Search Publications
The Optical Gravitational Lensing Experiment Monitoring of QSO 2237+0305
Alard, C.; Udalski, A.; Woźniak, P. R. +4 more
We present results from 2 yr of monitoring of Huchra's lens (QSO 2237+0305) with the 1.3 m Warsaw telescope on Las Campanas, Chile. Photometry in the V band was done using a newly developed method for image subtraction. Reliable subtraction without Fourier division removes all complexities associated with the presence of a bright lensing galaxy. W…
Double-peaked Broad Emission Lines in NGC 4450 and Other LINERS
Filippenko, Alexei V.; Ho, Luis C.; Shields, Joseph C. +5 more
Spectra taken with the Hubble Space Telescope (HST) reveal that NGC 4450 emits Balmer emission lines with displaced double peaks and extremely high velocity wings. This characteristic line profile, previously seen in a few nearby LINERs and in a small fraction of broad-line radio galaxies, can be interpreted as a kinematic signature of a relativis…
Extreme Star Formation in the Interacting Galaxy Arp 299 (IC 694+NGC 3690)
Rieke, George H.; Alonso-Herrero, Almudena; Rieke, Marcia J. +1 more
We present a comprehensive study of the star formation properties of the infrared luminous galaxy Arp 299 (IC 694+NGC 3690). The observations include Hubble Space Telescope (HST) NICMOS imaging and Multiple Mirror Telescope optical and near-infrared spectroscopy together with HST archival data. We correct the galaxy parameters for extinction and u…
Effects of massive star formation on the ISM of dwarf galaxies
Madden, Suzanne C.
We are studying star formation effects on the properties of the ISM in low metallicity environments using mid-infrared (MIR) and far-infrared (FIR) observations of starbursting dwarf galaxies taken with the Infrared Space Observatory (ISO) and the Kuiper Airborne Observatory (KAO). Effects of the hard pervasive radiation field on the gas and dust …
The anomalous Galactic globular cluster NGC 2808. Mosaic wide-field multi-band photometry
Zoccali, M.; Stetson, P. B.; Bedin, L. R. +4 more
We present Johnson UBV, and Kron-Cousins I photometry for about 60,000 stars in a region of 44x33 arcmin2 centered on the Galactic globular cluster (GGC) NGC 2808. The central r<100 arcsec region has been mapped also in the F218W, F439W, and F555W bands with the HST WFPC2 camera. Overall, we cover a field which extends from the cente…
2-45 Micron Infrared Spectroscopy of Carbon-rich Proto-Planetary Nebulae
Volk, Kevin; Kwok, Sun; Hrivnak, Bruce J.
Infrared Space Observatory (ISO) 2-45 µm observations of seven proto-planetary nebulae (PPNs) and two other carbon-rich objects are presented. The unidentified emission features at 21 and 30 µm are detected in six sources, including four new detections of the 30 µm feature. This previously unresolved 30 µm feature is now re…
Evidence for Multiple Mergers among Ultraluminous Infrared Galaxies: Remnants of Compact Groups?
Lucas, Ray A.; Colina, Luis; Bushouse, Howard +1 more
In a large sample of ultraluminous infrared galaxies (ULIRGs) imaged with the Hubble Space Telescope, we have identified a significant subsample that shows evidence for multiple mergers. The evidence is seen among two classes of ULIRGs: (1) those with multiple remnant nuclei in their core, sometimes accompanied by a complex system of tidal tails, …
ISO-SWS Observations of Jupiter: Measurement of the Ammonia Tropospheric Profile and of the 15N/ 14N Isotopic Ratio
Drossart, Pierre; Bézard, Bruno; Lellouch, Emmanuel +4 more
We present the results of the Infrared Space Observatory Short Wavelength Spectrometer (ISO-SWS) observations of Jupiter related to ammonia. We focus on two spectral regions; the first one (the 10-µm region), ranging from 9.5 to 11.5 µm, probes atmospheric levels between 1 and 0.2 bar, while the second one (the 5-µm window), rang…
On the evolution of outward and inward Alfvénic fluctuations in the polar wind
Bavassano, B.; Pietropaolo, E.; Bruno, R.
Plasma and magnetic field measurements by Ulysses are used to investigate the radial evolution of hourly-scale Alfvénic fluctuations in the polar wind. The data span from 1.4 to 4.3 AU in heliocentric distance. Different radial regimes at different distances emerge. Inside about 2.5 AU the large outward traveling fluctuations decrease faster, in t…
Hubble Space Telescope WFPC2 Imaging of a Sample of Early-Type Seyfert Galaxies
Ferruit, Pierre; Mulchaey, John; Wilson, Andrew S.
We have defined a complete sample comprising all 14 Seyfert galaxies in early-type (E, S0, Sa) host galaxies with apparent magnitude mv<14.5 mag and recessional velocity cz<3000 km s-1. This paper presents Hubble Space Telescope (HST) imaging observations of 12 of them, the other two having been observed previously with…