. GREEN, K. G. LEACH, A. A. PHILLIPS, E. T. RAND, G. BALL, D. BANDYOPADHYAY, M. DJONGOLOV, S. ETTENAUER, G. HACKMAN, C. J. PEARSON, J. R. LESLIE, C. ANDREOIU, D. CROSS, R. A. E. AUSTIN, G. F. GRINYER, C. S. SUMITHRARACHCHI, S. J. WILLIAMS, and S. TRIAMBAK

Subjects
Nuclear physics, Physics, Branching fraction, Half-life, Atomic physics, Beta decay, Standard Model
Published
2013
Full Text
View/download PDF

24. Superallowed Fermi β decay studies at TRIUMF-ISAC

Author

S. W. Yates, A. B. Garnsworthy, S. Ettenauer, G. Hackman, G. C. Ball, M. Djongolov, J. Glister, Chandana Sumithrarachchi, Aaron Chester, D. S. Cross, S. Chagnon-Lessard, R. Dunlop, K. L. Green, D. Bandyopadhyay, K. Starosta, Corina Andreoiu, A. A. Phillips, E. R. Tardiff, J. Wong, E. T. Rand, P. Finlay, S. J. Williams, P. E. Garrett, Baharak Hadinia, S. Triambak, I. S. Towner, G. A. Demand, G. F. Grinyer, K. G. Leach, C. J. Pearson, R. A. E. Austin, J. R. Leslie, C. E. Svensson, and E. F. Zganjar

Subjects
Nuclear physics, Physics, Particle physics, Isotope, Ion beam, Branching fraction, Isospin, Physics::Accelerator Physics, Symmetry breaking, Nuclear Experiment, Fermi Gamma-ray Space Telescope, Common emitter
Abstract

A program of high-precision superallowed Fermi β decay studies is being carried out at the Isotope Separator and Accelerator (ISAC) radioactive ion beam facility at TRIUMF. Recent high-precision branching ratio measurements for the superallowed decays of 74Rb and 26Alm, as well as a half-life measurement for 26Alm that is the most precise half-life measurement for any superallowed emitter to date, are reported. These results provide demanding tests of the theoretical isospin symmetry breaking corrections in superallowed Fermi β decays.

Published
2013
Full Text
View/download PDF

25. Reorientation-effect measurement of the〈21+∥E2̂∥21+〉matrix element in10Be

Author

G. Hackman, A. B. Garnsworthy, Chandana Sumithrarachchi, E. R. Tardiff, A. Teigelhoefer, P. Finlay, Petr Navrátil, J. N. Orce, F. Sarazin, D. S. Cross, Jens Lassen, J. Meissner, S. Sjue, Ruohong Li, Ritesh Kshetri, S. Triambak, P. E. Garrett, S. J. Williams, E. T. Rand, J. Wong, R. Churchman, C. E. Svensson, G. C. Ball, K. G. Leach, Ching-Yen Wu, H. Al Falou, C. J. Pearson, A. B. Hayes, M. Djongolov, Christian Forssén, T.E. Drake, and M. A. Stoyer

Subjects
Physics, Nuclear and High Energy Physics, Work (thermodynamics), Spectrometer, Excited state, Nuclear Theory, Quadrupole, Diagonal matrix, Monte Carlo method, Function (mathematics), Coulomb excitation, Atomic physics
Abstract

The highly-efficient and segmented TIGRESS gamma-ray spectrometer at TRIUMF has been used to perform a reorientation-effect Coulomb-excitation study of the 2(1)(+) state at 3.368 MeV in Be-10. This is the first Coulomb-excitation measurement that enables one to obtain information on diagonal matrix elements for such a high-lying first excited state from gamma-ray data. With the availability of accurate lifetime data, a value of -0.110 +/- 0.087 eb is determined for the diagonal matrix element, which assuming the rotor model, leads to a negative spectroscopic quadrupole moment of Q(S)(2(1)(+)) = -0.083 +/- 0.066 eb. This result is in agreement with both no-core shell-model calculations performed in this work with the CD-Bonn 2000 two-nucleon potential and large shell-model spaces, and Green's function Monte Carlo predictions with two-plus three-nucleon potentials.

