Search Publications
Monte Carlo predictions of far-infrared emission from spiral galaxies
Bianchi, S.; Davies, J. I.; Alton, P. B.
We present simulations of Far Infrared (FIR) emission by dust in spiral galaxies, based on the Monte Carlo radiative transfer code of \citet*{BianchiApJ1996}. The radiative transfer is carried out at several wavelength in the Ultraviolet (UV), optical and Near Infrared (NIR), to cover the range of the stellar Spectral Energy Distribution (SED). To…
Stellar dynamics observations of a double nucleus in M 83
Genzel, R.; Thatte, N.; Tecza, M.
We report on the discovery of a double nucleus in M 83, based on measurements of the line of sight velocity distribution of stars observed at near infrared wavelengths with the VLT ISAAC spectrograph. We observe two peaks separated by 2\farcs 7 in the velocity dispersion profile of light from late-type stars measured along a slit 0\farcs 6 wide, c…
Detection of Interstellar CH3
Feuchtgruber, H.; van Dishoeck, E. F.; Helmich, F. P. +1 more
Observations with the Short Wavelength Spectrometer on board the Infrared Space Observatory have led to the first detection of the methyl radical CH3 in the interstellar medium. The ν2 Q-branch at 16.5 µm and the R(0) line at 16.0 µm have been unambiguously detected toward the Galactic center Sagittarius A*. The a…
Tomography of the Solar Corona. I. A Robust, Regularized, Positive Estimation Method
Frazin, Richard A.
A general method for the reconstruction of emissivity structures in the solar corona from projection data is presented. The method creates a robust, regularized, positive estimate (RRPE) of the coronal emissivity distribution. The problem of reconstructing the three-dimensional emissivity from a time series of coronagraph images is considered in d…
ISO-SWS spectra of the carbon stars TX Psc, V460 Cyg, and TT Cyg
Jørgensen, U. G.; Hron, J.; Loidl, R.
During our open and discretionary time ISO programs we have observed a number of carbon-rich and oxygen-rich AGB stars. We present here a hydrostatic analysis of 3 carbon rich stars, TX Psc, V460 Cyg, and TT Cyg, which show only modest variability. We identify absorption features of the molecules C_2, CN, CH, CO, CS, HCN, C_2H_2, and C_3 in the th…
NICMOS Imaging of the Damped Lyα Absorber at Z=1.89 toward LBQS 1210+1731: Constraints on Size and Star Formation Rate
Schneider, Glenn; Rieke, Marcia J.; Kulkarni, Varsha P. +5 more
We report results of a high-resolution imaging search for the galaxy associated with the damped Lyα (DLA) absorber at z=1.892 toward the zem=2.543 quasar LBQS 1210+1731, using the Hubble Space Telescope (HST) NICMOS. The images were obtained in the broad filter F160W and the narrow filter F190N with camera 2 on NICMOS and were aimed at …
Evidence of Interstellar NA I Structure at Scales Down to 15 AU in Low-Density Gas
Meyer, David M.; Blades, J. C.; Lauroesch, J. T.
We present high-resolution Hubble Space Telescope/Space Telescope Imaging Spectrograph and multiepoch KPNO coudé feed observations of multiple interstellar lines toward the binary system HD 32039/40. Comparisons of the Na I profiles observed over a period of 4.25 yr reveal significant temporal variation in the Na I column in at least one component…
New forbidden and fluorescent Fe III lines identified in HST spectra of eta Carinae
Davidson, K.; Johansson, S.; Hartman, H. +4 more
We discuss the origin of eight emission lines in the spectra of gas blobs close to the central star of eta Carinae. The spectra have been obtained with the Goddard High Resolution Spectrograph (GHRS) and the Space Telescope Imaging Spectrograph (STIS) onboard the Hubble Space Telescope. Between 2400 and 2500 Å five narrow lines are identified as n…
Determination of asteroid masses --- I. (1) Ceres, (2) Pallas and (4) Vesta
Michalak, G.
The masses of the three largest asteroids: (1) Ceres, (2) Pallas and (4) Vesta were determined from gravitational perturbations exerted on respectively 25, 2, and 26 selected asteroids. These masses were calculated by means of the least-squares method as weighted means of the values obtained separately from the perturbations on single asteroids. S…
The Surface of Titan from NICMOS Observations with the Hubble Space Telescope
Terrile, Richard J.; Smith, Bradford A.; Owen, Tobias C. +1 more
From diffraction-limited images produced by the near-IR camera NICMOS aboard the Hubble Space Telescope we derived maps of Titan's surface in the methane windows near 1.1, 1.6, and 2.0 µm. Each part of Titan's atmosphere and surface was imaged at least twice over a time period of 24 h to look for moving clouds. Despite careful analysis we fo…