Identification of excited states in Os-167 and Os-168 : shape coexistence at extreme neutron deficiency

• Excited states in the very neutron-deficient isotopes Os-167 and Os-168 have been observed using the reaction Sn-112(Ni-58, 2pxn). The JUROSPHERE gamma -ray spectrometer array was used in conjunction with the RITU gas-filled recoil separator to collect prompt gamma radiation in coincidence with recoils implanted in a silicon strip detector located at the focal plane of RITU. Using a selective recoil decay tagging technique it has been possible to unambiguously assign gamma -ray transitions to Os-167 and Os-168 through the characteristic a radioactivity of these nuclides. The high-spin structure of the bands is discussed in terms of quasiparticle configurations within the framework of the cranked shell model. The role of shape coexistence in Os-168 is examined with phenomenological three-band mixing calculations.

Subject headings

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Keyword

Sn-112 (Ni-58

2p)

(Ni-58

n2p)

E=266 MeV

measured E gamma

I gamma-

gamma gamma-coincidence

Os-167.168 deduced high-spin levels

J

pi

configurations

shape coexistence

jurosphere spectrometer

gas-filled separator

cranked mean-field calculations

gamma-ray spectroscopy

rare-earth nuclei

high-spin

hg isotopes

yrast line

band

alignment

decay

even

Publication and Content Type

ref (subject category)

art (subject category)