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The Exoplanet Orbit Database (EOD) compiles orbital, transit, host star, and other parameters of robustly detected exoplanets reported in the peer-reviewed literature. The EOD can be navigated through the Exoplanet Data Explorer (EDE) Plotter and Tab le, available on the World Wide Web at exoplanets.org. The EOD contains data for 1492 confirmed exoplanets as of July 2014. The EOD descends from a table in Butler et al. (2002) and the Catalog of Nearby Exoplanets (Butler et al. 2006), and the first complete documentation for the EOD and the EDE was presented in Wright et al. (2011). In this work, we describe our work since then. We have expanded the scope of the EOD to include secondary eclipse parameters, asymmetric uncertainties, and expanded the EDE to include the sample of over 3000 Kepler Objects of Interest (KOIs), and other real planets without good orbital parameters (such as many of those detected by microlensing and imaging). Users can download the latest version of the entire EOD as a single comma separated value file from the front page of exoplanets.org.
We report the radial-velocity discovery of a second planetary mass companion to the K0 V star HD 37605, which was already known to host an eccentric, P~55 days Jovian planet, HD 37605b. This second planet, HD 37605c, has a period of ~7.5 years with a low eccentricity and an Msini of ~3.4 MJup. Our discovery was made with the nearly 8 years of radial velocity follow-up at the Hobby-Eberly Telescope and Keck Observatory, including observations made as part of the Transit Ephemeris Refinement and Monitoring Survey (TERMS) effort to provide precise ephemerides to long-period planets for transit follow-up. With a total of 137 radial velocity observations covering almost eight years, we provide a good orbital solution of the HD 37605 system, and a precise transit ephemeris for HD 37605b. Our dynamic analysis reveals very minimal planet-planet interaction and an insignificant transit time variation. Using the predicted ephemeris, we performed a transit search for HD 37605b with the photometric data taken by the T12 0.8-m Automatic Photoelectric Telescope (APT) and the Microvariability and Oscillations of Stars (MOST) satellite. Though the APT photometry did not capture the transit window, it characterized the stellar activity of HD 37605, which is consistent of it being an old, inactive star, with a tentative rotation period of 57.67 days. The MOST photometry enabled us to report a dispositive null detection of a non-grazing transit for this planet. Within the predicted transit window, we exclude an edge-on predicted depth of 1.9% at >>10sigma, and exclude any transit with an impact parameter b>0.951 at greater than 5sigma. We present the BOOTTRAN package for calculating Keplerian orbital parameter uncertainties via bootstrapping. We found consistency between our orbital parameters calculated by the RVLIN package and error bars by BOOTTRAN with those produced by a Bayesian analysis using MCMC.
Using the 4 Ms Chandra Deep Field-South (CDF-S) survey, we have identified a sample of 6845 X-ray undetected galaxies that dominates the unresolved ~ 20-25% of the 6-8 keV cosmic X-ray background (XRB). This sample was constructed by applying mass an d color cuts to sources from a parent catalog based on GOODS-South HST z-band imaging of the central 6-radius area of the 4 Ms CDF-S. The stacked 6-8 keV detection is significant at the 3.9 sigma level, but the stacked emission was not detected in the 4-6 keV band which indicates the existence of an underlying population of highly obscured active galactic nuclei (AGNs). Further examinations of these 6845 galaxies indicate that the galaxies on the top of the blue cloud and with redshifts of 1 < z < 3, magnitudes of 25 < z_850 < 28, and stellar masses of 2E8 < M_star/M_sun < 2E9 make the majority contributions to the unresolved 6-8 keV XRB. Such a population is seemingly surprising given that the majority of the X-ray detected AGNs reside in massive (> ~1E10 M_sun) galaxies. We discuss constraints upon this underlying AGN population, supporting evidence for relatively low-mass galaxies hosting highly obscured AGNs, and prospects for further boosting the stacked signal.
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