Rotational structures near 40h in La-123

The neutron-deficient nucleus La-123 was studied via the Mo-92(Ca-40,2ap) reaction at a beam energy of 184 MeV. Previously known bands were extended to a much higher spin, and in two cases the structures are now observed near 40 (h) over bar. In addition, three new sequences were identified and linked into previously known bands. The lowest (pi,alpha)=(+,-1/2) structure displays characteristics similar to those of analogous bands in La-127,La-129, which have been proposed as examples of smooth band termination. Cranked Nilsson-Strutinsky calculations were compared with the experimental data in La-123 to determine whether this band is approaching a terminating state as well.

[1]  M. Nespolo,et al.  High-spin states in the deformed 122Ba nucleus , 2001 .

[2]  T. Kibédi,et al.  Candidate chiral band in 134 La , 2001 .

[3]  J. Wilson,et al.  High-spin structures and alignment properties in 126 Ce , 2001 .

[4]  C. T. Zhang,et al.  Competition between terminating and collective structures above spin 40 hbar in 154Dy , 2001 .

[5]  D. Hartley,et al.  Chiral doublet structures in odd-odd n = 75 isotones: chiral vibrations. , 2001, Physical review letters.

[6]  E. Paul,et al.  Smooth band termination in odd mass La nuclei: 127,129,131La , 2000 .

[7]  C. M. Parry,et al.  First evidence for smooth band termination in valence space in the mass 130 region: Spectroscopy of127La , 2000 .

[8]  I. Ragnarsson,et al.  Termination of rotational bands: disappearance of quantum many-body collectivity , 1999 .

[9]  D. Hartley,et al.  Rotational structures in 125La and alignments in A~130 nuclei , 1999 .

[10]  J. Simpson,et al.  competition between collective and terminating structures at very high-spin , 1998 .

[11]  C. M. Parry,et al.  Decreasing Collectivity in Smoothly Terminating Bands in the A ~ 110 Region , 1998 .

[12]  M. R. Maier,et al.  “The microball” Design, instrumentation and response characteristics of a 4π-multidetector exit channel-selection device for spectroscopic and reaction mechanism studies with Gammasphere , 1996 .

[13]  I. Ragnarsson,et al.  The coexistence of the intruder vi132, superdeformed and terminating bands in the A ∼ 135 mass region , 1996 .

[14]  R. Janssens,et al.  New Physics Opportunities at Gammasphere , 1996 .

[15]  Paul,et al.  Band structure of the odd-even 125La, 127La nuclei. , 1996, Physical review. C, Nuclear physics.

[16]  I. Ragnarsson,et al.  Gradual loss of collectivity in rotational bands in the A ∼ 110 (Z ⩾ 50, N ∼ 60) mass region , 1995 .

[17]  D. C. Radford,et al.  ESCL8R and LEVIT8R: Software for interactive graphical analysis of HPGe coincidence data sets , 1995 .

[18]  J. Nyberg,et al.  Alignment processes in 119Cs, 121Cs and 123Cs , 1992 .

[19]  Liang,et al.  Spectroscopy of 123Cs: Configuration dependent crossing frequencies. , 1992, Physical review. C, Nuclear physics.

[20]  Courtney,et al.  Prolate and oblate band structures in odd-odd 186,188Au. , 1992, Physical review. C, Nuclear physics.

[21]  Liang,et al.  Alignment effects in odd-mass Cs isotopes: Spectroscopy of 125Cs. , 1991, Physical review. C, Nuclear physics.

[22]  N. Shinohara,et al.  Level Scheme of 123Ba Fed by the 123La Decay , 1991 .

[23]  H. R. Andrews,et al.  Gamma-ray spectroscopy of 126Ba , 1991 .

[24]  H. R. Andrews,et al.  Rotational bands and shape changes in 124Ba , 1990 .

[25]  J. Nyberg,et al.  Spectroscopy of 123La and configuration dependent proton pairing , 1989 .

[26]  W. Nazarewicz,et al.  Highly deformed intruder bands in the A≈130 mass region , 1988 .

[27]  F. Dönau Electromagnetic radiation of rotating nuclei , 1987 .

[28]  Paul,et al.  Collective oblate band in 131La due to the rotational alignment of h11/2 neutrons. , 1987, Physical review letters.

[29]  S. Frauendorf,et al.  Quasiparticle levels in rotating rare earth nuclei: A cranked shell-model dictionary , 1986 .

[30]  M. Diebel Influence of quadrupole pairing on rotational band-head energies, moments of inertia and band-crossing frequencies , 1984 .

[31]  I. Ragnarsson,et al.  Shape Changes, Band Crossings and Band Terminations in the Very High Spin Region of A = 150-160 Nuclei , 1983 .

[32]  S. Frauendorf Magnetic moments in the backbending region , 1981 .

[33]  S. Frauendorf,et al.  Quasiparticle spectra near the yrast line , 1979 .

[34]  S. Frauendorf,et al.  An interpretation of backbending in terms of the crossing of the ground state band with an aligned two-quasiparticle band , 1979 .

[35]  S. M. Harris Higher Order Corrections to the Cranking Model , 1965 .