Search Publications
Missions
Journals
Publication Years
SPICES II: Optical and Near-Infrared Identifications of Faint X-Ray Sources from Deep Chandra Observations of Lynx
Dey, Arjun; Rosati, Piero; Stanford, S. A. +10 more
We present our first results on field X-ray sources detected in a deep, 184.7 ks observation with the Advanced CCD Imaging Spectrometer (ACIS-I) on the Chandra X-Ray Observatory. The observations target the Lynx field (α=08h48m, δ=+44°54') of SPICES, the Spectroscopic Photometric Infrared-Chosen Extragalactic Survey, which co…
An X-Ray Investigation of the NGC 346 Field in the Small Magellanic Cloud I. The Luminous Blue Variable HD 5980 and the NGC 346 Cluster
Koenigsberger, G.; Corcoran, M. F.; Nazé, Y. +5 more
We present results from a Chandra observation of the NGC 346 cluster. This cluster contains numerous massive stars and is responsible for the ionization of N66, the most luminous H II region and the largest star formation region in the SMC. In this first paper we will focus on the characteristics of the main objects of the field. The NGC 346 clust…
Far-Infrared OH Fluorescent Emission in Sagittarius B2
Cernicharo, José; Goicoechea, Javier R.
We present Infrared Space Observatory (ISO) observations of 16OH and 18OH toward Sgr B2 with a spectral resolution of ~35 km s-1. The OH J=5/2-->3/2 and J=3/2-->1/2 rotational lines of the 2Π1/2 ladder are seen in emission, while the cross-ladder transitions (from the 2Π3…
The Descent Imager/Spectral Radiometer (DISR) Experiment on the Huygens Entry Probe of Titan
Tomasko, M. G.; Smith, P. H.; Fellows, C. +11 more
The payload of the Huygens Probe into the atmosphere of Titan includes the Descent Imager/Spectral Radiometer (DISR). This instrument includes an integrated package of several optical instruments built around a silicon charge coupled device (CCD) detector, a pair of linear InGaAs array detectors, and several individual silicon detectors. Fiber opt…
Hybrid Solar Energetic Particle Events Observed on Board Soho
Torsti, J.; Kocharov, L.
We summarize ERNE/SOHO observations of solar energetic particle events associated with impulsive soft X-ray flares and LASCO coronal mass ejections (CMEs). The new observational data support an idea that the >10 MeV proton acceleration may be initiated at different coronal sources, operating in the flaring active region and on the global corona…
Globular clusters and the Mira period-luminosity relation
Feast, Michael; Whitelock, Patricia; Menzies, John
A globular cluster distance scale based on Hipparcos parallaxes of subdwarfs has been used to derive estimates of MK for cluster Miras, including one in the Small Magellanic Cloud (SMC) globular cluster NGC 121. These lead to a zero-point of the Mira infrared period-luminosity (PL) relation, PL(K), in good agreement with that derived fr…
X-ray and optical observations of 1RXS J154814.5-452845: A new intermediate polar with soft X-ray emission
Haberl, F.; Motch, C.; Zickgraf, F. -J.
We report the identification of the ROSAT all-sky survey source
A Young Very Low Mass Object Surrounded by Warm Dust
Testi, L.; D'Antona, F.; Comoretto, G. +5 more
We present a complete low-resolution (R~100) near-IR spectrum of the substellar object GY11, a member of the ρ Ophiuchi young association. The object is remarkable because of its low estimated mass and age and because it is associated with a mid-IR source, an indication of a surrounding dusty disk. Based on the comparison of our spectrum with simi…
The stellar content, metallicity and ionization structure of H II regions
Tielens, A. G. G. M.; Peeters, E.; van der Hulst, J. M. +2 more
Observations of infrared fine-structure lines provide direct information on the metallicity and ionization structure of H Ii regions and indirectly on the hardness of the radiation field ionizing these nebulae. We have analyzed a sample of Galactic and Magellanic Cloud H Ii regions observed by the Infrared Space Observatory (ISO) to examine the in…
Detailed Spectroscopic Analysis of SN 1987A: The Distance to the Large Magellanic Cloud Using the Spectral-fitting Expanding Atmosphere Method
Pun, Chun S. J.; Baron, E.; Lundqvist, Peter +5 more
Supernova 1987A remains the most well studied supernova to date. Observations produced excellent broadband photometric and spectroscopic coverage over a wide wavelength range at all epochs. We model the observed spectra from day 1 to day 81 using a hydrodynamical model. We show that good agreement can be obtained at times up to about 60 days if we…