0.177      0.018     (7)
  IRAS        12 $\mu$m       0.52       0.02     (8)
  MIPS        24 $\mu$m       2.51       0.03     (9)
  IRAS        25 $\mu$m       2.49       0.03     (8)
  IRAS        60 $\mu$m       6.88       0.04     (8)
  MIPS        70 $\mu$m       4.91       0.49     (9)
  PACS        70 $\mu$m       6.08       0.18     (10)
  IRAS        100 $\mu$m      5.04       0.03     (8)
  PACS        100 $\mu$m      4.97       0.15     (10)
  MIPS        160 $\mu$m      2.01       0.24     (9)
  PACS        160 $\mu$m      2.43       0.12     (10)
  SPIRE       250 $\mu$m     0.633      0.042     (10)
  SPIRE       350 $\mu$m     0.231      0.013     (10)
  SPIRE       500 $\mu$m     0.092      0.008     (10)
  LABOCA      870 $\mu$m     0.040      0.006     (7)
  --------- -------------- ---------- ---------- ------

  : Photometry data.

\(1) [@hayes-2007]; (2) [@tajer-2005]; (3) [@grimes-2009]; (4) [@iglesias-2006]; (5) [@lauberts-1989]; (6) [@jarrett-2000]; (7) [@galametz-2009]; (8) [@soifer-2003]; (9) [@bendo-2012]; (10) [@remy-2012]. \[table:phot\]

Modeling strategy {#sect:model}
=================

Identification of the model components
--------------------------------------

We aim to model the IR emission from all 17 detected lines (except the MIR H$\rm{_2}$ lines which will be modeled in a coming paper) listed in Table \[table:lines\] to understand the conditions of the various media and the dominant processes at work in this low-metallicity starburst. The ISM is very heterogeneous, and over the scale of a galaxy, various phases with a wide range of conditions are mixed together.

In our spectral dataset, 