Published
2012
Full Text
View/download PDF

26. High-Precision Measurement of theNe19Half-Life and Implications for Right-Handed Weak Currents

Author

G. Hackman, S. Triambak, L. Milovanovic, Ritesh Kshetri, R. A. E. Austin, D. S. Cross, J. N. Orce, E. R. Tardiff, C. Kierans, M. R. Pearson, S. O’Hagan, Chandana Sumithrarachchi, P. Finlay, S. Reeve, S. Sjue, S. J. Williams, H. Al-Falou, M. Djongolov, R. Churchman, A. B. Garnsworthy, P. E. Garrett, C. E. Svensson, G. C. Ball, and R. D’Entremont

Subjects
Physics, Particle physics, Current (mathematics), Right handed, 010308 nuclear & particles physics, 0103 physical sciences, General Physics and Astronomy, 010306 general physics, 01 natural sciences, Standard Model
Abstract

We report a precise determination of the $^{19}\mathrm{Ne}$ half-life to be ${T}_{1/2}=17.262\ifmmode\pm\else\textpm\fi{}0.007\text{ }\text{ }\mathrm{s}$. This result disagrees with the most recent precision measurements and is important for placing bounds on predicted right-handed interactions that are absent in the current standard model. We are able to identify and disentangle two competing systematic effects that influence the accuracy of such measurements. Our findings prompt a reassessment of results from previous high-precision lifetime measurements that used similar equipment and methods.

Published
2012
Full Text
View/download PDF

27. High-precision branching-ratio measurement for the superallowedβ+emitter26Alm

Author

S. Ettenauer, S. Triambak, Corina Andreoiu, J. R. Leslie, C. E. Svensson, G. Hackman, K. G. Leach, M. Djongolov, S. J. Williams, E. T. Rand, Chandana Sumithrarachchi, D. S. Cross, P. E. Garrett, D. Bandyopadhyay, P. Finlay, G. F. Grinyer, G. C. Ball, K. L. Green, C. J. Pearson, R. A. E. Austin, A. A. Phillips, and G. A. Demand

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Branching fraction, Double beta decay, 0103 physical sciences, 010306 general physics, 01 natural sciences, Beta decay, Common emitter
Published
2012
Full Text
View/download PDF

28. High-Precision Half-Life Measurement for the Superallowedβ+EmitterAlm26

Author

G. Hackman, Corina Andreoiu, C. J. Pearson, J. R. Leslie, C. E. Svensson, P. E. Garrett, G. A. Demand, S. Ettenauer, D. S. Cross, K. L. Green, S. Triambak, S. J. Williams, G. F. Grinyer, R. A. E. Austin, Chandana Sumithrarachchi, A. A. Phillips, M. Djongolov, D. Bandyopadhyay, P. Finlay, K. G. Leach, and G. C. Ball

Subjects
Quark, Physics, Particle physics, Cabibbo–Kobayashi–Maskawa matrix, Isospin, Double beta decay, General Physics and Astronomy, Half-life, High Energy Physics::Experiment, Fermion, Symmetry breaking, Nuclear Experiment, Radioactive decay
Abstract

A high-precision half-life measurement for the superallowed ${\ensuremath{\beta}}^{+}$ emitter $^{26}\mathrm{Al}^{m}$ was performed at the TRIUMF-ISAC radioactive ion beam facility yielding ${T}_{1/2}=6346.54\ifmmode\pm\else\textpm\fi{}{0.46}_{\mathrm{stat}}\ifmmode\pm\else\textpm\fi{}{0.60}_{\mathrm{syst}}\text{ }\text{ }\mathrm{ms}$, consistent with, but 2.5 times more precise than, the previous world average. The $^{26}\mathrm{Al}^{m}$ half-life and $ft$ value, 3037.53(61) s, are now the most precisely determined for any superallowed $\ensuremath{\beta}$ decay. Combined with recent theoretical corrections for isospin-symmetry-breaking and radiative effects, the corrected $\mathcal{F}t$ value for $^{26}\mathrm{Al}^{m}$, 3073.0(12) s, sets a new benchmark for the high-precision superallowed Fermi $\ensuremath{\beta}$-decay studies used to test the conserved vector current hypothesis and determine the ${V}_{ud}$ element of the Cabibbo-Kobayashi-Maskawa quark mixing matrix.

