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On the Generation, Propagation, and Reflection of Alfvén Waves from the Solar Photosphere to the Distant Heliosphere

Cranmer, S. R.; van Ballegooijen, A. A.

We present a comprehensive model of the global properties of Alfvén waves in the solar atmosphere and the fast solar wind. Linear non-WKB wave transport equations are solved from the photosphere to a distance past the orbit of the Earth, and for wave periods ranging from 3 s to 3 days. We derive a radially varying power spectrum of kinetic and mag…

Origin of the Marsden and Kracht Groups of Sunskirting Comets. I. Association with Comet 96P/Machholz and Its Interplanetary Complex

Sekanina, Zdenek; Chodas, Paul W.

Of the three major groups of comets approaching the Sun to between 6 and 12 solar radii and discovered with the coronagraphs on board SOHO, we investigate the Marsden and Kracht groups. We call these comets ``sunskirters'' to distinguish them from the Kreutz system sungrazers. Our objective is to understand the origin, history, and orbital evoluti…

A Solar Minimum Irradiance Spectrum for Wavelengths below 1200 Å

Warren, Harry P.

NRLEUV represents an independent approach to modeling the Sun's EUV irradiance and its variability. Our model utilizes differential emission measure distributions derived from spatially and spectrally resolved solar observations, full-disk solar images, and a database of atomic physics parameters to calculate the solar EUV irradiance. In this pape…

Time-Distance Helioseismology: Inversion of Noisy Correlated Data

Kosovichev, A. G.; Birch, A. C.; Gizon, L. +2 more

In time-distance helioseismology most inversion procedures ignore the correlations in the data errors. Here we simulate the travel-time perturbations of wavepackets that result from known distributions of sound speed inhomogeneities. The forward and inverse problems are carried out using recently developed Born approximation sensitivity kernels. A…

Magnetic Fields from SOHO MDI Converted to the Mount Wilson 150 Foot Solar Tower Scale

Ulrich, Roger K.; Tran, Tham; Bertello, Luca +1 more

In order to permit the construction of long-duration time series dependent on the Sun's magnetic field, this paper presents a detailed cross-correlation between sets of simultaneous magnetograms from the Mount Wilson Observatory (MWO) and the Michelson Doppler Imager (MDI) aboard the SOHO spacecraft. The MWO 150 foot (45.72 m) solar tower telescop…