Radial infall of two compact objects: 2.5PN linear momentum flux and associated recoil

The loss rate of linear momentum from a binary system composed of compact objects (radially falling towards each other under mutual gravitational influence) has been investigated using the multipolar post-Minkowskian approach. The 2.5PN accurate analytical formula for the linear momentum flux is provided, in terms of the separation of the two objects, in harmonic coordinates, both for a finite and infinite initial separation. The 2.5PN formulas for the linear momentum flux are finally used to estimate the recoil velocity accumulated during a premerger phase of the binary evolution.Comment: 17 pages, 2 figure

Accurate inspiral-merger-ringdown gravitational waveforms for non-spinning black-hole binaries including the effect of subdominant modes

We present an analytical waveform family describing gravitational waves (GWs) from the inspiral, merger and ringdown of non-spinning black-hole binaries including the effect of several non-quadrupole modes [($\ell = 2, m = \pm 1), (\ell = 3, m = \pm 3), (\ell = 4, m = \pm 4)$ apart from $(\ell = 2, m=\pm2)$]. We first construct spin-weighted spherical harmonics modes of hybrid waveforms by matching numerical-relativity simulations (with mass ratio $1-10$) describing the late inspiral, merger and ringdown of the binary with post-Newtonian/effective-one-body waveforms describing the early inspiral. An analytical waveform family is constructed in frequency domain by modeling the Fourier transform of the hybrid waveforms making use of analytical functions inspired by perturbative calculations. The resulting highly accurate, ready-to-use waveforms are highly faithful (unfaithfulness $\simeq 10^{-4} - 10^{-2}$) for observation of GWs from non-spinning black hole binaries and are extremely inexpensive to generate.Comment: 10 pages, 5 figure

Ready-to-use post-Newtonian gravitational waveforms for binary black holes with non-precessing spins: An update

For black-hole binaries whose spins are (anti-) aligned with respect to the orbital angular momentum of the binary, we compute the frequency domain phasing coefficients including the quadratic-in-spin terms up to the third post-Newtonian (3PN) order, the cubic-in-spin terms at the leading order, 3.5PN, and the spin-orbit effects up to the 4PN order. In addition, we obtain the 2PN spin contributions to the amplitude of the frequency-domain gravitational waveforms for non-precessing binaries, using recently derived expressions for the time-domain polarization amplitudes of binaries with generic spins, complete at that accuracy level. These two results are updates to Arun et al. (2009) [1] for amplitude and Wade et al. (2013) [2] for phasing. They should be useful to construct banks of templates that model accurately non-precessing inspiraling binaries, for parameter estimation studies, and or constructing analytical template families that accounts for the inspiral-merger-ringdown phases of the binary.Comment: 8 pages, an additional file (readable in MATHEMATICA) containing all the key results included in the sourc

Gravitational-wave phasing for low-eccentricity inspiralling compact binaries to 3PN order

[abridged] Although gravitational radiation causes inspiralling compact binaries to circularize, a variety of astrophysical scenarios suggest that binaries might have small but nonnegligible orbital eccentricities when they enter the low-frequency bands of ground and space-based gravitational-wave detectors. If not accounted for, even a small orbital eccentricity can cause a potentially significant systematic error in the mass parameters of an inspiralling binary. Gravitational-wave search templates typically rely on the quasi-circular approximation, which provides relatively simple expressions for the gravitational-wave phase to 3.5 post-Newtonian (PN) order. The quasi-Keplerian formalism provides an elegant but complex description of the post-Newtonian corrections to the orbits and waveforms of inspiralling binaries with any eccentricity. Here we specialize the quasi-Keplerian formalism to binaries with low eccentricity. In this limit the non-periodic contribution to the gravitational-wave phasing can be expressed explicitly as simple functions of frequency or time, with little additional complexity beyond the well-known formulas for circular binaries. These eccentric phase corrections are computed to 3PN order and to leading order in the eccentricity for the standard PN approximants. For a variety of systems these eccentricity corrections cause significant corrections to the number of gravitational wave cycles that sweep through a detector's frequency band. This is evaluated using several measures, including a modification of the useful cycles. We also evaluate the role of periodic terms that enter the phasing and discuss how they can be incorporated into some of the PN approximants. While the eccentric extension of the PN approximants is our main objective, this work collects a variety of results that may be of interest to others modeling eccentric relativistic binaries.Comment: 49 pages, 4 figures. Submitted to Phys. Rev. D. Supplementary materials available at http://link.aps.org/supplemental/10.1103/PhysRevD.93.124061. V2: minor updates to match published versio

Antecedent and Sequalae Issues of Nepalese Women Trafficked into Prostitution

Using a qualitative descriptive methodology, this study explored the experiences of Nepalese women trafficked into prostitution in India. The study found that poverty and lack of awareness about being at risk for trafficking are the major precursors for their trafficking experience. Abduction, fake marriages and the seduction of a better job were the major approaches adopted by pimps to traffic the women. The study also showed that after returning from the Indian brothel(s), they were rejected by their family and community. Such rejections occurred as family and community perceived these young women as at high risk for HIV infection. Strategies should be put in place to assist the women to reintegrate into their family and community