Published
2011
Full Text
View/download PDF

29. Towards Na-26 via (d,p) with SHARC and TIGRESS and a novel zero-degree detector

Author

M. Djongolov, M. Porter-Peden, H. J. Boston, S. M. Brown, C. Aa. Diget, Jun Chen, C. Unsworth, N. Galinski, U. Hager, N. A. Orr, D. S. Cross, R. Churchman, J. N. Orce, A. B. Garnsworthy, A. Chen, G. Hackman, S. Sjue, C. J. Pearson, C. E. Svensson, G. L. Wilson, R. Kanungo, J. Dech, W. N. Catford, S. J. Williams, B. R. Fulton, A. J. Boston, R. A. E. Austin, F. Sarazin, R. Ashley, P. Adsley, T.E. Drake, R. Wadsworth, S. P. Fox, D. S. Jamieson, J. P. Martin, G. C. Ball, H. Al-Falou, K. G. Leach, S. Triambak, J. C. Blackmon, C. Sumithrarachchi, 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), and Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Nuclear reaction, History, Proton, 010308 nuclear & particles physics, Detector, Scintillator, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Particle detector, Computer Science Applications, Education, Semiconductor detector, Nuclear physics, 0103 physical sciences, Scintillation counter, 010306 general physics, Nucleon, Nuclear Experiment
Abstract

Nucleon transfer experiments have in recent years begun to be exploited in the study of nuclei far from stability, using radioactive beams in inverse kinematics. New techniques are still being developed in order to perform these experiments. The present experiment is designed to study the odd-odd nucleus Na which has a high density of states and therefore requires gamma-ray detection to distinguish between them. The experiment employed an intense beam of up to 3×10 pps of Na at 5.0 MeV/nucleon from the ISAC-II facility at triumf. The new silicon array SHARC was used for the first time and was coupled to the segmented clover gamma-ray array TIGRESS. A novel thin plastic scintillator detector was employed at zero degrees to identify and reject reactions occurring on the carbon component of the (CD) target. The efficiency of the background rejection using this detector is described with respect to the proton and gamma-ray spectra from the (d,p) reaction. © Published under licence by IOP Publishing Ltd.

Published
2011
Full Text
View/download PDF

30. High-precision half-life measurement for the superallowed β+ emitter ²⁶Al(m)

Author

P, Finlay, S, Ettenauer, G C, Ball, J R, Leslie, C E, Svensson, C, Andreoiu, R A E, Austin, D, Bandyopadhyay, D S, Cross, G, Demand, M, Djongolov, P E, Garrett, K L, Green, G F, Grinyer, G, Hackman, K G, Leach, C J, Pearson, A A, Phillips, C S, Sumithrarachchi, S, Triambak, and S J, Williams

Subjects
Radioisotopes, Aluminum, Beta Particles, Half-Life
Abstract

A high-precision half-life measurement for the superallowed β+ emitter 26Al(m) was performed at the TRIUMF-ISAC radioactive ion beam facility yielding T 1/2 6346.54 ± 0.46(stat) ± 0.60 (syst) ms, consistent with, but 2.5 times more precise than, the previous world average. The 26Al(m) half-life and ft value, 3037.53(61) s, are now the most precisely determined for any superallowed β decay. Combined with recent theoretical corrections for isospin-symmetry-breaking and radiative effects, the corrected Ft value for (26)Al(m), 3073.0(12) s, sets a new benchmark for the high-precision superallowed Fermi β-decay studies used to test the conserved vector current hypothesis and determine the V(ud) element of the Cabibbo-Kobayashi-Maskawa quark mixing matrix.

