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Published in The Astrophysical Journal, 2012
Galaxy-galaxy lensing in the Deep Lens Survey.
Recommended citation: Choi, A., Tyson, J. A., Morrison, C. B., et al. (2012). "Galaxy-Mass Correlations on 10 Mpc Scales in the Deep Lens Survey" ApJ, 759, 101 https://arxiv.org/abs/1208.3904
CFHTLenS and RCSLenS: testing photometric redshift distributions using angular cross-correlations with spectroscopic galaxy surveys
Published in Monthly Notices of the Royal Astronomical Society, 2016
Constraining photometric redshift distributions using spectroscopic and photometric angular cross-clustering.
Recommended citation: Choi, A., Heymans, C., Blake, C., et al. (2016). "CFHTLenS and RCSLenS: Testing Photometric Redshift Distributions Using Angular Cross-Correlations with Spectroscopic Galaxy Surveys" MNRAS, 463, 3737 https://arxiv.org/abs/1512.03626
Published in arXiv, 2020
Description of the Dark Energy Survey “Deep Fields” which underpin the DES cosmology “Deep + Wide” approach.
Recommended citation: Hartley, W. G., Choi, A., Amon, A., et al. 2020, submitted to MNRAS https://arxiv.org/abs/2012.12824
A synthetic Roman Space Telescope High-Latitude Imaging Survey: simulation suite and the impact of wavefront errors on weak gravitational lensing
Published in Monthly Notices of the Royal Astronomical Society, 2021
Presents weak lensing image simulations for the Roman Space Telescope and a demonstration of the impact of wavefront errors.
Recommended citation: Troxel, M.~A., Long, H., Hirata, C.~M., et al. 2021, MNRAS, 501, 2044 https://arxiv.org/abs/1912.09481
The Wide Field Infrared Survey Telescope (WFIRST) is an upcoming NASA observatory that will investigate the origins of cosmic acceleration using weak gravitational lensing. WFIRST will perform galaxy shape measurements using Teledyne H4RG-10 detectors; thus it is essential to understand inter-pixel non-linearities like the brighter-fatter effect (BFE) and non-linear inter-pixel capacitance (NL-IPC) that could cause systematic errors in the lensing analysis. The non-destructive readout capability of the H4RG-10 detectors enables correlation measurements on flat field data not only between pixels but also between time frames. In this talk, I will present a correlation analysis of flat field data (obtained from the Detector Characterization Laboratory) for one of the WFIRST prototype detectors. After correcting for classical non-linearity, we find a statistically significant residual correlation signal. We leverage the time dimension of this data set to perform some tests that suggest that the BFE is the dominant mechanism. The flat field statistics continue to provide a wealth of information that will eventually help us calibrate WFIRST data and obtain accurate cosmological parameters.
Undergraduate Introductory Physics 7A/B, University of California at Davis, Physics Department, 2004
Over three quarters from Fall, 2004 through Spring, 2005, I led 5 Discussion/Lab sections (each ~25 students) for Physics 7A/B, which is an introductory undergraduate course for pre-meds and students majoring in other STEM fields aside from physics.
Observing Lab, University of California at Davis, Physics, 2005
I led the lab component of Astro 10, which was an introductory course in astronomy for undergraduates. At the beginning of each meeting, I delivered a quick lecture (~30 minutes), for which I created the slides. We then went on to observe and complete exercises using small telescopes on the rooftop of the Physics Building.
Graduate course, University of Edinburgh, 2015
This was a 10 week course that I organized. I also presented 4 of the 10 lectures and arranged for guest lecturers from the Royal Observatory of Edinburgh to lead the rest.