1. Name: Survey of massive molecular outflows with ACA and TP only. Authors: D. Shepherd et al. 2. Science Goal: Molecular outflows from massive and intermediate-mass young stars are generally complex and are the result of the combined energetics from several OB stars and lower mass YSOs in a relatively dense cluster. The global properties of massive flow complexes is important for understanding the star formation efficiency in massive star forming regions and being able to relate galactic and extra-galactic star formation regions. Our current understanding of massive outflows is often based on CO(J=1-0 or 2-1) images that may not cover the entire outflow and that assume optically thin emission - both of these constraints can dramatically underestimate the dynamics of the outflowing gas (often by more than a factor of 10). Thus, a survey of molecular outflows from intermediate to high-mass YSOs in 12CO(J=2-1), 13CO(J=2-1), & C18O(J=2-1) (along with several other shock and high-density tracers) using the ACA combined with total power observations would provide a uniform sample with accurate estimates of outflow, dense gas, and cluster properties. Continuum observations with at least 2GHz of bandwidth will also detect embedded high- and intermediate-mass stars in the cluster that may be contributing to the outflow dynamics. If the continuum emission can be distributed between 230 & 219 GHz will be used to estimate the millimeter SED of the driving source(s). The mosaics must also be sensitive to size scales up to about 60" in the outflow. Multi-scale reconstruction of the combined uv-data will be needed to generate the final mosaic images. High resolution is NOT required at this stage. Promising candidates will be identified during this program and high-resolution and high-sensitivity follow up studies will be proposed. ************** Note: A similar survey should be contemplated for lower mass outflows. The low-mass survey should be separate from this one because: 1) The lines chosen will likely be different (fewer high density tracers) and the spectral resolution will be different. 2) The spatial resolution should be lower (e.g. low-mass outflows are generally less than a kiloparsec away, lower resolution is required match the expected size scale in the flows). 3) The continuum sensitivity will need to be higher to detect dust emission around the less luminous sources. ************** 3. Number of Sources: 20 4. Coordinates: 4.1 To be taken from a list. 4.2 Moving target: No 4.3 Time Critical: No 5. Spatial Scales: 5.1 Angular Resolution: 10" 5.2 Range of spatial scales required: 10" to 60" FOV range from 5'-20', depends on distance & source structure. 5.3 Single dish: Yes (on the ACA only) 5.4 ACA: Yes (*** NO ALMA ARRAY TIME REQUESTED ***). 5.5 Subarrays: No 6. Frequencies: 6.1 Receiver Band: 6 6.2 Lines: CO(J=2-1), 13CO(J=2-1), C18O(J=2-1) Frequencies (GHz): 230.538, 220.398, 219.560 (lines listed are the main lines of interest, other will also be observed). 6.3 Spectral Resolution (km/s): 0.3 km/s 6.4 Spectral Coverage (km/s or GHz): 100-200 km/s per line 7. Continuum flux density: 7.1 Typical Value: 0.5-10 mJy 7.2 Continuum Peak Value: Varies with source. 7.3 Required Continuum RMS: 0.3 mJy (to detect primary driving source of the flow as well as any lower-mass YSOs in the cluster) 7.4 Dynamic Range in Image: > 20 8. Line Intensity: 8.1 Typical value: > 10 Jy at 12CO line peak 10-100 mJy in high velocity wings 8.2 Required RMS per channel: 40 mJy/beam 8.3 Spectral Dynamic Range: > 10 9. Polarization: No 10. Time requested (for ACA 7m array & 12m total power dishes): Integration time per source for the ACA (interferometer and total power) (assume 4 times longer than for the ALMA array): Assuming a multi-field mosaic, 30" primary beam, 10'x10' mosaic, 4 beams/arcmin => 40x40beams = 1600 fields (just less than Nyquist spaced). 40 mJy/beam RMS in each field => 5s integration on each field (0.3 km/s resolution) => 2.5hrs total. Because fields will overlap, we will gain roughly a root 2 increase in sensitivity over the mosaic region. Integration time = 2.5/sqrt(2) hrs = 1.6 hrs times 20 sources = 32hrs total for the survey. NOTE: this is an average time, assuming all flows mapped are 10'x10', actual time estimate may differ depending on size of actual outflow fields. *********************************************************************** Review Munetake Momose: This is a plan to survey molecular outflows in massive star forming regions with (ACA + SD) only. I believe it is not appropriate to include an ACA-only program in DRSP now because the ACA is not officially included in the current project; its detailed specifications are still unclear, and its operational policy has not yet been discussed. Apart from the above issue, there are two technical problems in this plan. First, the author simply assumes that the required integration time to obtain some rms level in map with the ACA is 4 times longer than that of the ALMA. This assumption, however, is not true in this case; the factor of 4 is derived so that the uv sampling density of the ACA is nearly the same as that of the ALMA in the uv plane, so it can only be applicable when the ACA data are combined with those of the ALMA. Secondly, the ACA will consist of only 12 antennas (plus 4 12-meter antennas for the single dish mode), so "snapshot" imaging like this plan (5 sec. integration per field) will hardly be made. Comment Ewine: Put time at zero for ALMA DRSP. Program to be updated when situation on ACA and its sensitivity have been clarified.