Chemical abundances in the protoplanetary disk LV2 (Orion) - II: High
  dispersion VLT observations and microjet properties
  Integral field spectroscopy of the LV2 proplyd is presented taken with the
VLT/FLAMES Argus array at an angular resolution of 0.31x0.31 arcsec^2 and
velocity resolutions down to 2 km/s per pixel. Following subtraction of the
local M42 emission, the spectrum of LV2 is isolated from the surrounding
nebula. We measured the heliocentric velocities and widths of a number of lines
detected in the intrinsic spectrum of the proplyd, as well as in the adjacent
Orion nebula within a 6.6 x 4.2 arcsec^2 FoV. It is found that far-UV to
optical collisional lines with critical densities, Ncrit, ranging from 10^3 to
10^9 /cm^3 suffer collisional de-excitation near the rest velocity of the
proplyd correlating tightly with their critical densities. Lines of low Ncrit
are suppressed the most. The bipolar jet arising from LV2 is spectrally and
spatially well-detected in several emission lines. We compute the [O III]
electron temperature profile across LV2 in velocity space and measure steep
temperature variations associated with the red-shifted lobe of the jet,
possibly being due to a shock discontinuity. From the velocity-resolved
analysis the ionized gas near the rest frame of LV2 has Te = 9200 +/- 800 K and
Ne ~ 10^6 /cm^3, while the red-shifted jet lobe has Te ~ 9000 - 10^4 K and Ne ~
10^6 - 10^7 /cm^3. The jet flow is highly ionized but contains dense
semi-neutral clumps emitting neutral oxygen lines. The abundances of N+, O++,
Ne++, Fe++, S+, and S++ are measured for the strong red-shifted jet lobe. Iron
in the core of LV2 is depleted by 2.54 dex with respect to solar as a result of
sedimentation on dust, whereas the efficient destruction of dust grains in the
fast microjet raises its Fe abundance to at least 30 per cent solar. Sulphur
does not show evidence of significant depletion on dust, but its abundance both
in the core and the jet is only about half solar.
