[C II] 158 μm luminosities and star formation rate in dusty starbursts and active galactic nuclei

Sargsyan, L.; Lebouteiller, V.; Weedman, D.; Spoon, H.; Bernard-Salas, J.; Engels, D.; Stacey, G.; Houck, J.; Barry, D.; Miles, J. and Samsonyan, A. (2012). [C II] 158 μm luminosities and star formation rate in dusty starbursts and active galactic nuclei. Astrophysical Journal, 755(2), article no. 171.

DOI: https://doi.org/10.1088/0004-637X/755/2/171

Abstract

Results are presented for [C II] 158μm line fluxes observed with the Herschel PACS instrument in 112 sources with both starburst and active galactic nucleus (AGN) classifications, of which 102 sources have confident detections. Results are compared with mid-infrared spectra from the Spitzer Infrared Spectrometer and with L_ir from IRAS fluxes; AGN/starburst classifications are determined from equivalent width of the 6.2μm polycyclic aromatic hydrocarbon (PAH) feature. It is found that the [C II] line flux correlates closely with the flux of the 11.3μm PAH feature independent of AGN/starburst classification, log [f([C II] 158μm)/f(11.3μm PAH)] = −0.22 ± 0.25. It is concluded that the [C II] line flux measures the photodissociation region associated with starbursts in the same fashion as the PAH feature. A calibration of star formation rate (SFR) for the starburst component in any source having [C II] is derived comparing [C II] luminosity L([C II]) to L_ir with the result that log SFR = log L([C II)]) − 7.08±0.3, for SFR in M_⊙ yr−1 and L([C II]) in L_⊙. The decreasing ratio of L([C II]) to L_ir in more luminous sources (the “[C II] deficit”) is shown to be a consequence of the dominant contribution to Lir arising from a luminous AGN component because the sources with the largest L_ir and smallest L([C II])/L_ir are AGNs.

Viewing alternatives

Metrics

Item Actions

Export

You can export this page using these formats Digital Object Identifier - DOI