A Caltech Library Service

The Deeper, Wider, Faster programme: exploring stellar flare activity with deep, fast cadenced DECam imaging via machine learning

Webb, S. and Flynn, C. and Cooke, J. and Zhang, J. and Mahabal, A. A. and Abbott, T. M. C. and Allen, R. and Andreoni, I. and Bird, S. A. and Goode, S. and Lochner, M. and Pritchard, T. (2021) The Deeper, Wider, Faster programme: exploring stellar flare activity with deep, fast cadenced DECam imaging via machine learning. Monthly Notices of the Royal Astronomical Society, 506 (2). pp. 2089-2103. ISSN 0035-8711. doi:10.1093/mnras/stab1798.

[img] PDF - Published Version
See Usage Policy.

[img] PDF - Accepted Version
See Usage Policy.


Use this Persistent URL to link to this item:


We present our 500 pc distance-limited study of stellar flares using the Dark Energy Camera as part of the Deeper, Wider, Faster programme. The data were collected via continuous 20-s cadence g-band imaging and we identify 19 914 sources with precise distances from Gaia DR2 within 12, ∼3 deg², fields over a range of Galactic latitudes. An average of ∼74 min is spent on each field per visit. All light curves were accessed through a novel unsupervised machine learning techniques designed for anomaly detection. We identify 96 flare events occurring across 80 stars, the majority of which are M dwarfs. Integrated flare energies range from ∼10³¹–10³⁷ erg, with a proportional relationship existing between increased flare energy with increased distance from the Galactic plane, representative of stellar age leading to declining yet more energetic flare events. In agreement with previous studies we observe an increase in flaring fraction from M0 to M6 spectral types. Furthermore, we find a decrease in the flaring fraction of stars as vertical distance from the galactic plane is increased, with a steep decline present around ∼100 pc. We find that ∼70 per cent of identified flares occur on short time-scales of <8 min. Finally, we present our associated flare rates, finding a volumetric rate of 2.9 ± 0.3 × 10⁻⁶ flares pc⁻³ h⁻¹.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Webb, S.0000-0003-2601-1472
Flynn, C.0000-0003-1110-0712
Cooke, J.0000-0001-5703-2108
Mahabal, A. A.0000-0003-2242-0244
Andreoni, I.0000-0002-8977-1498
Goode, S.0000-0002-9575-5152
Lochner, M.0000-0003-2221-8281
Pritchard, T.0000-0002-4372-8128
Additional Information:© 2021 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model ( Accepted 2021 June 17. Received 2021 June 15; in original form 2021 April 20. Published: 28 June 2021. We would like to acknowledge and thank our reviewer for their very insight and helpful review and comments. Part of this research was funded by the Australian Research Council Centre of Excellence for Gravitational Wave Discovery (OzGrav), CE170100004. JC acknowledges funding by the Australian Research Council Discovery Project, DP200102102. We acknowledge the financial assistance of the National Research Foundation (NRF). Opinions expressed and conclusions arrived at, are those of the authors and are not necessarily to be attributed to the NRF. This work was partly supported by the GROWTH (Global Relay of Observatories Watching Transients Happen) project funded by the National Science Foundation under PIRE Grant No. 1545949. SAB acknowledges support from the Aliyun Fellowship and Chinese Academy of Sciences President’s International Fellowship Initiative Grant. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa. int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa. int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. This project used data obtained with the Dark Energy Camera (DECam), which was constructed by the Dark Energy Survey (DES) collaboration. Funding for the DES Projects has been provided by the U.S. Department of Energy, the U.S. National Science Foundation, the Ministry of Science and Education of Spain, the Science and Technology Facilities Council of the United Kingdom, the Higher Education Funding Council for England, the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign, the Kavli Institute of Cosmological Physics at the University of Chicago, the Center for Cosmology and Astro-Particle Physics at the Ohio State University, the Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University, Financiadora de Estudos e