Published
2010

31. First Results with TIGRESS and Accelerated Radioactive Ion Beams from ISAC: Coulomb Excitation of [sup 20,21,29]Na

Author

M. A. Schumaker, A. M. Hurst, C. E. Svensson, C. Y. Wu, J. A. Becker, D. Cline, G. Hackman, C. J. Pearson, M. A. Stoyer, A. Andreyev, R. A. E. Austin, G. C. Ball, D. Bandyopadhyay, C. J. Barton, A. J. Boston, H. C. Boston, L. Buchmann, R. Churchman, F. Cifarelli, S. J. Colosimo, R. J. Cooper, D. S. Cross, D. Dashdorj, G. A. Demand, M. R. Dimmock, M. Djongolov, T. E. Drake, P. Finlay, A. T. Gallant, P. E. Garrett, C. Gray-Jones, K. L. Green, A. N. Grint, G. F. Grinyer, L. J. Harkness, A. B. Hayes, R. Kanungo, K. G. Leach, W. D. Kulp, A. F. Lisetskiy, G. Lee, S. Lloyd, R. Maharaj, J.-P. Martin, B. A. Millar, F. Moisan, A. C. Morton, S. Mythili, L. Nelson, O. Newman, P. J. Nolan, J. N. Orce, D. C. Oxley, E. Padilla-Rodal, A. A. Phillips, M. Porter-Peden, J. J. Ressler, S. V. Rigby, R. Roy, C. Ruiz, F. Sarazin, D. P. Scraggs, C. S. Sumithrarachchi, S. Triambak, J. C. Waddington, P. M. Walker, J. Wan, A. Whitbeck, S. J. Williams, J. Wong, J. L. Wood, Floyd D. McDaniel, and Barney L. Doyle

Subjects
Nuclear physics, Physics, Spectrometer, Ion beam, law, Scintillation counter, Cyclotron, Gamma spectroscopy, Coulomb excitation, Particle detector, Semiconductor detector, law.invention
Abstract

The TRIUMF‐ISAC Gamma‐Ray Escape Suppressed Spectrometer (TIGRESS) is a state‐of‐the‐art γ‐ray spectrometer being constructed at the ISAC‐II radioactive ion beam facility at TRIUMF. TIGRESS will be comprised of twelve 32‐fold segmented high‐purity germanium (HPGe) clover‐type γ‐ray detectors, with BGO∕CsI(Tl) Compton‐suppression shields, and is currently operational at ISAC‐II in an early‐implementation configuration of six detectors. Results have been obtained for the first experiments performed using TIGRESS, which examined the A = 20, 21, and 29 isotopes of Na by Coulomb excitation.

Published
2009
Full Text
View/download PDF

32. Erratum: High-spin states inAu191,193andPt192: Evidence for oblate deformation and triaxial shapes [Phys. Rev. C 76, 044315 (2007)]

Author

A. A. Hecht, L. L. Riedinger, R. Krücken, M. Djongolov, M. N. Erduran, R. B. Cakirli, N. Nikolov, S. Erturk, G. Rainovski, M. Danchev, G. Gurdal, N. V. Zamfir, K. A. Gladniski, D. J. Hartley, D. L. Balabanski, R. F. Casten, I. Yigitoglu, Baki Akkuş, M. Bostan, Y. Oktem, J. R. Novak, O. Zeidan, J. Tm. Goon, and C. W. Beausang

Subjects
Physics, Nuclear and High Energy Physics, Spin states, Condensed matter physics, Oblate spheroid, Deformation (meteorology), Atomic physics
Published
2008
Full Text
View/download PDF

33. Erratum: Multiple band structures inTa169[Phys. Rev. C74, 054314 (2006)]

Author

M. Djongolov, P. Chowdhury, W. H. Mohr, M. A. Riley, M. Danchev, R. V. F. Janssens, J. R. Vanhoy, E. F. Moore, C. Teal, S. W. Ødegård, D. J. Hartley, A. A. Hecht, W. C. Ma, S. Zhu, L. L. Riedinger, S. K. Tandel, M. P. Carpenter, G. Sletten, G.B. Hagemann, A. Aguilar, T. Lauritsen, and F. G. Kondev

