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Eruption of a Multiple-Turn Helical Magnetic Flux Tube in a Large Flare: Evidence for External and Internal Reconnection That Fits the Breakout Model of Solar Magnetic Eruptions
DOI: 10.1086/422132 Bibcode: 2004ApJ...611..545G

Moore, R. L.; Gary, G. Allen

We present observations and an interpretation of a unique multiple-turn spiral flux tube eruption from active region 10030 on 2002 July 15. The TRACE C IV observations clearly show a flux tube that is helical and erupting from within a sheared magnetic field. These observations are interpreted in the context of the breakout model for magnetic fiel…

2004 The Astrophysical Journal
SOHO 134
Hubble Space Telescope STIS Ultraviolet Spectral Evidence of Outflow in Extreme Narrow-Line Seyfert 1 Galaxies. I. Data and Analysis
DOI: 10.1086/422088 Bibcode: 2004ApJ...611..107L

Leighly, Karen M.; Moore, John R.

We present Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph observations of two extreme narrow-line Seyfert 1 galaxies (NLS1's), IRAS 13224-3809 and 1H 0707-495. The spectra are characterized by very blue continua; broad, strongly blueshifted high-ionization lines (including C IV and N V); and narrow, symmetric intermediate- (incl…

2004 The Astrophysical Journal
eHST 134
The distance to the giant elliptical galaxy NGC 5128
DOI: 10.1051/0004-6361:20034031 Bibcode: 2004A&A...413..903R

Rejkuba, M.

The distance to NGC 5128, the central galaxy of the Centaurus group and the nearest giant elliptical to us, has been determined using two independent distance indicators: the Mira period-luminosity (PL) relation and the luminosity of the tip of the red giant branch (RGB). The data were taken at two different locations in the halo of NGC 5128 with …

2004 Astronomy and Astrophysics
Hipparcos 134
Time-Distance Helioseismology: Noise Estimation
DOI: 10.1086/423367 Bibcode: 2004ApJ...614..472G

Birch, A. C.; Gizon, L.

As in global helioseismology, the dominant source of noise in time-distance helioseismology measurements is realization noise due to the stochastic nature of the excitation mechanism of solar oscillations. Characterizing noise is important for the interpretation and inversion of time-distance measurements. In this paper we introduce a robust defin…

2004 The Astrophysical Journal
SOHO 134
XMM-Newton observations of the supernova remnant RX J1713.7-3946 and its central source
DOI: 10.1051/0004-6361:20041154 Bibcode: 2004A&A...427..199C

Ballet, J.; Decourchelle, A.; Giacani, E. +3 more

We present new results from the observations of the supernova remnant (SNR) RX J1713.7-3946 (also G347.3-0.5) performed in five distinct pointings with the EPIC instrument on board the satellite XMM-Newton. RX J1713.7-3946 is a shell-type SNR dominated by synchrotron radiation in the X-rays. Its emission (emis…

2004 Astronomy and Astrophysics
XMM-Newton 133
A Numerical Model of a Coronal Mass Ejection: Shock Development with Implications for the Acceleration of GeV Protons
DOI: 10.1086/392504 Bibcode: 2004ApJ...605L..73R

Gombosi, T. I.; Roussev, I. I.; Lee, M. A. +3 more

The initiation and evolution of the coronal mass ejection, which occurred on 1998 May 2 in NOAA Active Region 8210, are modeled using a fully three-dimensional, global MHD code. The initial magnetic field for the model is based on magnetogram data from the Wilcox Solar Observatory, and the solar eruption is initiated by slowly evolving the boundar…

2004 The Astrophysical Journal
SOHO 133
GEMS Imaging of Red-Sequence Galaxies at z~0.7: Dusty or Old?
DOI: 10.1086/381388 Bibcode: 2004ApJ...600L..11B

Bell, Eric F.; Somerville, Rachel S.; Wisotzki, Lutz +13 more

We have used the 30'×30' Hubble Space Telescope image mosaic from the Galaxy Evolution from Morphology and Spectral energy distributions (GEMS) project in conjunction with the COMBO-17 deep photometric redshift survey to define a sample of nearly 1500 galaxies with 0.65<=z<=0.75. With this sample, we can study the distr…

2004 The Astrophysical Journal
eHST 133
Dynamics of solar coronal loops. II. Catastrophic cooling and high-speed downflows
DOI: 10.1051/0004-6361:20040403 Bibcode: 2004A&A...424..289M

Peter, H.; Hansteen, V. H.; Müller, D. A. N.

This work addresses the problem of plasma condensation and ``catastrophic cooling'' in solar coronal loops. We have carried out numerical calculations of coronal loops and find several classes of time-dependent solutions (static, periodic, irregular), depending on the spatial distribution of a temporally constant energy deposition in the loop. Dyn…

2004 Astronomy and Astrophysics
SOHO 131
Long-Term Cosmic-Ray Modulation in the Heliosphere
DOI: 10.1086/381649 Bibcode: 2004ApJ...603..744F

Ferreira, S. E. S.; Potgieter, M. S.

A time-dependent model based on a numerical solution of Parker's transport equation is used to model the modulation of cosmic-ray protons, electrons, and helium for full 11 year and 22 year modulation cycles using a compound approach. This approach incorporates the concept of propagating diffusion barriers, increases in the heliospheric magnetic f…

2004 The Astrophysical Journal
Ulysses 131
The nature of the Galactic Center source IRS 13 revealed by high spatial resolution in the infrared
DOI: 10.1051/0004-6361:20034147 Bibcode: 2004A&A...423..155M

Rigaut, F.; Paumard, T.; Stolovy, S. R. +1 more

High spatial resolution observations in the 1 to 3.5 µm/ region of the Galactic Center source known historically as IRS 13 are presented. They include ground-based adaptive optics images in the H, Kp (2.12/0.4 µm) and L bands, HST-NICMOS data in filters between 1.1 and 2.2 µm, and integral field spectroscopic d…

2004 Astronomy and Astrophysics
eHST 131