The Calibration of Star Formation Rate Indicators for WISE 22 Micron
  Selected Galaxies in the SDSS
  We study star formation rate (SFR) indicators for Wide-field Infrared Survey
Explorer (WISE) 22 \mu m selected, star-forming galaxies at 0.01 < z < 0.3 in
the Sloan Digital Sky Survey. Using extinction-corrected H\alpha\ luminosities
and total infrared luminosities as reference SFR estimates, we calibrate WISE
mid-infrared (MIR) related SFR indicators. Both 12 and 22 \mu m monochromatic
luminosities correlate well with the reference SFR estimates, but tend to
underestimate SFRs of metal-poor galaxies (at lower than solar metallicity),
consistent with previous studies. We mitigate this metallicity dependence using
a linear combination of observed H\alpha\ and WISE MIR luminosities for SFR
estimates. The combination provides robust SFR measurements as Kennicutt et al.
(2009) applied to Spitzer data. However, we find that the coefficient a in
L_H\alpha(obs) + a L_MIR increases with SFR, and show that a non-linear
combination of observed H\alpha\ and MIR luminosities gives the best SFR
estimates with small scatters and with little dependence on physical
parameters. Such a combination of H\alpha\ and MIR luminosities for SFR
estimates is first applied to WISE data. We provide several SFR recipes using
WISE data applicable to galaxies with 0.1 <~ SFR (M_sun yr^-1) <~ 100.
