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11. Dynamical Magnetic Fields of Antialigned Nonspinning Dipoles

Abstract:: This movie shows the dynamical behavior of field lines seeded on one of the stars. We find a clear cyclical process operating in the magnetosphere. First, field lines from one star can attach to the second star. Second, as the orbit progresses these field lines develop twist and are expelled outward past the second star as closed loops. Third, these loops open up to infinity and then reconnect on the far side of the first star opposite to the second. Fourth, the orbital motion will bring the second star back into contact with the closed loops, and they reattach to the second star.
Type:: moving image
Issue Date:: 21 November 2013

12. An extended MHD study of the 16 October 2015 MMS diffusion region crossing

Abstract:: The Magnetospheric Multiscale (MMS) mission has given us unprecedented access to high cadence particle and field data of magnetic reconnection at Earth's magnetopause. MMS first passed very near an X-line on 16 October 2015, the Burch event, and has since observed multiple X-line crossings. Subsequent 3D particle-in-cell (PIC) modeling efforts of and comparison with the Burch event have revealed a host of novel physical insights concerning magnetic reconnection, turbulence induced particle mixing, and secondary instabilities. In this study, we employ the Gkeyll simulation framework to study the Burch event with different classes of extended, multi-fluid magnetohydrodynamics (MHD), including models that incorporate important kinetic effects, such as the electron pressure tensor, with physics-based closure relations designed to capture linear Landau damping. Such fluid modeling approaches are able to capture different levels of kinetic physics in global simulations and are generally less costly than fully kinetic PIC. We focus on the additional physics one can capture with increasing levels of fluid closure refinement via comparison with MMS data and existing PIC simulations. In particular, we find that the ten-moment model well captures the agyrotropic structure of the pressure tensor in the vicinity of the X-line and the magnitude of anisotropic electron heating observed in MMS and PIC simulations. However, the ten-moment model has difficulty resolving the lower hybrid drift instability, which has been observed to plays a fundamental role in heating and mixing electrons in the current layer.
Type:: Dataset

13. Dust and Starlight Maps for Galaxies in the KINGFISH Sample

Author(s):: Aniano, G.; Draine, B.T.; Hunt, L.K.; Sandstrom, K.; Calzetti, D.; Kennicutt, R.C.; Dale, D.A.; Galametz, M.; Gordon, K.D.; Leroy, A.K.; Smith, J.-D.T.; Roussel, H.; Sauvage, M.; Walter, F.; Armus, L.; Bolatto, A.D.; Boquien, M.; Crocker, A.; De Looze, I.; Donovan Meyer, J.; Helou, G.; Hinz, J.; Johnson, B.D.; Koda, J.; Miller, A.; Montiel, E.; Murphy, E.J.; Relano, M.; Rix, H.-W.; Schinnerer, E.; Skibba, R.; Wolfire, M.G.; Engelbracht, C.W.
Abstract:: Dust and starlight have been modeled for the KINGFISH project galaxies. For each pixel in each galaxy, we estimate: (1) dust surface density; (2) q_PAH, the dust mass fraction in PAHs; (3) distribution of starlight intensities heating the dust; (4) luminosity emitted by the dust; and (5) dust luminosity from regions with high starlight intensity. The modeling is as described in the paper "Modeling Dust and Starlight in Galaxies Observed by Spitzer and Herschel: The KINGFISH Sample", by G. Aniano, B.T. Draine, L.K. Hunt, K. Sandstrom, D. Calzetti, R.C. Kennicutt, D.A, Dale, and 26 other authors, accepted for publication in The Astrophysical Journal.
Type:: Dataset and Image

14. Fermi-LAT Example Data and Template

Abstract:: A subset of the Fermi-LAT public data for use with NPTFit: https://github.com/bsafdi/NPTFit The data here is for use with the Jupyter example notebooks provided with the main code. Details of the files provided are given below. All files are provided as numpy arrays binned as nside=128 HEALPix maps. For the full public data, see: http://fermi.gsfc.nasa.gov/ssc/data/access/
Type:: Dataset

15. Graphite: Dielectric Tensor and Cross Sections for Spheres and Spheroids

Abstract:: Dielectric tensor for crystalline graphite from X-ray to microwave frequencies, as discussed in the paper "Graphite Revisited" (Draine 2016, Astrophysical Journal, in press). Cross sections for absorption and scattering by graphite spheres and spheroids are also tabulated, as well as Planck-averaged cross sections for absorption and scattering of radiation with a Planck spectrum.
Type:: Dataset

16. Light Curves from a Search for Variable Stars in the Globular Cluster M4 with K2

Abstract:: The data are 4554 light curves derived from images taken of the globular cluster M4 by the Kepler space telescope during the K2 portion of its mission, specifically during Campaign 2 of that mission, which occurred in 2014. A total of 3856 images were taken over approximately three months at a cadence of approximately half an hour. The purpose of these observations was to find stars and other objects that vary in brightness over time --- variable stars. Also included is a table with associated information for each of the 4554 objects and their light curves.
Type:: collection and Dataset