Subjects
Physics, Nuclear and High Energy Physics, Nuclear structure, Atomic physics, Electronic band structure
Published
2007
Full Text
View/download PDF

34. Structure of $^{26}$Na via a Novel Technique Using ($d,p\gamma $) with a Radioactive $^{25}$Na Beam

Author

W. N. Catford, A. J. Boston, J. C. Blackmon, C. Sumithrarachchi, N. Galinski, R. A. E. Austin, C. E. Svensson, H. Al-Falou, I. C. Celik, C. Unsworth, K. G. Leach, A. B. Garnsworthy, S. J. Williams, T.E. Drake, F. Sarazin, G. C. Ball, N. A. Orr, G. L. Wilson, G. Hackman, C. J. Pearson, S. M. Brown, D. S. Cross, C. Aa. Diget, R. Ashley, P. Adsley, H. C. Boston, S. Triambak, B. R. Fulton, S. Sjue, U. Hager, A. Matta, M. Djongolov, M. Porter-Peden, R. Wadsworth, J. N. Orce, J. P. Martin, R. Kanungo, S. P. Fox, D. S. Jamieson, 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), and Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Novel technique, Physics, Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, SHELL model, General Physics and Astronomy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Coincidence, Ion, Nuclear physics, Deuterium, Physics::Accelerator Physics, Neutron, Atomic physics, Nuclear Experiment, Beam (structure)
Abstract

International audience; States in 26Na were populated in the (d, pγ) reaction, induced by bombarding deuterium target nuclei with an intense reaccelerated beam of 25Na ions from the ISAC2 accelerator at TRIUMF. Gamma-rays were recorded in coincidence with protons and used to extract differential cross sections for 21 states up to the neutron decay threshold of 5 MeV. Results for levels below 3 MeV are discussed in detail and compared with shell model calculations and with previous work. The angular distributions of decay gamma-rays were measured for individual states and are compared to theoretically calculated distributions, highlighting some issues for future work.

Published
2015
Full Text
View/download PDF

35. Highly Deformed Bands in Hf-175

Author

Andreas Martin Heinz, I. Shestakova, G.D. Dracoulis, K. Abu Saleem, G. Sletten, H. El-Masri, T. L. Khoo, R. V. F. Janssens, O. Zeidan, E. F. Moore, M. A. Riley, C. Wheldon, F. G. Kondev, P. M. Walker, D. L. Balabanski, D. Seweryniak, D. J. Hartley, T. Lauritsen, I. Wiedenhöver, J. Goon, M. Danchev, L. L. Riedinger, G.B. Hagemann, J. Y. Zhang, P. Chowdhury, C. J. Lister, D. M. Cullen, M. P. Carpenter, R. A. Kaye, Iftikhar Ahmad, M. Djongolov, and D. T. Scholes

Subjects
Physics, Nuclear and High Energy Physics, Spectrometer, Nuclear Theory, Nuclear structure, chemistry.chemical_element, Moment of inertia, Polarization (waves), Nuclear shape, Hafnium, chemistry, Gammasphere, Atomic physics, Nuclear Experiment
Abstract

Two high-spin regularly spaced rotational bands with large dynamical moments of inertia have been identified in Hf-175 with the Gammasphere spectrometer. These new bands are very similar to the previously identified triaxial superdeformed bands in the hafnium nuclei. However, the new bands in Hf-175 have been linked into the known level scheme and thereby provide the first firm spin assignments for these structures in this region. In order to understand the new bands, theoretical calculations have been performed based on the ULTIMATE CRANKER code. The new bands in Hf-175 are deduced to be built upon highly deformed structures. No experimental evidence for triaxiality was established and this work suggests that the structure of the so-called "triaxial" superdeformed bands in the Hf nuclei may be quite different from those identified in the lighter mass Lu nuclei. Since the two highly deformed bands in Hf-175 are associated with different deformations, this work also identifies the role of the intruder orbits in polarizing the nuclear shape.

