An analysis of infrared emission spectra from the regions near the Galactic Center

Marcella Contini

School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel

Paper: MNRAS, July 2009, in press

EPrint Server: 0907.2014


Abstract:

We present consistent modelling of line and continuum IR spectra in the region close to the Galactic center. The models account for the coupled effect of shocks and photoionization from an external source. The results show that the shock velocities range between 65 and 80 km/sec , the pre-shock densities between 1\cm3 in the ISM to 200\cm3 in the filamentary structures. The pre-shock magnetic field increases from 5. 10-6 gauss in the surrounding ISM to 8 10-5 gauss in the Arched Filaments. The stellar temperatures are 38000 K in the Quintuplet cluster and 27000 K in the Arches Cluster. The ionization parameter is relatively low (< 0.01 ) with the highest values near the clusters, reaching a maximum >0.01 near the Arches Cluster. Depletion from the gaseous phase of Si is found throughout the whole observed region, indicating the presence of silicate dust. Grains including iron, are concentrated throughout the Arched Filaments. The modelling of the continuum SED in the IR range, indicates that a component of dust at temperatures of 100-200 K is present in the central region of the Galaxy. Radio emission appears to be thermal bremsstrahlung in the E2-W1 filaments crossing strip, however a synchrotron component is not excluded. More data are necessary to resolve this questions.


Preprints available from the authors at marcel@wise.tau.ac.il , or the raw TeX (no figures) if you click here.

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