Understanding the LIGO GW150914 event

TL;DR

This paper introduces a simplified, assumption-light method to extract and confirm the GW150914 gravitational wave event from LIGO data, reproducing the original results and identifying similar signals.

Contribution

It presents a new straightforward technique for signal extraction that does not rely on physical models, enabling independent verification of GW150914.

Findings

Successfully reproduces LIGO's GW150914 detection results

Confirms the event's strong correlation between detectors at 6-7 sigma

Identifies other similar but less correlated events

Abstract

We present a simplified method for the extraction of meaningful signals from Hanford and Livingstone 32 seconds data for the GW150914 event made publicly available by the LIGO collaboration and demonstrate its ability to reproduce the LIGO collaboration's own results quantitatively given the assumption that all narrow peaks in the power spectrum are a consequence of physically uninteresting signals and can be removed. After the clipping of these peaks and return to the time domain, the GW150914 event is readily distinguished from broadband background noise. This simple technique allows us to identify the GW150914 event without any assumption regarding its physical origin and with minimal assumptions regarding its shape. We also confirm that the LIGO GW150914 event is uniquely correlated in the Hanford and Livingston detectors for 4096 second data at the level of $6-7\,\sigma$ with a temporal displacement of $\tau=6.9 \pm 0.4\,$ms. We have also identified a few events that are morphologically close to GW150914 but less strongly cross correlated with it.