Published
2004

36. Multiphonon vibrations at high angular momentum in 182 Os

Author

L K, Pattison, D M, Cullen, J F, Smith, A M, Fletcher, P M, Walker, H M, El-Masri, Zs, Podolyák, R J, Wood, C, Scholey, C, Wheldon, G, Mukherjee, D, Balabanski, M, Djongolov, Th, Dalsgaard, H, Thisgaard, G, Sletten, F, Kondev, D, Jenkins, G J, Lane, I-Y, Lee, A O, Macchiavelli, S, Frauendorf, and D, Almehed

Abstract

Evidence is presented for multiphonon excitations based on a high-spin (25 Planck) intrinsic state in the deformed nucleus 182 Os. Angular momentum generation by this mode competes with collective rotation. The experimental data are compared with tilted-axis cranking calculations, supporting the vibrational interpretation. However, the lower experimental energies provide evidence that more complex interactions of states are playing a role.

Published
2002

37. Structure of High-Spin States in 90<font>Sr</font> and 92<font>Sr</font>

Author

M. Djongolov, J. Eberth, O. Thelen, A. Gadea, E. Galindo, F. Dönau, K. D. Schilling, D. L. Balabanski, T. Martinez, W. F. Mueller, E. A. Stefanova, M. Axiotis, G. Rainovski, N. Marginean, O. Zeidan, Ronald Schwengner, Th. Kröll, D. J. Hartley, D. R. Napoli, G. de Angelis, M. Danchev, A. Jungclaus, Andreas Wagner, K. P. Lieb, C. A. Ur, T. Kutsarova, W. Reviol, and L. L. Riedinger

Subjects
Physics, Condensed matter physics, Spin states, Structure (category theory)
Published
2001
Full Text
View/download PDF

38. Structure of states in 12Be via the 11Be(d,p) reaction

Author

B. Pietras, L. Buchmann, K. G. Leach, P. E. Garrett, Camilo Ruiz, Henrik B. Jeppesen, R.A.E. Austin, A.C. Shotter, C. J. Pearson, F. Sarazin, C. E. Svensson, P. Finlay, A. A. Phillips, G. Hackman, D. S. Cross, D. C. Oxley, J. Wong, C. Unsworth, M. Uchida, D. Bandyopadhyay, D. Cline, S. Grist, S. Triambak, A.T. Gallant, S. J. Williams, K. L. Green, N. Galinski, A. M. Hurst, P.L. Walden, H. C. Boston, G. C. Ball, D. Howell, S.J. Colosimo, H. Dare, T.E. Drake, M. A. Schumaker, Götz Ruprecht, A. J. Boston, R. M. Clark, A. O. Macchiavelli, L. J. Harkness, M. Djongolov, C.S. Sumitharachchi, Ching-Yen Wu, J. A. Becker, A. B. Garnsworthy, Barry Davids, A. B. Hayes, Isao Tanihata, Rituparna Kanungo, Corina Andreoiu, B. A. Brown, and Susan Rigby

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, SHELL model, 01 natural sciences, Shell structure, Transfer reactions, Inverse kinematics, Excited state, 0103 physical sciences, Bound state, Neutron, Atomic physics, 010306 general physics, Ground state, Beam (structure), Radioactive beams
Abstract

The s-wave neutron fraction of the 0 + levels in 12Be has been investigated for the first time through the 11Be( d , p ) transfer reaction using a 5 A MeV 11Be beam at TRIUMF, Canada. The reaction populated all the known bound states of 12Be. The ground state s-wave spectroscopic factor was determined to be 0.28 − 0.07 + 0.03 while that for the long-lived 0 2 + excited state was 0.73 − 0.40 + 0.27 . This observation, together with the smaller effective separation energy indicates enhanced probability for an extended density tail beyond the 10Be core for the 0 2 + excited state compared to the ground state.

