Title The energetics and temperature structure of protostellar outflows Pi H. G. Arce Time 840 hrs DRSP 2.0 - section 2.2 proposal 1. Name of program and authors Name: The energetics and temperature structure of protostellar outflows Author: H. G. Arce, et al. 2. One short paragraph with science goal(s) Protostellar outflows interact with their gaseous surroundings, injecting momentum and energy into their parent molecular cloud. The interaction between the outflow and the cloud could play a crucial role in the chemical composition of the gas (e.g., Jorgensen et al. 2004), the turbulence of the cloud (e.g., Williams et al. 2003; Li & Nakamura 2006) and the cloud's velocity and density distribution (Arce & Goodman 2001;2002). Morphology and velocity structure are two relatively well-studied physical characteristics of molecular outflows. On the other hand, the energetics and temperature structure of outflows have been rarely studied. Further studies of outflow energetics are needed in order to fully understand the outflow phenomenon, its impact on the parent cloud, and the entrainment mechanism (e.g., Hatchell et al. 1999). We plan to observe all the 12CO and 13CO transitions accessible to ALMA in order to use line ratios to study the temperature distribution of the high-velocity outflow gas and to better understand how protostellar winds heat and impact their surroundings. We will obtain ~1'x2' mosaic maps of the area around four HH objects from the same protostellar source (RNO43), at an angular resolution similar to ground-based observations (~1"). For this, we will exploit ALMA's capability to map regions at different frequencies, with similar synthesized beams. The HH knots (i.e., bright optical/NIR emission from shocks arising from the interaction of the protostellar wind and the ambient gas) we plan to observe lie at different distances from the source and are interacting with drastically different ambient density gas. Temperature estimates using molecular line ratio heavily depend on the optical depth of the line, and thus it is essential we obtain 13CO measurements to estimate the 12CO line opacity. 3. Number of sources Four 1'x2' fields surrounding different HH knots from one giant protostellar jet. 4. Coordinates: 4.1. RA~5:30 Dec~12:50 4.2. Moving target: NO 4.3. Time critical: NO 4.4. Scheduling constraints: NO 5. Spatial scales: 5.1. Angular resolution (arcsec): 1" (in order to compare with ground-based optical and NIR images, as well as Spitzer mid-IR images) 5.2. Range of spatial scales/FOV (arcsec): 60" x 120" 5.3. Required pointing accuracy: (arcsec) 0.6" (for accurate mosaic imaging at all bands) 6. Observational setup 6.1. Single dish total power data: required Observing modes for single dish total power: Position switch on-the-fly mapping (can't do freq. switch, as low-level high velocity spectral wings are expected) 6.2. Stand-alone ACA: No 6.3. Cross-correlation of 7m ACA and 12m baseline-ALMA antennas: beneficial 6.4. Subarrays of 12m baseline-ALMA antennas: NO 7. Frequencies: 7.1. Receiver band: Band 3, 6, 7, 8, AND 9 7.2. Lines and Frequencies (GHz): *Band 3: Observe 12CO(1-0) at 115.3 GHz and 13CO(1-0) at 110.2 GHz using two different spectral setups *Band 6: Simultaneous observations of 12CO(2-1) at 230.5 GHz and 13CO(2-1) at 220.4 GHz *Band 7: Simultaneous observations of 12CO(3-2) at 345.8 GHz and 13CO(3-2) at 330.6 GHz *Band 8: Observe 12CO(4-3) at 461.0 GHz and 13CO(4-3) at 440.8 GHz using two different spectral setups *Band 9: Observe 12CO(6-5) at 691.5 GHz and 13CO(6-5) at 661.5 GHz using two different spectral setups 7.3. Spectral resolution (km/s): 0.3 km/sec 7.4. Bandwidth or spectral coverage (km/s or GHz): 200 km/sec per line 8. Continuum flux density: NOT A