Super heavy nuclei may decay through the different decay modes such as spontaneous fission, ternary fission and cluster decay. There is a need to study the different decay modes such as spontaneous ...fission, ternary fission and cluster decay of super heavy nuclei. We studied the spontaneous fission, ternary fission and cluster decay of predicted isotopes of super heavy nuclei for Z=126 and compared with that of alpha decay. This enables to study the competition between spontaneous fission, ternary fission, cluster decay and alpha decay in the super heavy nuclei of Z=126. The comparison of half lives for different decay modes reveals that alpha decay is having smaller half lives than the other studied decay modes. A detailed study of branching ratio of alpha decay with respect to other decay modes also confirms that alpha decay is most dominant decay mode for the super heavy nuclei 318126, 319126, 320126 and 323–326126 and hence these nuclei can be detected through the alpha decay mode only.
We present a new grid of presupernova models of massive stars extending in mass between 13 and 120 , covering four metallicities (i.e., Fe/H = 0, −1, −2, and −3) and three initial rotation velocities ...(i.e., 0, 150, and 300 km s−1). The explosion has been simulated following three different assumptions in order to show how the yields depend on the remnant mass−initial mass relation. An extended network from H to Bi is fully coupled to the physical evolution of the models. The main results can be summarized as follows. (a) At solar metallicity, the maximum mass exploding as a red supergiant (RSG) is of the order of 17 in the nonrotating case, with the more massive stars exploding as Wolf-Rayet (WR) stars. All rotating models, conversely, explode as WR stars. (b) The interplay between the core He-burning and the H-burning shell, triggered by the rotation-induced instabilities, drives the synthesis of a large primary amount of all the products of CNO, not just . A fraction of them greatly enriches the radiative part of the He core (and is responsible for the large production of F), and a fraction enters the convective core, leading therefore to an important primary neutron flux able to synthesize heavy nuclei up to Pb. (c) In our scenario, remnant masses of the order of those inferred from the first detections of gravitational waves (GW 150914, GW 151226, GW 170104, GW 170814) are predicted at all metallicities for none or moderate initial rotation velocities.
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