Energy Spectrum for a Short-Range 1/r Singular Potential with a Non-Orbital Barrier Using the Asymptotic Iteration Method

Using the asymptotic iteration method, we obtain the S-wave solution for a short-range three-parameter central potential with 1/r singularity and with a non-orbital barrier. To the best of our knowledge, this is the first attempt at calculating the energy spectrum for this potential, which was introduced by H. Bahlouli and A. D. Alhaidari and for which they obtained the “potential parameter spectrum”. Our results are also independently verified using a direct method of diagonalizing the Hamiltonian matrix in the J-matrix basis.

Bi-normalized response spectra and seismic intensity in Bucharest for 1986 and 1990 Vrancea seismic events

The Vrancea subcrustal earthquakes of August 30,1986 and May 30,1990 are the two most recent seismic events that have occurred in Romania with moment magnitudes M W ≥ 6.9.The spectral analysis of the strong ground motions recorded in Bucharest reveals that despite small differences in magnitude between the 1986 and 1990 earthquakes,their frequency contents are very different,sometimes even opposing.The main focus of this study is to conduct a comparative analysis of the response spectra in terms of the bi-normalized response spectra(BNRS) proposed by Xu and Xie(2004 and 2007) for strong ground motions recorded in Bucharest during these two seismic events.The mean absolute acceleration and relative velocity response spectra for the two earthquakes are discussed and compared.Furthermore,the mean bi-normalized absolute acceleration and normalized relative velocity response spectra with respect to the control period T C are computed for the ground motions recorded in Bucharest in 1986 and 1990.The predominant period T P is also used in this study for the normalization of the spectral period axis.Subsequently,the methodology proposed by Martinez-Perreira and Bommer(1998) is applied in order to estimate the seismic intensity of the two events.The results are discussed and several conclusions regarding the possibility of using the bi-normalized response spectra(BNRS) are given.

Potential energy curve study on the ^3Π electronic states of GaX （X=F, Cl, and Br） molecules

The potential energy curves （PECs） of the 3Π states of GaX （X=F, Cl, and Br） molecules are calculated using the multireference configuration interaction method with a large contracted basis set aug-cc-pV5Z. The PECs are accurately fitted to analytical potential energy functions （APEFs） using the Murrell–Sorbie potential function. The spectroscopic parameters for the states are determined using the obtained APEFs, and compared with the theoretical and experimental data available presently in the literature.

Analytical potential energy function and spectroscopy parameters for B^1Π state of KH

Multi-reference configuration interaction is used to produce potential energy curves （PECs） for the excited B1FI state of KH molecule. To investigate the correlation effect of core-valence electrons, five schemes are employed which include the different correlated electrons and different active spaces. The PECs are fitted into analytical potential energy functions （APEFs）. The spectroscopic parameters, ro-vibrational levels, and transition frequencies are determined based on the APEFs and compared with available experimental and theoretical data. The molecular properties for B1II obtained in this letter, which are better than those available in literature, can be reproduced with calculations using the suitable correlated electrons and active space of orbitals.

Analysing the atmospheric-oceanic conditions driving the sustained long track and intensity of Tropical Cyclone Freddy

During February–March 2023,the record-breaking tropical cyclone(TC)Freddy caused widespreadflooding and damages across southeastern Africa.While<5%of TCs make landfall into southern Africa,TC Freddy made landfall twice and is the only TC in the past two decades that has tracked over 8000 km across the entire southern Indian Ocean.To understand why TC Freddy was so unique,this study investigated the evolution,track and atmospheric-oceanic mechanisms driving TC Freddy using the ERA5,CFSv2,OSTIA,NCEP-NCAR datasets and track data from various sources.It was found that SSTs were>27◦C during TC Freddy’s lifetime,while TC Dingani and a split Mascarene High played a role in steering TC Freddy across the southern Indian Ocean.Leading up to the development of TC Freddy,conditions were favourable for TC genesis,as indicated by the levels of the Genesis Potential Parameter(GPP)and its modified version(GPPI),the tropical cyclone heat potential levels,and elevated SSTs.Ridging subtropical anticyclones and the Mascarene High alongside favourable steeringflow and GPP(and GPPI)conditions resulted in Freddy’s double landfall in Mozambique.In assessing the tracks,it was found that there are discrepancies in the track of the commonly used IBTrACS when compared to ERA5 and RSMC tracks,which has implications for impact studies due to the underestimation of landfall considerations.This study reveals the unique characteristics and atmospheric-oceanic mechanisms driving TC Freddy,emphasising the impor-tance of accurate representation of favourable conditions and track data for enhancing TC forecasting and impact assessments.