CONTINUUM PROJECT 8.1. Typical value (Jy): (take average value of set of objects) (optional: provide range of fluxes for set of objects) 8.2. Required continuum rms (Jy or K): 8.3. Dynamic range within image: (from 7.1 and 7.2, but also indicate whether, e.g., weak objects next to bright objects) 8.4. Calibration requirements: absolute ( 1-3% / 5% / 10% / n/a ) repeatability ( 1-3% / 5% / 10% / n/a ) relative ( 1-3% / 5% / 10% / n/a ) 9. Line intensity: 9.1. Typical value (K or Jy): 0.6K to 10K 9.2. Required rms per channel (K or Jy): 0.2K 9.3. Spectral dynamic range: <20 9.4. Calibration requirements: absolute ( 1-3% / 5% / 10% / n/a ) 1-3% repeatability ( 1-3% / 5% / 10% / n/a ) 1-3% relative ( 1-3% / 5% / 10% / n/a ) 1-3% (Very good absolute calibration for all bands is needed in order to obtain accurate line ratios. We will need good repeatability because the mosaics will be done over several passes and some of the larger mosaics will be made by combining smaller mosaics.) 10. Polarization: NO 10.1. Required Stokes parameters: 10.2. Total polarized flux density (Jy): 10.3. Required polarization rms and/or dynamic range: 10.4. Polarization fidelity: 10.5. Required calibration accuracy: 11. Integration time for each observing mode/receiver setting (hr): Time estimated to obtain T_rms ~ 0.4 K per field. We plan to obtain Nyquist sampled mosaic, so T_rms ~0.2 K in final 1'x2' map. The following is for one 1'x2' mosaic (at the end we need to multiply by 4 to obtain total time for all planned fields) Band 3: We need a map at 115 GHz of 4x5 = 20 ptgs. time/ptg = 30min. total time = 10 hr Also, one map at 110GHz of 4X5 = 20 ptgs. time/ptg = 17min. total time = 5.7 hr Band 6: We need one map of 6x10 = 60 ptgs. time/ptg = 2min. total time = 2 hr Band 7: We need one map of 7x14 = 98 ptgs. time/ptg = 1min total time = 1.63 hr Band 8: We need one map at 461 GHz of 10x18 = 180 ptgs. time/ptg = 2.5min. total time = 7.5 hr Also, one map at 440.8 GHz of 10x18 = 180 ptgs. time/ptg. = 4 min. total time = 12 hr Band 9: We need one map at 691.5 GHz of 15x28 = 420 ptgs. time/ptg = 1.25min. total time = 8.75 hr Also, one map at 661.1 GHz of 15x28 = 420 ptgs. time/ptg. = 1 min. total time = 7 hr Total for one field at all frequencies = 10 + 5.7 + 2 + 1.63 + 7.5 + 12 + 8.75 + 7 ~ 54.6 ~ 55hr So, for all 4 regions, a total of 220hr. For ACA 7m array:We will need 4 times the integration of the 50 antenna ALMA array, to achieve same RMS. However, primary beam is 1.7 larger, so for mosaic we only need a factor of 1.4 more time with the ACA 7m array than the full ALMA array. That is, ~ 55 x 1.4 x 4 ~ 77 x 4 ~ 308hr ~310hr For total power: We will assume that we will get the ACA total power time at the same time as the ACA 7m data although in a separate sub-array. We will need to get a larger area than the synthesis maps to get out of the CO emission (so residual striping can be calibrated out in post-processing). The beam is smaller than the ACA 7m dishes and the mosaic region will be larger. It is not clear whether we will need the same integration time on source in total power as with the ACA. In this proposal, we assume we will not need as much time on source (it will be confusion limited?) so we assume the total integration time for the ACA (12m TP) to be the same as the ACA(7m array) = 310 hrs 12. Total integration time for program (hr): 220 (12m array) + 310 (ACA 7m array) + 310 (ACA TP) This does not include overhead for calibration and slew times (which will be significant for such large mosaics). 13. Comments on observing strategy : NONE -------------------------------------------------- Review v2.0: 2.2.12 - 2.2.15 I found no problems with these proposals other than the standard question of calculating ACA time.