Science Archives Publication System

Persistent North-South Alignment of the Solar Supergranulation

DOI: 10.1086/420691 Bibcode: 2004ApJ...608.1167L

Toomre, Juri; Lisle, Jason P.; Rast, Mark P.

We have found evidence of an alignment of the solar supergranulation in the direction parallel to the Sun's rotation axis. Signatures of the alignment are apparent in both time-averaged images and in three-dimensional power spectra. The north-south organization is persistent in time, extending over many supergranular lifetimes. It occurs over a wi…

2004 • The Astrophysical Journal

SOHO 35

Solar cycle dependence of the helium focusing cone from SOHO/UVCS observations. Electron impact rates and associated pickup ions

DOI: 10.1051/0004-6361:200400028 Bibcode: 2004A&A...426..867L

Bertaux, J. -L.; Raymond, J. C.; Uzzo, M. +5 more

The Ultraviolet Coronograph on board SOHO (UVCS) has observed the 58.4 nm glow of the interplanetary He focusing cone at regular intervals since 1996. The intensity decrease with time already observed during the first two years (Michels et al. \cite{michels}) has dramatically amplified during the solar activity increase. Intensities seem to reach …

2004 • Astronomy and Astrophysics

SOHO 35

The Unusual Tidal Dwarf Candidate in the Merger System NGC 3227/3226: Star Formation in a Tidal Shock?

DOI: 10.1086/423732 Bibcode: 2004ApJ...614..648M

Forbes, Duncan A.; Schinnerer, Eva; Mundell, Carole G. +2 more

We report the discovery of active star formation in the H I cloud associated with the interacting Seyfert system NGC 3227/3226 that was originally identified as a candidate tidal dwarf galaxy (TDG) by Mundell et al. and that we name J1023+1952. We present broadband optical B, R, I (from the Isaac Newton Telescope), and ultraviolet images (from XMM…

2004 • The Astrophysical Journal

XMM-Newton 35

Bow shock specularly reflected ions in the presence of low-frequency electromagnetic waves: a case study

DOI: 10.5194/angeo-22-2325-2004 Bibcode: 2004AnGeo..22.2325M

Lundin, R.; Balogh, A.; Dandouras, I. +14 more

Available from http://www.copernicus.org/site/EGU/annales/22/7/2325.htm?FrameEngine=false;

2004 • Annales Geophysicae

Cluster 35

On the Wolf-Rayet counterpart to IC 10 X-1

DOI: 10.1051/0004-6361:20031762 Bibcode: 2004A&A...414L..45C

Crowther, P. A.; Clark, J. S.

Recent CHANDRA observations of the starburst galaxy IC 10 have resulted in an improved position for the bright (>10³⁸ erg s^-1) X-ray source IC 10 X-1. We discuss arguments in favour of the Wolf-Rayet star #17-A from Massey et al. and Crowther et al. being the optical counterpart; alter…

2004 • Astronomy and Astrophysics

eHST 35

Studies of Microflares in RHESSI Hard X-Ray, Big Bear Solar Observatory Hα, and Michelson Doppler Imager Magnetograms

DOI: 10.1086/381799 Bibcode: 2004ApJ...604..442L

Krucker, Säm; Liu, Chang; Qiu, Jiong +2 more

In this paper, we present a study of the morphology of 12 microflares jointly observed by RHESSI in the energy range from 3 to 15 keV and by Big Bear Solar Observatory (BBSO) at the Hα line. They are A2-B3 events in GOES classification. From their time profiles, we find that all of these microflares are seen in soft X-ray, hard X-ray, and Hα wavel…

2004 • The Astrophysical Journal

SOHO 35

Long-lived triaxiality in the dynamically old elliptical galaxy NGC 4365: a limit on chaos and black hole mass

DOI: 10.1111/j.1365-2966.2004.08062.x Bibcode: 2004MNRAS.353....1S

Bacon, Roland; Emsellem, Eric; Peletier, Reynier F. +1 more

Supermassive black holes in the centres of giant elliptical galaxies are thought to be capable of inducing chaos and eliminating or preventing triaxiality in their hosts if they are sufficiently massive. We address whether this process operates in real systems, by modelling the stellar kinematics of the old elliptical NGC 4365. This galaxy has a m…

2004 • Monthly Notices of the Royal Astronomical Society

eHST 35

Spectral evolution of weak bursts from SGR 1806-20 observed with INTEGRAL

DOI: 10.1051/0004-6361:20040080 Bibcode: 2004A&A...417L..45G

Hurley, K.; Götz, D.; Mereghetti, S. +1 more

We report on bursts from the Soft Gamma-Ray Repeater SGR 1806-20 detected with INTEGRAL in October 2003, during a period of moderate activity of the source. The spectral and temporal properties of 21 short bursts are consistent with those found in previous observations, even if these bursts are among the faintest observed in the 15-200 keV range f…

2004 • Astronomy and Astrophysics

INTEGRAL 34

A Period and a Prediction for the Of?p Spectrum Alternator HD 191612

DOI: 10.1086/427184 Bibcode: 2004ApJ...617L..61W

Corcoran, Michael F.; Walborn, Nolan R.; Bond, Howard E. +7 more

The observational picture of the enigmatic O-type spectrum variable HD 191612 has been sharpened substantially. A symmetrical, low-amplitude light curve with a period near 540 days has recently been reported from Hipparcos photometry. This period satisfies all of the spectroscopy since at least 1982, including extensive new observations during 200…

2004 • The Astrophysical Journal

Hipparcos 34

Hubble Space Telescope NICMOS Variability Study of Massive Stars in the Young Dense Galactic Starburst NGC 3603

DOI: 10.1086/425878 Bibcode: 2004AJ....128.2854M

Bergeron, E.; Moffat, A. F. J.; Marchenko, S. V. +4 more

We have used the relatively long data string of the 1997-1999 NICMOS focus tests on NGC 3603 to extract ~J-band light curves for several hundred stars in the cluster core. Given the relatively modest photometric precision [σ(J)>=0.05 mag], we were able to isolate only a half-dozen variable candidates with peak-to-valley amplitudes above ~0.2 ma…

2004 • The Astronomical Journal

eHST 34