MID-INFRARED POLYCYCLIC AROMATIC HYDROCARBON AND H2 EMISSION AS A PROBE OF PHYSICAL CONDITIONS IN EXTREME PHOTODISSOCIATION REGIONS Export

@article{citeulike:6082823, abstract = {Mid-infrared (mid-IR) observations of polycyclic aromatic hydrocarbons (PAHs) and molecular hydrogen emission are a potentially powerful tool to derive physical properties of dense environments irradiated by intense UV fields. We present new, spatially resolved, Spitzer mid-IR spectroscopy of the high UV field and dense photodissociation region (PDR) around Monoceros R2, the closest ultracompact H ii region, revealing the spatial structure of ionized gas, PAHs, and H2 emissions. Using a PDR model and PAH emission feature fitting algorithm, we build a comprehensive picture of the physical conditions prevailing in the region. We show that the combination of the measurement of PAH ionization fraction and of the ratio between the H2 0-0 S(3) and S(2) line intensities, respectively, at 9.7 and 12.3 μm, allows us to derive the fundamental parameters driving the PDR: temperature, density, and UV radiation field when they fall in the ranges T = 250-1500 K, nH = 10^4-10^6 cm–3, and G0 = 10^3-10^5, respectively. These mid-IR spectral tracers thus provide a tool to probe the similar but unresolved UV-illuminated surface of protoplanetary disks or the nuclei of starburst galaxies.}, author = {Bern\'{e}1, O. and Fuente, A. and Goicoechea, J. R. and Pilleri, P. and Gonz\'{a}lez-Garc\'{\i}a, M. and Joblin, C.}, citeulike-article-id = {6082823}, citeulike-linkout-0 = {http://www.iop.org/EJ/article/-alert=42660/1538-4357/706/1/L160/apjl_706_1_160.html}, journal = {he Astrophysical Journal}, keywords = {pdrs}, pages = {L160+}, posted-at = {2009-11-07 12:23:13}, priority = {2}, title = {MID-INFRARED POLYCYCLIC AROMATIC HYDROCARBON AND H2 EMISSION AS A PROBE OF PHYSICAL CONDITIONS IN EXTREME PHOTODISSOCIATION REGIONS}, url = {http://www.iop.org/EJ/article/-alert=42660/1538-4357/706/1/L160/apjl_706_1_160.html}, volume = {706}, year = {2009} }

TY - JOUR ID - citeulike:6082823 L3 - citeulike-article-id:6082823 N2 - Mid-infrared (mid-IR) observations of polycyclic aromatic hydrocarbons (PAHs) and molecular hydrogen emission are a potentially powerful tool to derive physical properties of dense environments irradiated by intense UV fields. We present new, spatially resolved, Spitzer mid-IR spectroscopy of the high UV field and dense photodissociation region (PDR) around Monoceros R2, the closest ultracompact H ii region, revealing the spatial structure of ionized gas, PAHs, and H2 emissions. Using a PDR model and PAH emission feature fitting algorithm, we build a comprehensive picture of the physical conditions prevailing in the region. We show that the combination of the measurement of PAH ionization fraction and of the ratio between the H2 0-0 S(3) and S(2) line intensities, respectively, at 9.7 and 12.3 μm, allows us to derive the fundamental parameters driving the PDR: temperature, density, and UV radiation field when they fall in the ranges T = 250-1500 K, nH = 10^4-10^6 cm–3, and G0 = 10^3-10^5, respectively. These mid-IR spectral tracers thus provide a tool to probe the similar but unresolved UV-illuminated surface of protoplanetary disks or the nuclei of starburst galaxies. JF - he Astrophysical Journal TI - MID-INFRARED POLYCYCLIC AROMATIC HYDROCARBON AND H2 EMISSION AS A PROBE OF PHYSICAL CONDITIONS IN EXTREME PHOTODISSOCIATION REGIONS VL - 706 SP - L160 KW - pdrs AU - Berné1, O AU - Fuente, A AU - Goicoechea, JR AU - Pilleri, P AU - González-García, M AU - Joblin, C PY - 2009/// UR - http://www.iop.org/EJ/article/-alert=42660/1538-4357/706/1/L160/apjl_706_1_160.html ER -