Probing the extragalactic fast transient sky at minute timescales with DECam

Abstract

Searches for optical transients are usually performed with a cadence of days to weeks, optimised for supernova discovery. The optical fast transient sky is still largely unexplored, with only a few surveys to date having placed meaningful constraints on the detection of extragalactic transients evolving at sub-hour timescales. Here, we present the results of deep searches for dim, minute-timescale extragalactic fast transients using the Dark Energy Camera, a core facility of our all-wavelength and all-messenger Deeper, Wider, Faster programme. We used continuous 20s exposures to systematically probe timescales down to 1.17 minutes at magnitude limits $g>23$ (AB), detecting hundreds of transient and variable sources. Nine candidates passed our strict criteria on duration and non-stellarity, all of which could be classified as flare stars based on deep multi-band imaging. Searches for fast radio burst and gamma-ray counterparts during simultaneous multi-facility observations yielded no counterparts to the optical transients. Also, no long-term variability was detected with pre-imaging and follow-up observations using the SkyMapper optical telescope. We place upper limits for minute-timescale fast optical transient rates for a range of depths and timescales. Finally, we demonstrate that optical $g$-band light curve behaviour alone cannot discriminate between confirmed extragalactic fast transients such as prompt GRB flashes and Galactic stellar flares.

arXiv commentPublished in MNRAS

References in corpus (85)

• Gaia Data Release 2. Summary of the contents and survey properties
• The Gaia mission
• Multi-messenger Observations of a Binary Neutron Star Merger
• The Supernova Legacy Survey: Measurement of Omega_M, Omega_Lambda and w from the First Year Data Set
• The Zwicky Transient Facility: System Overview, Performance, and First Results
• A bright millisecond radio burst of extragalactic origin
• The Man Behind the Curtain: X-rays Drive the UV through NIR Variability in the 2013 AGN Outburst in NGC 2617
• The Fermi Gamma-Ray Burst Monitor
• The Burst Alert Telescope (BAT) on the Swift MIDEX Mission
• First Results from the Catalina Real-time Transient Survey
• Astrophysics Source Code Library
• Swope Supernova Survey 2017a (SSS17a), the Optical Counterpart to a Gravitational Wave Source
• The Dark Energy Camera
• The Dark Energy Survey: more than dark energy - an overview
• The Electromagnetic Counterpart of the Binary Neutron Star Merger LIGO/VIRGO GW170817. II. UV, Optical, and Near-IR Light Curves and Comparison to Kilonova Models
• LSST Science Book, Version 2.0
• The Zwicky Transient Facility: Science Objectives
• Illuminating Gravitational Waves: A Concordant Picture of Photons from a Neutron Star Merger
• The Emergence of a Lanthanide-Rich Kilonova Following the Merger of Two Neutron Stars
• A "kilonova" associated with short-duration gamma-ray burst 130603B
• Exploring the Optical Transient Sky with the Palomar Transient Factory
• The Host Galaxy and Redshift of the Repeating Fast Radio Burst FRB 121102
• Optical emission from a kilonova following a gravitational-wave-detected neutron-star merger
• Constraining the Age-Activity Relation for Cool Stars: The SDSS DR5 Low-Mass Star Spectroscopic Sample
• The Electromagnetic Counterpart of the Binary Neutron Star Merger LIGO/Virgo GW170817. I. Dark Energy Camera Discovery of the Optical Counterpart
• The Combined Ultraviolet, Optical, and Near-Infrared Light Curves of the Kilonova Associated with the Binary Neutron Star Merger GW170817: Unified Data Set, Analytic Models, and Physical Implications
• SkyMapper and the Southern Sky Survey
• An r-Process Kilonova Associated with the Short-Hard GRB 130603B
• The discovery of the electromagnetic counterpart of GW170817: kilonova AT 2017gfo/DLT17ck
• SkyMapper Southern Survey: First Data Release (DR1)
• Rapidly-Evolving and Luminous Transients from Pan-STARRS1
• The High Time Resolution Universe Pulsar Survey I: System configuration and initial discoveries
• The Sloan Digital Sky Survey Data Release 7 Spectroscopic M Dwarf Catalog I: Data
• Kepler Flares II: The Temporal Morphology of White-Light Flares on GJ 1243
• MASTER optical detection of the first LIGO/Virgo neutron stars merging GW170817
• The Macronova in GRB 050709 and the GRB/macronova connection
• GRB 080503: Implications of a Naked Short Gamma-Ray Burst Dominated by Extended Emission
• The lightcurve of the macronova associated with the long-short burst GRB 060614
• Fast radio bursts: search sensitivities and completeness
• Rapidly evolving transients in the Dark Energy Survey
• Rapidly Decaying Supernova 2010X: A Candidate ".Ia" Explosion
• Rapidly Rising Transients in the Supernova - Superluminous Supernova Gap
• M Dwarfs in SDSS Stripe 82: Photometric Light Curves and Flare Rate Analysis
• FRB microstructure revealed by the real-time detection of FRB170827
• An Unusually Fast-Evolving Supernova
• A luminous blue kilonova and an off-axis jet from a compact binary merger at z=0.1341
• Discovery of Early Optical Emission from GRB 021211
• Precise Throughput Determination of the PanSTARRS Telescope and the Gigapixel Imager using a Calibrated Silicon Photodiode and a Tunable Laser: Initial Results
• The First Hours of the GW170817 Kilonova and the Importance of Early Optical and Ultraviolet Observations for Constraining Emission Models
• The Bright Optical flash and Afterglow from the Gamma-Ray Burst GRB 130427A
• A surge of light at the birth of a supernova
• A hot and fast ultra-stripped supernova that likely formed a compact neutron star binary
• GRB 080503 late afterglow re-brightening: signature of a magnetar powered merger-nova
• The SUrvey for Pulsars and Extragalactic Radio Bursts I: Survey Description and Overview
• M Dwarf Flares from Time-Resolved SDSS Spectra
• The Deep Lens Survey Transient Search I : Short Timescale and Astrometric Variability
• A search for optical bursts from the repeating fast radio burst FRB 121102
• Shock Breakout and Early Light Curves of Type II-P Supernovae Observed with Kepler
• Rapidly Rising Transients from Subaru Hyper Suprime-Cam Transient Survey
• Constraining GRB Emission Physics with Extensive Early-Time, Multiband Follow-up
• The UTMOST: A hybrid digital signal processor transforms the MOST
• iPTF14yb: The First Discovery of a GRB Afterglow Independent of a High-Energy Trigger
• The Blanco Cosmology Survey: An Optically-Selected Galaxy Cluster Catalog and a Public Release of Optical Data Products
• Five new real-time detections of Fast Radio Bursts with UTMOST
• The ASAS-SN Bright Supernova Catalog -- III. 2016
• The ASAS-SN Bright Supernova Catalog $-$ II. 2015
• SN 2015U: A Rapidly Evolving and Luminous Type Ibn Supernova
• A Search for Untriggered GRB Afterglows with ROTSE-III
• A Search for Fast Optical Transients in the Pan-STARRS1 Medium-Deep Survey: M Dwarf Flares, Asteroids, Limits on Extragalactic Rates, and Implications for LSST
• The High Cadence Transient Survey (HiTS) - I. Survey design and supernova shock breakout constraints
• A Search for Kilonovae in the Dark Energy Survey
• Inside catalogs: a comparison of source extraction software
• GRB 120711A: an intense INTEGRAL burst with long-lasting soft gamma-ray emission and a powerful optical flash
• Star-galaxy classification in the Dark Energy Survey Y1 dataset
• Selection Effects, Biases, and Constraints in the Calan/Tololo Supernova Survey
• Exploring the efficacy and limitations of shock-cooling models: new analysis of Type II supernovae observed by the Kepler mission
• The SkyMapper Transient Survey
• iPTF Archival Search for Fast Optical Transients
• Optical Observations of Gamma-Ray Bursts, the Discovery of Supernovae 2005bv, 2005ee, and 2006ak, and Searches for Transients Using the "MASTER" Robotic Telescope
• A Survey for Fast Transients in the Fornax Cluster of Galaxies
• HIPSR: A Digital Signal Processor for the Parkes 21-cm Multibeam Receiver
• Mary, a pipeline to aid discovery of optical transients
• The Palomar Transient Factory Sky2Night programme
• Photometric Flaring Fraction of M dwarf Stars from the SkyMapper Southern Survey
• An Empirical Study of Contamination in Deep, Rapid, and Wide-Field Optical Follow-Up of Gravitational Wave Events

