Science Archives Publication System

The dynamical evolution of the fragmented, bipolar dust shell around the carbon star IRC +10 216 . Rapid changes of a PPN-like structure?

DOI: 10.48550/arXiv.astro-ph/0003328 Bibcode: 2000A&A...357..169O

Weigelt, G.; Men'shchikov, A. B.; Blöcker, T. +2 more

We present high-resolution J-, H-, and K-band observations and the first H-K color image of the carbon star IRC +10 216. The images were reconstructed from 6 m telescope speckle interferograms using the bispectrum speckle interferometry method. The H and K images with resolutions between 70 mas and 92 mas consist of several comp…

2000 • Astronomy and Astrophysics

eHST 43

Stellar Populations in the Phoenix Dwarf (DIRR/DSPH) Galaxy as Observed by Hubble Space Telescope WFPC2

DOI: 10.1086/316844 Bibcode: 2000AJ....120.3060H

Grillmair, Carl; Smith, Graeme H.; Holtzman, Jon A.

We present Hubble Space Telescope Wide Field Planetary Camera 2 photometry of the central regions of the Phoenix dwarf galaxy. Accurate photometry allows us to (1) confirm the existence of the horizontal branch previously detected by ground-based observations and use it to determine a distance to Phoenix, (2) clearly detect the existence of multip…

2000 • The Astronomical Journal

eHST 43

Circumnuclear structure and kinematics in the active galaxy NGC 6951

DOI: 10.48550/arXiv.astro-ph/9909495 Bibcode: 2000A&A...353..893P

Durret, F.; González Delgado, R. M.; Moles, M. +5 more

A study is presented of the central structure and kinematics of the galaxy NGC 6951, by means of broad band B{\arcminIJK} images and high resolution high dispersion longslit spectroscopy, together with archival HST WFPC2 V and NICMOS2 J and H images. We find that there is little ongoing star formation inside the bar dominated region of the galaxy,…

2000 • Astronomy and Astrophysics

eHST 43

Observations of sunspot transition region oscillations

DOI: 10.1023/A:1005279321373 Bibcode: 2000SoPh..191..129B

Wilhelm, K.; Kjeldseth-Moe, O.; Brynildsen, N. +2 more

Oscillations with a period of 3 minutes are observed in the transition region of six sunspots with the Solar and Heliospheric Observatory - SOHO joint observing programme for velocity fields in sunspot regions. Observations of the transition region lines O v λ629 and N v λλ1238, 1242 with the SUMER instrument show significant differences in the am…

2000 • Solar Physics

SOHO 42

Analysis of the Hipparcos Measurements of HD 10697: A Mass Determination of a Brown Dwarf Secondary

DOI: 10.1086/312523 Bibcode: 2000ApJ...531L..67Z

Mazeh, Tsevi; Zucker, Shay

HD 10697 is a nearby main-sequence star around which a planet candidate has recently been discovered by means of radial velocity measurements (Vogt et al.). The stellar orbit has a period of about 3 yr, the secondary minimum mass is 6.35 Jupiter masses (M_J), and the minimum semimajor axis is 0.36 mas. Using the Hipparcos data of HD 1069…

2000 • The Astrophysical Journal

Hipparcos 42

The Pleiades, Map-based Trigonometric Parallaxes of Open Clusters. V.

DOI: 10.1086/308679 Bibcode: 2000ApJ...533..938G

Han, Inwoo; Gatewood, George; de Jonge, Joost Kiewiet

The Multichannel Astrometric Photometer and Thaw Refractor (Thaw/MAP) of the University of Pittsburgh's Allegheny Observatory have been used to determine the trigonometric parallax of the Pleiades star cluster. The parallax determined, 0.00764" with a standard error of +/-0.00043" (corresponding to a distance modulus of 5.59+/-0.12 mag) places the…

2000 • The Astrophysical Journal

Hipparcos 42

Sensitivity of the GOLF signal to combined solar velocity and intensity variations

Bibcode: 2000A&A...364..799U

García, R. A.; Turck-Chièze, S.; Dzitko, H. +6 more

The GOLF instrument provides a stable and continuous measurement of the intensity of spatially integrated sunlight in one wing of the sodium D lines. Because the detected radiation results from atomic scattering, the GOLF signal can be traced to an atomic reference wavelength. The planned operations were to involve a form of relative photometry th…

2000 • Astronomy and Astrophysics

SOHO 42

Discovery of Parsec-sized Dust Shells around AFGL 2688 and AFGL 618

DOI: 10.1086/317881 Bibcode: 2000ApJ...545L.145S

Meixner, M.; Knapp, G. R.; Speck, A. K.

We present ISOPHOT linear scans of two carbon-rich proto-planetary nebulae, AFGL 2688 and AFGL 618. The 53^'×3^' scans were made with the ISO AOT PHT32 using the 120 and 180 µm filters. Both these objects appear to have very bright central point sources together with extremely extended (radius ~350"-400") dust shells with…

2000 • The Astrophysical Journal

ISO 42

The Hubble Deep Field South: STIS Imaging

DOI: 10.1086/301215 Bibcode: 2000AJ....119..486G

Ferguson, Henry C.; Baum, Stefi A.; Brown, Thomas M. +18 more

We present the imaging observations made with the Space Telescope Imaging Spectrograph (STIS) of the Hubble Deep Field South. The field was imaged in four bandpasses: a clear CCD bandpass for 156 ks, a long-pass filter for 22-25 ks pixel^-1 typical exposure, a near-UV bandpass for 23 ks, and a far-UV bandpass for 52 ks. The clear, visibl…

2000 • The Astronomical Journal

eHST 42

Calibrating Array Detectors

DOI: 10.1086/313390 Bibcode: 2000ApJS..128..651F

Fixsen, D. J.; Arendt, R. G.; Moseley, S. H.

The development of sensitive large-format imaging arrays for the infrared promises to provide revolutionary capabilities for space astronomy. For example, the Infrared Array Camera (IRAC) on SIRTF will use four 256×256 arrays to provide background limited high spatial resolution images of the sky in the 3 to 8 µm spectral region. In order to…

2000 • The Astrophysical Journal Supplement Series

eHST 42