Towards DIB mapping in galaxies beyond 100 Mpc. A radial profile of the
  $\lambda$5780.5 diffuse interstellar band in AM 1353-272 B
  Diffuse Interstellar Bands (DIBs) are non-stellar weak absorption features of
unknown origin found in the spectra of stars viewed through one or several
clouds of Interstellar Medium (ISM). Research of DIBs outside the Milky Way is
currently very limited. Specifically spatially resolved investigations of DIBs
outside of the Local Group is, to our knowledge, inexistent. Here, we explore
the capability of the high sensitivity Integral Field Spectrograph, MUSE, as a
tool to map diffuse interstellar bands at distances larger than 100 Mpc. We use
MUSE commissioning data for AM 1353-272 B, the member with highest extinction
of the "The Dentist's Chair", an interacting system of two spiral galaxies.
High signal-to-noise spectra were created by co-adding the signal of many
spatial elements distributed in a geometry of concentric elliptical half-rings.
We derived decreasing radial profiles for the equivalent width of the
$\lambda$5780.5 DIB both in the receding and approaching side of the companion
galaxy up to distances of $\sim$4.6 kpc from the center of the galaxy.
Likewise, interstellar extinction, as derived from the Halpha/Hbeta line ratio
displays a similar trend, with decreasing values towards the external parts.
This translates into an intrinsic correlation between the strength of the DIB
and the extinction within AM 1353-272 B consistent with the current existing
global trend between these quantities when using measurements for both Galactic
and extragalactic sight lines. Mapping of DIB strength in the Local Universe as
up to now only done for the Milky Way seems feasible. This offers a new
approach to study the relationship between DIBs and other characteristics and
species of the ISM in different conditions as those found in our Galaxy to the
use of galaxies in the Local Group and/or single sightlines towards supernovae,
quasars and galaxies outside the Local Group.
