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Deep Hubble Space Telescope WFPC2 Photometry of NGC 288. II. The Main-Sequence Luminosity Function

Fusi Pecci, Flavio; Rood, Robert T.; Messineo, Maria +3 more

The main-sequence luminosity function (LF) of the Galactic globular cluster NGC 288 has been obtained using deep Wide Field Planetary Camera 2 photometry. We have employed a new method to correct for completeness and fully account for bin-to-bin migration due to blending and/or observational scatter. The effect of the presence of binary systems in…

Laboratory calibration of the cassini cosmic dust analyser (CDA) using new, low density projectiles

Srama, R.; Grün, E.; Müller, M. +9 more

The Cassini Cosmic Dust Analyser (CDA), developed from the Galileo and Ulysses dust instruments with the addition of a Chemical Analyser, is currently travelling outward from the Earth (collecting data from March 1999 onward) to the Saturnian system (arrival 2004) via Jupiter. The Chemical Analyser will provide information on the elemental composi…

An Efficient Strategy to Select Targets for Gasdynamical Measurements of Black Hole Masses Using the Hubble Space Telescope

Filippenko, Alexei V.; Ho, Luis C.; Shields, Joseph C. +4 more

Gasdynamical studies using the Hubble Space Telescope are an integral component for future progress in the search for massive black holes in galactic nuclei. Here we present an extensive set of gas rotation curves obtained with the Space Telescope Imaging Spectrograph for the central regions of 23 disk galaxies. We find that the bulges of randomly…

Abundances of Planetary Nebula NGC 5315

Pottasch, S. R.; Beintema, D. A.; Feibelman, W. A. +2 more

The ISO and IUE spectra of the elliptical nebula NGC 5315 is presented. These spectra are combined with the spectra in the visual wavelength region to obtain a complete, extinction corrected, spectrum. The chemical composition of the nebulae is then calculated and compared to previous determinations. The HST NICMOS observations …

Hiding in Plain Sight: Chandra Observations of the Quiescent Neutron Star 4U 2129+47 in Eclipse

Nowak, Michael A.; Heinz, Sebastian; Begelman, M. C.

During a previous outburst phase, the neutron star 4U 2129+47 exhibited evidence for a spatially extended accretion disk corona via broad, partial X-ray eclipses occurring periodically on the 5.24 hr orbit. Since 1983, however, 4U 2129+47 has entered a quiescent state several orders of magnitude fainter. We have performed a 37 ks (~two binary orbi…

Hubble Space Telescope NICMOS Observations of the Polarization of NGC 1068

Hines, Dean C.; Schultz, A. S. B.; Trammell, Susan R. +3 more

We have observed the polarized light at 2 µm in the center of NGC 1068 with NICMOS Camera 2 on the Hubble Space Telescope. The nucleus is dominated by a bright, unresolved source, polarized at a level of 6.0%+/-1.2% with a position angle of 122^deg+/-15^deg. There are two polarized lobes extending up to 8" northeast and s…

Spatially resolved STIS spectra of the gravitationally lensed broad absorption line quasar APM08279+5255: the nature of component C and evidence for microlensing

Lewis, Geraint F.; Pettini, Max; Ellison, Sara L. +4 more

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While gravitationally lensed quasars are expected to display an odd number of images, invariably systems are observed with an even number of quasars. For this, lensing galaxies must have very small core radii; this provides strong demagnification of one of the images. High-resolution imaging of the gravitationally lensed broad absorption…

Balmer and He I Absorption in the Nuclear Spectrum of NGC 4151

Gull, T. R.; Kraemer, S. B.; Crenshaw, D. M. +4 more

Spectra taken with the Space Telescope Imaging Spectrograph allow accurate location and extraction of the nuclear spectrum of NGC 4151, with minimal contamination by extended line emission and circumnuclear starlight. Spectra since 1997 show that the P Cygni Balmer and He I absorption seen previously in low nuclear states is present in higher stat…

Hubble Space Telescope Proper Motion Confirms the Optical Identification of the Nearby Pulsar PSR 1929+10

De Luca, Andrea; Caraveo, Patrizia A.; Becker, Werner +1 more

We report on the proper-motion measurement of the proposed optical counterpart of the X-ray/radio pulsar PSR 1929+10. Using images obtained with the Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS; average epoch 2001.73), we computed a yearly displacement of +97+/-1 mas yr^-1 in right ascension and +46+/-1 mas yr<…

The Sunyaev-Zel'dovich effect as a cosmological discriminator

Diego, J. M.; Martínez-González, E.; Benitez, N. +2 more

We show how future measurements of the Sunyaev-Zel'dovich effect (SZE) can be used to constrain the cosmological parameters. We combine the SZ information expected from the Planck full-sky survey, N (S ), where no redshift information is included, with the N (z ) obtained from an optically identified SZ-selected survey covering less than 1 per cen…