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In this work, we extend the analytic treatment of Bessel functions of large order and/or argument. We examine uniform asymptotic Bessel function expansions and show their accuracy and range of validity. Such situations arise in a variety of applications, particularly the Fourier transform (FT) of the gravitational wave (GW) signal from a pulsar, global parameter space correlations of a coherent matched filtering search for continuous GWs from isolated neutron stars and tomographic reconstruction of GW LISA sources. The uniform expansion we consider here is found to be valid in the entire range of the argument.

Effective one body numerical relativity waveform models for spin-aligned binary black holes (SEOBNR) are based on the effective one body theoretical framework and numerical relativity simulation results. SEOBNR models have evolved through version 1 to version 4. We recently extended SEOBNRv1 model to SEOBNRE (Effective One Body Numerical Relativity waveform models for Spin-aligned binary black holes along Eccentric orbit) model which is also valid for spin-aligned binary black hole coalescence along eccentric orbit. In this paper, we update our previous SEOBNRE model to make it consistent to SEOBNRv4 which is the most widely used SEOBNR waveform model. This upgraded SEOBNRE model improves accuracy compared to previous SEOBNRE model, especially for highly spinning black holes. For spin-aligned binary black holes with mass ratio $1\le q\lesssim 10$, dimensionless spin $-0.9\lesssim \chi \lesssim 0.995$ and orbital eccentricity $0\le e_0\lesssim 0.6$ at reference frequency $M{f}_0=0.002$ ($M$ is the total mass of the binary black hole, $f_0\approx 40\frac{10{\mathrm{\text{M}}}_{\odot }}{M}$Hz), the upgraded SEOBNRE model can always fit numerical relativity waveform better than 98.2%. For most cases, the fitting factor can even be better than 99%.

Prediction of ribonucleic acid (RNA) secondary structure is an important task in bioinformatics. The RNA structure is known to influence its biological functionality. RNA secondary structure contains many substructures such as stems, loops and pseudoknots. The substructure pseudoknot occurs in several classes of RNAs, and plays a vital role in many biological processes. Prediction of pseudoknots in RNA is challenging and still an open research problem. Several computational methods based on dynamic programming, genetic algorithms, statistical models, etc., have been proposed with varying success. In this paper, we employ matched filtering approach to determine the RNA secondary structure containing pseudoknots. The central idea is to use a matched filter to identify the longest possible stem patterns in the base-pairing matrix of an RNA. The stem patterns obtained are then used to determine the locations of the other substructures such as loops and pseudoknots present in the RNA. Comparison of the prediction results, for RNA sequences derived from PseudoBase, illustrate the effectiveness and the accuracy of our proposed approach as compared to some of the existing popular RNA secondary structure prediction methods.

Core-collapse supernovae are a diverse population with energetic broad-line events, that include their off-spring in ultra-relativistic gamma-ray bursts and a recently discovered highly superluminous event ASASSN-15L (SN2015L). They may be associated with the formation of black holes, rather than magnetars, by their ample baryon-poor energy reservoir in angular momentum desribed by the Kerr metric. Black holes formed herein evolve through various phases that may include direct accretion, Bardeen accretion and spin down to slow rotation, down to a dimensionless spin parameter 0.36 defined by a fixed point in equations of suspended accretion. Evidence may come from gravitational wave emission from associated non-axisymmetric accretion flows, especially from high density matter at the Inner Most Stable Circular Orbit (ISCO) during the latter phase of spin down. We here present a chirp-based spectrogram based on a recently developed “butterfly” filter to probe nearby events by LIGO-Virgo and KAGRA for ascending and descending chirps, making use of embarrassingly parallel computing. Included is a demonstration on the nearby SN2010br Type Ibc (D ≃ 12 Mpc) event covered by LIGO S6. Comments on the recently discovered GWB150914 are included.