Investigation of the fusion reaction 27Al+236U→263105 at excitation energies of 57 MeV and 65 MeV

The energy states for the J , b , ɤ bands and electromagnetic transitions B (E2) values for even – even molybdenum 90 – 94 Mo nuclei are calculated in the present work of "the interacting boson model (IBM-1)" . The parameters of the equation of IBM-1 Hamiltonian are determined which yield the best excellent suit the experimental energy states . The positive parity of energy states are obtained by using IBS1. for program for even 90 – 94 Mo isotopes with bosons number 5 , 4 and 5 respectively. The" reduced transition probability B(E2)" of these neuclei are calculated and compared with the experimental data . The ratio of the excitation energies of the 41+ to 21+ states ( R4/2) are also calculated . The calculated and experimental (R4/2) values showed that the 90 – 94 Mo nuclei have the vibrational dynamical symmetry U(5). Good agreement was found from comparison between the calculated energy states and electric quadruple probabilities B(E2) transition of the 90–94Mo isotopes with the experimental data .

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Fusion and Breakup Reactions of 17S + 208Pb and 15C + 232ThHalo Nuclei Systems

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v11i2.495 ◽

2015 ◽

Vol 11 (2) ◽

pp. 2972-2978

Author(s):

Fouad A. Majeed ◽

Yousif A. Abdul-Hussien

Keyword(s):

Experimental Data ◽

Cross Section ◽

Fusion Reaction ◽

Fusion Cross Section ◽

Reaction Cross ◽

Recent Experimental Data ◽

Barrier Distribution ◽

Coupled Channel ◽

Total Fusion ◽

Full Quantum

In this study the calculations of the total fusion reaction cross section have been performed for fusion reaction systems 17F + 208Pb and 15C + 232Th which involving halo nuclei by using a semiclassical approach.The semiclassical treatment is comprising the WKB approximation to describe the relative motion between target and projectile nuclei, and Continuum Discretized Coupled Channel (CDCC) method to describe the intrinsic motion for both target and projectile nuclei. For the same of comparsion a full quantum mechanical clacualtions have been preforemd using the (CCFULL) code. Our theorticalrestuls are compared with the full quantum mechaincialcalcuations and with the recent experimental data for the total fusion reaction Â checking the stability of the distancesThe coupled channel calculations of the total fusion cross section Ïƒfus, and the fusion barrier distribution Dfus. The comparsion with experiment proves that the semiclassiacl approach adopted in the present work reproduce the experimental data better that the full quantal mechanical calcautions.Â

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Faculty Opinions recommendation of The cytoplasmic domain of the gamete membrane fusion protein HAP2 targets the protein to the fusion site in Chlamydomonas and regulates the fusion reaction.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.725340224.793505354 ◽

2015 ◽

Author(s):

Gareth Bloomfield

Keyword(s):

Fusion Protein ◽

Membrane Fusion ◽

Fusion Reaction ◽

Cytoplasmic Domain ◽

Membrane Fusion Protein ◽

Fusion Site

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Scaling of P -wave excitation energies in heavy-quark systems

Physical Review D ◽

10.1103/physrevd.98.074026 ◽

2018 ◽

Vol 98 (7) ◽

Cited By ~ 9

Author(s):

Marek Karliner ◽

Jonathan L. Rosner

Keyword(s):

Heavy Quark ◽

P Wave ◽

Wave Excitation ◽

Excitation Energies

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Observation of chiral surface excitons in a topological insulator Bi2Se3

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1813514116 ◽

2019 ◽

Vol 116 (10) ◽

pp. 4006-4011 ◽

Cited By ~ 5

Author(s):

H.-H. Kung ◽

A. P. Goyal ◽

D. L. Maslov ◽

X. Wang ◽

A. Lee ◽

...

Keyword(s):

Polarized Light ◽

Orbit Coupling ◽

Experimental Investigations ◽

Composite Particles ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Excitation Energies ◽

Circularly Polarized Light ◽

Pl Emission ◽

Strong Spin

The protected electron states at the boundaries or on the surfaces of topological insulators (TIs) have been the subject of intense theoretical and experimental investigations. Such states are enforced by very strong spin–orbit interaction in solids composed of heavy elements. Here, we study the composite particles—chiral excitons—formed by the Coulomb attraction between electrons and holes residing on the surface of an archetypical 3D TI,Bi2Se3. Photoluminescence (PL) emission arising due to recombination of excitons in conventional semiconductors is usually unpolarized because of scattering by phonons and other degrees of freedom during exciton thermalization. On the contrary, we observe almost perfectly polarization-preserving PL emission from chiral excitons. We demonstrate that the chiral excitons can be optically oriented with circularly polarized light in a broad range of excitation energies, even when the latter deviate from the (apparent) optical band gap by hundreds of millielectronvolts, and that the orientation remains preserved even at room temperature. Based on the dependences of the PL spectra on the energy and polarization of incident photons, we propose that chiral excitons are made from massive holes and massless (Dirac) electrons, both with chiral spin textures enforced by strong spin–orbit coupling. A theoretical model based on this proposal describes quantitatively the experimental observations. The optical orientation of composite particles, the chiral excitons, emerges as a general result of strong spin–orbit coupling in a 2D electron system. Our findings can potentially expand applications of TIs in photonics and optoelectronics.

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Exploitation of Baird Aromaticity and Clar’s Rule for Tuning the Triplet Energies of Polycyclic Aromatic Hydrocarbons

Chemistry ◽

10.3390/chemistry3020038 ◽

2021 ◽

Vol 3 (2) ◽

pp. 532-549

Author(s):

Felix Plasser

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Excited States ◽

Aromatic Hydrocarbons ◽

Density Functional ◽

Materials Science ◽

Chemical Shifts ◽

Qualitative Description ◽

Triplet States ◽

Excitation Energies ◽

Polycyclic Aromatic

Polycyclic aromatic hydrocarbons (PAH) are a prominent substance class with a variety of applications in molecular materials science. Their electronic properties crucially depend on the bond topology in ways that are often highly non-intuitive. Here, we study, using density functional theory, the triplet states of four biphenylene-derived PAHs finding dramatically different triplet excitation energies for closely related isomeric structures. These differences are rationalised using a qualitative description of Clar sextets and Baird quartets, quantified in terms of nucleus independent chemical shifts, and represented graphically through a recently developed method for visualising chemical shielding tensors (VIST). The results are further interpreted in terms of a 2D rigid rotor model of aromaticity and through an analysis of the natural transition orbitals involved in the triplet excited states showing good consistency between the different viewpoints. We believe that this work constitutes an important step in consolidating these varying viewpoints of electronically excited states.

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