Spin effects in Spherical Harmonic Modes of Gravitational Waves from Eccentric Compact Binary Inspirals

We compute the leading and sub-leading spin effects through the second post-Newtonian order (2PN) in spherical harmonic modes of gravitational waveforms from inspiralling compact binaries in non-circular orbits with non-precessing components. The two spin couplings, linear-in-spin (spin-orbit; SO) and quadratic-in-spin (spin-spin; SS), that appear in 2PN waveforms are computed with desired accuracy and explicit expressions for relevant modes are derived. The modes that have spin corrections through 2PN include $(\ell, |m|)$=$((2,2),\,(2,1),\,(3,3),\,(3,2),\,(3,1),\,(4,3),\,(4,1))$ modes. Closed form expressions for these modes for compact binaries in general orbits as well as in elliptical orbits are being provided. While the general orbit results can be used to study signals from binaries in orbits of arbitrary shape and nature, elliptical orbit results are applicable to systems with arbitrary eccentricities. We also express the elliptical orbit results as leading eccentric corrections to the circular results. Our prescription represents, the first, fully analytical treatment that combines spins, eccentricity and higher modes together and completes computation of spin effects through 2PN order. These should find immediate applications in inspiral-merger-ringdown modelling for eccentric mergers including the effect of non-precessing spins and higher modes as well as in parameter estimation analyses employing inspiral waveform

OPTIMIZATION OF CULTURE PARAMETERS FOR α-GLUCOSIDASE PRODUCTION FROM PROTONEMAL BIOMASS OF BRYUM CORONATUM SCHWAEGR

Objective: The purpose of the present investigation was to optimization of culture parameters for α-glucosidase production from protonemal biomass of Bryum coronatum Schwaegr.Methods: Fresh unopened, mature capsules were used as explant and the protonema that developed from the aseptic spores were cultured grown on 1/4th Murashige and Skoog basal medium. Frozen protonemal biomass was homogenized in 100 mM phosphate buffer (pH 7.0). The supernatant was assayed for α-glucosidase activity. Various culture parameters such as incubation period, temperature, pH, agitation, carbon sources and nitrogen sources were evaluated and further Taguchi orthogonal array method was performed.Results: It was observed that both protonemal biomass and α-glucosidase production were maximum at 28 d of culture. Optimization of culture parameters such as pH, temperature and agitation speed for α-glucosidase production was found to be 6.0, 35 °C and 150 rpm, respectively. Among nutritional parameters, sucrose as carbon source and ammonium nitrate as nitrogen source found to be effective for enzyme production and maximum growth of protonemal biomass of B. coronatum. Based on Taguchi orthogonal array method, the optimal condition and their contribution on α-glucosidase production were evaluated as follows: sucrose (1.5%), ammonium nitrate (1%), pH (6.0), temperature (35 °C) and agitation (150 rpm).Conclusion: In this study, the culture of moss, B. coronatum proved to be a good source for the enzyme α-glucosidase production. Temperature 35 °C and pH 6.0 were found to be optimum for maximum α-glucosidase production with respect to protonemal biomass production. Optimization of culture medium by Taguchi method has resulted in an increase in the α-glucosidase activity from 3.84-14.39 U/ml.Â

IN VITRO CULTURE OF MOSS BRYUM CORONATUM SCHWAEGR.(BRYACEAE) AND IT'S PHYTOCHEMICAL ANALYSIS

Objective: The purpose of the present investigation was to establish in vitro conditions for moss Bryum coronatum Schwaegr. And to carry out preliminary phytochemical screening of B. coronatum leaf extracts in different solvents. Methods: Fresh unopened, mature capsules were used as explant and surface sterilization of spores bearing capsule with different concentration of sodium hypochlorite (0.5, 1, 2, 4 and 8%) with different time duration. The Mu­rashige and Skoog (MS) medium that contains different concentration(full,1/2, 1/4th, 1/8th strength) with different concentration of sucrose were used for culture this moss. Phytochemical screening were carried out using ethanol, methanol and ethyl acetate leaf extract of B. coronatum to identify various constitutes using the standard procedures. Results: Surface sterilization of spores of this moss was most effective in 4% commercial bleach for 1 min sterilization. The optimum condition for germination of spores and for proper growth of gametophytes B. coronatum on MS/4 medium strength with sucrose (1.5%), at pH 5.8 and temperature 22±2ºC with 16/8h: light/dark condition. Phytochemical analyses revealed the presence of alkaloids, terpenoids and saponins in all extracts. Conclusion: Four percentage NaOCl aqueous solutions are better for surface sterilization of moss sporophytes. MS/4 medium with 1.5% sucrose found the best medium for spore germination. Solvents extracts showed presence of alkaloids, terpenoids and saponins in all extracts