Noise Based Detection and Segmentation of Nebulous Objects

Abstract

A noise-based non-parametric technique for detecting nebulous objects, for example, irregular or clumpy galaxies, and their structure in noise is introduced. "Noise-based" and "non-parametric" imply that this technique imposes negligible constraints on the properties of the targets and that it employs no regression analysis or fittings. The sub-sky detection threshold is defined and initial detections are found, independently of the sky value. False detections are then estimated and removed using the ambient noise as a reference. This results in a purity level of 0.89 for the final detections as compared to 0.29 for SExtractor when a completeness of 1 is desired for a sample of extremely faint and diffuse mock galaxy profiles. The difference in the mean of the undetected pixels with the known background of mock images is decreased by 4.6 times depending on the diffuseness of the test profiles, quantifying the success in their detection. A non-parametric approach to defining substructure over a detected region is also introduced. NoiseChisel is our software implementation of this new technique. Contrary to the existing signal-based approach to detection, in its various implementations, signal-related parameters such as the image point spread function or known object shapes and models are irrelevant here. Such features make this technique very useful in astrophysical applications such as detection, photometry, or morphological analysis of nebulous objects buried in noise, for example, galaxies that do not generically have a known shape when imaged.

NoiseChisel is part of GNU Astronomy Utilities (see https://www.gnu.org/software/gnuastro/ ). All the data-generated numbers and figures in this paper are now exactly reproducible with a `make' command. See `reproduce/README' in the arXiv source files for details and http://astr.tohoku.ac.jp/~akhlaghi/reproduce/1505.01664/ for up-to-date information. All results generated by free software

References in corpus (11)

• The Cosmic Evolution Survey (COSMOS) -- Overview
• 3D-HST WFC3-selected Photometric Catalogs in the Five CANDELS/3D-HST Fields: Photometry, Photometric Redshifts and Stellar Masses
• Forty-Seven Milky Way-Sized, Extremely Diffuse Galaxies in the Coma Cluster
• Weak Gravitational Lensing with COSMOS: Galaxy Selection and Shape Measurements
• The structure of galactic disks: Studying late-type spiral galaxies using SDSS
• Ultra Low Surface Brightness Imaging with the Dragonfly Telephoto Array
• GALAPAGOS: From Pixels to Parameters
• The Sloan Digital Sky Survey Stripe 82 Imaging Data: Depth-Optimized Co-adds Over 300 Deg^2 in Five Filters
• Intra Cluster Light properties in the CLASH-VLT cluster MACS J1206.2-0847
• MOIRCS Deep Survey. VIII. Evolution of Star Formation Activity as a Function of Stellar Mass in Galaxies since z~3
• Evolution of the Fraction of Clumpy Galaxies at 0.2<z<1.0 in the COSMOS field

Cited by in corpus (107)

