Theses and Dissertations

Date of Award


Document Type


Degree Name

Master of Science (MS)



First Advisor

Dr. Soumya Mohanty

Second Advisor

Dr. Malik Rakhmanov

Third Advisor

Dr. Soma Mukherjee


The false alarm rate and reduced sensitivity of searches for astrophysical signals are caused by transient signals of earthly origin, or "glitches," in gravitational wave strain data from groundbased detectors. The greater number of observable astrophysical signals will increase the likelihood of glitch overlaps and exacerbate their negative impact for future detectors with higher sensitivities. The wide morphological diversity and unpredictable waveforms of glitches, and with the vast majority of cases lacking supplemental data present the main obstacles to their mitigation. Thus, nonparametric glitch mitigation techniques are required, which should operate for a wide range of glitches and, in the case of overlaps, have little impact on astrophysical signals. The arrangement of free knots is improved to estimate both smooth and non-smooth curves, and wavelet-based shrinkage is added for specific types of glitches in our method for glitch estimation and removal utilizing adaptive spline curve fitting. The effectiveness of the technique is evaluated for seven different kinds of LIGO detector glitch types. In the specific instance of a loud glitch in data from LIGO, Livingston that coincides with the event GW170817, the glitch is evaluated and eliminated without adversely altering the gravitational wave signal. For injected signals overlapped with other kinds of glitches, similar results are observed.


Copyright 2022 Mohammad Abu Thaher Chowdhury. All Rights Reserved.

Included in

Physics Commons