Spatially resolved properties of the grand-design spiral galaxy UGC
  9837: a case for high-redshift 2D observations
  Context. We carry out a detailed 2D study of the ionised gas in the local
universe galaxy UGC9837. In nearby galaxies, like the galaxy in question here,
the spatial distribution of the physical properties can be studied in detail,
providing benchmarks for galaxy formation models.
  Aims. Our aim is to derive detailed and spatially resolved physical
properties of the ionised gas of UGC 9837. In addition, we derive an integrated
spectrum of the galaxy and study how varying spatial coverage affects the
derived integrated properties. We also study how the same properties would be
seen if the galaxy was placed at a higher redshift and observed as part of one
of the high-z surveys.
  Methods. UGC9837 was observed using the PMAS PPAK integral field unit. The
spectra are reduced and calibrated and the stellar and ionised components
separated. Using strong emission line ratios of the ionised gas, the source of
ionisation, the dust extinction, the star formation rate, the electron density
and the oxygen abundance derived from a total integrated spectrum, central
integrated spectrum and individual fibre spectra are studied. Finally, the same
properties are studied in a spectrum whose spatial resolution is degraded to
simulate high-z observations.
  Results. The spatial distribution of the ionised gas properties is consistent
with inside-out growing scenario of galaxies. We also find that lack of spatial
coverage would bias the results derived from the integrated spectrum leading,
e.g., to an under-estimation of ionisation and over-estimation of metallicity,
if only the centre of the galaxy was covered by the spectrum. Our simulation of
high-z observations shows that part of the spatial information, such as dust
and SFR distribution would be lost while shallower gradients in metallicity and
ionisation strength would be detected.