• The MUSE Hubble Ultra Deep Field Survey: I. Survey description, data reduction and source detection
• The MUSE Hubble Ultra Deep Field Survey: II. Spectroscopic redshifts and comparisons to color selections of high-redshift galaxies
• Illuminating Low-Surface-Brightness Galaxies with the Hyper Suprime-Cam Survey
• A distance of 13 Mpc resolves the claimed anomalies of the galaxy lacking dark matter
• The formation and evolution of low-surface-brightness galaxies
• The ALMA Spectroscopic Survey in the HUDF: CO Excitation and Atomic Carbon in Star-Forming Galaxies at $z=1-3$
• Galactic cirri in deep optical imaging
• Census and classification of low-surface-brightness structures in nearby early-type galaxies from the MATLAS survey
• The MUSE Hubble Ultra Deep Field Survey X. Ly$\alpha$ Equivalent Widths at $2.9<z<6.6$
• Preparing for low surface brightness science with the Vera C. Rubin Observatory: characterisation of tidal features from mock images
• The Sloan Digital Sky Survey extended point spread functions
• The galaxy "missing dark matter" NGC1052-DF4 is undergoing tidal disruption
• JWST Imaging of Earendel, the Extremely Magnified Star at Redshift $z=6.2$
• LSDCat: Detection and cataloguing of emission-line sources in integral-field spectroscopy datacubes
• Hidden depths in the local Universe: The Stellar Stream Legacy Survey
• The ALMA Spectroscopic Survey in the HUDF: Nature and physical properties of gas-mass selected galaxies using MUSE spectroscopy
• Introducing the LBT Imaging of Galactic Halos and Tidal Structures (LIGHTS) survey. A preview of the low surface brightness Universe to be unveiled by LSST
• Image Subtraction in Fourier Space
• Two lensed star candidates at $z\simeq 4.8$ behind the galaxy cluster MACS J0647.7+7015
• The missing light of the Hubble Ultra Deep Field
• Convergence of Lobatto-type Runge-Kutta methods for partitioned differential-algebraic systems of index 2
• Euclid preparation: XVI. Exploring the ultra low-surface brightness Universe with Euclid/VIS
• A tidal tale: detection of multiple stellar streams in the environment of NGC1052
• The quiescent fraction of isolated low surface brightness galaxies: Observational constraints
• Faint end of the $z\sim 3-7$ luminosity function of Lyman-alpha emitters behind lensing clusters observed with MUSE
• Assessing interstellar comet 3I/ATLAS with the 10.4 m Gran Telescopio Canarias and the Two-meter Twin Telescope
• The edges of galaxies: Tracing the limits of star formation
• A Photometric and Kinematic Analysis of UDG1137+16 (dw1137+16): Probing Ultra-Diffuse Galaxy Formation in a Group Environment
• An evolutionary continuum from nucleated dwarf galaxies to star clusters
• Automated detection of very Low Surface Brightness galaxies in the Virgo Cluster
• Result of the MICROSCOPE Weak Equivalence Principle test
• Optimising and comparing source extraction tools using objective segmentation quality criteria
• Toward Long-Term and Archivable Reproducibility
• Discovery and analysis of low-surface-brightness galaxies in the environment of NGC 1052
• An almost dark galaxy with the mass of the Small Magellanic Cloud
• Euclid: Early Release Observations -- Deep anatomy of nearby galaxies
• Flattened structures of dwarf satellites around massive host galaxies in the MATLAS low-to-moderate density fields
• Exploring the nature of dark matter with the extreme galaxy AGC 114905
• Galaxy and Mass Assembly (GAMA): Extended Intra-Group Light in a group at $z=0.2$ from deep Hyper-Suprime Cam images
• A NOEMA molecular line scan of the Hubble Deep Field North: Improved constraints on the CO luminosity functions and cosmic density of molecular gas
• Dusty spirals triggered by shadows in transition discs
• Beyond Ultra-diffuse Galaxies. I. Mass--Size Outliers among the Satellites of Milky Way Analogs
• A giant umbrella-like stellar stream around the tidal ring galaxy NGC 922
• The Active Asteroids Citizen Science Program: Overview and First Results
• The multifarious ionization sources and disturbed kinematics of extraplanar gas in five low-mass galaxies
• Evolution of compact groups from intermediate to final stages: A case study of the HI content of HCG 16
• Dissecting the RELICS cluster SPT-CLJ0615-5746 through the intracluster light: confirmation of the multiple merging state of the cluster formation
• CAVITY, Calar Alto Void Integral-field Treasury surveY and project extension
• Strategies for optimal sky subtraction in the low surface brightness regime
• Sky Subtraction in an Era of Low Surface Brightness Astronomy
• Extragalactic Stellar Tidal Streams in the Dark Energy Survey
• Massive Early-Type Galaxies in the HSC-SSP: Flux Fraction of Tidal Features and Merger Rates
• Measuring the average molecular gas content of star-forming galaxies at $z=3-4$
