Search Publications
Missions
Journals
Publication Years
Probing AGB nucleosynthesis via accurate Planetary Nebula abundances
Pottasch, S. R.; Tielens, A. G. G. M.; Marigo, P. +2 more
The elemental abundances of ten planetary nebulae, derived with high accuracy including ISO and IUE spectra, are analysed with the aid of synthetic evolutionary models for the TP-AGB phase. The accuracy on the observed abundances is essential in order to make a reliable comparison with the models. The advantages of the infrared spectra in achievin…
On the nature of moving magnetic feature pairs around sunspots
Solanki, S. K.; Zhang, Jun; Wang, Jingxiu
Employing data recorded by the Michelson Doppler Imager (MDI) instrument on the Solar and Heliospheric Observatory (SOHO), we have identified 144 pairs of opposite magnetic polarity moving magnetic features (MMFs) in two active regions (NOAA ARs 8375 and 9236). The following results are obtained: (1) The majority of MMF pairs first appears at a di…
Compositions of Saturn's rings A, B, and C from high resolution near-infrared spectroscopic observations
Poulet, F.; French, R. G.; Cruikshank, D. P. +2 more
We used the NASA IRTF spectrograph SpeX to obtain near-infrared spectra (0.9-5.4 mu m) of Saturn's rings, achieving spectral resolution lambda / Delta lambda of about 2000. The spatial resolution (about 1 arcsec) is sufficient to distinguish the three main ring components (A, B and C rings) from one another. These new observations of Saturn's ring…
The Internal Ultraviolet-Optical Color Dispersion: Quantifying the Morphological K-Correction
Papovich, Casey; Dickinson, Mark; Ferguson, Henry C. +2 more
We present a quantitative measure of the internal color dispersion within galaxies, which quantifies differences in galaxy morphology as a function of observed wavelength. We apply this statistic to a sample of local galaxies with archival images at 1500 and 2500 Å from the Ultraviolet Imaging Telescope and ground-based B-band observations in orde…
Gas-phase CO2 toward massive protostars
van Dishoeck, E. F.; Lahuis, F.; Doty, S. D. +1 more
We present infrared spectra of gas-phase CO2 around 15 mu m toward 14 deeply embedded massive protostars obtained with the Short Wavelength Spectrometer on board the Infrared Space Observatory. Gas-phase CO2 has been detected toward 8 of the sources. The excitation temperature and the gas/solid ratio increase with the tempera…
An EUV Bright Point as seen by SUMER, CDS, MDI and EIT on-board SoHO
Doyle, J. G.; Madjarska, M. S.; Teriaca, L. +1 more
This paper presents the formation, evolution and decay of a coronal bright point via a spectroscopic analysis of its transition region counterpart and the evolution of the underlying magnetic bipole during 3 days of almost continuous observations. The data were obtained with various instruments on-board SoHO, including the SUMER spectrograph in th…
Physical Conditions and Star Formation Activity in the Intragroup Medium of Stephan's Quintet
Lu, N.; Xu, C. K.; Tuffs, R. J. +2 more
New multiband observations of the famous compact group of galaxies Stephan's Quintet (SQ) are presented and analyzed. These include far-infrared (FIR) images at 60 and 100 µm (ISOPHOT C100 camera), radio continuum images at 1.4 GHz (VLA B configuration) and 4.86 GHz (VLA C configuration), and long-slit optical spectrographs (Palomar 200" tel…
The manifold spectra and morphologies of EROs
Cimatti, A.; Daddi, E.; Franceschini, A. +13 more
Deep VLT optical spectroscopy, HST+ACS (GOODS) imaging and VLA observations are used to unveil the nature of a complete sample of 47 EROs with R-Ks>5 and Ks<20. The spectroscopic redshift completeness is 62%. Morphological classification was derived for each ERO through visual inspection and surface brightness profile f…
A Compact X-Ray Source and Possible X-Ray Jets within the Planetary Nebula Menzel 3
Soker, Noam; Frank, Adam; Balick, Bruce +4 more
We report the discovery, by the Chandra X-Ray Observatory, of X-ray emission from the bipolar planetary nebula Menzel 3. In Chandra CCD imaging, Mz 3 displays hot [~(3-6)×106 K] gas within its twin, coaxial bubbles of optical nebulosity as well as a compact X-ray source at the position of its central star(s). The brightest diffuse X-ray…
A deep Chandra observation of the cluster environment of the z= 1.786 radio galaxy 3C 294
Fabian, A. C.; Ettori, S.; Sanders, J. S. +1 more
We report the results from a 200-ks Chandra observation of the z= 1.786 radio galaxy 3C 294 and its cluster environment, increasing by ten-fold our earlier observation. The diffuse emission, extending about 100 kpc around the nucleus, has a roughly hourglass shape in the north-south (N-S) direction with surprisingly sharp edges to the N and S. The…