Search Publications
ISOCAM images of the `elephant trunks' in M16
Blommaert, Joris A. D. L.; Altieri, Bruno; Pilbratt, Goeran L. +3 more
We have used ISOCAM to obtain images of the `elephant trunks' in the M16 `Eagle nebula' in the two broadband filters LW2 (5-8.5mu m) and LW3 (12-18mu m). These pillars are clearly seen in both our filters, their emission has a colour temperature in the range 250-320K. We have also detected bright extended emission in the LW3 filter, in an area out…
Corotating Particle Events
Simnett, G. M.; Kunow, H.; Horbury, T. +8 more
The corotating particle events give us a unique opportunity to probe the three-dimensional structures of the heliosphere. This is especially true if we have observations over a period of extreme stability of the CIRs, such as existed over the recent solar minimum. We discuss how the observations fit into the context of current heliospheric magneti…
A Search for Ultrarapid Microvariability in the Seyfert Galaxy NGC 7469 with the Hubble Space Telescope
Peterson, B. M.; Koratkar, A. P.; Korista, K. T. +1 more
The Faint Object Spectrograph on the Hubble Space Telescope (HST) was used to obtain spectrophotometric observations of the Seyfert 1 galaxy NGC 7469. The spectra were obtained with a 90 s time resolution in order to resolve the fastest expected variability and to search for rapid characteristic timescales (e.g., quasi-periodic oscillations or bre…
Space Telescope Imaging Spectrograph Near-Ultraviolet Time-tagged Spectra of the Crab Pulsar
Gull, Theodore R.; Lundqvist, Peter; Sonneborn, George +8 more
We present the spectrum and the pulse profile of the Crab Pulsar in the near-ultraviolet (1600-3200 Å) observed with the Space Telescope Imaging Spectrograph (STIS) during the Hubble Space Telescope (HST) second Servicing Mission Orbital Verification (SMOV) period. The two-dimensional near-ultraviolet Multianode Microchannel Array (NUV MAMA) was u…
The Probable Optical Counterpart of the Luminous X-Ray Source in NGC 6441
Anderson, Scott F.; Margon, Bruce; Deutsch, Eric W. +1 more
We report results from Hubble Space Telescope (HST)WFPC2 imaging of the field of the luminous, bursting X-ray source in the globular cluster NGC 6441. Although the X-ray position is known to a precision of a few arcseconds, this source is only ~6" from the cluster center, and the field contains hundreds of stars within the 3" X-ray error circle, m…
Ultraviolet Coronagraph Spectrometer Observations of Density Fluctuations in the Solar Wind
Romoli, M.; Poletto, G.; Noci, G. +2 more
In the Letter ``Ultraviolet Coronagraph Spectrometer Observations of Density Fluctuations in the Solar Wind'' by L. Ofman, M. Romoli, G. Poletto, G. Noci, and J. L. Kohl (ApJ, 491, L111 [1997]), there was an error in the data reduction of the polarized brightness (pB). It was assumed that the cadence of the da…
The mid infrared spectrum of the hyperluminous galaxies IRAS F15307+3252 and the Cloverleaf
Aussel, H.; Boulanger, F.; Gerin, M. +4 more
We report the detections of the hyperluminous galaxy IRAS F15307 +3252 at z = 0.93 and of the Cloverleaf quasar, H 1413+117 at z = 2.56, in the mid infrared using ISOCAM. The spectrum near 10 microns (observed wavelength) joins smoothly with the data taken from the ground or with the IRAS satellite. We have detected none of the infrared features a…
Hubble Space Telescope Observations of Planetary Nebulae in the Magellanic Clouds. VII. Cycle 3 and Archive Narrowband [O III] 500.7 nanometer Imaging
Ford, H. C.; Harrington, J. P.; Wood, P. R. +6 more
We present the continuation of our analysis of narrowband [O III] images, obtained using the Hubble Space Telescope (HST), of planetary nebulae (PNs) in the Magellanic Clouds. Six objects, five in the Large Magellanic Cloud, are observed as part of the General Observer program. An additional 15 objects are retrieved from the HST archive. The major…
Radio Emission from Young Stellar Objects near LkHα 101
Stine, Peter C.; O'Neal, Douglas
We present results of a VLA 3.6 cm B-configuration study of a region around the Herbig Be star LkHα 101. We detect 16 sources down to 5 sigma (rms) thresholds of 0.25 mJy. Most of the sources are thought to be young stellar objects associated with the star formation region. Six of the objects have optical counterparts, and at least two are weak-li…
Coronal Scale-Height Enhancement by Magnetohydrodynamic Waves
Rosner, R.; Litwin, C.
We discuss the possibility that the transmission of Alfvén waves from the photosphere into coronal loops can increase the density scale height in these loops. The mechanism involved is the ponderomotive force of transmitted waves, which opposes the force of gravity. We propose that this effect may account for cool coronal loops observed by the Sol…