Orateur
Description
The tungsten isotopes 165W and 169W have been studied by using fusion-evaporation reactions $^{92}$Mo($^{78}$Kr,4p1n)$^{165}$W and $^{92}$Mo($^{84}$Kr,1α2p1n)$^{169}$W at the Accelerator laboratory of the University of Jyväskylä, Finland. Beam energies of 380 and 402 MeV were used for the $^{165}$W and $^{169}$W experiments, respectively. The vacuum-mode separator MARA [1], the JUROGAM 3 germanium-detector array [2], and the MARA focal-plane detector setup [3] were utilised to select the reaction channels of interest and determine energies and half-lives for the previously unknown isomeric state properties. The structure above these 13/2$^+$ isomers is relatively well known in both nuclei [4,5], allowing us to use the in-beam gamma rays in addition to mass and X-ray information to identify the isomeric transitions observed at the focal plane. The new results and systematics of isomerism in tungsten isotopes will be discussed.
[1] J. Uusitalo et al., Acta Phys. Pol. B 50 (2019) 319-327.
[2] J. Pakarinen et al., Eur. Phys. J. 56 (2020) 149.
[3] J. Sarén et al., Nucl. Instrum. Methods Phys. Res. B 541 (2023) 33-36.
[4] J. Simpson et al., J. Phys. G 18 (1992) 1207-1225.
[5] J. Recht et al., Nucl. Phys. A 440 (1985) 366-396.
