Abstract
We study the heating mechansims and Ly\alpha escape fractions of 35
Ly\alpha blobs (LABs) at z = 3.1 in the SSA22 field, using the submillimeter
(submm) data from the ALMA and the SCUBA-2 on the JCMT, and the radio data from
the VLA. With ALMA and JCMT/SCUBA-2, we have identified dust continuum sources
in 11 out of 35 LABs in the SSA22 field, with star formation rates (SFRs) of
above 100Msun/yr. Using VLA, we have detected likely radio counterparts in 9
out of 29 LABs in the SSA22 field. We find that a radio excess in the
submm/radio detected LABs is common, suggesting that active galactic nuclei
(AGN) may often be present in these systems. Most radio sources without X-ray
counterparts are located in the centers of the LABs. However, it is surprising
that all X-ray counterparts avoid the central regions of their LABs. Possibly
these X-ray sources are associated with merging systems, which re-distribute
the interstellar meidium (ISM) and circumgalactic medium (CGM), leading to
highly inhomogeneous gas. Alternatively, AGN and its feedback may also be
responsible for inhomogeneous Ly\alpha morphology in these LABs. We obtain
escape fractions of Ly\alpha photons for the LABs based on the submm and
Ly\alpha data, and find that the Ly\alpha escape fractions in the LABs are
significantly lower than those found for Ly\alpha emitters (LAEs) in other
studies. We suspect that this large difference is due to the SCUBA-2 detection
threshold, the high dust attenuation indicated by the large SFRs in our sample,
as well as the dense large-scale environment in SSA22.
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