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Yi Qiu

Ph.D. student in Physics Department of Pennsylvania State University.

Testing the uncertainty of overtone models

In the summer of 2021, I have been doing a remote internship in AEI about ringdown phase gravitational waves and overtone models, which is a very unique and intersting channel of stdy since it is highly related to several approaches to test general relativity. I have spent a quite long time and passion doing this, while thanking to my opportunity to have 2 advisors in this journey, I successfully extract some novel results from this work and now it is going to become my first publication (draft already completed in October\(^{[1]}\)). Here I would give only the abstract down here:

Abstract

The ringdown phase gravitational waves are extremely useful for the testings of general relativity (GR). While distinguishable ringdown signals are required to constrain modified theories of gravity, the particular considerations on the uncertainties inside overtone models are often absent. We investigate the uncertainties of overtone models in both the QNMs' deviation to Kerr spectrum and perturbation. Using our novel grid methods to replace part of the fitting, the results can present in a very comprehensive way while providing extra information on the recovery consistency of final mass and spin of the remnant black hole. Throughout this work, a GW150914-like waveform data BBH:0305 from the SXS catalogue is mostly used. We found very high uncertainties in the highest overtone of models while the fundamental tone can be better constraint with more overtones included. Our results of the 0, 1 tone perturbed model with the optimal fractional deviation factors: \(\alpha_0=-0.04\), \(\beta_0=0.08\), \(\alpha_1=-0.24\), \(\beta_1=0.48\) also give a new reference for the realistic gravitational waves testing of GR by providing the intrinsic uncertainty ranges of the overtone models in 2 tone black hole spectroscopic analysis without assuming specific priors.

While you can see also below -- a beamer I made primarily for the final oral presentation in AEI summer intern which might contains several figures I also used in my paper.

(I would personally recommend this beamer theme I used -- "footfullcite", since it can present the reference clearly in the lower part of each frame where it is cited.)

Reference

[1] Yi Qiu, Xisco Jiménez Forteza, Pierre Mourier. "Testing the uncertainty of overtone models." (will be submitted to Physical Review D in December).