A global study of α\alpha-clusters decay in heavy and superheavy nuclei with half-life and preformation factor

A detailed study of $\alpha$-clusters decay is exhibited by incorporating crucial microscopic nuclear structure information into the estimations of half-life and preformation factor. For the first time, using the k-cross validation approach, two semi-empirical formulas for (i) $\alpha$-decay half-life and (ii) $\alpha$-particle preformation factor, are picked out and subsequently modified by including shell, odd-nucleon blocking, and asymmetry effects along with the usual dependence on $\alpha$-decay energy ($Q_{\alpha}$) and angular momentum of $\alpha$-particle. Both the formulas are fitted for the two different regions separated by neutron number N$=$126, as from the experimental systematics the role of N$=$126 shell closure is found decisive in determining the trends of $Q_{\alpha}$, $\alpha$-decay half-life, and $\alpha$-particle preformation factor. It is found that the inclusion of the above-mentioned degrees of freedom significantly reduces the errors in the estimations when compared with several other similar modified/refitted semi-empirical relations indicating the robustness of the proposed formulas. The predictions of $\alpha$-decay half-life throughout the periodic chart have been made including the unknown territory, future probable decay chain of self-conjugate nucleus $^{112}$Ba terminated on $^{100}$Sn, decay chain of $^{208}$Pa through new isotope $^{204}$Ac as well as decay chains of awaiting superheavy nuclei $^{298}$Og and $^{299}$120.Comment: 13 pages, 7 Figures, Accepted in European Physical Journal A (2024

Two photon annihilation operators and squeezed vacuum

Inverses of the harmonic oscillator creation and annihilation operators by their actions on the number states are introduced. Three of the two photon annihilation operators, viz., a(sup +/-1)a, aa(sup +/-1), and a(sup 2), have normalizable right eigenstates with nonvanishing eigenvalues. The eigenvalue equation of these operators are discussed and their normalized eigenstates are obtained. The Fock state representation in each case separates into two sets of states, one involving only the even number states while the other involving only the odd number states. It is shown that the even set of eigenstates of the operator a(sup +/-1)a is the customary squeezed vacuum S(sigma) O greater than

Two-Proton Radioactivity with 2p halo in light mass nuclei A==18−-34

Two-proton radioactivity with 2p halo is reported theoretically in light mass nuclei A $=$ 18-34. We predict $^{19}$Mg, $^{22}$Si, $^{26}$S, $^{30}$Ar and $^{34}$Ca as promising candidates of ground state 2p-radioactivity with S$_{2p}$ $$ 0. Observation of extended tail of spatial charge density distribution, larger charge radius and study of proton single particle states, Fermi energy and the wave functions indicate 2p halo like structure which supports direct 2p emission. The Coulomb and centrifugal barriers in experimentally identified 2p unbound $^{22}$Si show a quasi-bound state that ensures enough life time for such experimental probes. Our predictions are in good accord with experimental and other theoretical data available so far.Comment: 5 Pages, 5 figure

Localized structures in Kagome lattices

We investigate the existence and stability of gap vortices and multi-pole gap solitons in a Kagome lattice with a defocusing nonlinearity both in a discrete case and in a continuum one with periodic external modulation. In particular, predictions are made based on expansion around a simple and analytically tractable anti-continuum (zero coupling) limit. These predictions are then confirmed for a continuum model of an optically-induced Kagome lattice in a photorefractive crystal obtained by a continuous transformation of a honeycomb lattice

ROLE OF TERMINALIA ARJUNA IN ISCHEMIC HEART DISEASE (HRIDAROGA): A REVIEW

Now days, life is becoming very stressful and fast. As many diseases originate due to this hectic lifestyle. One of the important disease is Hridaroga (Ischemic heart disease), which is responsible for many deaths in early age. In Ayurveda, Hridaroga & their symptoms are described in many textbooks. Management of Hridaroga is also very critical and important. In modern medicine, only expensive interventional procedures are described but on the other hand, Ayurvedic herbs are better, cost effective & good therapeutic option for IHD (Hridaroga). The review emphasizes on various properties of Terminalia arjuna. Many clinical & animal studies on T.arjuna show its effect on ECG changes, LV functions & myocardial ischaemic reperfusion injury-etc. Besides this it also has antiatherosclerotic, anticoagulant, anti-infarction, hypolipidemic & hypotensive properties. So, Ayurvedic drug (T. arjuna) is a better option for the treatment of IHD (Hridaroga) because it can improve the quality of life in individuals & potentially save millions of lives

Chaetotaxy of three nymphal instars of an ischnoceran louse, Aegypoecus perspicuus (Phthiraptera: Insecta)

The present study on three nymphal instars of Aegypoecus perspicuus indicated that these differ from each other not only an size, abdominal segmentation, chitinization but also in the number of setae occurring on head, thorax and abdomen. The study also supplements informations regarding the morphological features and chaetotaxy of three nymphal instars of A. perspicuus, occurring on Neophron percnopterus. The diagnostic features of three nymphal instars have also been discussed