It is thought that a class of broad absorption line (BAL) QSOs,
characterized by Fe absorption features in their UV spectra (called
`FeLoBALs'), could mark a transition stage between the end of an
obscured starburst event and a youthful QSO beginning to shed its dust
cocoon, where Fe has been injected into the interstellar medium by the
starburst. To test this hypothesis, we have undertaken deep
Submillimetre Common-User Bolometer Array 2 (SCUBA-2) 850 μm
observations of a sample of 17 FeLoBAL QSOs with 0.89 ≤ z ≤ 2.78
and -23.31 ≤ MB ≤ -28.50 to directly detect an excess
in the thermal emission of the dust which would probe enhanced star
formation activity. We find that FeLoBALs are not luminous sources in
the sub-mm, none of them are individually detected at 850 μm, nor as
a population through stacking (Fs = 1.14 ± 0.58 mJy).
Statistical and survival analyses reveal that FeLoBALs have sub-mm
properties consistent with BAL and non-BAL QSOs with matched redshifts
and magnitudes. An Spectral Energy Distribution fitting analysis shows
that the far-infrared emission is dominated by active galactic nuclei
activity, and a starburst component is required only in 6/17 sources of
our sample; moreover the integrated total luminosity of 16/17 sources is
L ≥ 1012 L⊙, high enough to classify
FeLoBALs as infrared luminous. In conclusion, we do not find any
evidence in support of FeLoBAL QSOs being a transition population
between an ultraluminous infrared galaxy (ULIRG) and an unobscured QSO;
in particular, FeLoBALs are not characterized by a cold starburst which
would support this hypothesis.