LIGO Document T2300234-v2

Believe It or Not: Incorporating Relative Time Delay and Magnification Distributions Predicted by Lens Models into Ranking Possible Sub-Threshold, Strongly-Lensed Candidates

Document #:
LIGO-T2300234-v2
Document type:
T - Technical notes
Other Versions:
Abstract:
We expand upon gravitational-wave analysis by considering the possibility of gravitationally lensed pairs of gravitational waves, a phenomenon that has predominantly been studied in regard to electromagnetic waves. Much of the previously established research in gravitational lensing is extended to lensed gravitational waves due to similarity in behavior to electromagnetic waves. Under the lensing hypothesis, we assume the lensed counterparts are subthreshold due to the relative time delay between paths and consequential demagnification effects. The database of registered gravitational waves are considered potential super-threshold events, and the parameters of our search pipeline are altered so subthreshold events significant to the original waveform are registered as a trigger. We do this using the gstLAL-based TESLA search pipeline, which increases the likelihood of detecting these subthreshold events by optimizing the template bank and considering only templates capable of recovering the posterior samples given by Bayes probability distribution. The results are then ranked by the likelihood of the signal being astrophysical in origin and logged for further analysis to determine if they are a lensed counterpart. We aim to improve the TESLA method by modifying the search pipeline's code to produce a ranked list according to lens model. This is done by altering the effective distances to gain information on potential lensed counterparts and assessing the behavior of gravitational waves in various lens models. We will then determine the overall performance change in a final simulation campaign.
Files in Document:
  • Final Report (haley_ligo_surf_final_report.pdf, file is not accessible)
Other Files:
Keywords:
SURF23

DCC Version 3.4.3, contact Document Database Administrators