Jesús Patrón

EMIR: the GTC NIR multi-object imager-spectrograph

In this contribution we review the overall features of EMIR, the NIR multiobject spectrograph of the GTC. EMIR is at present in the middle of the PD phase and will be one of the first common user instruments for the GTC, the 10 meter telescope under construction by GRANTECAN at the Roque de los Muchachos Observatory (Canary Islands, Spain). EMIR is being built by a Consortium of Spanish, French and British institutes led by the IAC. EMIR is designed to realize one of the central goals of 10m class telescopes, allowing observers to obtain spectra for large numbers of faint sources in an time-efficient manner. EMIR is primarily designed to be operated as a MOS in the K band, but offers a wide range of observing modes, including imaging and spectroscopy, both long slit and multiobject, in the wavelength range 0.9 to 2.5 μm. The present status of development, expected performances and schedule are described and discussed. This project is funded by GRANTECAN and the Plan Nacional de Astronomía y Astrofísica (National Plan for Astronomy and Astrophysics, Spain).

Structural and thermal analysis of EMIR

This paper shows the different design concepts and techniques employed in the structural and thermal analysis of EMIR (Espectrografo Multiobjeto Infrarrojo), nowadays under development at the Instituto de Astrofisica de Canarias.

EMIR mechanical design status

EMIR is the NIR multi-object imager and spectrograph for the GTC (Gran Telescopio Canarias). The instrument PDR phase was held successfully in March 2003, and we are at present in the middle of the ADR (Advanced Design Phase) during which a number of mechanical concepts will be tested on development prototypes to ensure the feasibility of the PDR proposed design. This presentation contains a technical description of the mechanical design of the instrument, as well as the prototypes development. The mechanical design is essentially built around the optical layout by providing an optical bench for mounting the optomechanics, the mechanisms and the detector, all this inside a custom-designed vacuum vessel and with the corresponding cooling system. One of its main design features is the use of a cryogenic reconfigurable slit mechanism to generate a multi-slit configuration, a long slit or an imaging aperture at the telescope focal plane. This feature will permit to maintain the instrument in operation conditions for a long time and take advantages in both a classically scheduled and a queued service observing schemes

Grisms development for EMIR

EMIR is a multiobject intermediate resolution (R ≈ 4000) near infrared spectrograph with image capabilities to be mounted on the Gran Telescopio Canarias (GTC). EMIR shall provide image and spectra of a wide FOV (6x6 arcmin in imaging mode and 6x4 arcmin in multiobject spectroscopic mode), and will use grisms as dispersive elements. The use of grisms has great advantages in the design and manufacture of infrared spectrographs but there are not many suitable materials for the EMIR requirements. The grisms material must have good transmission in the working spectral range (1.0 - 2.5 μm) and given the required resolution, a high refractive index is necessary. Also the required homogeneity of the grism material makes it difficult to find a good candidate due to the large size of the EMIR grisms. Furthermore the technical difficulties related to the grooving process on large surfaces is an important issue to be addressed. Taking into account all those constraints and the EMIR requirements, several sets of materials, rulings and dimensions have been identified. These alternative solutions for EMIR grisms are proposed and analysed in terms of their physical characteristics, expected resolution, spectral coverage on detector and diffraction efficiency. Current status of the procurement of the devices will be given.

Status of the EMIR mechanical system

EMIR is the NIR multi-object imager and spectrograph for the GTC (Gran Telescopio Canarias). The instrument ADR (Advanced Design Review) was held successfully in March 2006. During the AD phase, a number of mechanical concepts were tested on development prototypes to ensure the feasibility of the PDR proposed designs. This presentation contains an overview of the current mechanical status of the instrument, as well as the prototypes development. It contains the prototype tests results of the collimator first lens barrel, the support trusses, the grisms wheel and the demonstration programme for the cryogenic reconfigurable slit mechanism.

Status of the EMIR optical system

EMIR is a intermediate resolution near infrared (1.0 - 2.5 microns) multiobject spectrograph with image capabilities, to be mounted on the Gran Telescopio Canarias (GTC). EMIR is being built by a consortium of Spanish, French and British institutions, led by the Instituto de Astrofísica de Canarias. EMIR is being funded by GRANTECAN and the Plan Nacional de Astronomía y Astrofísica (National Plan for Astronomy and Astrophysics, Spain) as one of the first common user instruments for the GTC. The instrument shall deliver images and spectra from a large FOV (6x6 arcmin in imaging mode, and 6x4 arcmin in multislit spectroscopic mode). Due to the telescope image scale (1 arcmin = 52 mm) and the spectral resolution required (around 4000), one of the major challenges of the instrument is the optical design and the manufacture. The detailed optical design and its expected performance will be presented. In particular the main risk areas will be identified and our risk control strategy will be outlined.

