ALMA unveils high redshift cosmic microscopes discovered by the South Pole Telescope
Joaquin Vieira
Caltech
The South Pole Telescope has systematically identified large numbers
of high-redshift strongly gravitationally lensed systems. These sources
are selected by their extreme mm flux, which is largely independent of
redshift and lensing configuration. I will report results from the first
blind redshift survey undertaken with the recently commissioned Atacama
Large Millimeter Array (ALMA). We targeted 26 extraordinarily bright
and dusty sources selected from a 2500 deg^2 mm survey conducted by the
SPT and obtained redshifts via molecular carbon monoxide (CO) lines. We
determine that roughly 40% of these sources lie at z>4, indicating that we
have uncovered the missing high-redshift tail of starburst galaxies. Two
sources are at z>5.6, placing them among the highest redshift starbursts
known, and indicating that large reservoirs of dust can be present
in massive galaxies at the end of the epoch of cosmic reionization.
These sources were additionally targeted with high resolution imaging with
ALMA, unambiguously demonstrating them to be strongly gravitationally
lensed by foreground structure. We are undertaking a comprehensive and
systematic followup campaign to use these "cosmic magnifying glasses" to
study the infrared background in unprecedented detail, conduct detailed
investigations of the properties of massive galaxies at z~1, inform
the condition of the interstellar medium in starburst galaxies at high
redshift, and place limits on dark matter substructure. I will discuss
the scientific context and potential for these strongly lensed starburst
galaxies, give an overview of our team's extensive followup efforts,
and describe our preliminary science results.
Date: | Mardi, le 4 septembre 2012 |
Heure: | 16:00 |
Lieu: | Université McGill |
| Ernest Rutherford Physics Building, R.E. Bell Conference Room (room 103) |
Contact: | Robert Rutledge |
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