4 research outputs found
Concept and optical design of the cross-disperser module for CRIRES
This is the peer reviewed version of the following article: Oliva, Ernesto, A. Tozzi, D. Ferruzzi, L. Origlia, A. Hatzes, R. Follert, T. Loewinger et al. "Concept and optical design of the cross-disperser module for CRIRES+." In SPIE Astronomical Telescopes+ Instrumentation, pp. 91477R-91477R. International Society for Optics and Photonics, 2014, which has been published in final form at 10.1117/12.2054381
The signature of orbital motion from the dayside of the planet tau Bootis b
The giant planet orbiting tau Bootis was among the first extrasolar planets
to be discovered through the reflex motion of its host star. It is one of the
brightest known and most nearby planets with an orbital period of just a few
days. Over the course of more than a decade, measurements of its orbital
inclination have been announced and refuted, and have subsequently remained
elusive until now. Here we report on the detection of carbon monoxide
absorption in the thermal day-side spectrum of tau Bootis b. At a spectral
resolution of R~100,000, we trace the change in the radial velocity of the
planet over a large range in phase, determining an orbital inclination of
i=44.5+-1.5 degrees and a true planet mass of 5.95+-0.28 MJup. This result
extends atmospheric characterisation to non-transiting planets. The strong
absorption signal points to an atmosphere with a temperature that is decreasing
towards higher altitudes. This is a stark contrast to the temperature inversion
invoked for other highly irradiated planets, and supports models in which the
absorbing compounds believed to cause such atmospheric inversions are destroyed
by the ultraviolet emission from the active host star.Comment: To appear in the June 28 issue of Nature: main article +
supplementary informatio
Technetium and lithium in Galactic bulge AGB stars (vol 463, pg 251, 2007)
Nonestatus: publishe
CRIRES plus : a cross-dispersed high-resolution infrared spectrograph for the ESO VLT
High-resolution infrared spectroscopy plays an important role in astrophysics from the search for exoplanets to cosmology. Yet, many existing infrared spectrographs are limited by a rather small simultaneous wavelength coverage. The AO assisted CRIRES instrument, installed at the ESO VLT on Paranal, is one of the few IR (0.92-5.2 μm) highresolution spectrographs in operation since 2006. However it has a limitation that hampers its efficient use: the wavelength range covered in a single exposure is limited to ~15 nanometers. The CRIRES Upgrade project (CRIRES+) will transform CRIRES into a cross-dispersed spectrograph and will also add new capabilities. By introducing crossdispersion elements the simultaneously covered wavelength range will be increased by at least a factor of 10 with respect to the present configuration, while the operational wavelength range will be preserved. For advanced wavelength calibration, new custom made absorption gas cells and etalons will be added. A spectro-polarimetric unit will allow one for the first time to record circularly polarized spectra at the highest spectral resolution. This will be all supported by a new data reduction software which will allow the community to take full advantage of the new capabilities of CRIRES+