Spatially resolved star formation and dust attenuation in Mrk848:
  Comparison of the integral field spectra and the UV-to-IR SED
  We investigate the star formation history and the dust attenuation in the
galaxy merger Mrk848. Thanks to the multiwavelength photometry from the
ultraviolet (UV) to the infrared (IR), and MaNGA's integral field spectroscopy,
we are able to study this merger in a detailed way. We divide the whole merger
into the core and tail regions, and fit both the optical spectrum and the
multi-band spectral energy distribution (SED) to models to obtain the star
formation properties for each region respectively. We find that the color
excess of stars in the galaxy $E(B-V)_s^{SED}$ measured with the multi-band SED
fitting is consistent with that estimated both from the infrared excess (the
ratio of IR to UV flux) and from the slope of the UV continuum. Furthermore,
the reliability of the $E(B-V)_s^{SED}$ is examined with a set of mock SEDs,
showing that the dust attenuation of the stars can be well constrained by the
UV-to-IR broadband SED fitting. The dust attenuation obtained from optical
continuum $E(B-V)_s^{spec}$ is only about half of $E(B-V)_s^{SED}$. The ratio
of the $E(B-V)_s^{spec}$ to the $E(B-V)_g$ obtained from the Balmer decrement
is consistent with the local value (around 0.5). The difference between the
results from the UV-to-IR data and the optical data is consistent with the
picture that younger stellar populations are attenuated by an extra dust
component from the birth clouds compared to older stellar populations which are
only attenuated by the diffuse dust. Both with the UV-to-IR SED fitting and the
spectral fitting, we find that there is a starburst younger than 100~Myr in one
of the two core regions, consistent with the scenario that the
interaction-induced gas inflow can enhance the star formation in the center of
galaxies.
