Automatization of a multipurpose astronomical spectrograph

5 pages, 7 figures.This article deals with the study and fabrication of a system for the automation of a multipurpose spectrograph used in Astronomy. This system allows the 19 movements of the instrument to run by using high-level software, a "master" board, and 19 "slave" boards. The Astrophysique Lineal et BIdimensional par RÉseaux Optiques (ALBIREO) spectrograph has three working modes and is installed in the Observatorio de Sierra Nevada, Granada, Spain. We describe a low-cost system realized for the automatization of a multifunction spectrograph. It allows the control of a large number of motors: 19 for Albireo; the theoretical limit is 32 768! Another advantage of this architecture based on "slave" boards is to supply each motor with exactly the current it needs to reach the required torque (reliability and repetitivity of motions are obtained when the motor torque is at least twice the resistant torque). Thus, we can avoid unnecessary overheating which would be detrimental to the material as well as to the local image quality (seeing). The reliability of the system is obtained by software filtering the commands and also by using optocoupled electronics to avoid interference. For a complex instrument, the high-level software must be user friendly. The efficiency of the present software in this respect has been appreciated since first being used on the telescope. This system may be of interest to laboratories and observatories with similar needs for automation of motions. The adoption of this system will be supported by the IAA Laboratory, Granada, Spain.The development was financially supported by the Instituto de Astrofisica de Andalucia, from the CSIC, Granada, Spain.Peer reviewe

Web services as building blocks for science gateways in astrophysics

An efficient exploitation of Distributed Computing Infrastructures (DCIs) is needed to deal with the data deluge that the scientific community is facing, in particular the Astrophysics one due to the emerging Square Kilometre Array (SKA) telescope that will reach data rates in the exascale domain. Hence, Science Gateways are being enriched with advanced tools that not only enable the scientists to build their experiments but also to optimize their adaptation to different infrastructures. In this work we present a method, called “two-level workflow system”, to build this kind of tools and we apply it to a set of analysis tasks of interest for some use applications to the SKA. This method uses the Software-as-a-Service model to keep the scientists insulated from technical complexity of DCIs, and the COMPSs programming model to achieve an efficient use of the computing resources. © 2016, Springer Science+Business Media Dordrecht.This work has been developed in the framework of AMIGA4GAS (AYA2011-30491-C02) and AMIGA5 (AYA2014-52013-C2-1-R), co-funded by MICINN and FEDER funds. It has been also supported by the Wf4Ever STREP Project (270129) funded under EU FP7 (ICT-2009.4.1) and the Galaxias y Cosmologia project funded by the Junta de Andalucia (TIC-114). This work has also benefited from IBERGRID and the EGI Federated Cloud.Peer reviewe