SINFONI - Integral field spectroscopy at 50 niilli-arcsecond resolution with the ESO VLT
P SOC PHOTO-OPT INS 4841 (2003) 1548-1561
Abstract:
SINFONI is an adaptive optics assisted near-infrared integral field spectrometer for the ESO VLT. The Adaptive Optics Module (built by the ESO Adaptive Optics Group) is a 60-elements curvature-sensor based system, designed for operations with natural or sodium laser guide stars. The near-infrared integral field spectrometer SPIFFI (built by the Infrared Group of MPE) provides simultaneous spectroscopy of 32 x 32 spatial pixels, and a spectral resolving power of up to 3300. The adaptive optics module is in the phase of integration; the spectrometer is presently tested in the laboratory. We provide an overview of the project, with particular emphasis on the problems encountered in designing and building an adaptive optics assisted spectrometer.SPIFFI image slicer: High-precision optics at cryogenic temperatures
P SOC PHOTO-OPT INS 4842 (2003) 375-383
Abstract:
SPIFFI is the near-infrared integral field spectrograph of the SINFONI VLT instrument. SPIFFI uses an image slicer with plane mirrors as its integral field unit. The integral field unit consists of two stacks of mirrors, each with 32 mirrors, rearranging a two-dimensional field-of-view of 32 x 32 pixels into a one-dimensional pseudo slit, which is fed into a long-slit spectrograph. The image slicer is constructed solely, from Zerodur and is operated at a cryogenic temperature of 77 Kelvin. Only optical contacting is used for the assembly of the individual slicer mirrors and the image slicer on its base-plate. The special slicer mount holds the image slicer stress-free and compensates for the different thermal coefficients of expansion of the Zerodur image slicer and the Aluminium mount. Tests at room and cryogenic temperatures show the performance of the image slicer, the durability of the optical contacting technique, and the accuracy of the slicer mount.Ultr-Luminous Infrared Galaxies: QSOs in Formation?
ArXiv astro-ph/0207405 (2002)
Abstract:
We present new near-infrared Keck and VLT spectroscopic data on the stellar dynamics in late stage, ultra-luminous infrared galaxy (ULIRG) mergers . We now have information on the structural and kinematic properties of 18 ULIRGs, 8 of which contain QSO-like active galactic nuclei. The host properties (velocity dispersion, effective radius, effective surface brightness, M_K) of AGN-dominated and star formation dominated ULIRGs are similar. ULIRGs fall remarkably close to the fundamental plane of early type galaxies. They populate a wide range of the plane, are on average similar to L*-rotating ellipticals, but are well offset from giant ellipticals and optically/UV bright, low-z QSOs/radio galaxies. ULIRGs and local QSOs/radio galaxies are very similar in their distributions of bolometric and extinction corrected near-IR luminosities, but ULIRGs have smaller effective radii and velocity dispersions than the local QSO/radio galaxy population. Hence, their host masses and inferred black hole masses are correspondingly smaller. The latter are more akin to those of local Seyfert galaxies. ULIRGs thus resemble local QSOs in their near-IR and bolometric luminosities because they are (much more) efficiently forming stars and/or feeding their black holes, and not because they have QSO-like, very massive black holes. We conclude that ULIRGs as a class cannot evolve into optically bright QSOs. They will more likely become quiescent, moderate mass field ellipticals or, when active, might resemble the X-ray bright, early type galaxies that have recently been found by the Chandra Observatory.CROMOS: A cryogenic near-infrared, multi-object spectrometer for the VLT
ESO ASTROPHY SYMP (2002) 118-127
Abstract:
We discuss a cryogenic, multi-object near-infrared spectrometer as a second generation instrument for the VLT. The spectrometer combines 20 to 40 independent integral field units (IFUs), which can be positioned by a cryogenic robot over the entire unvignetted field of the VLT (similar to 7'). Each IFU consists of a contiguous cluster of 20 to 30 pixels (0.15 to 0.25" per pixel). The individual IFUs have cold fore-optics and couple into the spectrograph with integrated fibers-microlenses. The spectrometer has resolving power of lambda/Deltalambdasimilar to4000 and simultaneously covers the J-, H-, and K-bands with three HAWAII 2 detectors. The system is designed for operation both in seeing limited and MCAO modes. Its speed is approximately 3500 times greater than that of ISAAC and 60 times greater than NIRMOS (in H-band). The proposed instrument aims at a wide range of science, ranging from studies of galaxies/clusters in the high-z Universe (dynamics and star formation in z>1 galaxies, evolution of ellipticals, properties of distant, obscured far-IR and X-ray sources), to investigations of nearby starbursts, star clusters and properties of young low mass stars and brown dwarfs.Scientific potential of enhancing the integral-field spectrometer SPIFFI with a large detector and high spectral resolution
ESO ASTROPHY SYMP (2002) 149-157