The collapse and expansion regimes of photoevaporated clumps
Por:
Raga, A. C., Canto, J., Estrella-Trujillo, D., Velazquez, P. F.
Publicada:
1 oct 2020
Resumen:
We present a model for dense clumps in photoionized regions in the
`cometary plasmon' regime. We consider that as these plasmons accelerate
outwards from the external ionizing photon source (as a result of the
back-reaction of the photoevaporated wind from the clumps), they move
into regions of decreasing external ionizing photon fluxes (resulting
from the geometrical dilution of the ionizing radiation, and possibly
also from absorption due to intervening material). We find the presence
of two regimes: a `vanishing plasmon' regime, in which the clump rapidly
accelerates, compresses, and becomes fully photoionized without
travelling far from the photon source, and an `expanding plasmon'
regime, in which the clump travels over a considerable radial domain,
and expands as a result of the lower impinging ionizing photon fluxes
(before eventually decreasing in size and becoming fully photoionized).
Interestingly, the cometary clumps of the Helix nebula are at the
boundary between these two regimes, and therefore correspond to clumps
that travel over a relatively extended radial domain while keeping an
approximately constant size.
Filiaciones:
Raga, A. C.:
Univ Nacl Autonoma Mexico, Inst Ciencias Nucl, AP 70-543, Mexico City 04510, DF, Mexico
Canto, J.:
Univ Nacl Autonoma Mexico, Inst Astron, Ap 70-468, Mexico City 04510, DF, Mexico
Estrella-Trujillo, D.:
Univ Nacl Autonoma Mexico, Inst Ciencias Nucl, AP 70-543, Mexico City 04510, DF, Mexico
Velazquez, P. F.:
Univ Nacl Autonoma Mexico, Inst Ciencias Nucl, AP 70-543, Mexico City 04510, DF, Mexico
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