Spectroscopic Quasar Anomaly Detection (SQuAD) Project

Welcome to the SQuAD Project!

The Spectroscopic Quasar Anomaly Detection (SQuAD) Project is dedicated to identifying anomalous quasars from large-scale spectroscopic surveys and conducting follow-up studies on these intriguing sources. Our mission is to uncover rare quasar phenomena to enhance our understanding of supermassive black holes and the extreme environments they inhabit.

About the Project

Quasars are among the brightest and most energetic objects in the universe, powered by supermassive black holes at the centers of distant galaxies. While many quasars have been studied extensively, anomalous quasars—those with unusual spectral characteristics—offer unique insights into astrophysical processes.

Project 1 : Spectroscopic Quasar Anomaly Detection (SQuAD) I: Rest-Frame UV Spectra from SDSS DR16 : The Spectroscopic Quasar Anomaly Detection (SQuAD 1) project is designed to identify and categorize spectroscopically anomalous quasars from large-scale astronomical surveys, such as the SDSS DR16 catalog. By utilizing advanced techniques like Principal Component Analysis (PCA) for dimensionality reduction and hierarchical K-Means clustering, the project focuses on finding rare or unusual quasars with distinct properties. In this first phase, SQuAD 1 concentrates on rest-frame UV spectra to detect anomalies in quasar spectra.

Anomalous Quasar Clusters Visualization

Figure: Visualization of Anomalous Quasar Clusters

The Team

Dr. Vivek M

Principal Investigator

Arihant Tiwari

VSP Student @ IIA | BSMS Physics and Data Science @ IISER Bhopal

Publications

List of research papers and articles published in journals.

Title: Spectroscopic Quasar Anomaly Detection (SQuAD) I: Rest-Frame UV Spectra from SDSS DR16

Authors: Arihant Tiwari, M. Vivek

Journal: Astronomy and Astrophysics (A&A)

Published: Submitted

Download Paper

Download Catalogs

Access our curated catalogs of anomalous quasars identified through the SQuAD Project.

SQuAD Project 1: Rest-frame UV spectra from SDSS DR16 Quasar Catalog

Released: October 1, 2024

Download Link (Will be updated soon !)

Description: Contains a list of 1800 anomalous quasars with spectral data from the SDSS DR16 surveys.

Note: If you are using these catalogs, we would appreciate your citing the SQuAD Project 1 (Tiwari et. al. 2024, A&A) in any publications or presentations that utilize this data.

Contact Us

Have questions or are interested in collaborating? We'd love to hear from you!