Search Publications
Missions
Journals
Publication Years
Small Polycyclic Aromatic Hydrocarbons in the Red Rectangle
Gordon, Karl D.; Witt, Adolf N.; Vijh, Uma P.
Following our initial discovery of blue luminescence in the spectrum of the Red Rectangle (RR) and its identification as fluorescence by small three- to four-ringed polycyclic aromatic hydrocarbon (PAH) molecules, we report on the spatial correlation between the blue luminescence and the 3.3 µm emission, commonly attributed to small, neutral…
The X-ray emission from Young Stellar Objects in the ρ Ophiuchi cloud core as seen by XMM-Newton.
Grosso, N.; Montmerle, T.; Ozawa, H.
We observed the main core F of the ρ Ophiuchi cloud, an active star-forming region located at d ∼ 140 pc, using XMM-Newton with an exposure of 33 ks. We detect 87 X-ray sources within the 30 arcmin diameter field-of-view of the EPIC imaging detector array. We cross-correlate the positions of XMM-Newton X-ray sources with previous X-ray, infrared (…
Inferred acoustic rates of solar p modes from several helioseismic instruments
Goupil, M. -J.; Baudin, F.; Chaplin, W. J. +5 more
Acoustic rates of excitation of solar p modes can be estimated from observations in order to place constraints on the modelling of the excitation process and the layers where it occurs in the star. For several reasons (including a poor signal to noise ratio and mode overlap), this estimation is difficult. In this work, we use three completely inde…
A Comparison of Absorption- and Emission-Line Abundances in the Nearby Damped Lyα Galaxy SBS 1543+593
Bowen, David V.; Tripp, Todd M.; Jenkins, Edward B. +1 more
We have used STIS aboard HST to measure a sulfur abundance of [S/H]=-0.41+/-0.06 in the ISM of the nearby DLA galaxy SBS 1543+593. A direct comparison between this QSO absorption line abundance and abundances measured from H II region emission line diagnostics yields the same result: the abundance of sulfur in the neutral ISM is in good agreement …
The Effect of Stellar Evolution on SiC Dust Grain Sizes
Speck, Angela K.; Thompson, Grant D.; Hofmeister, Anne M.
Stars on the asymptotic giant branch (AGB) produce dust in their circumstellar shells. The nature of the dust-forming environment is influenced by the evolution of the stars, in terms of both chemistry and density, leading to an evolution in the nature of the dust that is produced. Carbon-rich AGB stars are known to produce silicon carbide (SiC). …
A Comparative Study of the Spatial Distribution of Ultraviolet and Far-Infrared Fluxes from M101
Heckman, Timothy M.; Madore, Barry F.; Tuffs, Richard J. +23 more
The total ultraviolet (UV) flux (from 1412 to 2718 Å) of M101 is compared on a pixel-to-pixel basis with the total far-infrared (FIR) flux (from 60 to 170 µm) using the maps of the galaxy taken by the Galaxy Evolution Explorer (GALEX) in the near-UV and far-UV and by the Infrared Space Observatory (ISO) at 60, 100, and 170 µm. The main…
Abundances in the H I Envelope of the Extremely Low Metallicity Blue Compact Dwarf Galaxy SBS 0335-052 from Far Ultraviolet Spectroscopic Explorer Observations
Thuan, Trinh X.; Izotov, Yuri I.; Lecavelier des Etangs, Alain
We present Far Ultraviolet Spectroscopic Explorer spectroscopy of SBS 0335-052, the second most metal-deficient blue compact dwarf (BCD) galaxy known [log(O/H)=-4.70]. In addition to the H I Lyman series, we detect C II, N I, N II, O I, Si II, Ar I, and Fe II absorption lines, mainly arising from the extended H I envelope in which SBS 0335-052 is …
Localized fast flow disturbance observed in the plasma sheet and in the ionosphere
Balogh, A.; Lester, M.; André, M. +8 more
An isolated plasma sheet flow burst took place at 22:02 UT, 1 September 2002, when the Cluster footpoint was located within the area covered by the Magnetometers-Ionospheric Radars-All-sky Cameras Large Experiment (MIRACLE). The event was associated with a clear but weak ionospheric disturbance and took place during a steady southward IMF interval…
Oxygen Ions Observed Near Saturn's A Ring
Luhmann, J. G.; Ip, W. -H.; Mueller-Wodarg, I. +8 more
Ions were detected in the vicinity of Saturn's A ring by the Ion and Neutral Mass Spectrometer (INMS) instrument onboard the Cassini Orbiter during the spacecraft's passage over the rings. The INMS saw signatures of molecular and atomic oxygen ions and of protons, thus demonstrating the existence of an ionosphere associated with the A ring. A like…
New Silhouette Disks with Reflection Nebulae and Outflows in the Orion Nebula and M43
Smith, Nathan; Bally, John; Walawender, Josh +1 more
We report the detection of several new circumstellar disks seen in silhouette against background nebular light in the outskirts of the Orion Nebula and the neighboring H II region M43. These were detected as part of our Hα survey of Orion with the Advanced Camera for Surveys on board the Hubble Space Telescope. Several of the disks show bipolar re…