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The XMM-Newton serendipitous survey. IV. Optical identification of the XMM-Newton medium sensitivity survey (XMS)
Pérez-Fournon, I.; Motch, C.; Bromage, G. E. +54 more
Aims:X-ray sources at intermediate fluxes (a few × 10-14 erg cm-2 s-1) with a sky density of ~100 deg-2 are responsible for a significant fraction of the cosmic X-ray background at various energies below 10 keV. The aim of this paper is to provide an unbiased and quantitative description of the X-ray sou…
An XMM-Newton Observation of the Local Bubble Using a Shadowing Filament in the Southern Galactic Hemisphere
Kuntz, K. D.; Henley, David B.; Shelton, Robin L.
We present an analysis of the X-ray spectrum of the Local Bubble, obtained by simultaneously analyzing spectra from two XMM-Newton pointings on and off an absorbing filament in the southern Galactic hemisphere (b~-45deg). We use the difference in the Galactic column density in these two directions to deduce the contributions of the unab…
Sulfur volcanism on Io
Spencer, John; Yelle, Roger; Jessup, Kandis Lea
In February 2003, March 2003 and January 2004 Pele plume transmission spectra were obtained during Jupiter transit with Hubble's Space Telescope Imaging Spectrograph (STIS), using the 0.1″ wide slit and the G230LB grating. The STIS spectra covered the 2100-3100 Å wavelength regions and extended spatially along Io's limb encompassing the region dir…
Flow Field Evolution of a Decaying Sunspot
Liu, Chang; Denker, Carsten; Wang, Haimin +3 more
We study the evolution of the flows and horizontal proper motions in and around a decaying follower sunspot based on time sequences of two-dimensional spectroscopic observations in the visible and white-light imaging data obtained over 6 days from 2005 June 7 to 12. During this time period the sunspot decayed gradually to a pore. The spectroscopic…
Monte Carlo Simulation of Directivity of Interplanetary Radio Bursts
MacDowall, R. J.; Kaiser, M. L.; Thejappa, G.
We have developed a Monte Carlo simulation code to study the effects of refraction due to spatial variation of the solar wind density and scattering due to random density fluctuations on directivities, time profiles, and sizes and positions of the apparent sources of the interplanetary type II and type III radio bursts excited at the fundamental (…
A Streamer Ejection with Reconnection Close to the Sun
Warren, H. P.; Sheeley, N. R., Jr.; Wang, Y. -M.
We previously described coronal events that expand gradually outward over an interval of 1-2 days and then suddenly tear apart in the coronagraph's 2-6 Rsolar field of view to form an outgoing flux rope and an inward system of collapsing loops. Now, we combine LASCO white-light images of the outer corona with spectrally resolved EIT ima…
Deviations from He I Case B Recombination Theory and Extinction Corrections in the Orion Nebula
Martin, P. G.; Blagrave, K. P. M.; Dufour, R. J. +4 more
We are engaged in a comprehensive program to find reliable elemental abundances in and probe the physical structure of the Orion Nebula, the brightest and best-resolved H II region. In the course of developing a robust extinction correction covering our optical and UV FOS and STIS observations, we examined the decrement within various series of He…
Cosmic-Ray Modulation: An Empirical Relation with Solar and Heliospheric Parameters
Mavromichalaki, H.; Karalidi, T.; Paouris, E.
Long-term variations of galactic cosmic rays were compared with the behavior of various solar activity indices and heliospheric parameters during the current solar cycle. This study continues previous works where the cosmic-ray intensity for the solar cycles 20, 21, and 22 was well simulated from the linear combination of the sunspot number, the n…
The Width of a Solar Coronal Mass Ejection and the Source of the Driving Magnetic Explosion: A Test of the Standard Scenario for CME Production
Moore, Ronald L.; Sterling, Alphonse C.; Suess, Steven T.
We show that the strength (BFlare) of the magnetic field in the area covered by the flare arcade following a CME-producing ejective solar eruption can be estimated from the final angular width (Final θCME) of the CME in the outer corona and the final angular width (θFlare) of the flare arcade: BFlare~1.4…
The initial conditions of isolated star formation - VII. Spitzer mapping of pre-stellar cores
Ward-Thompson, D.; André, P.; Kirk, J. M.
We have retrieved Spitzer archive data of pre-stellar cores taken with the Multiband Imaging Photometer for Spitzer (MIPS) at a wavelength of 160 µm. Seventeen images, containing 18 cores, were constructed. Flux densities were measured for each core, and background estimates were made. Mean off-source backgrounds were found to be 48 +/- 10 M…