Cited by in corpus (21)

• The Automatic Learning for the Rapid Classification of Events (ALeRCE) Alert Broker
• Fast-transient Searches in Real Time with ZTFReST: Identification of Three Optically-discovered Gamma-ray Burst Afterglows and New Constraints on the Kilonova Rate
• Constraining the Kilonova Rate with Zwicky Transient Facility Searches Independent of Gravitational Wave and Short Gamma-ray Burst Triggers
• The multiwavelength counterparts of fast radio bursts
• Unsupervised machine learning for transient discovery in Deeper, Wider, Faster light curves
• Multiwavelength observations of Fast Radio Bursts
• A high-rate foreground of sub-second flares from geosynchronous satellites
• Optimizing Serendipitous Detections of Kilonovae: Cadence and Filter Selection
• Exploring nine simultaneously occurring transients on April 12th 1950
• The Deeper, Wider, Faster Program: Exploring stellar flare activity with deep, fast cadenced DECam imaging via machine learning
• Contemporaneous X-ray Observations of 30 Bright Radio Bursts from the Prolific Fast Radio Burst Source FRB 20220912A
• Refining the mass estimate for the intermediate-mass black hole candidate in NGC 3319
• High Cadence Optical Transient Searches using Drift Scan Imaging I: Proof of Concept with a Pre-Prototype System
• The Evryscope Fast Transient Engine: Real-Time Detection for Rapidly Evolving Transients
• K2: Background Survey -- the search for undiscovered transients in Kepler/K2 data
• Radio Transients and Variables in the Tenth Deeper, Wider, Faster Observing Run
• Prompt Detection of Fast Optical Bursts with the Vera C. Rubin Observatory
• Detecting the early optical flashes of gamma-ray bursts with small telescope arrays
• Fast estimation of the look-elsewhere effect using Gaussian random fields
• Finding Fast Transients in Real Time Using Novel Light Curve Analysis Algorithm
• Understanding the human in the design of cyber-human discovery systems for data-driven astronomy