Performance report on FEROS, the new fiber-linked echelle spectrograph at the ESO 1.52-m telescope

FEROS is a new fiber-fed bench-mounted prism-cross dispersed echelle spectrograph which has been recently commissioned at the ESO 1.52-m telescope at La Silla. The opto-mechanical concept and performance predictions have been presented by Kaufer and Pasquini. In this contribution we present the test results as obtained during two commissioning runs in October and December 1998. Special emphasis is given to the measured performance sin efficiency, spectral resolution, straylight contamination, and spectral stability. The definite highlight of the FEROS instrument performance is the high peak detection quantum efficiency of 17 percent at 550nm. These measured numbers include the 20mirror telescope, the fiber link, the instrument, and the detector while the whole wavelength range is covered by a single exposure on a thinned EEV 2k by 4k 15 micron pixel CCD and a constant resolving power of R equals 48.000. In addition the FEROS instrument proved its high spectral stability by radial-velocity observations as carried out on the known radial-velocity standard star (tau) Ceti over a time base of 2 months. By recording a calibration-lamp spectrum in parallel with the object spectrum and by the use of a simple cross-correlation technique, a rms of 21 m/s has been obtained for a data set of 130 individual measurements. FEROS has ben made available to the ESO community in January 1999

Commissioning FEROS, the new high-resolution spectrograph at La Silla.

On November 30, 1998, the second commissioning phase of the new Fiberfed Extended Range Optical Spectrograph (FEROS) was completed at the ESO 1.52-m telescope at La Silla. The instrument had been installed by a small team from the Heidelberg, Copenhagen and La Silla observatories starting in mid-September - just two years after the contract signature between the FEROS consortium and ESO. FEROS saw its first stellar light at the end of the installation phase on October 6th. An overview of the design and of the expected capabilities of the FEROS instrument has been presented in a previous paper [Kaufer et al., 1997, The Messenger 89, 1]; a more detailed description of the opto-mechanical design is found in [Kaufer & Pasquini, 1998, Proc, SPIE Vol. 3355, p. 844]. In the present article, the major technical results from the two commissioning phases which followed the first light event are reported

Spectroscopic monitoring of the jet in the symbiotic star MWC 560

We present the results of an intensive monitoring program of the jet absorptions in the symbiotic system MWC 560, obtained with the FEROS echelle spectrograph at the ESO 1.5 m Telescope. MWC 560 is a unique jet source because the line of sight lies practically parallel to the jet axis so that the outflowing gas is seen as absorption in the continuum of the accreting object, in the emission line spectrum of the accretion disk and temporary also in the spectrum of the red giant companion. Highly variable, blue-shifted jet absorption components, due to H

The eclipsing hypergiant R 81 (B2.5Ia-O) in the Large Magellanic Cloud

The eclipsing P Cygni-type star R 81 (HDE 269128, HIP 24080) of spectral type B2.5 Ia-0 in the Large Magellanic Cloud was studied on the basis of a long continuous time series with simultaneous high-resolution Fero

High-severity and Short-interval Wildfires Limit Forest Recovery in the Central Cascade Range

Increasing forest fuel aridity with climate change may be expanding mid-to-high-elevation forests’ vulnerability to large, severe, and frequent wildfire. Long-lasting changes in forests’ structure and composition may occur if dominant tree species are poorly adapted to shifting wildfire patterns. We hypothesized that altered fire activity may lower existing forest resilience and disrupt the recovery of upper-montane and subalpine conifer forest types. We empirically tested this hypothesis by quantifying post-fire forest structure and conifer tree regeneration after spatially large, severe, and rapidly repeated wildfires

Non-radial pulsation, rotation and outburst in the Be star omega Orionis from the MuSiCoS 1998 campaign

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