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Magnetostatic Structures of the Solar Corona. III. Normal and Inverse Quiescent Prominences
Zhang, M.; Low, B. C.
Analytical solutions describing equilibrium magnetic fields in the solar corona, deformed by prominence-like plasma condensations in the Cartesian plane, are treated in this paper. The equilibrium equations for this class of problems usually take different forms in distinct subdomains, separated by free boundaries to be solved as one of the unknow…
Methane Abundance Variations toward the Massive Protostar NGC 7538 IRS 9
Blake, G. A.; Boogert, A. C. A.; Öberg, K.
Absorption and emission lines originating from the ν3 CH stretching manifold of gas-phase CH4 were discovered in the high-resolution (R=25,000) infrared L-band spectrum along the line of sight toward NGC 7538 IRS 9. These observations provide a diagnostic of the complex dynamics and chemistry in a massive star-forming region.…
Dust in Comet 67P/Churyumov-Gerasimenko
Lara, L. M.; López-Moreno, J. J.; Moreno, F. +2 more
Comet 67P/Churyumov-Gerasimenko has been designated the new target for the ESA Rosetta mission, launched successfully on 2004 March 2. We have analyzed an image set taken in 2003 March, in which the comet appeared to have a conspicuous dust antitail. We employed a Monte Carlo code, similar to that by Fulle (1989), by which we have computed the dus…
Intermittent Heating of the Solar Corona by Heat Flux-generated Ion Cyclotron Waves
Hollweg, Joseph V.; Markovskii, S. A.
Recently, we suggested that the source of ion heating in solar coronal holes is small-scale reconnection events (microflares) at the coronal base. The microflares launch intermittent heat flux up into the corona exciting ion cyclotron waves through a plasma microinstability. The ions are heated by these waves during the microflare bursts and then …
The Irradiated Herbig-Haro Jets Near σ Orionis
Bally, John; Andrews, Sean M.; Reipurth, Bo +1 more
We present high-resolution echelle spectra of the irradiated Herbig-Haro jets HH 444, 445, 446, and 447 from the Keck I telescope. The structural, kinematic, and physical properties of the jets near their sources are analyzed in detail. In particular, spatio-kinematic electron density variations and evidence for excited, low-velocity entrained mat…
XMM-Newton Spectra of Intermediate-Mass Black Hole Candidates: Application of a Monte Carlo Simulated Model
Wang, Q. Daniel; Yao, Yangsen; Fukui, Wakako +2 more
We present a systematic spectral analysis of six ultraluminous X-ray sources (NGC 1313 X-1 and X-2, IC 342 X-1, Ho IX X-1, NGC 5408 X-1, and NGC 3628 X-1) observed with the XMM-Newton observatory. These extranuclear X-ray sources in nearby late-type galaxies have been considered as intermediate-mass black hole candidates. We have performed Monte C…
The Slowly Expanding Envelope of CRL 618 Probed with HC3N Rotational Ladders
Phillips, T. G.; Cernicharo, J.; Goicoechea, J. R. +1 more
Lines from HC3N and isotopic substituted species in ground and vibrationally excited states produce crowded millimeter and submillimeter wave spectra in the C-rich protoplanetary nebula CRL 618. The complete sequence of HC3N rotational lines from J=9-8 to J=30-29 has been observed with the IRAM 30 m telescope toward this obje…
On the Temporal Relationship between Hα Filament Eruptions and Soft X-Ray Emissions
Schuck, P. W.; Chen, J.; Schwartz, I. B. +1 more
A technique for investigating the temporal relationship between Hα filament eruptions and soft X-ray flux is presented. The method is fast, simple, based on statistical measures, and requires no a priori knowledge regarding the location of the filaments on the solar disk. The method is used to study the filament eruption associated with a coronal …
Discovery of Massive Evolved Galaxies at z > 3 in the Hubble Ultra Deep Field
Chen, Hsiao-Wen; Marzke, Ronald O.
We have identified six early-type galaxies at z>2.8 in the central 5.76 arcmin2 Hubble Ultra Deep Field NICMOS region based on a pronounced broadband discontinuity between the NICMOS F110W and F160W bandpasses. These galaxies have red observed optical and near-infrared colors (ABF775W-ABF160W>=2) that cannot …
The Low- and Intermediate-Mass Stellar Population in the Small Magellanic Cloud: The Central Stars of Planetary Nebulae
Villaver, Eva; Shaw, Richard A.; Stanghellini, Letizia
We present a study on the central stars (CSs) of planetary nebulae (PNs) observed in the Small Magellanic Cloud (SMC) with the Space Telescope Imaging Spectrograph (STIS) instrument on board the Hubble Space Telescope (HST). The stellar magnitudes have been measured using broadband photometry, and Zanstra analysis of the nebulae provided the stell…