The Evryscope Fast Transient Engine: Real-Time Detection for Rapidly Evolving Transients
arXiv:2302.10929 · doi:10.3847/1538-4365/acbd41
Abstract
Astrophysical transients with rapid development on sub-hour timescales are intrinsically rare. Due to their short durations, events like stellar superflares, optical flashes from gamma-ray bursts, and shock breakouts from young supernovae are difficult to identify on timescales that enable spectroscopic followup. This paper presents the Evryscope Fast Transient Engine (EFTE), a new data reduction pipeline designed to provide low-latency transient alerts from the Evryscopes, a North-South pair of ultra-wide-field telescopes with an instantaneous footprint covering 38% of the entire sky, and tools for building long-term light curves from Evryscope data. EFTE leverages the optical stability of the Evryscopes by using a simple direct image subtraction routine suited to continuously monitoring the transient sky at minute cadence. Candidates are produced within the base Evryscope two-minute cadence for 98.5% of images, and internally filtered using VetNet, a convolutional neural network real-bogus classifier. EFTE provides an extensible, robust architecture for transient surveys probing similar timescales, and serves as the software testbed for the real-time analysis pipelines and public data distribution systems for the Argus Array, a next generation all-sky observatory with a data rate 62x higher than Evryscope.
arXiv comment28 pages, 18 figures. in press, ApJS
References in corpus (81)
- Astropy: A Community Python Package for Astronomy
- Gaia Data Release 2. Summary of the contents and survey properties
- The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
- The Zwicky Transient Facility: System Overview, Performance, and First Results
- The Man Behind the Curtain: X-rays Drive the UV through NIR Variability in the 2013 AGN Outburst in NGC 2617
- A method for optimal image subtraction
- First Results from the Catalina Real-time Transient Survey
- ATLAS: A High-Cadence All-Sky Survey System
- LIGO: The Laser Interferometer Gravitational-Wave Observatory
- The Palomar Transient Factory: System Overview, Performance and First Results
- Astrometry.net: Blind astrometric calibration of arbitrary astronomical images
- The Dark Energy Survey: more than dark energy - an overview
- Rotation-invariant convolutional neural networks for galaxy morphology prediction
- The Pan-STARRS1 Database and Data Products
- SkyMapper and the Southern Sky Survey
- Correcting systematic effects in a large set of photometric lightcurves
- The Effect of a Strong Stellar Flare on the Atmospheric Chemistry of an Earth-like Planet Orbiting an M dwarf
- The ASAS-SN Catalog of Variable Stars I: The Serendipitous Survey
- SkyMapper Southern Survey: First Data Release (DR1)
- A First Catalog of Variable Stars Measured by the Asteroid Terrestrial-impact Last Alert System (ATLAS)
- Toward High-Precision Astrometry with WFPC2. I. Deriving an Accurate PSF
- The ATLAS All-Sky Stellar Reference Catalog
- Time-Resolved Properties and Global Trends in dMe Flares from Simultaneous Photometry and Spectra
- Superflares on Ordinary Solar-Type Stars
- Proper image subtraction - optimal transient detection, photometry and hypothesis testing
- Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia EDR3 stars brighter than G=18.5
- A New Algorithm For Difference Image Analysis
- GLADE: A Galaxy Catalogue for Multi-Messenger Searches in the Advanced Gravitational-Wave Detector Era
- All-Sky spectrally matched UBVRI-ZY and u'g'r'i'z' magnitudes for stars in the Tycho2 catalog
- Real-bogus classification for the Zwicky Transient Facility using deep learning
- Connecting Flares and Transient Mass Loss Events in Magnetically Active Stars
- Automated Transient Identification in the Dark Energy Survey
- The Zwicky Transient Facility Alert Distribution System
- Machine Learning for the Zwicky Transient Facility
- The Surface UV Environment on Planets Orbiting M-Dwarfs: Implications for Prebiotic Chemistry & Need for Experimental Follow-Up
- Discovery of Early Optical Emission from GRB 021211
- Using Machine Learning for Discovery in Synoptic Survey Imaging
- The Bright Optical flash and Afterglow from the Gamma-Ray Burst GRB 130427A
- The First Naked-Eye Superflare Detected from Proxima Centauri
- A surge of light at the birth of a supernova
- Evryscope science: exploring the potential of all-sky gigapixel-scale telescopes
- Deblending and Classifying Astronomical Sources with Mask R-CNN Deep Learning
- Shock Breakout and Early Light Curves of Type II-P Supernovae Observed with Kepler
- No Such Thing as a Simple Flare: Substructure and QPPs Observed in a Statistical Sample of 20 Second Cadence TESS Flares
- EvryFlare III: Temperature Evolution and Habitability Impacts of Dozens of Superflares Observed Simultaneously by Evryscope and TESS
- Constraining GRB Emission Physics with Extensive Early-Time, Multiband Follow-up
- The ANTARES Astronomical Time-Domain Event Broker
- Real-time Analysis and Selection Biases in the Supernova Legacy Survey
- Image Subtraction in Fourier Space
- Statistical Analysis of Stellar Flares from the First Three Years of TESS Observations
- Intermediate Palomar Transient Factory: Realtime Image Subtraction Pipeline
- Characterizing the Near-UV Environment of M Dwarfs
- 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
- The nature of the DLS fast transients
- GRB 120711A: an intense INTEGRAL burst with long-lasting soft gamma-ray emission and a powerful optical flash
- MASTER: The Mobile Astronomical System of Telescope-Robots
- Low-Cost Access to the Deep, High-Cadence Sky: the Argus Optical Array
- Transient-optimised real-bogus classification with Bayesian Convolutional Neural Networks -- sifting the GOTO candidate stream
- Probing the extragalactic fast transient sky at minute timescales with DECam
- Building the Evryscope: Hardware Design and Performance
- Orbital Foregrounds for Ultra-Short Duration Transients
- Detection of Flare-associated CME Candidates on Two M-dwarfs by GWAC and Fast, Time-resolved Spectroscopic Follow-ups
- Fast optical flares from M dwarfs detected by a one-second-cadence survey with Tomo-e Gozen
- iPTF Archival Search for Fast Optical Transients
- A high-rate foreground of sub-second flares from geosynchronous satellites
- A telescope control and scheduling system for the Gravitational-wave Optical Transient Observer (GOTO)
- Errors When Constraining Hot Blackbody Parameters with Optical Photometry
- Towards a Real-time Transient Classification Engine
- Mary, a pipeline to aid discovery of optical transients
- Rotation periods of TESS Objects of Interest from the Magellan-TESS Survey with multiband photometry from Evryscope and TESS
- The Palomar Transient Factory Sky2Night programme
- Linearized Field Deblending: PSF Photometry for Impatient Astronomers
- A mag Super Flare of An Ultracool Star Detected by System
- Mysterious Dust-emitting Object Orbiting TIC 400799224
- OT 060420: A Seemingly Optical Transient Recorded by All-Sky Cameras
- O'TRAIN: a robust and flexible Real/Bogus classifier for the study of the optical transient sky
- Detectability of optical transients with timescales of sub-seconds
- AutoSourceID-Light. Fast Optical Source Localization via U-Net and Laplacian of Gaussian
- Selection of Burst-like Transients and Stochastic Variables Using Multi-Band Image Differencing in the Pan-STARRS1 Medium-Deep Survey
- Multi-wavelength Photometry and Progenitor Analysis of the Nova V906 Car