Please use this identifier to cite or link to this item:
Obscured star formation in Lyα blobs at z = 3.1
David Hughes
Acceso Abierto
Galaxies: evolution
Galaxies: formation
Galaxies: high-redshift
Galaxies: starburst
We present results from the AzTEC/ASTE 1.1-mm imaging survey of 35 Lyα blobs (LABs) found in the SSA22 protocluster at z = 3.1. These 1.1-mm data reach an rms noise level of 0.7–1 mJy beam⁻¹, making this the largest millimetre-wave survey of LABs to date. While one (or possibly two) out of 35 LABs might be detected at 3σ level, no significant (≥3.5σ) emission is found in any of individual 35 LABs. From this, we estimate 3σ upper limits on the far-infrared luminosity of LFIR < 2 × 10¹² L๏ (the dust temperature of 35K and the emissivity index of 1.5 are assumed). Stacking analysis reveals that the 1.1-mm flux density averaged over the LABs is S₁.₁mm < 0.40 mJy (3σ), which places a constraint of LFIR< 4.5 × 10¹¹ L๏. These data constrain the dust spectral energy distributions of the LABs more tightly than ever if their spectral indices at rest-frame wavelength of ≈ 240 μm are similar to those found in (ultra-)luminous infrared galaxies at 0.2 < z < 0.3. Our results suggest that LABs on average have little ultraluminous obscured star formation, in contrast to a long-believed picture that LABs undergo an intense episode of dusty star formation activities with star formation rates of ∼10³M๏ yr⁻¹. Observations with the Atacama Large Millimeter/submillimeter Array are needed to directly study the obscured part of star formation activity in the LABs.
Monthly Notices of the Royal Astronomical Society
Público en general
Tamura, Y., et al., (2013), Obscured star formation in Lyα blobs at z = 3.1, Monthly Notices of the Royal Astronomical Society, Vol. 430(4):2768-2773
Versión aceptada
acceptedVersion - Versión aceptada
Appears in Collections:Artículos de Astrofísica

Upload archives