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A Multi-Wavelength Spectral and Polarimetric Study of the Jet of 3C 264
Kastner, J. H.; Sparks, W. B.; Birkinshaw, M. +12 more
We present a comprehensive multi-band spectral and polarimetric study of the jet of 3C 264 (NGC 3862). Included in this study are three Hubble Space Telescope (HST) optical and ultraviolet polarimetry data sets, along with new and archival Very Large Array radio imaging and polarimetry, a re-analysis of numerous HST broadband data sets from the ne…
Revealing the Fine Structure of Coronal Dimmings and Associated Flows with Hinode/EIS. Implications for Understanding the Source Regions of Sustained Outflow Following CMEs
van Driel-Gesztelyi, L.; Harra, L. K.; Wills-Davey, M. J. +1 more
We study two CME events on 13 and 14 December 2006 that were associated with large-scale dimmings. We study the eruptions from pre-event on 11 December through the recovery on 15 December, using a combination of Hinode/EIS, SOHO/EIT, SOHO/MDI, and MLSO Hα data. The GOES X-class flares obscured the core dimmings, but secondary dimmings developed re…
The star cluster-field star connection in nearby spiral galaxies. I. Data analysis techniques and application to NGC 4395
Larsen, S. S.; Silva-Villa, E.
Context. It is generally assumed that a large fraction of stars are initially born in clusters. However, a large fraction of these disrupt on short timescales and the stars end up belonging to the field. Understanding this process is of paramount importance if we wish to constrain the star formation histories of external galaxies using star cluste…
Observation of the multifractal spectrum in solar wind turbulence by Ulysses at high latitudes
Wawrzaszek, Anna; Macek, Wieslaw M.
The aim of our study is to examine the question of multifractal scaling properties of turbulence in the solar wind at high latitudes. We analyze time series of the velocities of the solar wind during solar minimum (1994-1997, 2006-2007) at various heliographic latitudes measured in situ by Ulysses, which is the only mission that has investigated p…
Helioseismic Detection of Deep Meridional Flow
Gough, Douglas; Hindman, Bradley W.
Steady meridional flow does not make any first-order perturbations to the frequencies of helioseismic normal modes. It does, however, Doppler shift the local wavenumber, thereby distorting the eigenfunctions. For high-degree modes, whose peaks in a power spectrum are blended into continuous ridges, the effect of the distortion is to shift the loca…
Quantifying the Evolving Magnetic Structure of Active Regions
Gallagher, Peter T.; McAteer, R. T. James; Conlon, Paul A. +1 more
The topical and controversial issue of parameterizing the magnetic structure of solar active regions has vital implications in the understanding of how these structures form, evolve, produce solar flares, and decay. This interdisciplinary and ill-constrained problem of quantifying complexity is addressed by using a two-dimensional wavelet transfor…
The Electrical Current Density Vector in the Inner Penumbra of a Sunspot
Martínez Pillet, V.; Ruiz Cobo, B.; Puschmann, K. G.
We determine the entire electrical current density vector in a geometrical three-dimensional volume of the inner penumbra of a sunspot from an inversion of spectropolarimetric data obtained with Hinode/SP. Significant currents are seen to wrap around the hotter, more elevated regions with lower and more horizontal magnetic fields that harbor stron…
The Difference in Narrow Fe Kα Line Emission Between Seyfert 1 and Seyfert 2 Galaxies
Wang, Jun-Xian; Liu, Teng
We compile a sample of 89 Seyfert galaxies with both [O IV] 25.89 µm line luminosities observed by Spitzer IRS and X-ray spectra observed by XMM-Newton EPIC. Using [O IV] emission as a proxy for active galactic nucleus (AGN) intrinsic luminosity, we find that although type 2 AGNs have higher line equivalent widths, the narrow Fe Kα lines in …
On Spectropolarimetric Measurements with Visible Lines
Bellot Rubio, L. R.; del Toro Iniesta, J. C.; Orozco Suárez, D.
The ability of new instruments for providing accurate inferences of vector magnetic fields and line-of-sight velocities of the solar plasma depends a great deal on the sensitivity to these physical quantities of the spectral lines chosen to be measured. Recently, doubts have been raised about visible Stokes profiles to provide a clear distinction …
Near-infrared/optical identification of five low-luminosity X-ray pulsators
Paul, Biswajit; Wijnands, Rudy; Degenaar, Nathalie +2 more
We present the identification of the most likely near-infrared (NIR)/optical counterparts of five low-luminosity X-ray pulsators (AX J1700.1-4157, AX J1740.1-2847, AX J1749.2-2725, AX J1820.5-1434 and AX J1832.3-0840) which have long pulse periods (>150 s). The X-ray properties of these systems suggest that they are likely members of persistent…