[Research]

Thermal dust emission remains a dominant systematic for CMB polarization experiments, and are a critical blockade for precise measurements of B-mode polarization. We developed statistical models of thermal dust emission in order to test the limits of commonly used component separation techniques. We showed that a modified blackbody-based model results in relatively unbiased CMB fits. However, if an emission model with a distribution in the dust polarization is introduced, the resulting recovered CMB amplitudes can be severely biased. Our work adds to the emerging awareness that deviations in the thermal dust polarization angle can severely reduce the precision of CMB measurements.

An emerging technique for probing the high redshift universe, line intensity mapping (LIM) observes wide swathes of the sky at low resolution, thereby enabling new analyses of large scale structure in the early universe. This is done for a variety of spectral lines, where the rest frequency is known. Then, by exploiting the relationship between observed frequency and the distance of the source, the redshift of the emission can be inferred. We investigated the potential for combining observations of differing candidate lines (i.e. 21cm, CII, and OIII) by developing a statistical framework for estimators built using multiple crosscorrelations. (in prep)

I am also a member of the Hydrogen Epoch of Reionization Array (HERA), a radio interferometer. Located in the Karoo Desert, South Africa, it recently placed the current most stringent upper limits on the 21cm power spectrum at redshifts z=7.9 and z=10.4. As part of the validation team, I help test the HERA analysis pipeline to ensure it produces expected results under a variety of scenarios.

Photo courtesy of SARAO

In addition to the work laid out here, I continue to be interested in mitigation of radio frequency foreground, as well as combining multiple cosmological probes in order to maximally extract information from high-redshift observations and improve our understanding of both the early universe, and fundamental physics. Stay tuned!