Configuration Schedule for Cycle 12
The tables below indicate the anticipated configuration schedule for Cycle 12. The overall schedule may be modified depending on the outcomes of the proposal review process and the proposal pressure in the different configurations.
While configurations C-1 through C-8 (with maximum baselines between 0.16 and 8.5 km) will be offered every cycle, users should note that configurations with baselines longer than 13 km (C-9 and C-10) are scheduled for Cycle 11 but not Cycle 12.
The first column in the tables indicates the anticipated start date for each configuration. The second column gives the 12-m Array configuration, and the third column lists the longest baseline for the configuration. The fourth column lists the LST ranges when the conditions are most stable for observations, which is approximately two hours after sunset to 4 hours after sunrise.
The nominal configurations (C-1 to through C-10) refer to the configuration of all 50 antennas in the 12-m Array. Only a subset of the 50 antennas will be available for most observations due to maintenance activities, calibration observations, and testing new capabilities. In preparing simulations for proposals, users should use the "representative configurations" that assume 43 antennas are available for the observations. The CASA configuration files for the representative configurations are available through the ALMA Proposer's Guide.
During parts of the year, such as the Altiplanic winter season (January-March), it may be difficult to carry out submillimeter observations. For this reason, an extended maintenance and upgrade period is scheduled each February, during which no science observations are scheduled.
Cycle 12
Start Date | Configuration | Longest baseline | LST: Best conditions |
---|---|---|---|
1-Oct-2025 | C-8 | 8.5 km | 22-10 |
20-Oct-2025 | C-7 | 3.6 km | 23-11 |
10-Nov-2025 | C-6 | 2.5 km | 1-13 |
1-Dec-2025 | C-5 | 1.4 km | 2-14 |
20-Dec-2025 | C-4 | 0.78 km | 4-15 |
10-Jan-2026 | C-3 | 0.50 km | 5-17 |
1-Feb-2026 | No observations due to maintenance | ||
1-Mar-2026 | C-1 | 0.16 km | 8-21 |
26-Mar-2026 | C-2 | 0.31 km | 9-23 |
20-Apr-2026 | C-3 | 0.50 km | 11-0 |
10-May-2026 | C-4 | 0.78 km | 12-2 |
31-May-2026 | C-5 | 1.4 km | 13-4 |
23-Jun-2026 | C-6 | 2.5 km | 15-6 |
28-Jul-2026 | C-5 | 1.4 km | 17-7 |
18-Aug-2026 | C-4 | 0.78 km | 19-8 |
10-Sep-2026 | C-3 | 0.50 km | 20-9 |