large scale co emission in the orion nebula núria marcelino (nrao-cv) olivier berné (leiden obs,...

Large Scale CO Emission in the Orion Nebula

Núria Marcelino (NRAO-CV)

Olivier Berné (Leiden Obs, The Netherlands)

José Cernicharo (CSIC/INTA, Spain)

HST CO (2-1)

Motivations The closest (brightest) massive star forming region Prototypical source: observed at almost all

wavelengths Star formation features: hot cores, HII regions,

protostars, circumstellar disks, outflows, HH objects,

PDRs, etc. 12CO and 13CO: spatial distribution, kinematics, and

column densities of molecular gas Previous large scale CO maps have poor spectral

and/or angular resolution

Postdoc Symposium, April 11 2011

Observations IRAM 30M radiotelescope (Granada, Spain)

Size 1ox0.8o (63 submaps), centered at IRc2/KL :

=05h35m14.5s, =-05o22’29.3’’

HERA 3x3 multibeam receiver

12CO (2-1) @ 230.5 GHz

13CO (2-1) @ 220.4 GHz

Angular resolution ~ 11’’

(0.02 pc @ 414 pc)

Velocity resolution ~ 0.4 km/s



12CO (2-1)


13CO (2-1)


12CO (2-1)

12CO emission @ -5 to 8 km/s



IRAC 3.6 m


Orion Waves

Berné, Marcelino & Cernicharo (Nature, 466, 947)

Expansion of the HII region

provoked Kelvin-Helmholtz

instabilities and cloud

fragmentation

Intense and ionizing stellar irradiation

caused the acceleration of the clumps

First observational evidence of KH instabilities,

result of hydrodynamical feedback of massive stars

on their parental cloud


12CO emission @ 8 to 12 km/s




SCUBA 850 m

Conclusions Very complex dynamics and velocity structure

Clumps, filaments, cavities, pillars/cometary

globules, outflows, etc.

Interaction between massive star winds, HII

regions, and molecular ambient cloud: energy

transport, turbulence, formation of filaments,

triggered star formation, etc.

High angular and spectral resolutions are

essential to study in detail these processes


12CO (2-1) emission


large scale co emission in the orion nebula núria marcelino (nrao-cv) olivier berné (leiden obs,...

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