Title   mm VLBI observations of core-jets
Pi     C. Carilli
Time   50 hrs

1.6.4: Name -- mm VLBI observations of core-jets
    Authors: C. Carilli

2. Science goal: We propose VLBI imaging using the Pacific array (see
1.6.3) at 220 GHz of a representative sample of radio jets in low
redshift radio galaxies. These data will probe to scales of 20uas,
corresponding to 50 Schwarzschild radii at the distance of M87 (17
Mpc). Observations of M87 suggest that these scales correspond to the
fundamental regime where initial jet collimation occurs (Junor et
al. 1999 Nature 401, 891). Hence these observations will provide a key
test of jet formation models in radio galaxies.

3. Number of sources: 10

4. Coordinates:

  4.1. Choose equatorial sources: Declination = 0 +/- 10deg

  4.2. Moving target: no

  4.3. Time critical: no

5.  Spatial scales:

  5.1. Angular resolution: 20uas

  5.2. Range of spatial scales/FOV: 20 uas -- 200 uas

  5.3. Single dish: no

  5.4. ACA: no

  5.5. Subarrays: no

6. Frequencies:

  6.1. Receiver band: Band 6 -- 220 GHz  in Configuration D or E,
       phased-array

  6.2. Lines and Frequencies

  6.3. Spectral Resolution (km/s)

  6.4. Bandwidth or spectral coverage: 1 GHz x 2pol (set by VLBI
recorder)

7. Continuum flux density:

  7.1. Typical value:

  7.2. Continuum peak value: typically of order 1 Jy

  7.3. Required continuum rms:
        ALMA - HHT baseline, 10 min rms = 0.7 mJy
        ALMA - LMT baseline, 10 min rms = 0.2 mJy

  7.4. Dynamic range in image: 1e3

8. Line intensity:

  8.1. Typical value:

  8.2. Required rms per channel:

  8.3. Spectral dynamic range:

9. Polarization: yes

10. Integration time per setting:
  10 sources at 5 hrs per source

11. Total integration time for program: 50 hr

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

Review Jean Turner: mm-VLBI can probe to 50 Rsch at M87, an important
region for probing jet physics. Proposed sample is 10 sources, 50
hours, this is reasonable although getting 50 hrs to do VLBI is often
tricky, but this is an obvious project & obvious sources (like M87).

I have to take Chris's numbers on faith since they involve
other telescopes and VLBI.

--------------------------------------------------
Review v2.0:
 
1.6.4 mm VLBI observations of core-jets (Carilli)

Not revised since DRSP 1.1. Nothing needs to be added to the review
back then, no severe impact through reduction to 50 antennas, no need
for ACA.