• RELICS: ICL Analysis of the $z=0.566$ merging cluster WHL J013719.8-08284
• Galaxy clustering at cosmic dawn from JWST/NIRCam observations to redshift z$\sim$11
• Ultra-deep imaging of NGC1052-DF2 and NGC1052-DF4 to unravel their origins
• MOS spectroscopy of protocluster candidate galaxies at z=6.5
• The AMIGA sample of isolated galaxies. XIV. Disc breaks and interactions through ultra-deep optical imaging
• Observations of two super fast rotator NEAs: 2021 NY${}_1$ and 2022 AB
• Morphology and surface photometry of a sample of isolated early-type galaxies from deep imaging
• A search for stellar tidal streams around Milky Way analogues from the SAGA sample
• Estimating Sky Level
• Discovery and physical characterization as the first response to a potential asteroid collision: The case of 2023 DZ2
• Correlation of structure and stellar properties of galaxies in Stripe 82
• A Recipe for Unbiased Background Modeling in Deep Wide-Field Astronomical Images
• Formation of disc galaxies around z~2
• Extragalactic Stellar Tidal Streams: Observations meet Simulation
• Physical characterization of 2020 AV2, the first known asteroid orbiting inside Venus orbit
• Euclid: Early Release Observations of diffuse stellar structures and globular clusters as probes of the mass assembly of galaxies in the Dorado group
• Euclid: Early Release Observations -- The Intracluster Light of Abell 2390
• Uncovering Tidal Treasures: Automated Classification of Faint Tidal Features in DECaLS Data
• Pre-perihelion Monitoring of Interstellar Comet 2I/Borisov
• Deep view of the intracluster light in the Coma cluster of galaxies
• LIGHTS. A robust technique to identify galaxy edges
• J-PLUS: Spectroscopic validation of H$\alpha$ emission line maps in spatially resolved galaxies
• The truncation of the disk of NGC 4565: Detected up to z=4 kpc, with star formation, and affected by the warp
• Flares, Warps, Truncations, and Satellite: The Ultra-thin Galaxy UGC 11859
• Ultra-Diffuse Galaxies (UDGs) with Hyper Suprime-Cam I: Revised Catalog of Coma Cluster UDGs
• A grand-design spiral galaxy 1.5 billion years after the Big Bang with JWST
• Constraining the top-light initial mass function in the extended ultraviolet disk of M83
• Detection of Faint Sources by the UltraViolet Imaging Telescope Onboard AstroSat Using Poisson Distribution of Background
• STRRINGS: STReams in Residual Images of Nearby GalaxieS
• Hydra I: An extensible multi-source-finder comparison and cataloguing tool
• Stellar tidal streams around nearby spiral galaxies with deep imaging from amateur telescopes
• Characterization of of (98943) 2001 CC${}_{21}$, the target of Hayabusa2$\#$
• Differencing and Coadding JWST Images with Matched Point Spread Function
• Bulgeless Evolution And the Rise of Discs (BEARD) I. Physical drivers of the mass-size relation for Milky Way-like galaxies
• Identifying diffuse spatial structures in high-energy photon lists
• Revisiting the structure of galactic disks with deep imaging
• NASIM: Revealing the low surface brightness Universe from legacy VISTA data
• Deep imaging of the galaxy Malin 2 shows new faint structures and a candidate satellite dwarf galaxy
• A disk and no signatures of tidal distortion in the galaxy "lacking" dark matter NGC 1052-DF2
• Tracing satellite planes in the Sculptor group: II. Discovery of five faint dwarf galaxies in the DESI Legacy Survey
• NEXUS: A Search for Nuclear Variability with the First Two JWST NIRCam Epochs
• J-PAS: Discovery of RaJav, a bright spatially extended Ly$\alpha$ Nebula at z=2.25
• J-PLUS: Turning Off the Bright Stars
• The mysterious Globular Cluster population of MATLAS-2019
• VST-SMASH: VST Survey of Mass Assembly and Structural Hierarchy I. Survey presentation and deep photometry of IC 5332: tracing the mass assembly in the challenging faintest-end regime
• With arms wide open: a VLT/MUSE view of the mechanisms driving unwinding spiral arms in cluster galaxies
• Analysis of Galactic cirrus filaments in HSC-SSP high-resolution deep images using artificial neural networks
• Multiscale exploration of SMACS J0723.3--7327's intracluster light and past dynamical history
• The Fornax Deep Survey (FDS) with the VST: III. Low Surface Brightness (LSB) dwarfs and Ultra Diffuse Galaxies (UDGs) in the center of the Fornax cluster
• Andromeda's tenuous veil: A likely Milky Way nebula projected toward M31
• A Pearl in the Shell: an ultra-compact dwarf within the tidal debris surrounding spiral galaxy NGC 7531
• Galaxy groups in various evolutionary stages
• Discovery of a large and faint nebula at the Triangulum galaxy
• The Exploration of Local VolumE Satellites (ELVES) Survey: A Nearly Volume-Limited Sample of Nearby Dwarf Satellite Systems