High-precision photometry of WASP-12 b transits

The transiting extrasolar planet WASP-12 b was found to be one of the most intensely irradiated exoplanets. It is unexpectedly bloated and is losing mass that may accrete into the host star. Our aim was to refine the parameters of this intriguing system and search for signs of transit timing variations. We gathered high-precision light curves for two transits of WASP-12 b. Assuming various limb-darkening laws, we generated best-fitting models and redetermined parameters of the system. Error estimates were derived by the prayer bead method and Monte Carlo simulations. System parameters obtained by us are found to agree with previous studies within one sigma. Use of the non-linear limb-darkening laws results in the best-fitting models. With two new mid-transit times, the ephemeris was refined to BJD(TDB)=(2454508.97682 +/- 0.00020) + (1.09142245 +/- 0.00000033) E. Interestingly, indications of transit timing variation are detected at the level of 3.4 sigma. This signal can be induced by an additional planet in the system. Simplified numerical simulations shows that a perturber could be a terrestrial-type planet if both planets are in a low-order orbital resonance. However, we emphasise that further observations are needed to confirm variation and to constrain properties of the perturber.Comment: 5 pages, 3 figures, accepted for publication in A&

AGRICULTURAL POLICIES AND ECONOMIC GROWTH

Agricultural and Food Policy,

High-precision photometry by telescope defocussing. III. The transiting planetary system WASP-2

We present high-precision photometry of three transits of the extrasolar planetary system WASP-2, obtained by defocussing the telescope, and achieving point-to-point scatters of between 0.42 and 0.73 mmag. These data are modelled using the JKTEBOP code, and taking into account the light from the recently-discovered faint star close to the system. The physical properties of the WASP-2 system are derived using tabulated predictions from five different sets of stellar evolutionary models, allowing both statistical and systematic errorbars to be specified. We find the mass and radius of the planet to be M_b = 0.847 +/- 0.038 +/- 0.024 Mjup and R_b = 1.044 +/- 0.029 +/- 0.015 Rjup. It has a low equilibrium temperature of 1280 +/- 21 K, in agreement with a recent finding that it does not have an atmospheric temperature inversion. The first of our transit datasets has a scatter of only 0.42 mmag with respect to the best-fitting light curve model, which to our knowledge is a record for ground-based observations of a transiting extrasolar planet.Comment: Accepted for publication in MNRAS. 9 pages, 3 figures, 10 table

The ultra-compact binary candidate KUV 23182+1007 is a bright quasar

KUV 23182+1007 was identified as a blue object in the Kiso UV Survey in the 1980s. Classification-dispersion spectroscopy showed a featureless continuum except for a strong emission line in the region of He II 4686 A. This is a hallmark of the rare AM CVn class of cataclysmic variable star, so we have obtained a high-S/N blue spectrum of this object to check its classification. Instead, the spectrum shows a strong quasar-like emission line centred on 4662 A. Comparison with the SDSS quasar template spectra confirms that KUV 23182+1007 is a quasar with a redshift of z = 0.665.Comment: 4 pages, 2 figures, to appear in IBVS. Data are available from http://www.astro.keele.ac.uk/~jkt

Bayesian mass and age estimates for transiting exoplanet host stars

The mean density of a star transited by a planet, brown dwarf or low mass star can be accurately measured from its light curve. This measurement can be combined with other observations to estimate its mass and age by comparison with stellar models. Our aim is to calculate the posterior probability distributions for the mass and age of a star given its density, effective temperature, metallicity and luminosity. We computed a large grid of stellar models that densely sample the appropriate mass and metallicity range. The posterior probability distributions are calculated using a Markov-chain Monte-Carlo method. The method has been validated by comparison to the results of other stellar models and by applying the method to stars in eclipsing binary systems with accurately measured masses and radii. We have explored the sensitivity of our results to the assumed values of the mixing-length parameter, $\alpha_{\rm MLT}$, and initial helium mass fraction, Y. For a star with a mass of 0.9 solar masses and an age of 4 Gyr our method recovers the mass of the star with a precision of 2% and the age to within 25% based on the density, effective temperature and metallicity predicted by a range of different stellar models. The masses of stars in eclipsing binaries are recovered to within the calculated uncertainties (typically 5%) in about 90% of cases. There is a tendency for the masses to be underestimated by about 0.1 solar masses for some stars with rotation periods P$_{\rm rot}< 7$d. Our method makes it straightforward to determine accurately the joint posterior probability distribution for the mass and age of a star eclipsed by a planet or other dark body based on its observed properties and a state-of-the art set of stellar models.Comment: Accepted for publication in A&A. 9 pages, 4 figures. Source code for the software described is available from http://sourceforge.net/projects/bagemas

Forgotten Feminine Foundations: Content Analysis of Secondary World History Textbooks\u27 Inclusion of Female Agency in the Rise of Judaism, Christianity, and Islam

