Search Publications
A dichotomy in radio jet orientations
de Zeeuw, P. T.; Verdoes Kleijn, Gijs
We examine the relative orientations of radio jets, central dust and stars in low-power (i.e., FR I and FR I/II) radio galaxies. We use the position angles of jet and dust to constrain the three-dimensional angle θDJ between jet and dust. For galaxies with filamentary dust 'lanes' (which tend to be misaligned with the galaxy major axis)…
Unveiling hidden AGN by IR observations
Haas, Martin
AGN can be dust-hidden by two ways and this talk considers how to unveil them in the infrared: firstly, the powerful 3CR radio galaxies, i.e., type-2 AGN which suffer from anisotropic obscuration of the nuclear region by the dust torus, and secondly, type-1 quasars, which seem to be isotropically reddened by dust, so that they escape detection via…
Exploring dark energy with SNAP [review article]
Aldering, G.
The accelerating expansion of the Universe is one of the most surprising and potentially profound discoveries of modern cosmology. Measuring the acceleration well enough to meaningfully constrain interesting physical models requires improvements an order of magnitude beyond on-going and near-term experiments. The Supernova/Acceleration Probe has b…
Star formation histories in local group dwarf galaxies [review article]
Skillman, Evan D.
I review observations made with the Hubble Space Telescope which have improved our view of both recent (ages ⩽1 Gyr) and ancient (ages ⩾1 Gyr) star formation histories in dwarf galaxies. The method of reconstructing recent star formation histories has been well tested, and now the major challenge is to build a large database of suitable observatio…
Lessons from the GOODS [review article]
Giavalisco, Mauro
The Great Observatories Origins Deep Survey (GOODS) is a multi-facility project that combines data from NASA's Hubble, Chandra and Spitzer space telescopes with spectroscopy and ancillary optical and near-IR imaging from the ground (VLT, Keck, Gemini, Subaru, NOAO) to provide a database for studying galaxy and AGN evolution up to redshifts z ∼ 6.5…
Why we need wide-field imaging from space to understand galaxy formation [review article]
Somerville, R. S.
Space-based imaging with the Hubble Space Telescope has demonstrated the many advantages of viewing galaxies from outside the Earth's atmosphere. Hubble has shown us the amazing complexity of galaxies in the nearby and high redshift universe in exquisite detail. However, because of the limited areas surveyed, the sample sizes remain relatively sma…
The COSMOS 2-degree HST/ACS survey [review article]
Koekemoer, Anton M.; Scoville, Nick Z.
The COSMOS survey is the largest contiguous imaging project ever undertaken with the Hubble Space Telescope, using ACS/WFC to image a 2 square degree low-background equatorial field in 600 orbits with the F814W ( I) filter. The survey is providing over 2 million objects with a 10σ detection limit AB( I) < 27, with a sky coverage of 10 billion A…
Weak lensing studies from space with GEMS [review article]
Heymans, C.; Taylor, A. N.; Wolf, C. +16 more
The Galaxy Evolution from Morphology and SEDs (GEMS) survey is the largest contiguous field ever imaged in colour by HST with the Advanced Camera for Surveys (ACS), spanning some 900 square arcmins in the Chandra deep field south (CDFS). We discuss the power of the ACS for weak lensing studies and present preliminary results from our cosmic shear …
A review of the distance and structure of the Large Magellanic Cloud
Alves, David R.
The average of 14 recent measurements of the distance to the Large Magellanic Cloud (LMC) implies a true modulus of 18.50 ± 0.02 mag, and demonstrates a trend in the past 2 years of convergence toward a standard value. The distance indicators reviewed are the red clump, the tip of the red giant branch, Cepheid, RR Lyrae, and Mira variable stars, c…
Elemental composition and distribution in SNRs: X-ray spectroscopy
Decourchelle, A.
I present a comparative review focusing on three young Supernova Remnants, Cas A, Tycho and Kepler, in the light of recent X-ray observations obtained with the XMM-Newton and Chandra satellites. Recently available, X-ray spectro-imagery of young Supernova Remnants is providing unique information on the interaction region between the ejected materi…