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

Learning from the Experiences of Collegiate Athletes Living through a Season- or Career-Ending Injury

An athlete’s identity is often related to the goals of their team and their ability to achieve excellence in sport. A threat to an athlete’s identity is a season- or career-ending injury. Athletes can respond to season- or career-ending injuries in ways detrimental to their psychosocial well-being (Ivarsson, Tranaeus, Johnson, & Stenling 2017). This study built upon existing knowledge by seeking to better understand the lived experiences of Division I collegiate athletes who experienced a season- or career-ending injury. There is a need for ongoing recommendations for helping athletes process their injuries. Researchers used a descriptive phenomenological approach. Researchers interviewed ten college athletes who experienced a season- or career-ending injury. Themes included: (1) physical and emotional stress, (2) resistance to resiliency, (3) importance of relationships with others, and (4) appreciation and cultivation for new possibilities outside of sport. This research provided insight for behavioral health professionals on injury response. This included the need for Posttraumatic Growth responses such as (1) building strong support pre- and post-injury, (2) recognizing healthy coping mechanisms, (3) cultivating new identities for athletes, (4) helping an athlete with identity loss, (5) helping athletes recognize new possibilities post-injury, and (6) helping an athlete maintain an appreciation for life

The Challenge of Integrating Renewable Generation in the Alberta Electricity Market

Renewable electric generation is forecast to enjoy an increasing share of total capacity and supply regimes in the future. Alberta is no exception to this trend, having initiated policy incentives in response to calls for increasing the fraction of wind and solar energy available to the province over the next decade.1 This call is coming from various sectors including advocacy groups, the provincial government and some utilities. The University of Calgary’s School of Public Policy convened a roundtable discussion on Sept. 15, 2015. Given the wide-ranging aspects of increased renewables integration (for example the policy options, economic forces and engineering/technical issues) the topic demands attention from a wide range of experts and stakeholders. To that end, we endeavoured to group expert panellists and representatives of utilities, public agencies, academe and consumer groups to consider the planning necessary to integrate new renewable capacity into the existing and future grid system in the province and its potential impact. The purpose of the roundtable was to facilitate and foster a knowledge exchange between interested and knowledgeable parties while also aggregating this knowledge into a more complete picture of the challenges and potential strategies associated with increased renewables integration in the Alberta electricity grid

Anna Colleen Coleman in a Senior Voice Recital

This is the program for the senior voice recital of Anna Colleen Coleman, accompanied by Rebecca Moore on piano, Shayla Blake on flute, and soprano Shelley Smith. The recital was held on April 22, 1996, in the McBeth Recital Hall in the Mabee Fine Arts Center

What's the best treatment for sebaceous cysts?

Punch biopsy excision appears to be superior to traditional wide elliptical excision for the treatment of sebaceous cysts when intervention is necessary (strength of recommendation [SOR]: B, based on 1 small randomized study). No rigorous metho- dological studies have compared punch biopsy excision of sebaceous cysts with the minimal excision technique

Training That Works: Lessons from California\u27s Employment Training Panel Program

The authors provide an in-depth analysis of an incumbent worker training program funded through California\u27s unemployment insurance taxes.https://research.upjohn.org/up_press/1052/thumbnail.jp