This paper describes the Pegasus framework that can be used to map complex scientific workflows onto distributed resources. Pegasus enables users to represent the workflows at an abstract level without needing to worry about the particulars of the target execution systems. The paper describes general issues in mapping applications and the functionality of Pegasus. We present the results of improving application performance through workflow restructuring which clusters multiple tasks in a workflow into single entities. A real-life astronomy application is used as the basis for the study.

We describe the contents and functionality of the NASA Exoplanet Archive, a database and tool set funded by NASA to support astronomers in the exoplanet community. The current content of the database includes interactive tables containing properties of all published exoplanets, Kepler planet candidates, threshold-crossing events, data validation reports and target stellar parameters, light curves from the Kepler and CoRoT missions and from several ground-based surveys, and spectra and radial velocity measurements from the literature. Tools provided to work with these data include a transit ephemeris predictor, both for single planets and for observing locations, light curve viewing and normalization utilities, and a periodogram and phased light curve service. The archive can be accessed at http://exoplanetarchive.ipac.caltech.edu.Comment: Accepted for publication in the Publications of the Astronomical Society of the Pacific, 4 figure

Abstract

A new, 2.8 deg^2 J,H,K_s infrared survey from the 2MASS 6x program across the extent of the optical disk of the Andromeda (M31) galaxy provides a clear view of the M31 center almost completely unfettered by dust extinction, and reveals a high contrast bulge with extremely boxy isophotes dominating the NIR light to a semi-major axis of ~700''(2.6 kpc). The inner bulge (<~50'') is relatively circular, but shows some isophotal twisting. Beyond this, the ellipticity and boxiness of the bulge increase with radius -- achieving a boxiness that rivals that of any other known disk galaxy observed in the near infrared -- and the position angle is constant at ~50 deg, which is about 10 deg higher than the position angle of the M31 disk. Boxy bulges in highly inclined disks have been shown to be the vertical structure of bars, and self-consistent, N-body modeling specific to the NIR images presented here can reproduce the observed NIR M31 features with a combination of a classical bulge and a boxy bulge/bar. Beyond the boxy bulge region and nearly along the 40 deg position angle of the disk a narrow ridge of infrared flux, which can be identified with the thin part of the bar, more or less symmetrically extends into the inner disk at semi-major axis radii of 700'' to 1200'' or more. Little variation in the morphology or relative brightnesses of these various M31 structures is seen across the NIR bands (i.e., no color gradients are seen). These new data verify that M31 is a barred spiral galaxy like the Milky Way.Comment: Suibmitted to Astrophysical Journal Letter