Projetos, Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, Conselho Nacional de Desenvolvimento Científico e Tecnológico and the Ministério da Ciência, Tecnologia e Inovacão, the Deutsche Forschungsgemeinschaft, and the Collaborating Institutions in the Dark Energy Survey. The Collaborating Institutions are Argonne National Laboratory, the University of California at Santa Cruz, the University of Cambridge, Centro de Investigaciones Enérgeticas, Medioambientales y Tecnológicas-Madrid, the University of Chicago, University College London, the DES-Brazil Consortium, the University of Edinburgh, the Eidgenössische Technische Hochschule (ETH) Zürich, Fermi National Accelerator Laboratory, the University of Illinois at Urbana-Champaign, the Institut de Ciències de l’Espai (IEEC/CSIC), the Institut de Física d’Altes Energies, Lawrence Berkeley National Laboratory, the Ludwig-Maximilians Universität München and the associated Excellence Cluster Universe, the University of Michigan, the National Optical Astronomy Observatory, the University of Nottingham, the Ohio State University, the OzDES Membership Consortium the University of Pennsylvania, the University of Portsmouth, SLAC National Accelerator Laboratory, Stanford University, the University of Sussex, and Texas A&M University. This study is based on observations at Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory which is operated by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. SW and SG would like to thank their greyhound Lucy for being a great listener to science conversations, and eater of all the treats. Data Availability: The data underlying this article will be shared on reasonable request to the corresponding author.
Funding AgencyGrant Number
Australian Research CouncilCE170100004
Australian Research CouncilDP200102102
National Research Foundation (South Africa)UNSPECIFIED
Aliyun FellowshipUNSPECIFIED
Chinese Academy of SciencesUNSPECIFIED
Gaia Multilateral AgreementUNSPECIFIED
Department of Energy (DOE)UNSPECIFIED
Ministerio de Ciencia e Innovación (MCINN)UNSPECIFIED
Science and Technology Facilities Council (STFC)UNSPECIFIED
Higher Education Funding Council for EnglandUNSPECIFIED
University of Illinois Urbana-ChampaignUNSPECIFIED
University of ChicagoUNSPECIFIED
Ohio State UniversityUNSPECIFIED
Texas A&M UniversityUNSPECIFIED
Financiadora de Estudos e Projetos (FINEP)UNSPECIFIED
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)UNSPECIFIED
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)UNSPECIFIED
Ministério da Ciência, Tecnologia, Inovações e Comunicações (MCTIC)UNSPECIFIED
Deutsche Forschungsgemeinschaft (DFG)UNSPECIFIED
Argonne National LaboratoryUNSPECIFIED
University of California Santa CruzUNSPECIFIED
University of CambridgeUNSPECIFIED
Centro de Investigaciones Energéticas, Medioambientales y TecnológicasUNSPECIFIED
Medioambientales y Tecnológicas-MadridUNSPECIFIED
University College LondonUNSPECIFIED
DES-Brazil ConsortiumUNSPECIFIED
University of EdinburghUNSPECIFIED
Fermi National Accelerator LaboratoryUNSPECIFIED
Institut de Ciències de l'Espai (IEEC/CSIC)UNSPECIFIED
Institut de Física d’Altes EnergiesUNSPECIFIED
Lawrence Berkeley National LaboratoryUNSPECIFIED
Ludwig-Maximilians Universität MünchenUNSPECIFIED
Excellence Cluster UniverseUNSPECIFIED
University of MichiganUNSPECIFIED
National Optical Astronomy Observatory (NOAO)UNSPECIFIED
University of NottinghamUNSPECIFIED
OzDES Membership ConsortiumUNSPECIFIED
University of PennsylvaniaUNSPECIFIED
University of PortsmouthUNSPECIFIED
Stanford Linear Accelerator CenterUNSPECIFIED
Stanford UniversityUNSPECIFIED
University of SussexUNSPECIFIED
Subject Keywords:methods: data analysis – parallaxes – stars: flare – stars: low-mass
Issue or Number:2
Record Number:CaltechAUTHORS:20211027-173437908
Persistent URL:
Official Citation:S Webb, C Flynn, J Cooke, J Zhang, A Mahabal, T M C Abbott, R Allen, I Andreoni, S A Bird, S Goode, M Lochner, T Pritchard, The Deeper, Wider, Faster programme: exploring stellar flare activity with deep, fast cadenced DECam imaging via machine learning, Monthly Notices of the Royal Astronomical Society, Volume 506, Issue 2, September 2021, Pages 2089–2103,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:111664
Deposited By: Tony Diaz
Deposited On:28 Oct 2021 21:44
Last Modified:28 Oct 2021 21:44

Repository Staff Only: item control page