Single-dish observing modes are available for using the Total Power (TP) Array as part of the ALMA Compact Array (ACA).

The TP Array is used to recover extended emission when mapping angular scales up to the size of the requested map areas. TP Array observations are included only if the largest angular scale (LAS) cannot be achieved with the 7-m Array, and the TP Array can only be used for spectral-line observations (not continuum) in Bands 3 through 8. No Band 1, Band 2, Band 9, or Band 10 TP Array observations are offered for this cycle. Thus, angular scales greater than the 7-m Array MRS listed in Table A-2 cannot be recovered for any observations in Bands 1, 2, 9 and 10, or for continuum observations in any band.

The TP Array cannot be requested in a stand-alone mode using the ALMA OT. However, if a user has existing 7-m Array data through their own program or through archival data, but now realizes that TP Array data are needed to obtain short spacings, they can submit a proposal requesting both the 7-m Array and TP Array. The proposal should indicate that only the TP Array is needed and that the 7-m Array should be descoped if the proposal is accepted. This option is available only if the 7-m Array data have already been obtained.

Please refer to Appendix section "Total Power Array" of the ALMA Proposer's Guide for details.