SNID–SAGE: a modern framework for interactive supernova classification and spectral analysis

Monthly Notices of the Royal Astronomical Society Oxford University Press 549:4 (2026) stag1066

Authors:

Fiorenzo Stoppa, Stephen J Smartt

Abstract:

We present SNID–SAGE (SuperNova IDentification–Spectral Analysis and Guided Exploration), a framework for supernova spectral classification with both a fully interactive graphical interface and a scriptable command-line pipeline for large-scale processing. The pipeline combines deterministic spectral pre-processing, FFT-based cross-correlation against a curated template library, ranking of candidate matches using a composite quality metric, and consolidation of redshift and classification solutions into a single result with associated quality and confidence estimates. SNID–SAGE includes an upgradeable template library (about 6000 spectra), interactive line identification with velocity measurements, and optional natural-language summaries of classification results. We evaluate SNID–SAGE using two complementary tests: (i) Leave-one-out cross-validation, in which each template spectrum is matched against the remainder of the library; and (ii) large-scale application to WISeREP spectra with valid coverage across the 4000–7000 Å interval, irrespective of spectral type, comprising approximately 46 000 spectra, with redshift validation against known host-galaxy measurements where available. The full validation results and the SNID–SAGE framework are publicly available, supporting integration into spectroscopic survey workflows.

A Disappearing Act: Constraints From "Missing" Flares of Repeating Partial TDE Candidates

(2026)

Authors:

Jason T Hinkle, Chang Liu, Adam A Miller, Ping Chen, Katie Auchettl, Benjamin J Shappee, Christopher S Kochanek, KZ Stanek, Todd A Thompson

ATLAS100 – I. A volume-limited sample of supernovae and related transients within 100 Mpc

Monthly Notices of the Royal Astronomical Society Oxford University Press 549:4 (2026) stag1028

Authors:

S Srivastav, SJ Smartt, T Moore, KW Smith, DR Young, MD Fulton, CR Angus, M Nicholl, HF Stevance, T-W Chen, A Pastorello, J Sommer, F Stoppa, JW Tweddle, JP Anderson, ME Huber, A Rest, L Rhodes, LJ Shingles, A Aamer, A Clocchiatti, AJ Cooper, N Erasmus, JH Gillanders, D Magill

Abstract:

We present ATLAS100 – a sample of 1729 supernovae and other explosive optical transients within ∼100 Mpc observed by the ATLAS survey over a span of 5.75 yr from 2017 September 21 to 2023 June 21. The volume-limited sample includes transients associated with galaxies with a spectroscopic redshift of , and spectroscopically classified transients within this redshift threshold where a host redshift was not available in existing catalogues. Our host galaxy list is constructed from aggregating all available galaxy redshift and distance catalogues. We carefully select all transients within a projected radius of 50 kpc of these hosts. The ATLAS100 transient sample has a host galaxy redshift completeness fraction of 83 per cent, consistent with expectations for the redshift completeness of local galaxy catalogues. Within this volume, the spectroscopic classifications are 87 per cent complete and we reclassify many ambiguous transients with joint light curve and spectroscopic considerations. Here, we release the catalogue together with compiled, binned, and cleaned ATLAS photometry for all transients. We fit the light curve data to derive peak luminosities and characteristic time-scales. We explore the sample characteristics, demographics, and discuss the completeness and purity of the sample. This is the first in a series of papers that will explore the rates and physical parameters of a complete and large sample of nearby supernovae and transients brighter than .

An analysis of the Type Ia SN 2024gy and a comparison of different host extinction estimation techniques

ArXiv 2606.03589 (2026)

Authors:

Jacco H Terwel, Kate Maguire, Cillian O'Donnell, Miika Pursiainen, Alba Casasbuenas, Julie Thiim Gadeberg, Ben Godson, Luke Harvey, Benjamin Nobre Hauptmann, Niilo Koivisto, Chang Liu, Shravya Shenoy, Samuel Grund Sørensen, María Alejandra Díaz Teodori, Astrid Guldberg Theil, Mikael Turkki, Alaa Alburai, Joe Anderson, Thomas de Boer, Tomás Müller Bravo, Umut Burgaz, Kenneth C Chambers, Ting-Wan Chen, João Duarte, Lluis Galbany, Mariusz Gromadzki, Cosimo Inserra, Joel Johansson, Young-Lo Kim, Thomas Lowe, Eugene Magnier, Rita P Santos, Jesper Sollerman, Richard Wainscoat, David R Young, Tracy X Chen, Matthew J Graham, Mansi M Kasliwal, Frank J Masci, Josiah N Purdum, Ines Belkhodja

Blackholistic 2026 meeting report

(2026)

Authors:

Rob Fender, Jane Dai, Erin Kara, Sera Markoff, Francesca Panessa, Jiri Svoboda, Heino Falcke