Events Calendar
Searching for the 21-cm Cosmic Dawn Absorption Signal with the LWA
Thursday May 2, 2019
2:00 pm
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Presenter: | Chris DiLullo (UNM) |
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Series: | Center for Astrophysics Research and Technologies Seminar Series | |
Abstract: | As the first stars began to turn on in the Universe, it is believed that their ultraviolet emission affected the state of the surrounding neutral hydrogen and caused it to become an absorber of 21-cm radiation from the cosmic microwave background (CMB). Last year's supposed detection of this 'Cosmic Dawn' absorption profile, reported by the Experiment to Detect the Global EoR Signal (EDGES) collaboration centered at 78 MHz, has sparked much debate in the astronomical community. If validated, this detection has wide ranging implications for the standard cosmological paradigm as the profile is much greater in amplitude and much broader in frequency than theoretical models predict. I will begin with a brief introduction into 21-cm cosmology, discuss the supposed EDGES detection and the wide range of responses from the community, and detail ongoing efforts using the LWA station located at the Sevilleta National Wildlife Refuge (LWA-SV) to validate this detection. LWA-SV is one of only a few telescopes in the world capable of observing in this low frequency band and should offer many advantages over the EDGES instrument. I will detail the current sensitivity limits of LWA-SV and outline a plan for future work which should improve upon these limits. | |
Host: | Gregory Taylor | |
Location: | PAIS-2540, PAIS | |