478 research outputs found
The VST telescope control software in the ESO VLT environment
The VST (VLT Survey Telescope) is a 2.6 m Alt-Az telescope to be installed at
Mount Paranal in Chile, in the European Southern Observatory (ESO) site. The
VST is a wide-field imaging facility planned to supply databases for the ESO
Very Large Telescope (VLT) science and carry out stand-alone observations in
the UV to I spectral range. This paper will focus mainly on control software
aspects, describing the VST software architecture in the context of the whole
ESO VLT control concept. The general architecture and the main components of
the control software will be described.Comment: 3 pages, 2 figures, ICALEPCS 2001 Conference, PSN#THAP05
Integration of the VIMOS control system
The VIRMOS consortium of French and Italian Institutes (PI: O. Le Fevre,
co-PI: G. Vettolani) is manufacturing two wide field imaging multi-object
spectrographs for the European Southern Observatory Very Large Telescope (VLT),
with emphasis on the ability to carry over spectroscopic surveys of large
numbers of sources: the VIsible Multi-Object Spectrograph, VIMOS, and the Near
InfraRed Multi-Object Spectrograph, NIRMOS. There are 52 motors to be
controlled in parallel in the spectrograph, making VIMOS a complex machine to
be handled. This paper will focus on the description of the control system,
designed in the ESO VLT standard control concepts, and on some integration
issues and problem solving strategies.Comment: 3 pages, 3 figures, ICALEPCS 2001 Conference, PSN#TUBT00
Pathways for Women to Obtain Positions of Organization Leadership: The Significance of Mentoring and Networking
The Atmospheric Dispersion Corrector Software for the VST
The effects of atmospheric differential refraction on astrophysical measurements are well known. In particular, as a ray of light passes through the atmosphere, its direction is altered by the effects of atmospheric refraction. The amount of this effect depends basically on the variation of the refractive index along the path of the ray. The real accuracy needed in the atmosphere model and in the calculation of the correction to be applied is of course, considerably worse, especially at large zenith angles. On the VLT Survey Telescope (VST) the use of an Atmospheric Dispersion Corrector (ADC) is foreseen at a wide zenith distance range. This paper describes the software design and implementation aspects regarding the analytical correction law discovered to correct the refraction effect during observations with VST
Software reverse engineering and development: the VST TCS case
The 2.6 m VST telescope is going to be installed at Cerro Paranal (Chile) as a powerful instrument for optical surveys. It is a joint project between the INAF - Osservatorio Astronomico di Capodimonte (OAC) and ESO. This paper deals with Telescope Control Software (TCS) technical aspects and software engineering design and development strategies
VST - VLT Survey Telescope Integration Status
The VLT Survey Telescope (VST) is a 2.6m aperture, wide field, UV to I
facility, to be installed at the European Southern Observatory (ESO) on the
Cerro Paranal Chile. VST was primarily intended to complement the observing
capabilities of VLT with wide-angle imaging for detecting and
pre-characterising sources for further observations with the VLT.Comment: 2 pages, 2 figures, conferenc
The VOICE Survey : VST Optical Imaging of the CDFS and ES1 Fields
Indexación: Scopus.We present the VST Optical Imaging of the CDFS and ES1 Fields (VOICE) Survey, a VST INAF Guaranteed Time program designed to provide optical coverage of two 4 deg2 cosmic windows in the Southern hemisphere. VOICE provides the first, multi-band deep optical imaging of these sky regions, thus complementing and enhancing the rich legacy of longer-wavelength surveys with VISTA, Spitzer, Herschel and ATCA available in these areas and paving the way for upcoming observations with facilities such as the LSST, MeerKAT and the SKA. VOICE exploits VST's OmegaCAM optical imaging capabilities and completes the reduction of WFI data available within the ES1 fields as part of the ESO-Spitzer Imaging Extragalactic Survey (ESIS) program providing ugri and uBVR coverage of 4 and 4 deg2 areas within the CDFS and ES1 field respectively. We present the survey's science rationale and observing strategy, the data reduction and multi-wavelength data fusion pipeline. Survey data products and their future updates will be released at http://www.mattiavaccari.net/voice/ and on CDS/VizieR.https://pos.sissa.it/275/026/pd
SUDARE-VOICE variability-selection of Active Galaxies in the Chandra Deep Field South and the SERVS/SWIRE region
One of the most peculiar characteristics of Active Galactic Nuclei (AGN) is
their variability over all wavelengths. This property has been used in the past
to select AGN samples and is foreseen to be one of the detection techniques
applied in future multi-epoch surveys, complementing photometric and
spectroscopic methods.
In this paper, we aim to construct and characterise an AGN sample using a
multi-epoch dataset in the r band from the SUDARE-VOICE survey.
Our work makes use of the VST monitoring program of an area surrounding the
Chandra Deep Field South to select variable sources. We use data spanning a six
month period over an area of 2 square degrees, to identify AGN based on their
photometric variability.
The selected sample includes 175 AGN candidates with magnitude r < 23 mag. We
distinguish different classes of variable sources through their lightcurves, as
well as X-ray, spectroscopic, SED, optical and IR information overlapping with
our survey.
We find that 12% of the sample (21/175) is represented by SN. Of the
remaining sources, 4% (6/154) are stars, while 66% (102/154) are likely AGNs
based on the available diagnostics. We estimate an upper limit to the
contamination of the variability selected AGN sample of about 34%, but we point
out that restricting the analysis to the sources with available
multi-wavelength ancillary information, the purity of our sample is close to
80% (102 AGN out of 128 non-SN sources with multi-wavelength diagnostics). Our
work thus confirms the efficiency of the variability selection method in
agreement with our previous work on the COSMOS field; in addition we show that
the variability approach is roughly consistent with the infrared selection.Comment: Published in A & A, 15 pages, 6 figure
Shapley Supercluster Survey (ShaSS): Galaxy Evolution from Filaments to Cluster Cores
We present an overview of a multi-wavelength survey of the Shapley
supercluster (SSC; z~0.05) covering a contiguous area of 260 h^-2_70 Mpc^2
including the supercluster core. The project main aim is to quantify the
influence of cluster-scale mass assembly on galaxy evolution in one of the most
massive structures in the local Universe. The Shapley supercluster survey
(ShaSS) includes nine Abell clusters (A3552, A3554, A3556, A3558, A3559, A3560,
A3562, AS0724, AS0726) and two poor clusters (SC1327- 312, SC1329-313) showing
evidence of cluster-cluster interactions. Optical (ugri) and near-infrared (K)
imaging acquired with VST and VISTA allow us to study the galaxy population
down to m*+6 at the supercluster redshift. A dedicated spectroscopic survey
with AAOmega on the Anglo-Australian Telescope provides a magnitude-limited
sample of supercluster members with 80% completeness at ~m*+3.
We derive the galaxy density across the whole area, demonstrating that all
structures within this area are embedded in a single network of clusters,
groups and filaments. The stellar mass density in the core of the SSC is always
higher than 9E09 M_sun Mpc^-3, which is ~40x the cosmic stellar mass density
for galaxies in the local Universe. We find a new filamentary structure (~7 Mpc
long in projection) connecting the SSC core to the cluster A3559, as well as
previously unidentified density peaks. We perform a weak-lensing analysis of
the central 1 sqdeg field of the survey obtaining for the central cluster A3558
a mass of M_500=7.63E14 M_sun, in agreement with X-ray based estimates.Comment: 22 pages, 11 figures. Accepted for publication on MNRA
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