Mid-IR Luminosities and UV/Optical Star Formation Rates at z<1.4

Details Mid-IR Luminosities and UV/Optical Star Formation Rates at z<1.4 Mid-IR Luminosities and UV/Optical Star Formation Rates at z<1.4

Jan 2009

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009aas...21336202s&link_type=abstract

American Astronomical Society, AAS Meeting #213, #362.02; Bulletin of the American Astronomical Society, Vol. 41, p.512

Other

Scientific paper

Ultraviolet continuum and mid-IR emission constitute the basis of two widely used star formation indicators. We study 5500 optically-selected galaxies in the Extended Groth Strip, with spectroscopic redshifts below 1.4. We use dust-reddened stellar population models and Bayesian SED fitting to obtain dust-corrected SFRs from deep UV, optical and near-IR photometry taken from the AEGIS dataset. These UV/optical SFRs are calculated over several timescales (from 0.1 to several Gyr), and are compared to infrared luminosities extrapolated from very deep MIPS 24 um observations from FIDEL survey. We find that for the blue, actively star forming galaxies the correlation between the IR luminosity and the UV/optical SFR strengthens when SFR is averaged over progressively longer timescales, with the best correlation (least scatter) being with SFRs averaged over 1-3 Gyr. Alternatively, we show that IR luminosity correlates better with dust-corrected B-band luminosity than with dust-corrected UV light. This is true for all redshift bins in 0.2 < z < 1.4 range, and argues for a greater role of older populations in mid-IR heating than usually assumed. LIRGs and normal star forming galaxies in our sample are mostly optically thin, with far-UV attenuation not exceeding 4 magnitudes. Among the green valley and red sequence galaxies we find many that seemingly exhibit an IR excess (with respect to the dust-corrected UV SFR). However, in most cases this excess can be accounted for by dust heating from evolved populations, i.e., the "excess” arises from incorrectly attributing the IR light to current star formation. We compare mid-IR luminosities of spectroscopically selected AGNs and otherwise similar galaxies without AGNs, but find no significant difference, arguing against the significant contribution of AGN to the mid-IR emission in our sample. We conclude that caution is required when interpreting the mid-IR light as star formation.

Affiliated with

Also associated with

No associations

Rating

Mid-IR Luminosities and UV/Optical Star Formation Rates at z<1.4 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Mid-IR Luminosities and UV/Optical Star Formation Rates at z<1.4, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mid-IR Luminosities and UV/Optical Star Formation Rates at z<1.4 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1700983