Search Publications
Morphology and kinematics of the ionised gas in early-type galaxies
Bacon, Roland; Krajnović, Davor; Emsellem, Eric +10 more
We present results of our ongoing study of the morphology and kinematics of the ionised gas in 48 representative nearby elliptical and lenticular galaxies using the SAURON integral-field spectrograph on the 4.2m William Herschel Telescope. Making use of a recently developed technique, emission is detected in 75% of the galaxies. The ionised-gas di…
Did galaxy assembly and supermassive black-hole growth go hand-in-hand?
Ryan, R. E.; Koekemoer, A. M.; Mobasher, B. +10 more
In this paper, we address whether the growth of supermassive black-holes has kept pace with the process of galaxy assembly. For this purpose, we first searched the Hubble Ultra Deep Field (HUDF) for "tadpole galaxies", which have a knot at one end plus an extended tail. They appear dynamically unrelaxed-presumably early-stage mergers-and make up ∼…
Probing for evolutionary links between local ULIRGs and QSOs using NIR spectroscopy
Lutz, D.; Genzel, R.; Tacconi, L. J. +6 more
We present a study of the dynamical evolution of ultraluminous infrared galaxies (ULIRGs), merging galaxies of infrared luminosity >1012 L⊙. During our very large telescope large program, we have obtained ISAAC near-infrared, high-resolution spectra of 54 ULIRGs (at several merger phases) and 12 local Palomar-Green QSOs, t…
The hosts and environments of local ULIRGs and QSOs
Veilleux, Sylvain
This paper reviews the recent results from a comprehensive investigation of the most luminous mergers in the local universe, the ultraluminous infrared galaxies (ULIRGs) and the quasars. First, the frequency of occurrence and importance of black hole driven nuclear activity in ULIRGs are discussed using the latest sets of optical, near-infrared, m…
ZEN and the search for high-redshift galaxies
Kneib, Jean-Paul; Minniti, Dante; Courbin, Frédéric +1 more
We present the ZEN ( z equals nine) survey: a deep, narrow J-band search for proto-galactic Ly α emission at redshifts z ∼ 9. In the first phase of the survey, dubbed ZEN1, we combine an exceptionally deep image of the Hubble Deep Field South, obtained using a narrow-band filter centred on the wavelength 1.187 µm, with existing deep, broad b…
Spitzer observations of red galaxies: Implication for high-redshift star formation
Papovich, Casey
My colleagues and I identified distant red galaxies (DRGs) with J - Ks > 2.3 in the southern Great Observatories Origins Deep Surveys (GOODS-S) field. These galaxies reside at z ∼ 1-3.5, (< z> ≃ 2.2) and based on their ACS (0.4-1 µm), ISAAC (1-2.2 µm), and IRAC (3-8 µm) photometry, they typically have stellar …
GOODS spitzer IRAC observations of high- z galaxies - Implications for reionization
Ouchi, Masami; Papovich, Casey; Dickinson, Mark +11 more
A significant number of Lyman-break galaxies (LBGs) at z ≈ 6 and 5 in the Hubble Ultradeep Field (HUDF) have been detected by the Great Observatories Origins Deep Survey (GOODS) observations with the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. We find that the SEDs for many of these IRAC-detected high- z galaxies are best fitted b…
Studying size and physical properties of the narrow-line region in active galaxies
Haas, Martin; Chini, Rolf; Komossa, Stefanie +2 more
We explore the size and physical properties of the narrow-line region (NLR) in active galaxies via imaging and spectroscopy. From HST [OIII] images, we find striking correlations between the size and the luminosity of the NLR with different slopes for type-1 and type-2 AGNs. We show that the influence of the observers viewing angle with respect to…
Distribution of positron annihilation radiation
Milne, Peter A.
The SPI instrument on-board the ESA/INTEGRAL satellite is engaged in a mission-long study of positron annihilation radiation from the Galaxy. Early results suggest that the disk component is only weakly detected at 511 keV by SPI. We review CGRO/OSSE, TGRS and SMM studies of 511 keV line and positronium continuum emission from the Galaxy in light …
Positron production and annihilation in the Milky Way
Prantzos, Nikos
SNIa in the Milky Way bulge may supply about 12% of the positrons required by observations of the 511 keV emission from the inner Galaxy, while positrons from disk SNIa may account for the totality of that emission. It is argued here that most of the disk positrons propagate away from the disk (due to the low density environment) and the resulting…