The Herschel Dwarf Galaxy Survey is a Guaranteed Time Key Program
led by Suzanne Madden.
Abstract:
While much of what we have gleaned of the details of dust and gas properties
and the processes of dust recycling and heating and cooling in galaxies has been
limited to Galactic studies, with Herschel we will be able to explore
these issues in low metallicity dwarf galaxies which are known by now to
exhibit dust and gas properties different from more metal-rich galaxies.
Because these objects are relatively nearby, it is possible to relate the
observed variations in the SEDs to the actual physical phenomena occuring
within the ISM of the galaxy, allowing the construction of a rich
interpretative framework for unresolved, more distant galaxies in the early
universe. Using the SPIRE and PACS instruments on Herschel, we propose to map
the dust and gas in a 50 dwarf galaxies, sampling a broad metallicity range
of 1/50 to 1/2 solar. These data, in conjunction with other ancillary data,
will be used to construct the emission spectrum of the dust plus that of the
gas in the most important cooling lines. The combination of these instruments
onboard Herschel will provide the first opportunity to study the dust and gas
in extremely low metallicity environments that have not yet experienced
repeated recycling through the ISM. The interpretation of this data will
open the door to comprehending primordial ISM conditions and star formation
in the young universe.
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