Science Highlight




ALMA announces ACA observatory filler programs for Cycle 6

The ALMA Observatory announces six filler programs that have been approved on the Atacama Compact Array (ACA). The programs are designed to fill a gap in the ACA observing schedule in June/July 2019 during Cycle 6. The programs were selected based on input from scientists at the Joint ALMA Observatory (JAO) and the ALMA Regional Centers (ARCs). The proposed programs were reviewed by staff in the Department of Science Operations (DSO) at the JAO with final approval by the ALMA Director. 


The approved programs are as follows:


2017.A.00054.S: ACA Observatory Project: SMC Band 6 CO and continuum mapping
      This project will complete the Cycle 5 observatory program to obtain a large area map (~ 0.34ox 1o) of the North bar in the Small Magellanic Cloud (SMC) in 12CO(1-0), 12CO(2-1), H(30)α, and the continuum. 


2018.A.00046.S: The host properties and environment of high-redshift radio galaxies with ACA
      Over 40 high-redshift radio-AGN in the ELAIS-S1 field will be observed in the Band 6 continuum. The observations will provide a statistical understanding of radio-AGN at high redshift (z~2) and assess the star-formation activity in the local environment of these galaxies.


2018.A.00047.S: Shock-induced chemistry in the CSEs of late-type stars: a pilot study
     Band 3 and Band 6 spectral scans will be obtained for a sample of late-type stars in transition from the Asymptotic Giant Branch to the Planetary Nebula phase. The spectral survey will trace lines found in the shocked materials as well as typical lines of molecules found in circumstellar envelopes. The survey will provide the scientific community with a set of data that can pave the way for further detailed studies at higher spectral and angular resolution.


2018.A.00049.S: ACA Observatory Project: SMC Band 3 mapping
      As a complement to project 2017.A.00054.S, the North bar in the SMC will also be mapped in the 3mm transitions of CS, HCN, HCO+, H(42)α, SiO, and CCH, and the continuum. The observations will probe other emission mechanisms that occur in star forming regions and in stellar ejecta, such as free-free, hydrogen recombination lines, and dense case tracers.


2018.A.00050.T: Sgr A* Coordinated observations with Spitzer, Chandra, NuSTAR
      This project will observe the galactic center in the Band 6 or Band 7 continuum in coordination with Spitzer, Chandra, and NuStar. The ACA observations will be obtained on 3 days in July for approximately 7 hours each day. The description of the campaign is available at https://www.cfa.harvard.edu/irac/gc/.


2018.A.00051.S: Mapping Zeeman-sensitive molecules in the Orion Filament with the ACA
      Selected regions of the Orion filament will be mosaicked in Band 3 transitions of SO and CN as well as the continuum. The mosaic will identify regions that are bright in these transitions that will be suitable for follow-up Zeeman observations to measure the magnetic field strength in the filament.


The data will be quality assessed by ALMA and released through the ALMA Science Archive with no proprietary period. Observing priority will be given to any remaining Cycle 6 PI (Principal Investigator) science projects and activities to commission new capabilities on the array. In addition, starting in August 2019, ALMA will begin observing approved PI ACA Standalone projects from the Cycle 7 main call. Therefore, the above observatory programs may not be completed in full.