Saved in:
Bibliographic Details
Main Authors: Sheng, Xinyue, Pham, Tuan Dung, Zhang, Zichi, Nicholl, Matt, Mai, Thai Son
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2512.14644
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908715498602496
author Sheng, Xinyue
Pham, Tuan Dung
Zhang, Zichi
Nicholl, Matt
Mai, Thai Son
author_facet Sheng, Xinyue
Pham, Tuan Dung
Zhang, Zichi
Nicholl, Matt
Mai, Thai Son
contents With large numbers of transients discovered by current and future imaging surveys, machine learning is increasingly applied to light curve and host galaxy properties to select events for follow-up. However, finding rare types of transients remains difficult due to extreme class imbalances in training sets, and extracting features from host images is complicated by the presence of bright foreground sources, particularly if the true host is faint or distant. Here we present a data augmentation pipeline for images and light curves that mitigates these issues, and apply this to improve classification of Superluminous Supernovae Type I (SLSNe-I) and Tidal Disruption Events (TDEs) with our existing NEEDLE code. The method uses a Similarity Index to remove image artefacts, and a masking procedure that removes unrelated sources while preserving the transient and its host. This focuses classifier attention on the relevant pixels, and enables arbitrary rotations for class upsampling. We also fit observed multi-band light curves with a two-dimensional Gaussian Process and generate data-driven synthetic samples by resampling and redshifting these models, cross-matching with galaxy images in the same class to produce unique but realistic new examples for training. Models trained with the augmented dataset achieve substantially higher purity: for classifications with a confidence of 0.8 or higher, we achieve 75% (43%) purity and 75% (66%) completeness for SLSNe-I (TDEs).
format Preprint
id arxiv_https___arxiv_org_abs_2512_14644
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Attention-Based Preprocessing Framework for Improving Rare Transient Classification
Sheng, Xinyue
Pham, Tuan Dung
Zhang, Zichi
Nicholl, Matt
Mai, Thai Son
Instrumentation and Methods for Astrophysics
High Energy Astrophysical Phenomena
With large numbers of transients discovered by current and future imaging surveys, machine learning is increasingly applied to light curve and host galaxy properties to select events for follow-up. However, finding rare types of transients remains difficult due to extreme class imbalances in training sets, and extracting features from host images is complicated by the presence of bright foreground sources, particularly if the true host is faint or distant. Here we present a data augmentation pipeline for images and light curves that mitigates these issues, and apply this to improve classification of Superluminous Supernovae Type I (SLSNe-I) and Tidal Disruption Events (TDEs) with our existing NEEDLE code. The method uses a Similarity Index to remove image artefacts, and a masking procedure that removes unrelated sources while preserving the transient and its host. This focuses classifier attention on the relevant pixels, and enables arbitrary rotations for class upsampling. We also fit observed multi-band light curves with a two-dimensional Gaussian Process and generate data-driven synthetic samples by resampling and redshifting these models, cross-matching with galaxy images in the same class to produce unique but realistic new examples for training. Models trained with the augmented dataset achieve substantially higher purity: for classifications with a confidence of 0.8 or higher, we achieve 75% (43%) purity and 75% (66%) completeness for SLSNe-I (TDEs).
title Attention-Based Preprocessing Framework for Improving Rare Transient Classification
topic Instrumentation and Methods for Astrophysics
High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2512.14644