| 1. |
- Arnadottir, Anna, et al.
(författare)
-
The Meridian S02E03 : Instrumentation & an Aussie encounter
- 2022
-
Konstnärligt arbete (övrigt vetenskapligt/konstnärligt)abstract
- In this third episode of the second season Nic and Rebeca chat about equality in science before inviting Nikolai Piskunov to the microphone. Nikolai is a professor at the Department of Physics and Astronomy at Uppsala University. He was visiting Lund Observatory to give a talk about high-resolution transit spectroscopy and graciously agreed to make an appearance on the podcast.This season we are also bringing you some field reporting from the Nordic Optical Telescope on La Palma, where a team of astronomers are trying to catch an ultra-hot Jupiter-sized exoplanet. As the team were waiting for night to fall on the mountain Nic encountered Belinda Nicholson, who is a postdoctoral research assistant working at the University of Oxfords Astrophysics Department, where she studies both exoplanets and stellar astrophysics.
|
|
| 2. |
- Dorn, Reinhold J., et al.
(författare)
-
The " plus " for CRIRES : enabling better science at infrared wavelength and high spectral resolution at the ESO VLT
- 2016
-
Ingår i: GROUND-BASED AND AIRBORNE INSTRUMENTATION FOR ASTRONOMY VI. - : SPIE. - 9781510601963
-
Konferensbidrag (refereegranskat)abstract
- The adaptive optics (AO) assisted CRIRES instrument was a IR (0.92 - 5.2 mu m) high-resolution spectrograph in operation from 2006 to 2014 at the Very Large Telescope (VLT) observatory. CRIRES was a unique instrument, accessing a parameter space (wavelength range and spectral resolution) up to now largely uncharted. It consisted of a single-order spectrograph providing long-slit (40 arcsecond) spectroscopy with a resolving power up to R=100 000. However the setup was limited to a narrow, single-shot, spectral range of about 1/70 of the central wavelength, resulting in low observing efficiency for many scientific programmes requiring a broad spectral coverage. The CRIRES upgrade project, CRIRES, transfouns this VLT instrument into a cross-dispersed spectrograph to increase the simultaneously covered wavelength range by a factor of ten. A new and larger detector focal plane array of three Hawaii 2RG detectors with 5.3 mu m cut-off wavelength will replace the existing detectors. For advanced wavelength calibration, custom-made absorption gas cells and an etalon system will be added. A spectro-polarimetric unit will allow the recording of circular and linear polarized spectra. This upgrade will be supported by dedicated data reduction software allowing the community to take full advantage of the new capabilities. CRIRES has now entered its assembly and integration phase and will return with all new capabilities by the beginning of 2018 to the Very Large Telescope in Chile. This article will provide the reader with an update of the current status of the instrument as well as the remaining steps until final installation at the Paranal Observatory.
|
|
| 3. |
- Falster, Daniel, et al.
(författare)
-
AusTraits, a curated plant trait database for the Australian flora
- 2021
-
Ingår i: Scientific Data. - : Nature Portfolio. - 2052-4463. ; 8:1
-
Tidskriftsartikel (refereegranskat)abstract
- We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field campaigns, published literature, taxonomic monographs, and individual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised individual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge.
|
|
| 4. |
- Follert, Roman, et al.
(författare)
-
Characterizing the cross dispersion reflection gratings of CRIRES
- 2016
-
Ingår i: Advances In Optical And Mechanical Technologies For Telescopes And Instrumentation Ii. - : SPIE. - 9781510602038 - 9781510602045
-
Konferensbidrag (refereegranskat)abstract
- The CRIRES+ project attempts to upgrade the CRIRES instrument into a cross dispersed echelle spectrograph with a simultaneous recording of 8-10 diffraction orders. In order to transform the CRIRES spectrograph into a cross-dispersing instrument, a set of six reflection gratings, each one optimized for one of the wavelength bands CRIRES+ will operate in (YJHKLM), will be used as cross dispersion elements in CRIRES+. Due to the upgrade nature of the project, the choice of gratings depends on the fixed geometry of the instrument. Thus, custom made gratings would be required to achieve the ambitious design goals. Custom made gratings have the disadvantage, though, that they come at an extraordinary price and with lead times of more than 12 months. To mitigate this, a set of off-the-shelf gratings was obtained which had grating parameters very close to the ones being identified as optimal. To ensure that the rigorous specifications for CRIRES+ will be fulfilled, the CRIRES+ team started a collaboration with the Physikalisch-Technische Bundesanstalt Berlin (PTB) to characterize gratings under conditions similar to the operating conditions in CRIRES+ (angle of incidence, wavelength range). The respective test setup was designed in collaboration between PTB and the CRIRES+ consortium. The PTB provided optical radiation sources and calibrated detectors for each wavelength range. With this setup, it is possible to measure the absolute efficiency of the gratings both wavelength dependent and polarization state dependent in a wavelength range from 0.9 mu m to 6 mu m.
|
|
