Tag: Centro Astronómico de Yebes

HEMT receivers

The 40m radio telescope at the Yebes Observatory

Outstanding publications on our innovative development

Yebes 40 m radio telescope and the broad band NANOCOSMOS receivers at 7 mm and 3 mm for line surveys (F. Tercero, J. A. López-Pérez, J. D. Gallego and 23 co-authors, A&A, 01/2021)

Breakthroughs

  • Two new cryogenic receivers for the 31.5 − 50 GHz (Q frequency band) and the 72 − 90.5 GHz (W band).
  • A new optical circuit for the W band receiver with its mirrors, new mirrors for the Q band receiver, and a new hot-cold load calibration system.
  • Instantaneous frequency coverage to observe many molecular transitions with single tunings in single dish mode: 1) Optimization of the observing time; 2) Increase in the radio telescope output efficiency; 3) Boost in data sensitivity in comparison with previous Nobeyama (Japan) 45 m telescope surveys (less than 1 mK versus 5 mK in the Nobeyama data).

Nanocosmos has developed an experimental set-up, the Gas Cell for Laboratory Astrophysics –GACELA– that operates under vacuum conditions, in order to mimick the molecular processes underlying chemical reactions of astrophysical interest. We are in particular interested in those processes occurring at the dust formation zone of AGB stars. 

We observe molecular processes in-situ by using the new NANOCOSMOS mm broad band radio astronomical receivers, which results advantageous in terms of spectral resolution and sensitivity. We have successfully applied this innovation at the 40 m radio telescope at the Yebes Observatory. Therefore, we have designed, constructed and commissioned new Q and W band receivers to foster the radio telescope capabilities and to provide wider bandwidth and better spectral resolution. The development of this instrumentation is a key aspect of the Nanocosmos project and is already providing outstanding results with the discovery of multiple molecular species.

Key Yebes internal reports to show the developments and upgrades of this instrumentation.

The project

idea

Cosmic dust is made in evolved stars. However, the processes involved in the formation and evolution of dust remain so far unknown. NANOCOSMOS will take advantage of the new observational capabilities (increased angular resolution) of the Atacama Large Millimeter/submillimeter Array (ALMA) to unveil the physical and chemical conditions in the dust formation zone of evolved stars. These observations in combination with novel top-level ultra-high vacuum experiments and astrophysical modelling will provide a cutting-edge view of cosmic dust.