With the successive improvement of the LIGO sensitivity, the noise in LIGO data suffers from transient noise artefacts, also known as glitches. Often, they are of unknown origin, so removing them is not always possible. The existing short-duration modelled/unmodeled searches often get compromised due to these loud glitches. Special signal-noise discriminators are designed to minimise the impact of the glitches. In addition, the LIGO data also contains strong, nearly sinusoidal features that affect searches for long-duration gravitational wave (GW) signals. All these noise features also change over time due to the complex interaction between the various parts of a GW detector and its environment. The efforts to understand and mitigate such noise artifacts in the instrument and in the data are collectively called detector characterization.

Detector characterization is essential for improving the detector performance and thus improving the sensitivity of GW searches. Even though there is a large community in India specializing in developing search algorithms, analyzing, and modeling GW signals, a few people are working on the GW detector characterization. Having more people working on detector characterization becomes even more crucial in the context of the upcoming LIGO-India detector. This workshop aims to introduce various aspects of detector characterization and tools and encourage the Indian GW community to undertake research problems related to detector characterization, which is crucial during the commissioning phase of LIGO India.

Objectives of the Event:

1. Introducing various tasks under the GW detector characterization activities.
2. Introducing data analysis tools, such as GWpy and Omicron, used for diverse tasks to study and investigate issues about the data.
3. Introducing open questions related to the detector characterisation, e.g., origins of noisy transients such as the long-standing problem of blip glitches

Venue: IUCAA, Pune
Date: December 15 - 19, 2025

Target Audience: Faculty, Scientific Staff, Ph.D. students, Postdocs, and possibly exceptional Master's students.

Scientific Organising Committee:

• Prof. R. Srianand (IUCAA)
• Prof. Sanjit Mitra(IUCAA)
• Prof. Shasvath Kapadia (IUCAA)
• Dr. Suresh Doravari (IUCAA)
• Dr. Shivaraj Kandhasamy (IUCAA)
• Dr. Manasadevi Thirugnanasambandam (IUCAA)
• Dr. Saravanan T. R. (IUCAA)

Image Credit: NASA, ESA, J. Mack (STScI) and J. Madrid (Australian Telescope National Facility)