Binary black hole coalescence in the large-mass-ratio limit: the hyperboloidal layer method and waveforms at null infinity

We compute and analyze the gravitational waveform emitted to future null infinity by a system of two black holes in the large mass ratio limit. We consider the transition from the quasi-adiabatic inspiral to plunge, merger, and ringdown. The relative dynamics is driven by a leading order in the mass ratio, 5PN-resummed, effective-one-body (EOB), analytic radiation reaction. To compute the waveforms we solve the Regge-Wheeler-Zerilli equations in the time-domain on a spacelike foliation which coincides with the standard Schwarzschild foliation in the region including the motion of the small black hole, and is globally hyperboloidal, allowing us to include future null infinity in the computational domain by compactification. This method is called the hyperboloidal layer method, and is discussed here for the first time in a study of the gravitational radiation emitted by black hole binaries. We consider binaries characterized by five mass ratios, $\nu=10^{-2,-3,-4,-5,-6}$, that are primary targets of space-based or third-generation gravitational wave detectors. We show significative phase differences between finite-radius and null-infinity waveforms. We test, in our context, the reliability of the extrapolation procedure routinely applied to numerical relativity waveforms. We present an updated calculation of the gravitational recoil imparted to the merger remnant by the gravitational wave emission. As a self consistency test of the method, we show an excellent fractional agreement (even during the plunge) between the 5PN EOB-resummed mechanical angular momentum loss and the gravitational wave angular momentum flux computed at null infinity. New results concerning the radiation emitted from unstable circular orbits are also presented.Comment: 22 pages, 18 figures. Typos corrected. To appear in Phys. Rev.

Dynamical vs. Auxiliary Fields in Gravitational Waves around a Black Hole

The auxiliary/dynamic decoupling method of hep-th/0609001 applies to perturbations of any co-homogeneity 1 background (such as a spherically symmetric space-time or a homogeneous cosmology). Here it is applied to compute the perturbations around a Schwarzschild black hole in an arbitrary dimension. The method provides a clear insight for the existence of master equations. The computation is straightforward, coincides with previous results of Regge-Wheeler, Zerilli and Kodama-Ishibashi but does not require any ingenuity in either the definition of variables or in fixing the gauge. We note that the method's emergent master fields are canonically conjugate to the standard ones. In addition, our action approach yields the auxiliary sectors.Comment: 26 page

Tying Community Engagement With Appropriate Technology At The Last Mile: A Cluster Randomized Trial To Determine The Effectiveness Of A Novel, Digital Pendant And Voice Reminder Platform On Increasing Infant Immunization Adherence Among Mothers In Rural Udaipur, India

Background: 500,000 children under the age of five die from vaccine preventable diseases in India every year. More than just improving coverage, increasing timeliness of immunizations is critical to ensuring infant health in the first year of life. Novel, culturally-appropriate, community engagement strategies are worth exploring to close the immunization gap. In this case, a digital pendant and voice call reminder (components of the Khushi Baby platform) are tested for the effectiveness in improving DTP3 adherence within two monthly camps from DTP1 administration. Methodology: A cluster randomized trial was conducted in which 96 village health camps were randomized to three arms: NFC sticker, NFC pendant, and NFC pendant with voice call reminder in local dialect across 5 blocks in the Udaipur District serviced by Seva Mandir from August 2015 to April 2016. Results: The pendant and pendant with voice call reminder arms did not significantly improve adherence compared to the sticker group. Point estimates suggested that there was a higher odds of on-time completion in the pendant with voice call group compared to both the pendant group and the sticker group. Conclusions: Despite the null results for adherence, the fact that the pendant was well retained and well accepted by the community suggests that the pendant can be a valuable social symbol and community engagement tool. Low power and short term follow-up may have masked true effects of the system. A larger randomized trial slated to begin in August 2016 will look to replicate and build off the study findings in the Udaipur district

Gender and irrigation in India: The Women's Irrigation Group of Jambar, South Gujarat

Irrigation management / Women in development / Gender / Female labor / Agricultural credit / Decision making / Irrigation programs / Rain-fed farming / Institution building / Pumping

Does the social status of the elderly impact morbidities among them? – A cross sectional Study in a district of Gujarat

Background: The aging population is both medical & sociological problem for the country and they suffer with high rates of morbidity and mortality. So Social factors lay a significant impact on the health practices and this study will help us to understand and evaluate their health problems of elderly. Aims and Objective: 1. To assess the social status of elderly population. 2. To associate the findings with morbidities of elderly Methods: A cross sectional study was carried out in urban and rural area of Surendranagar district among 611 elderly, using a predesigned and pre tested questionnaire by directly questioning the subjects with oral and written consent. For selection of the area, in both areas, the sampling units were enumerated and samples were collected by using simple random sampling, data was entered and analyzed using MS excel 2007. Result: Nearly 60 % of the subjects were currently unemployed and the predominant family system was 3 generation family. Majority of the families in the urban areas were from social class 4, whereas in the rural areas were from social class 5. Having poor social score had a statistically significant association with presence of morbidity in elderly both areas. Conclusions: Majority of elderly in both urban and rural areas had a poor social status. Role of the family and social structure on the health of the elderly can be clearly established. However, support structure must be developed in our social system in a way that the destitute and dependent elderly are taken care of by either government system or social organizations like NGOs and old age home

