Introducing the new Policy for Guaranteed Time Observations on ALMA

Published: 20 Dec 2021

At the most recent meeting, in December 2021, ESO Council approved a new Guaranteed Time Observations (GTO) policy for ALMA. In exchange for contributions to the ALMA development programme, the new policy allows institutes to access the European regional share of ALMA time. The policy thus aims to incentivise R&D institutes in the ESO member states to contribute to the ALMA development programme, leading to increased investment in the ALMA facility, which will in turn provide significant improvements in bandwidth, sensitivity, etc., for all users. In other words, the policy seeks to replicate for ALMA the model that has been so successful for the development and upgrade of instrumentation on ESO's optical and infrared telescopes.

For those concerned about the impact of this new policy on an already heavily over-subscribed facility, it should be noted that the policy includes a cap of 10% of the total amount of time available to the EU region. Time allocations associated with the first GTO awards will take some years to materialise, and will be unlikely to exceed 1% of the European regional share for several years thereafter. The benefits that will accrue from the increased sensitivity associated with the extra investment in the facility are expected to heavily outweigh this modest reduction in time available to the community.

As with the model used at the La Silla Paranal Observatory, and that in place for ELT, GTO proposals will be submitted to the regular proposal review process, and will need to meet scientific and technical thresholds in order to be scheduled on the telescope. 

More information can be found in the GTO policy document.