Graduate Research
Gulzhaukhar Tukayeva
Title: "Data Conditioning and Removal of Noise Artifacts for Searches of Gravitational Waves"
Mentor: Dr. Soma Mukherjee
The goal of this project is to remove noise artifacts from data in order to obtain gravitational wave signal. Gravitational waves are ripples in the fabric of space-time which are caused by most dynamic and powerful events in the Universe. When massive stellar objects are orbiting each other, they disrupt space-time and radiate the gravitational waves. These ripples propagate at the speed of light through the Universe, carrying with them the information about their sources. On September 14, 2015, Advanced LIGO detectors observed distortions in space-time caused by gravitational waves produced by two colliding black holes 1.3 billion light years away. The Royal Swedish Academy of Sciences awarded physicists Barry Barish, Kip Thorne, Rainer Weiss the Nobel Prize for direct observation of the gravitational waves. Currently, there are three detectors capable of measuring spacetime distortions produced by gravitational waves: two US LIGO detectors and French-Italian Virgo detector. All of them utilize Fabry-Perot-Michelson interferometers that measure strain induced by passing gravitational waves as a varying phase difference between the light propagating in perpendicular arms.
LIGO Hanford (ligo.caltech.edu) Virgo (ligo.caltech.edu)
The goal of this project is to denoise the data, which is contaminated with noise, such as seismic motion, electrical disturbances, magnetic coupling and other instrumental artifacts. This can be done in several steps which include calculation Fourier transform, generation of power spectrum, and filtering of data (low pass and high pass). The next step is whitening, which is followed by line removal. The calculations are done in matlab using the following functions: fftfilt, filter, resample, fir2, rngmed2. Preliminary results of this analysis are shown in the following figures:
Raw data Denoised data