Science Highlight




ALMA Cycle 2 Pre-announcement

The Joint ALMA Observatory (JAO) expects to start the next cycle of Early Science observations (Cycle 2) in June 2014. A Call for Proposals will be issued at the end of October 2013, with an anticipated deadline for proposal submission in early December 2013. Cycle 2 operations will be conducted on a best efforts basis, similar to the current Cycle 1 and the past Cycle 0 observations.

While the highest priority of the ALMA project continues to be the completion of the full 66-antenna array, Cycle 2 observations provide an exciting opportunity for science from this unique world-class facility.

Detailed information on Cycle 2 will be published in the Call for Proposals.

General information

ALMA Early Science Cycle 2 is expected to start in June 2014 and to span 17 months. During this period a significant amount of time will be reserved for engineering and commissioning work to realize the full suite of ALMA capabilities. It is anticipated that approximately 2000 hours of both 12-m Array and ACA (Atacama Compact Array – also called the Morita Array) time will be available for those Cycle 2 proposals that are assigned highest priority based on their scientific ranking by the ALMA Proposal Review Committee.

Any astronomer may submit a proposal in response to the ALMA Early Science Cycle 2 Call for Proposals. Successful proposers will share risk with ALMA: it cannot be guaranteed that projects will be completed or that the characterization and quality of the data and data reduction will meet the standards expected when ALMA is in full scientific operations. ALMA staff will conduct quality assurance on the data, and will provide reduced data products through the respective ALMA Regional Centers (ARCs).

A status report on Cycle 1 will be published on the Science Portal in early October. It will include an assessment of the completion likelihood of Cycle 1 projects.

A high-level principle of ALMA is that identical data should not be taken twice unless scientifically necessary. Submitted proposals will be checked for duplication against successful Cycle 1 projects, but will not be checked against Cycle 0 projects. The definition of duplications will appear in the Cycle 2 Call materials, but will be similar to that given in the Cycle 1 Proposers Guide. The Proposal Review Committee will be asked to make clear recommendations regarding potential duplications.

Notices of Intent

To help ensure that the Observatory is prepared to assess the proposals submitted for Cycle 2, Principal Investigators are strongly encouraged to submit a notice of intent by 15:00 UT on October 10 using the following web form . One form should be completed and submitted for each planned Cycle 2 proposal. This should not require more than a few minutes since the information to be provided is minimal. Notices of Intent are neither mandatory nor binding.

Anticipated Capabilities

Detailed information on Cycle 2 capabilities will be published in the Call for Proposals. As of the date of this pre-announcement, the ALMA Early Science Cycle 2 anticipated capabilities comprise:

  • Thirty four 12-m antennas in the main array (12-m Array), and  nine 7-m antennas (7-m Array, for short baselines) and two 12-m antennas (Total Power Array or TP Array, for making single-dish maps), which together constitute the Atacama Compact Array
  • Receiver bands 3, 4, 6, 7, 8 & 9 (wavelengths of about 3.1, 2.1, 1.3, 0.87, 0.74 and 0.44 mm)
  • Both single field interferometry and mosaics
  • Spectral-line observations with all Arrays and continuum observations with the 12-m Array and the 7-m Array.
  • Polarization (on-axis, continuum, selected frequencies in Band 3, 6 and 7, no ACA, no mosaics)
  • Mixed correlator modes (both high and low frequency resolution in the same observation)
  • Baselines up to 1 km for Bands 8 & 9
  • Baselines up to 1.5 km for Bands 3, 4, 6, & 7


Use of the ACA for short baseline interferometry and single-dish observations will only be offered to complement observations with the 12-m Array, and not as a stand-alone capability. Single dish use will be limited to spectral line observations in Bands 3 to 8.

The number of array elements available for science observing is less than the number available overall. This is because some of them must be reserved to commission the full science observing modes (additional receiver bands, longer baselines etc).

Key dates

The key dates for Cycle 2 are given below. ALMA reserves the right to alter the given dates, should it become necessary to do so.

  • Early October 2013: Publication of Cycle 1 status report on the Science Portal.
  • 10 October 2013, 15:00 UT: Deadline for Notices of Intent.
  • 24 October 2013: Call for Proposals for ALMA Early Science Cycle 2, release of Observing Tool, and opening of Archive for proposal submission.
  • 5 December 2013: Proposal Deadline.
  • Mid April 2014: Result of the proposal review process sent to PIs.
  • June 2014: Start of ALMA Cycle 2 observing.
  • October 2015: End of ALMA Cycle 2 observing.