In this paper, we report theoretical electron impact ionization cross sections from threshold to 2000 eV for isocarbonic open chain molecules C4H6, C4H8, C4F6 including their isomers, and closed chain molecules c-C4H8 and c-C4F8. Theoretical formalism employed presently, viz., Complex Scattering Potential-ionization contribution method has been used successfully for a variety of polyatomic molecules. The present ionization calculations are very important since results available for the studied targets are either scarce or none. Our work affords comparison of C4 containing hydrocarbon versus fluorocarbon molecules. Comparisons of the present ionization cross sections are made wherever possible, and new ionization data are also presented.

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The ground-state properties of neutron-rich 106 Nb and its β decay into 106 Mo have been studied using the CARIBU radioactive-ion-beam facility at Argonne National Laboratory. Niobium-106 ions were extracted from a 252 Cf fission source and mass separated before being delivered as low-energy beams to the Canadian Penning Trap, as well as the X-Array and SATURN β-decay-spectroscopy station. The measured 106 Nb ground-state mass excess of −66202.0(13) keV is consistent with a recent measurement but has three times better precision; this work also rules out the existence of a second long-lived, β-decaying state in 106 Nb above 5 keV in excitation energy. The decay half-life of 106 Nb was measured to be 1.097(21) s, which is 8% longer than the adopted value. The level scheme of the decay progeny, 106 Mo, has been expanded up to ≈4 MeV. The distribution of decay strength and considerable population of excited states in 106 Mo of J 3 emphasizes the need to revise the adopted J π = 1 − ground-state spin-parity assignment of 106 Nb; it is more likely to be J 3.

In pair production, particle and antiparticle are generated when energy form mass and mass form dipole and then separation take place in stronger nuclear filed. After the formation of mass, it goes on oscillation and oscillation causes the dipole creation on mass which further goes on separation from each other as and moreover the forces F 32 >>F 31 . These two component play major role for the separation of the masses in oscillation time having frequency (f). Also with the help of size of nucleus and atom we calculate the maximum distance and maximum time for pair production 9.99 x 10 -11 m and 3.33 x 10 -19 s, respectively.