SIMBAD references

2018MNRAS.478.1017O - Mon. Not. R. Astron. Soc., 478, 1017-1041 (2018/July-3)

Layers in the Central Orion nebula.

O'DELL C.R.

Abstract (from CDS):

The existence of multiple layers in the inner Orion nebula has been revealed using data from an Atlas of spectra at 2 arcsec and 12 km s–1 resolution. These data were sometimes grouped over Samples of 10 arcsecx10 arcsecto produce high signal-to-noise spectra and sometimes grouped into sequences of pseudo-slit Spectra of 12′′.8-39 arcsec width for high spatial resolution studies. Multiple velocity systems were found: VMIF traces the Main Ionization Front (MIF), Vscat arises from back-scattering of VMIF emission by particles in the background Photon Dissociation Region (PDR), Vlow is an ionized layer in front of the MIF and if it is the source of the stellar absorption lines seen in the Trapezium stars, it must lie between the foreground Veil and those stars, Vnew,[OIII] may represent ionized gas evaporating from the Veil away from the observer. There are features such as the Bright Bar where variations of velocities are due to changing tilts of the MIF, but velocity changes above about 25 arcsec arise from variations in velocity of the background PDR. In a region 25 arcsec ENE of the Orion-S Cloud one finds dramatic changes in the [OIII] components, including the signals from the Vlow,[OIII] and VMIF,[OIII] becoming equal, indicating shadowing of gas from stellar photons of >24.6 eV. This feature is also seen in areas to the west and south of the Orion-S Cloud.

Abstract Copyright: © 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society

Journal keyword(s): atomic processes - radiation mechanisms: general - ISM: atoms - dust, extinction - Hii regions - ISM: individual objects: Orion nebula (NGC 1976)

Simbad objects: 21

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2018MNRAS.478.1017O and select 'bookmark this link' or equivalent in the popup menu


2019.12.06-00:02:52

© Université de Strasbourg/CNRS

    • Contact