Title  Chemical Enhancements in Outflows
Pi     R. Plume
Time   16 hrs
1. Name: Chemical Enhancements in Outflows
     Authors: R. Plume, ...

2.  Science Goal: To determine the location and mechanism by which the
enhancement of HCO+ occurs in molecular outflows.  Rawlings et
al. (2000, MNRAS, 313, 461) have suggested that the HCO+ enhancement
occurs continuously along the outflow in a turbulent mixing layer.
This model is supported by OVRO observations of HCO+ 1-0 in L1527 by
Hogerheijde et al. (1998, ApJ, 502, 315) which shows an "X-shaped"
distribution of HCO+ emission.  However, the OVRO resolution was too
poor to confirm this model prediction in the other sources observed by
Hogerheijde et al.  Given the compact nature of these sources, it is
also possible that the HCO+ enhancement occurs at the base of the jet
and then gets carried downstream.  We would like to examine the HCO+
3-2 emission from L1527, to better resolve
  the X-shaped structure first seen by Hogerheijde et al in HCO+ 1-0, as 
well as from L1489, L1551, and
L1535 to determine the location of the HCO+ emission.  Previous 
single-dish observations show that the
HCO+ 3-2 lines are a few K in strength and a few km/s wide.  This 
project should also be extended to
outflows from high-mass protostellar objects (e.g. G5.89) in order to 
determine if there are quantitative
differences between the HCO+ enhancement mechanisms in high and low 
mass YSOs.

3. Number of sources: 8

4.  Coordinates:

	4.1.  L1527, L1489, L1551, L1535 (RA ~ 04h 30m, DEC ~ 18-23 degrees)
	       G5.89-0.39 (aka W28A2) (RA ~ 17h 57m, DEC ~ -24 degrees)
	       3 other high-mass outflows (RA = any, DEC = any)

	4.2. Moving Target: no

	4.3. Time critical: no

5. Spatial Scales:
	
	5.1. Angular Resolution: 0.5"

	5.2. Range of Spatial Scales/FOV: 20"

	5.3. Single Dish: yes

	5.4. ACA: yes

	5.5. subarrays: no

6. Frequencies

	6.1. receiver band: 6

	6.2. Line: HCO+ 3-2
	        Frequency: 267 GHz

	6.3. Spectral resolution: 0.2 km/s

	6.4. Spectral Coverage: 60 km/s

7. Continuum Flux Density:

	7.1. Typical value:

	7.2. Continuum peak value:

	7.3. Required continuum rms:

	7.4. Dynamic Range in image:

8. Line Intensity:
	
	8.1. Typical value: 2-8 K

	8.2. Required rms per channel: 0.2 K

	8.3. Spectral Dynamic Range: 10

9. Polarization: no

10. Integration time per setting:  2 hours x 8 sources

11. Total Integration time for program: 16 hrs

***********************************************************************

Review Lee Mundy: OK.--------------------------------------------------
Review v2.0:
 
ok