%0 Generic %1 tamura2013obscured %A Tamura, Yoichi %A Matsuda, Yuichi %A Ikarashi, Soh %A Scott, Kimberly S. %A Hatsukade, Bunyo %A Umehata, Hideki %A Saito, Tomoki %A Nakanishi, Kouichiro %A Yun, Min S. %A Ezawa, Hajime %A Hughes, David H. %A Iono, Daisuke %A Kawabe, Ryohei %A Kohno, Kotaro %A Wilson, Grant W. %D 2013 %K blobs lyalpha sfr %T Obscured star formation in Ly-alpha blobs at z = 3.1 %U http://arxiv.org/abs/1301.2596 %X We present results from the AzTEC/ASTE 1.1-mm imaging survey of 35 Ly-alpha blobs (LABs) found in the SSA22 protocluster at z = 3.1. These 1.1-mm data reach an r.m.s. noise level of 0.7-1 mJy/beam, making this the largest millimetre-wave survey of LABs to date. No significant (> 3.5-sigma) emission is found in any of individual 35 LABs, and from this, we estimate 3-sigma upper limits on the far-infrared luminosity of L_FIR < 2e+12 Lsun. Stacking analysis reveals that the 1.1-mm flux density averaged over the LABs is S(1.1mm) < 0.40 mJy (3-sigma), which places a constraint of L_FIR < 4.5e+11 Lsun. This indicates that earlier 850-um measurements of the LABs may have overestimated their flux densities. Our results suggest that LABs on average have little ultra-luminous 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 ~ 10^3 Msun/yr. Observations with ALMA are needed to directly study the obscured part of star-formation activity in the LABs.

@misc{tamura2013obscured, abstract = {We present results from the AzTEC/ASTE 1.1-mm imaging survey of 35 Ly-alpha blobs (LABs) found in the SSA22 protocluster at z = 3.1. These 1.1-mm data reach an r.m.s. noise level of 0.7-1 mJy/beam, making this the largest millimetre-wave survey of LABs to date. No significant (> 3.5-sigma) emission is found in any of individual 35 LABs, and from this, we estimate 3-sigma upper limits on the far-infrared luminosity of L_FIR < 2e+12 Lsun. Stacking analysis reveals that the 1.1-mm flux density averaged over the LABs is S(1.1mm) < 0.40 mJy (3-sigma), which places a constraint of L_FIR < 4.5e+11 Lsun. This indicates that earlier 850-um measurements of the LABs may have overestimated their flux densities. Our results suggest that LABs on average have little ultra-luminous 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 ~ 10^3 Msun/yr. Observations with ALMA are needed to directly study the obscured part of star-formation activity in the LABs.}, added-at = {2013-01-15T16:44:16.000+0100}, author = {Tamura, Yoichi and Matsuda, Yuichi and Ikarashi, Soh and Scott, Kimberly S. and Hatsukade, Bunyo and Umehata, Hideki and Saito, Tomoki and Nakanishi, Kouichiro and Yun, Min S. and Ezawa, Hajime and Hughes, David H. and Iono, Daisuke and Kawabe, Ryohei and Kohno, Kotaro and Wilson, Grant W.}, biburl = {https://www.bibsonomy.org/bibtex/2ebea80eda53a5dbfd5a7f56bfeb42eab/miki}, description = {[1301.2596] Obscured star formation in Ly-alpha blobs at z = 3.1}, interhash = {61799b20c06ca3310884d59ef43b7f03}, intrahash = {ebea80eda53a5dbfd5a7f56bfeb42eab}, keywords = {blobs lyalpha sfr}, note = {cite arxiv:1301.2596Comment: 7 pages, 4 figures, 1 table, accepted for publication in MNRAS}, timestamp = {2013-01-15T16:44:16.000+0100}, title = {Obscured star formation in Ly-alpha blobs at z = 3.1}, url = {http://arxiv.org/abs/1301.2596}, year = 2013 }