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When I submit proposals, to which region will the time be charged? - Knowledgebase / General ALMA Queries - ALMA Science

When I submit proposals, to which region will the time be charged?

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Users of any professional background, nationality or affiliation may submit an ALMA proposal. All proposals are reviewed without regard to the nationalities or affiliations of the investigators.

Successful projects will have their observing time assigned to the region of the PI, which is defined as the region to which the organization that employs the PI belongs, or as the region of residence for unaffiliated PIs. If a PI has access to ALMA through two regions (e.g. due to a joint appointment at organizations in different regions), the PI may select either as his/her affiliation. Users from Taiwan (which is affiliated with both EA and NA) will be able to select either an EA, NA or combined EA/NA affiliation (with 50% of the time accounted to each region) in the OT on a proposal-by-proposal basis.

The observing time of Large Proposals will be assigned to the regions of the PI and of the Co-PIs, proportionally to the fraction that are affiliated with each region. 

ALMA policies prohibit multiple submissions of the same proposal using different Executive affiliations. If such proposals are detected, the first submitted version will be considered and the remaining proposals ignored. 

By international agreement, ALMA time is shared between the three Executives (NA, EU, and EA) and Chile in the following proportions:


East Asia (EA)


Europe (EU)


North America (NA)



ALMA proposals may also be submitted by PIs whose affiliation does not lie within any ALMA Executive’s region (EA, EU, NA or Chile). Such proposals are referred to as “Open Skies” proposals. Time for “Open Skies” proposals will be shared between the four ALMA regions in the proportions listed above.


The policies of time accounting is described in the Principles of Proposal Review Process document in the ALMA Science Portal.


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