Prospects for future studies using deep imaging: Analysis of individual Galactic cirrus filaments

Abstract

The presence of Galactic cirrus is an obstacle for studying both faint objects in our Galaxy and low surface brightness extragalactic structures. With the aim of studying individual cirrus filaments in SDSS Stripe 82 data, we develop techniques based on machine learning and neural networks that allow one to isolate filaments from foreground and background sources in the entirety of Stripe 82 with a precision similar to that of the human expert. Our photometric study of individual filaments indicates that only those brighter than 26 mag arcsec${}^{-2}$ in the SDSS $r$ band are likely to be identified in SDSS Stripe~82 data by their distinctive colours in the optical bands. We also show a significant impact of data processing (e.g. flat-fielding, masking of bright stars, and sky subtraction) on colour estimation. Analysing the distribution of filaments' colours with the help of mock simulations, we conclude that most filaments have colours in the following ranges: $0.55\le g-r\le 0.73$ and $0.01\le r-i\le 0.33$. Our work provides a useful framework for an analysis of all types of low surface brightness features (cirri, tidal tails, stellar streams, etc.) in existing and future deep optical surveys. For practical purposes, we provide the catalogue of dust filaments.

Accepted for publication in MNRAS

References in corpus (16)

• Molecular Cloud Evolution II. From cloud formation to the early stages of star formation in decaying conditions
• The Fractal Density Structure in Supersonic Isothermal Turbulence: Solenoidal versus Compressive Energy Injection
• Satellite Imagery Feature Detection using Deep Convolutional Neural Network: A Kaggle Competition
• The influence of diffuse scattered light I. The PSF and its role to observations of the edge-on galaxy NGC 5907
• The Hi-GAL catalogue of dusty filamentary structures in the Galactic Plane
• Scaling Relations of Compressible MHD Turbulence
• The Sloan Digital Sky Survey extended point spread functions
• Probing interstellar turbulence in cirrus with deep optical imaging: no sign of energy dissipation at 0.01 pc scale
• Learning to Denoise Astronomical Images with U-nets
• GALEX Diffuse Observations of the Sky: The Data
• Revisiting Stephan's Quintet with deep optical images
• Quantified diffuse light in compact groups of galaxies
• The relation between the turbulent Mach number and observed fractal dimensions of turbulent clouds
• The GALEX Ultraviolet Virgo Cluster Survey (GUViCS). V. Ultraviolet diffuse emission and cirrus properties in the Virgo cluster direction
• The relation between the true and observed fractal dimensions of turbulent clouds
• Fractal dimension of optical cirrus in Stripe82