Full Text
View/download PDF

39. Restoring the valence-shell stabilization in Nd 140

Author

H. De Witte, J. Snäll, O. Möller, Liam Gaffney, E. Giannopoulos, J. G. Cubiss, A. Blazhev, Radostina Zidarova, Amar Boukhari, D. Rosiak, V. Karayonchev, P. Reiter, M. Djongolov, N. Warr, P. Spagnoletti, A. Vogt, J. Jolie, D. Kocheva, M. Stoyanova, G. G. O'Neill, V. Werner, S. Thiel, P. A. Söderström, G. Rainovski, J. Wiederhold, Herbert Hess, K. A. Gladnishki, Norbert Pietralla, Marcus Scheck, Th. Kröll, Joakim Cederkäll, R. Stegmann, R. Kern, J. M. Keatings, A. Welker, C. Fransen, L. Kaya, Janne Pakarinen, and Helsinki Institute of Physics

Subjects
Physics, Science & Technology, Proton, 010308 nuclear & particles physics, Projectile, MIXED-SYMMETRY, Stochastic matrix, Analytical chemistry, Coulomb excitation, PROTON, 114 Physical sciences, 01 natural sciences, Physics, Nuclear, STATES, Physical Sciences, 0103 physical sciences, Matrix element, 010306 general physics, Valence electron, Beam (structure), Mixing (physics)
Abstract

A projectile Coulomb-excitation experiment was performed at the radioactive-ion beam facility HIE-ISOLDE at CERN to obtain E2 and M1 transition matrix elements of Nd-140 using the multistep Coulomb-excitation code GOSIA. The absolute M1 strengths, B(M1; 2(2)(-) -> 2(1)(+)) = 0.033(8)mu(2)(N), B(M1 ; 2(3)(+) -> 2(1)(+)) = 0.26(-0.10)(+0.11)mu(2)(N), and B(M1; 2(4)+ -> 2(1)(+))

Full Text
View/download PDF

40. Low collectivity of the first 2+ states of 212,210Po.

Author

D. Kocheva, G. Rainovski, J. Jolie, N. Pietralla, A. Blazhev, A. Astier, R. Altenkirch, M. Bast, M. Beckers, S. Ansari, Th. Braunroth, M. Cappellazzo, M.L. Cortés, A. Dewald, F. Diel, M. Djongolov, C. Fransen, K. Gladnishki, A. Goldkuhle, and A. Hennig

Published
2018
Full Text
View/download PDF

41. Search for mixed-symmetry states in 212Po.

Author

D. Kocheva, G. Rainovski, J. Jolie, N. Pietralla, C. Stahl, P. Petkov, A. Blazhev, A. Hennig, A. Astier, Th. Braunroth, L. Cortes, A. Dewald, M. Djongolov, C. Fransen, K. Gladnishki, V. Karayonchev, J. Litzinger, C. Müller-Gatermann, M. Scheck, and Ph. Scholz

Published
2016
Full Text
View/download PDF

42. High-spin states in (191,193)Au and (192)Pt: Evidence for oblate deformation and triaxial shapes

Author

Oktem, Y., Balabanski, D. L., Akkus, B., Beausang, W., Bostan, M., Cakirli, R. B., Casten, R. F., Danchev, M., Djongolov, M., Erduran, M. N., Erturk, S., Gladniski, K. A., Gurdal, G., Goon, J. Tm., Hartley, D. J., Hecht, A. A., Krucken, R., Nikolov, N., Novak, J. R., Rainovski, G., Riedinger, L. L., Yigitoglu, I., Zamfir, N. V., Zeidan, O., Rainovski, Georgi -- 0000-0002-1729-0249, Kruecken, Reiner -- 0000-0002-2755-8042, and [Oktem, Y. -- Akkus, B. -- Bostan, M. -- Cakirli, R. B. -- Erduran, M. N.] Univ Istanbul, Dept Phys, TR-34459 Istanbul, Turkey -- [Balabanski, D. L.] Bulgarian Acad Sci, Inst Nucl Res & Nucl Energy, BG-1784 Sofia, Bulgaria -- [Beausang, W. -- Casten, R. F. -- Hecht, A. A. -- Krucken, R. -- Novak, J. R. -- Zamfir, N. V.] Yale Univ, Wright Nucl Struct Lab, New Haven, CT 06520 USA -- [Beausang, W.] Univ Richmond, Dept Phys, Richmond, VA 23173 USA -- [Danchev, M. -- Djongolov, M. -- Hartley, D. J. -- Nikolov, N. -- Riedinger, L. L. -- Zeidan, O.] Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA -- [Erturk, S.] Nigde Univ, Dept Phys, TR-51200 Nigde, Turkey -- [Gladniski, K. A. -- Nikolov, N. -- Rainovski, G.] St Kliment Ohridski Univ Sofia, Fac Phys, BG-1164 Sofia, Bulgaria -- [Gurdal, G.] Clark Univ, Worcester, MA 01610 USA -- [Goon, J. Tm.] Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA -- [Hartley, D. J.] USN Acad, Dept Phys, Annapolis, MD 21402 USA -- [Hecht, A. A.] Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA -- [Yigitoglu, I.] Istanbul Univ, Hasan Ali Yucel Fac Educ, TR-34470 Istanbul, Turkey -- [Zamfir, N. V.] Natl Inst Phys & Nucl Engn, Bucharest, Romania

