Carbon Dioxide in Exoplanetary Atmospheres: Rarely Dominant Compared to Carbon Monoxide and Water in Hot, Hydrogen-dominated Atmospheres

We present a comprehensive study of the abundance of carbon dioxide in exoplanetary atmospheres in hot, hydrogen-dominated atmospheres. We construct novel analytical models of systems in chemical equilibrium that include carbon monoxide, carbon dioxide, water, methane and acetylene and relate the equilibrium constants of the chemical reactions to temperature and pressure via the tabulated Gibbs free energies. We prove that such chemical systems may be described by a quintic equation for the mixing ratio of methane. By examining the abundances of these molecules across a broad range of temperatures (spanning equilibrium temperatures from 600 to 2500 K), pressures (via temperature-pressure profiles that explore albedo and opacity variations) and carbon-to-oxygen ratios, we conclude that carbon dioxide is subdominant compared to carbon monoxide and water. Atmospheric mixing does not alter this conclusion if carbon dioxide is subdominant everywhere in the atmosphere. Carbon dioxide and carbon monoxide may attain comparable abundances if the metallicity is greatly enhanced, but this property is negated by temperatures above 1000 K. For hydrogen-dominated atmospheres, our generic result has the implication that retrieval studies may wish to set the subdominance of carbon dioxide as a prior of the calculation and not let its abundance completely roam free as a fitting parameter, because it directly affects the inferred value of the carbon-to-oxygen ratio and may produce unphysical conclusions. We discuss the relevance of these implications for the hot Jupiter WASP-12b and suggest that some of the previous results are chemically impossible. The relative abundance of carbon dioxide to acetylene is potentially a sensitive diagnostic of the carbon-to-oxygen ratio.Comment: Accepted by ApJ. 12 pages, 8 figures, 2 table

Column: Evaluation of Interprofessional Education Programs

In this brief space, I would like to provide some general guidelines for those of you who are planning to implement an interprofessional education program, or any program for that matter. I say planning to implement a program, because it is at this stage that you must be thinking about how you are going to evaluate it, not after the program has begun. One of the worst nightmares for any program evaluator is to have someone stop by his or her office with a stack of data and say “Can you tell me what I have here?” When this happens it is often extremely difficult to extract meaningful conclusions about the project. Therefore, it is critical to build your evaluation plan into your project plan

Atmospheric Chemistry for Astrophysicists: A Self-consistent Formalism and Analytical Solutions for Arbitrary C/O

We present a self-consistent formalism for computing and understanding the atmospheric chemistry of exoplanets from the viewpoint of an astrophysicist. Starting from the first law of thermodynamics, we demonstrate that the van't Hoff equation (which describes the equilibrium constant), Arrhenius equation (which describes the rate coefficients) and procedures associated with the Gibbs free energy (minimisation, rescaling) have a common physical and mathematical origin. We address an ambiguity associated with the equilibrium constant, which is used to relate the forward and reverse rate coefficients, and restate its two definitions. By necessity, one of the equilibrium constants must be dimensionless and equate to an exponential function involving the Gibbs free energy, while the other is a ratio of rate coefficients and must therefore possess physical units. We demonstrate that the Arrhenius equation takes on a functional form that is more general than previously stated without recourse to tagging on ad hoc functional forms. Finally, we derive analytical models of chemical systems, in equilibrium, with carbon, hydrogen and oxygen. We include acetylene and are able to reproduce several key trends, versus temperature and carbon-to-oxygen ratio, published in the literature. The rich variety of behavior that mixing ratios exhibit as a function of the carbon-to-oxygen ratio is merely the outcome of stoichiometric book-keeping and not the direct consequence of temperature or pressure variations.Comment: Accepted by ApJ. 9 pages, 4 figure

Noise suppression in inverse weak value based phase detection

We examine the effect of different sources of technical noise on inverse weak value-based precision phase measurements. We find that this type of measurement is similarly robust to technical noise as related experiments in the weak value regime. In particular, the measurements considered here are robust to additive Gaussian white noise and angular jitter noise commonly encountered in optical experiments. Additionally, we show the same techniques used for precision phase measurement can be used with the same technical advantages for optical frequency measurements.Comment: 6 pages, 4 figure

Jefferson Makes a Major Contribution to Collaborating Across Borders, IV Conference

The fourth international Collaboration Across Borders conference (CAB IV) was held in Vancouver BC, Canada on June 12‐14, 2013. This conference, held every two years, attracts people involved in interprofessional education and care (IPEC) from across North America, and from other countries such as Japan, Australia and the European Union. The conference is a collaborative venture between the American Interprofessional Health Collaborative (AIHC) and the Canadian Interprofessional Health Collaborative (CIHC). The site of the conference alternates between the United States and Canada. As interest and involvement in interprofessional approaches to education and health care grows, so too does attendance at this meeting. The �irst conference, held at the University of Minnesota in 2007, attracted a little over 300 people. Subsequent meetings in Nova Scotia and Arizona saw attendance increase dramatically, reaching close to 750 in Arizona. This was the largest attendance ever at a conference devoted to interprofessional education. Attendance at the Vancouver conference exceeded that number

JCIPE to Host Fourth Biennial Conference on Interprofessional Education and Care

The Jefferson Center for Interprofessional Education (JCIPE) will host its’ fourth biennial conference on interprofessional education and care from Friday, October 10th through Sunday, October 12th. Entitled “Interprofessional Care for the 21st Century: Redefining Education and Practice,” the conference will bring individuals involved in interprofessional education and care together to share ideas, innovative programs and the latest research to help advance interprofessional approaches to education and care (IPE/C) across the country

Considering Cable Stretch in Logging Applications

This paper considers three methods for calculating the un-stretched length of a cable with significant self weight when the final static equilibrium conditions are known. The first method uses an average line tension and Hooke’s Law to estimate the un-stretched length. The second method uses a Lagrangian co-ordinate and Hooke’s Law to form an exact equation for the un-stretched length, given the assumption that the cable is linear elastic and the change in length is due to elastic stretch. The third method uses a Lagrangian coordinate; however, construction stretch is included in addition to elastic stretch. The results of this paper indicate the average tension is a suitable surrogate for a tension function that is a function of position when considering elongation to be the result of elastic stretch. When construction stretch is considered, the average tension method also performed well for cables with tensions less than one-third the minimum breaking strength