Small-scale chemical abundance analysis in a blue compact dwarf galaxy
  SBS 1415+437
  We use integral field spectroscopic (IFS) observations from Gemini
Multi-Object Spectrograph-North (GMOS-N) to analyse the ionised gas in the
principal star-forming region in the blue compact dwarf galaxy SBS 1415+437.
The IFS data enable us to map the weak auroral line [O III] $\lambda$4363 at a
spatial scale of $\sim$6.5 pc across a region of $\sim$143 $\times$ 143 pc$^2$.
This in turn allows us to use the robust direct T$_e$-method to map the ionic
and elemental abundances of nitrogen (N) along with the alpha-elements, oxygen
(O), neon (Ne), sulphur (S) and argon (Ar). We utilise these abundances to map
the relative abundances of N, Ne, S and Ar with respect to O. We segment this
predominantly photoionised region of study into elliptical annuli on the basis
of the H$\alpha$ flux distribution to study the variation of chemical
abundances and their ratios, and find no significant chemical variation. We
also perform chemical abundance analysis on the integrated spectra of the
region under study and elliptical annuli within it. We find that the inferred
abundances are in agreement with the median of the abundances obtained from the
chemical abundance maps of the principal star-forming region and the mapped
values within annuli.The finding has important implications for direct
comparison with high-redshift observations, where spatial resolution is not
available, and for a consistent approach to track chemical evolution across
cosmic time.