This study investigated women’s agency in the emergence accounts of Judaism, Christianity, and Islam in nine twenty-first century United States’ world history textbooks through a feminist lens. The collected data were analyzed via critical discourse analysis and content analysis to determine if traditional patterns of female marginalization in content and imagery existed. The quantitative and qualitative findings in both text and imagery indicated that all textbooks in this sample supported a traditional content structure on both an individual and collective whole basis. This study then concluded that these gender-imbalanced accounts of world religions may serve as an avenue in which distorted and/or incorrect information may be communicated to students regarding the interconnectedness of culture and religion, potentially misshaping students’ knowledge cultivation processes. Additionally, traditional content formatting may also reinforce existing negative stereotypes concerning women in religion and women overall. To rectify these transgressions, this study offers educators and textbook publishers succinct, provocative information on seven prominent religious women within Judaism, Christianity, and Islam whose contributions assisted in the rise of their religions

KIC 4247791: A SB4 system with two eclipsing binaries (2EBs)

KIC 4247791 is an eclipsing binary observed by the Kepler satellite mission. We wish to determine the nature of its components and in particular the origin of a shallow dip in its Kepler light curve that previous investigations have been unable to explain in a unique way. We analyze newly obtained high-resolution spectra of the star using synthetic spectra based on atmosphere models, derive the radial velocities of the stellar components from cross-correlation with a synthetic template, and calculate the orbital solution. We use the JKTEBOP program to model the Kepler light curve of KIC 4247791. We find KIC 4247791 to be a SB4 star. The radial velocity variations of its four components can be explained by two separate eclipsing binaries. In contradiction to previous photometric findings, we show that the observed composite spectrum as well as the derived masses of all four of its components correspond to spectral type F. The observed small dip in the light curve is not caused by a transit-like phenomenon but by the eclipses of the second binary system. We find evidence that KIC 4247791 might belong to the very rare hierarchical SB4 systems with two eclipsing binaries.Comment: 6 pages, 8 figures, 2 table

Shedding Gender Stigmas: Work-life Balance Equity in the 21st Century

The gender stigma of work-life balance (WLB) policies as concessions for mothers and female caregivers originated with the push by the Women’s Movement for gender workplace equity in the late 20th century. Unfortunately, this perception continues in the 21st century and retains the additional stigma of employee participation in these policies–—regardless of gender–—as a detrimental career move. Thus, home and work responsibilities for professionals of all genders who desire more occupational flexibility remain unreconciled. Despite this dominant national and international outlook, this article encourages new century organizations and profes- sionals to reject the traditional perception of occupational inequity through gender- colored glasses and instead contemplate the benefits of WLB policies void of gender stigmas. Specifically, organizations could re-create workplace culture with stigma- free WLB policies through administrative leaders’ embracement of and participation in such policies, which may pave the way for establishing occupational equity. Through workplace culture re-creation, organizations may then offer employees–—regardless of gender, marital status, or company position–—flexible work options to assist them in leading happy, healthy, and more productive lives.https://digitalcommons.snc.edu/faculty_staff_works/1001/thumbnail.jp

Map It! Creating Meaningful Learning Experiences in Social Studies with IHMC CmapTools

As a free software tool, IHMC CmapTools redefines the concept mapping learning strategy with an infusion of technology to provide students with meaningful and non-rote learning experiences. The following review discusses what IHMC CmapTools is, the literature-supported academic benefits of student-employed concept mapping, and how my secondary social studies colleague and I introduced this software to his students to create meaningful learning opportunities with social studies content. After working with IHMC CmapTools for over four years in both social studies and non-social studies classes, I would strongly encourage social studies educators in grades 5-12 to consider implementing this tool in their instruction as a means of enriching both their students’ engagement with social studies material and their students’ understanding of their own metacognitive processes.https://digitalcommons.snc.edu/faculty_staff_works/1002/thumbnail.jp

On the (Male) Fringes: How Early Religious Women remain “Subordinate” in World History Textbooks

Second Wave feminist researchers identified male-dominated curriculum formats in late twentieth century curriculum materials. This study builds off their work and advances the conversation of women’s inclusion by current United States secondary world history textbook content via a feminist lens to determine the extent of women’s agency in the accounts of Judaism, Christianity, and Islam. The purpose was to determine if textbooks portrayed these patriarchal religions as exclusively male, thereby presenting inaccurate portrayals of the religions and the agents involved, which directly violates NCSS Standards. This study used critical discourse analysis to identify patterns of female marginalization and omission, indicating that modern textbooks still use male-dominated content. This article concludes with pertinent information about early female religious leaders to promote more gender-balanced religious agency discussions in the classroom.https://digitalcommons.snc.edu/faculty_staff_works/1011/thumbnail.jp