Abstract
Heavy neutron-rich nuclei have been populated through the relativistic fragmentation of a \(\ensuremath ^{208}_{\ 82}{\rm Pb}\) beam at \(\ensuremath E/A = 1\) GeV on a \(\ensuremath 2.5 {\rm g/cm^2}\) thick Be target. The synthesised nuclei were selected and identified in-flight using the fragment separator at GSI. Approximately 300 ns after production, the selected nuclei were implanted in an \(\ensuremath \sim 8\) mm thick perspex stopper, positioned at the centre of the RISING \(\ensuremath \gamma\) -ray detector spectrometer array. A previously unreported isomer with a half-life \(\ensuremath T_{1/2} = 163(5)\) ns has been observed in the N = 126 closed-shell nucleus \(\ensuremath ^{205}_{\ 79}{\rm Au}\) . Through \( \gamma\) -ray singles and \( \gamma\) -\( \gamma\) coincidence analysis a level scheme was established. The comparison with a shell model calculation tentatively identifies the spin-parity of the excited states, including the isomer itself, which is found to be \(\ensuremath I^{\pi} = (19/2^+)\) .
Similar content being viewed by others
References
B. Fornal et al., Phys. Rev. Lett. 87, 212501 (2001).
R. Grzywacz et al., Phys. Lett. B 355, 439 (1995).
M. Pfützner et al., Phys. Lett. B 444, 32 (1998).
M. Caamano et al., Eur. Phys. J. A 23, 201 (2005).
Zs. Podolyák et al., Phys. Lett. B 491, 225 (2000).
H. Grawe, K. Langanke, G. Martinez-Pinedo, Rep. Prog. Phys. 70, 1525 (2007).
S.J. Steer et al., to be published in Int. J. Mod. Phys. E.
S.J. Steer et al., in preparation.
S.J. Steer, PhD Thesis, University of Surrey, 2008, unpublished.
S.J. Steer et al., Phys. Rev. C 78, 061302(R) (2008).
H. Geissel et al., Nucl. Instrum. Methods B 70, 286 (1992).
S. Pietri et al., Nucl. Instrum. Methods B 261, 1079 (2007).
P.H. Regan et al., Nucl. Phys. A 787, 491c (2007).
Zs. Podolyák et al., Eur. Phys. J. ST 150, 165 (2007).
M. Pfützner et al., Phys. Rev. C 65, 064604 (2002).
B.A. Brown, A. Etchegoyen, W.D.M. Rae, The computer code OXBASH, MSU-NSCL report no. 524.
D. Eccleshall, M.J.L. Yates, Phys. Lett. 19, 301 (1965); M.J. Martin, Nucl. Data Sheets 70, 315 (1993).
L. Rydström et al., Nucl. Phys. A 512, 217 (1990).
T.T.S. Kuo, G.H. Herling, Naval Research Laboratory Report 2259 (Washington, DC, 1971).
G.H. Herling, T.T.S. Kuo, Nucl. Phys. A 181, 113 (1972).
Zs. Podolyák et al., Phys. Lett. B 672, 116 (2009).
R. Kumar et al., Nucl. Instrum. Methods A 598, 754 (2009).
N. Alkhomashi et al., Acta Phys. Pol. B 40, 875 (2009).
P.H. Regan et al., Int. J. Mod. Phys. E Suppl. 17, 8 (2008).
A.I. Morales et al., Acta Phys. Pol. B 40, 867 (2009).
N. Al-Dahan et al., Acta Phys. Pol. B 40, 871 (2009).
Author information
Authors and Affiliations
Corresponding author
Additional information
Communicated by J. Äystö
Rights and permissions
About this article
Cite this article
Podolyák, Z., Steer, S.J., Pietri, S. et al. Structure of neutron-rich nuclei around the N = 126 closed shell; the yrast structure of 205Au126 up to spin-parity \(I^{\pi}\) = (19/2+). Eur. Phys. J. A 42, 489–493 (2009). https://doi.org/10.1140/epja/i2009-10794-5
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1140/epja/i2009-10794-5