Multi-wavelength properties of Spitzer-selected starbursts at z~2
  A complete sample of 33 sources believed to be starbursts
("5.8micron-peakers") was selected in the (0.5 sq. deg.) J1046+56 field with
selection criteria F_(24micron)>400muJy, the presence of a redshifted stellar
emission peak at 5.8um, and r'(Vega)>23. The field, part of the SWIRE Lockman
Hole field, benefits from very deep VLA/GMRT 20cm, 50cm, and 90cm radio data
(all 33 sources are detected at 50cm), and deep 160micron and 70micron Spitzer
data. The 33 sources, with photometric redshifts ~1.5-2.5, were observed at
1.2mm with IRAM-30m/MAMBO to an rms ~0.7-0.8mJy in most cases. Their
millimeter, radio, 7-band Spitzer, and near-IR properties were jointly
analyzed. The entire sample of 33 sources has an average 1.2mm flux density of
1.56+/-0.22mJy and a median of 1.61mJy, so the majority of the sources can be
considered SMGs. Four sources have confirmed 4sigma detections, and nine were
tentatively detected at the 3sigma level. Because of its 24micron selection,
our sample shows systematically lower F_(1.2mm)/F_(24micron) flux ratios than
classical SMGs, probably because of enhanced PAH emission. A median FIR SED was
built by stacking images at the positions of 21 sources in the region of
deepest Spitzer coverage. Its parameters are T_(dust)=37+/-8K,
L_(FIR)=2.5x10^{12}Lo, and SFR=450Mo/yr. The FIR-radio correlation provides
another estimate of L_(FIR) for each source, with an average value of
4.1x10^{12}Lo; however, this value may be overestimated because of some AGN
contribution. Most of our targets are also luminous star-forming BzK galaxies
which constitute a significant fraction of weak SMGs at 1.7<z<2.3.