Abstract

WOS: 000250620900030, High-spin states of (191,193)Au and (192)Pt have been populated in the (186)W((11)B, xn) and (186)W((11)B, p4n) reactions, respectively, at a beam energy of 68 MeV and their gamma decay was studied using the YRAST Ball detector array at the Wright Nuclear Structure Laboratory at Yale University. The level scheme of (193)Au has been extended up to I(pi)=55/2(+). New transitions were observed also in (191)Au and (192)Pt. Particle-plus-Triaxial-Rotor (PTR) and Total Routhian Surface (TRS) calculations were performed to determine the equilibrium deformations of the Au isotopes. The predictions for oblate deformations in these nuclei are in agreement with the experimental data. Development of nonaxial shapes is discussed within the framework of the PTR model.

Published
2007

43. High-precision half-life measurement for the superallowed β+ emitter ²⁶Al(m).

Author

Finlay P, Ettenauer S, Ball GC, Leslie JR, Svensson CE, Andreoiu C, Austin RA, Bandyopadhyay D, Cross DS, Demand G, Djongolov M, Garrett PE, Green KL, Grinyer GF, Hackman G, Leach KG, Pearson CJ, Phillips AA, Sumithrarachchi CS, Triambak S, and Williams SJ

Subjects
Half-Life, Aluminum chemistry, Beta Particles, Radioisotopes chemistry
Abstract

A high-precision half-life measurement for the superallowed β+ emitter 26Al(m) was performed at the TRIUMF-ISAC radioactive ion beam facility yielding T 1/2 6346.54 ± 0.46(stat) ± 0.60 (syst) ms, consistent with, but 2.5 times more precise than, the previous world average. The 26Al(m) half-life and ft value, 3037.53(61) s, are now the most precisely determined for any superallowed β decay. Combined with recent theoretical corrections for isospin-symmetry-breaking and radiative effects, the corrected Ft value for (26)Al(m), 3073.0(12) s, sets a new benchmark for the high-precision superallowed Fermi β-decay studies used to test the conserved vector current hypothesis and determine the V(ud) element of the Cabibbo-Kobayashi-Maskawa quark mixing matrix.

Published
2011
Full Text
View/download PDF

44. Multiphonon vibrations at high angular momentum in 182 Os.

Author

Pattison LK, Cullen DM, Smith JF, Fletcher AM, Walker PM, El-Masri HM, Podolyák Z, Wood RJ, Scholey C, Wheldon C, Mukherjee G, Balabanski D, Djongolov M, Dalsgaard T, Thisgaard H, Sletten G, Kondev F, Jenkins D, Lane GJ, Lee IY, Macchiavelli AO, Frauendorf S, and Almehed D

Abstract

Evidence is presented for multiphonon excitations based on a high-spin (25 Planck) intrinsic state in the deformed nucleus 182 Os. Angular momentum generation by this mode competes with collective rotation. The experimental data are compared with tilted-axis cranking calculations, supporting the vibrational interpretation. However, the lower experimental energies provide evidence that more complex interactions of states are playing a role.

Published
2003
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results