Linking ice and gas in the Lambda Orionis Barnard 35A cloud
  Dust grains play an important role in the synthesis of molecules in the
interstellar medium, from the simplest species to complex organic molecules.
How some of these solid-state molecules are converted into gas-phase species is
still a matter of debate. Our aim is to directly compare ice and gas abundances
of methanol (CH$_3$OH) and CO, and to investigate the relationship between ice
and gas in low-mass protostellar envelopes. We present Submillimeter Array and
Atacama Pathfinder EXperiment observations of gas-phase CH$_3$OH and CO towards
the multiple protostellar system IRAS05417+0907 located in the B35A cloud. We
use archival AKARI ice data toward the same target to calculate CH$_3$OH and CO
gas-to-ice ratios. The CO isotopologues emissions are extended, whereas the
CH$_3$OH emission is compact and traces the giant outflow emanating from
IRAS05417+0907. A discrepancy between submillimeter dust emission and H$_2$O
ice column density is found for B35A$-$4 and B35A$-$5, similar to what has
previously been reported. B35A$-$2 and B35A$-$3 are located where the
submillimeter dust emission peaks and show H$_2$O column densities lower than
for B35A$-$4. The difference between the submillimeter continuum emission and
the infrared H$_2$O ice observations suggests that the distributions of dust
and H$_2$O ice differ around the young stellar objects in this dense cloud. The
reason for this may be that the sources are located in different environments
resolved by the interferometric observations: B35A$-$2, B35A$-$3 and in
particular B35A$-$5 are situated in a shocked region plausibly affected by
sputtering and heating impacting the submillimeter dust emission pattern, while
B35A$-$4 is situated in a more quiescent part of the cloud. Gas and ice maps
are essential to connect small-scale variations in the ice composition with
large-scale astrophysical phenomena probed by gas observations.
