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Modeling and Interpreting the Effects of Spatial Resolution on Solar Magnetic Field Maps
Leka, K. D.; Barnes, G.
Different methods for simulating the effects of spatial resolution on magnetic field maps are compared, including those commonly used for inter-instrument comparisons. The investigation first uses synthetic data, and the results are confirmed with Hinode/SpectroPolarimeter data. Four methods are examined, one which manipulates the Stokes spectra t…
The Ultraviolet Spectral Energy Distributions of Quiescent Black Holes and Neutron Stars
Robinson, E. L.; Hynes, R. I.
We present Hubble Space Telescope/Advanced Camera for Surveys ultraviolet photometry of three quiescent black hole X-ray transients, X-ray Nova Muscae 1991 (GU Mus), GRO J0422+32 (V518 Per), and X-ray Nova Vel 1993 (MM Vel), and one neutron star system, Aql X-1. These are the first quiescent UV detections of these objects. All are detected at a mu…
First ever VLF monitoring of the lunar occultation of a solar flare during the 2010 annular solar eclipse and its effects on the D-region electron density profile
Chakrabarti, Sandip K.; Pal, Sujay; Maji, Surya K.
A ground based Very Low Frequency (VLF) radio receiver of Indian Centre for Space Physics located at Khukurdaha (22°27‧N, 87°45‧E) monitored the VLF signal at 19.8 kHz from the NWC station during a partial solar eclipse (maximum obscuration 75%) which took place on January 15, 2010. The receiver and the transmitter were on two opposite sides of th…
In-plane electric fields in magnetic islands during collisionless magnetic reconnection
Chen, Li-Jen; Roytershteyn, Vadim; Daughton, William +3 more
Magnetic islands are a common feature in both the onset and nonlinear evolution of magnetic reconnection. In collisionless regimes, the onset typically occurs within ion-scale current layers leading to the formation of magnetic islands when multiple X lines are involved. The nonlinear evolution of reconnection often gives rise to extended electron…
Identifying the Radio Bubble Nature of the Microwave Haze
Dobler, Gregory
Using seven-year data from the Wilkinson Microwave Anisotropy Probe, I identify a sharp "edge" in the microwave haze at high southern Galactic latitude (-55° < b < -35°) that is spatially coincident with the southern edge of the "Fermi haze/bubbles." This finding proves conclusively that the edge in the gamma rays is real (and not a processi…
Dynamo regime transition among Sun-like stars in M 34. A time evolution model of X-ray activity on the main sequence
Gondoin, P.
Context. The X-ray emission from late-type stars in open clusters exhibits two kinds of dependences on stellar rotation. While fast rotators have a relatively constant X-ray emission level, slower rotators show a decline of their X-ray emission with decreasing rotation rate. The physical significance of the transition between these two X-ray emiss…
Nonlinear Force-free Modeling of a Three-dimensional Sigmoid Observed on the Sun
Choe, G. S.; Inoue, S.; Magara, T. +1 more
In this work, we analyze the characteristics of the three-dimensional magnetic structure of a sigmoid observed over an active region (AR 10930) and followed by X-class flares. This is accomplished by combining a nonlinear force-free field (NLFFF) model of a coronal magnetic field and the high-resolution vector-field measurement of a photospheric m…
Analysis of GRB 080319B and GRB 050904 within the Fireshell Model: Evidence for a Broader Spectral Energy Distribution
Izzo, L.; Bernardini, M. G.; Patricelli, B. +5 more
The observation of GRB 080319B, with an isotropic energy E iso = 1.32 × 1054 erg, and GRB 050904, with E iso = 1.04 × 1054 erg, offers the possibility of studying the spectral properties of the prompt radiation of two of the most energetic gamma-ray bursts (GRBs). This allows us to probe the validity of …
Acoustic spectrum fitting for a large set of solar-like pulsators
Baudin, F.; Chaplin, W. J.; Elsworth, Y. +2 more
Asteroseismology provides the means both to constrain the global properties and to probe the internal structures of stars. Asteroseismic data are now available on large numbers of solar-type stars, thanks in particular to the CoRoT and Kepler space missions, and automated data-analysis pipelines are needed to provide efficient and timely results. …
Dielectric constant estimation of the uppermost Basal Unit layer in the martian Boreales Scopuli region
Orosei, Roberto; Pettinelli, Elena; Mattei, Elisabetta +3 more
An electromagnetic inversion model has been applied to echoes from the subsurface sounding Shallow Radar (SHARAD) to retrieve the dielectric properties of the uppermost Basal Unit (BU) beneath the North Polar Layered Deposits of Mars. SHARAD data have been carefully selected to satisfy the assumption of the inversion model which requires a stratig…