EMIR, cryogenic NIR multi-object spectrograph for GTC

EMIR is a near-IR, multi-slit camera-spectrograph under development for the 10m GTC on La Palma. It will deliver up to 45 independent R equals 3500-4000 spectra of sources over a field of view of 6 feet by 3 feet, and allow NIR imaging over a 6 foot by 6 foot FOV, with spatial sampling of 0.175 inch/pixel. The prime science goal of the instrument is to open K-band, wide field multi-object spectroscopy on 10m class telescopes. Science applications range from the study of star-forming galaxies beyond z equals 2, to observations of substellar objects and dust-enshrouded star formation regions. Main technological challenges include the large optics, the mechanical and thermal stability and the need to implement a mask exchange mechanism that does not require warming up the spectrograph. EMIR is begin developed by the Instituto de Astrofisica de Canarias, the Instituto Nacional de Tecnica Aeroespacial, the Universidad Complutense de Madrid, the Observatoire Midi-Pyrennees, and the University of Durham. Currently in its Preliminary Design phase, EMIR is expected to start science operation in 2004.

FRIDA, the diffraction limited NIR imager and IFS for the Gran Telescopio Canarias: status report

FRIDA is a diffraction limited imager and integral field spectrometer that is being built for the Gran Telescopio Canarias. FRIDA has been designed and is being built as a collaborative project between institutions from México, Spain and the USA. In imaging mode FRIDA will provide scales of 0.010, 0.020 and 0.040 arcsec/pixel and in IFS mode spectral resolutions R ~ 1000, 4,500 and 30,000. FRIDA is starting systems integration and is scheduled to complete fully integrated system tests at the laboratory by the end of 2015 and be delivered to GTC shortly after. In this contribution we present a summary of its design, fabrication, current status and potential scientific applications.

EMIR: THE GTC NIR MULTI-OBJECT IMAGER-SPECTROGRAPH

no nal global y el desempe~ de EMIR, el espectr ografo para objetos m ultiples del NIR del GTC, como tambi en el plan para su aplicaci on cient ca inicial. EMIR, actualmente en sus fases nales, ser a uno de los primeros instrumentos para usuarios del GTC, el telescopio de 10 metros en construcci on por GRANTECAN en el Observatorio del Roque de los Muchachos (Islas Canarias, Espa~ A EMIR lo construye un consorcio de institutos espa~ y franceses conducido por IAC. EMIR est a dise~ para llevar a cabo uno de los objetivos centrales de los telescopios de la clase de 10 metros, lo que permitir a a los observadores obtener espectros de gran n umero de objetos d ebiles de una manera ecien te en cuanto al tiempo. EMIR est a dise~ para ser operado primariamente como un MOS en la banda K, pero ofrece adem as un amplio rango de modos observacionales, incluido imagen y espectroscop a, tanto de rendija larga como de objetos m ultiples, en el rango de longitudes de onda de 0.9 a 2.5 m. Se encuentra equipado con dos subsistemas novedosos: una m ascara de rendijas m ultiples rob otica recongurable y elementos dispersivos formados por una combinaci on de rejilla de difracci on y prismas convencionales de alta calidad, ambos localizados en el coraz on del instrumento. Se describe y discute el estado actual de desarrollo, el desempe~ esperado, el calendario y los planes de aplicaci on cient ca. Este proyecto est a nanciado mayormente por GRANTECAN y el Plan Nacional de Astronom a y Astrof sica de Espa~ na.

EMIR and OSIRIS instruments: common data acquisition software architecture

OSIRIS (Optical System for Imaging and low/intermediate-Resolution Integrated Spectroscopy) and EMIR (InfraRed MultiObject Spectrograph) are instruments designed to obtain images and low resolution spectra of astronomical objects in the optical and infrared domains. They will be installed on Day One and Day Two, respectively, in the Nasmyth focus of the 10-meter Spanish GTC Telescope. This paper describes the architecture of the Data Acquisition System (DAS), emphasizing the functional and quality attributes. The DAS is a component oriented, concurrent, distributed and real time system which coordinates several activities: acquisition of images coming from the detectors controller, tagging, and data communication with the required telescope system resources. This architecture will minimize efforts in the development of future DAS. Common aspects, such as the data process flow, concurrency, asynchronous/synchronous communication, memory management, and exception handling, among others, are managed by the proposed architecture. This system also allows a straightforward inclusion of variable parts, such as dedicated hardware and different acquisition modes. The DAS has been developed using an object oriented approach and uses the Adaptive Communication Environment (ACE) to be operating system independent.