Binary black hole merger in the extreme mass ratio limit

We discuss the transition from quasi-circular inspiral to plunge of a system of two nonrotating black holes of masses $m_1$ and $m_2$ in the extreme mass ratio limit $m_1m_2\ll (m_1+m_2)^2$. In the spirit of the Effective One Body (EOB) approach to the general relativistic dynamics of binary systems, the dynamics of the two black hole system is represented in terms of an effective particle of mass $\mu\equiv m_1m_2/(m_1+m_2)$ moving in a (quasi-)Schwarzschild background of mass $M\equiv m_1+m_2$ and submitted to an ${\cal O}(\mu)$ radiation reaction force defined by Pad\'e resumming high-order Post-Newtonian results. We then complete this approach by numerically computing, \`a la Regge-Wheeler-Zerilli, the gravitational radiation emitted by such a particle. Several tests of the numerical procedure are presented. We focus on gravitational waveforms and the related energy and angular momentum losses. We view this work as a contribution to the matching between analytical and numerical methods within an EOB-type framework.Comment: 14 pages, six figures. Revised version. To appear in the CQG special issue based around New Frontiers in Numerical Relativity conference, Golm (Germany), July 17-21 200

A Chandra X-Ray Survey of Ultraluminous Infrared Galaxies

We present results from Chandra observations of 14 ultraluminous infrared galaxies (ULIRGs; log(L_IR/L_Sun) >= 12) with redshifts between 0.04 and 0.16. The goals of the observations were to investigate any correlation between infrared color or luminosity and the properties of the X-ray emission and to attempt to determine whether these objects are powered by starbursts or active galactic nuclei (AGNs). The sample contains approximately the same number of high and low luminosity objects and ``warm'' and ``cool'' ULIRGs. All 14 galaxies were detected by Chandra. Our analysis shows that the X-ray emission of the two Seyfert 1 galaxies in our sample are dominated by AGN. The remaining 12 sources are too faint for conventional spectral fitting to be applicable. Hardness ratios were used to estimate the spectral properties of these faint sources. The photon indices for our sample plus the Chandra-observed sample from Ptak et al.(2003) peak in the range of 1.0-1.5, consistent with expectations for X-ray binaries in a starburst, an absorbed AGN, or hot bremsstrahlung from a starburst or AGN. The values of photon index for the objects in our sample classified as Seyferts (type 1 or 2) are larger than 2, while those classified as HII regions or LINERs tend to be less than 2. The hard X-ray to far-infrared ratios for the 12 weak sources are similar to those of starbursts, but we cannot rule out the possibility of absorbed, possibly Compton-thick, AGNs in some of these objects. Two of these faint sources were found to have X-ray counterparts to their double optical and infrared nuclei.Comment: 40 pages, 5 tables, 14 figures, accepted by Ap

Condensation transition in a model with attractive particles and non-local hops

We study a one dimensional nonequilibrium lattice model with competing features of particle attraction and non-local hops. The system is similar to a zero range process (ZRP) with attractive particles but the particles can make both local and non-local hops. The length of the non-local hop is dependent on the occupancy of the chosen site and its probability is given by the parameter $p$. Our numerical results show that the system undergoes a phase transition from a condensate phase to a homogeneous density phase as $p$ is increased beyond a critical value $p_c$. A mean-field approximation does not predict a phase transition and describes only the condensate phase. We provide heuristic arguments for understanding the numerical results.Comment: 11 Pages, 6 Figures. Published in Journal of Statistical Mechanics: Theory and Experimen

Applications of Signed Graphs to Portfolio Turnover Analysis

AbstractPortfolio turnover is an important area for portfolio managers and investors, since it significantly impacts returns through higher trading costs and taxes. Currently, methods for assessing the possibility of portfolio turnover are practically non-existent. Using the concept of signed graphs one can assess the stability of portfolios and thereby the likelihood of portfolio turnover. We demonstrate our method using empirical data from the Indian Stock Exchange and show that portfolios focusing on risk alone can result in higher portfolio turnover, causing misleading portfolio management

On the Propagation of Shock Waves Produced by Explosion of a Spherical Charge in Deep Sea

The propagation of spherical shock waves, produced by explosion of a spherical charge in deep sea, have been studied using the, energy hypothesis of T.Y. Thomas. The energy release from the charge is supposed to be time dependent and the effects of earth's gravitation is taken into account. It is found that the shock compression varies very slowly with variation in the direction of shock propagation. The effects of earth's gravitation is to decrease the shock compression and its decay with shock radius. A comparison has also been made between the results of time dependent and instantaneous energy release