The nature of GRB-selected submillimeter galaxies:: Hot and young

We present detailed fits of the spectral energy distributions (SEDs) of four submillimeter galaxies selected by the presence of a gamma-ray burst (GRB) event (GRBs 980703, 000210, 000418, and 010222). These faint similar to 3 mJy submillimeter emitters at redshift similar to 1 are characterized by an unusual combination of long- and short-wavelength properties, namely enhanced submillimeter and/or radio emission combined with optical faintness and blue colors. We exclude an active galactic nucleus as the source of long- wavelength emission. From the SED fits, we conclude that the four galaxies are young (ages < 2 Gyr), highly star forming (star formation rates similar to 150 M-Theta yr(-1)), low mass (stellar masses similar to 10(10) M-Theta), and dusty (dust masses similar to 3 x 10(8) M-Theta). Their high dust temperatures (T-d greater than or similar to 45 K) indicate that GRB host galaxies are hotter, younger, and less massive counterparts to the submillimeter-selected galaxies detected so far. Future facilities like Herschel, the James Clerk Maxwell Telescope SCUBA-2, and ALMA will test this hypothesis, enabling measurement of dust temperatures of fainter GRB-selected galaxies.