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Simulating the Deep Lens Survey at UC Davis

The simulated stars and galaxies from my DLS simulation I created during my 2006 physics REU.

During the summer of 2006, I participated in a physics REU at UC Davis. I worked for Tony Tyson in the UC Davis cosmology group. Tony Tyson worked on the Deep Lens Survey and is director of the upcoming Large Synoptic Survey Telescope. These experiments use weak gravitational lensing to infer the distribution of dark matter in the universe.

A group photo for the 2006 UC Davis physics REU. You can see me
third from the right. Photo from

During the REU, I helped build a computer simulation of the DLS to quantify possible sources of systematic error. The simulation realistically models the density of stars and galaxies in the universe with realistic energy distributions. It allows the galaxies to be distorted by an input dark matter distribution and it realistically simulates the atmospheric point spread function and atmospheric noise. It separately simulates the 8 CCD chips that make up the detector and it simulates the astronomical process of dithering where multiple exposures at slight offsets are coadded together. For increased efficiency, I wrote the simulation so that it could be run in parallel on the computer cluster at Davis. Using the simulated data, I measured the dark matter signal in the simulated data and compared it to the signal in the Monte Carlo distribution.

You can read the paper I wrote at the end of the summer summarizing my work here.

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