Calibrated and completeness-corrected optical stellar density maps of the Northern Galactic Plane

Abstract

Following on from the second release of calibrated photometry from IPHAS, the INT/WFC Photometric H-alpha Survey of the Northern Galactic Plane, we present incompleteness-corrected stellar density maps in the r and i photometric bands. These have been computed to a range of limiting magnitudes reaching to 20th magnitude in r and 19th in i (Vega system), and with different angular resolutions -- the highest resolution available being 1 square arcminute. The maps obtained cover 94 percent of the 1800 square-degree IPHAS footprint, spanning the Galactic latitude range, -5° < b < +5°, north of the celestial equator. The corrections for incompleteness, due to confusion and sensitivity loss at the faint limit, have been deduced by the method of artificial source injection. The presentation of this method is preceded by a discussion of other more approximate methods of determining completeness. Our method takes full account of position-dependent seeing and source ellipticity in the survey database. The application of the star counts to testing reddened Galactic disc models is previewed by a comparison with predicted counts along three constant-longitude cuts at l $\simeq$ 30°, 90° and 175°: some over-prediction of the most heavily reddened l $\simeq$ 30° counts is found, alongside good agreement at l $\simeq$ 90° and 175°.

arXiv comment25 pages, 23 figures, 3 tables, accepted for publication in MNRAS

References in corpus (23)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• Astropy: A Community Python Package for Astronomy
• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• The Milky Way in Molecular Clouds: A New Complete CO Survey
• Modelling the Galactic Interstellar Extinction Distribution in Three Dimensions
• The Milky Way Tomography with SDSS: II. Stellar Metallicity
• The UKIDSS Galactic Plane Survey
• Three Dimensional Structure of the Milky Way Disk
• The Pan-STARRS 1 Photometric Reference Ladder, Release 12.0
• Outer structure of the Galactic warp and flare: explaining the Canis Major over-density
• Galaxy Disks
• Galaxy Number Counts from the Sloan Digital Sky Survey Commissioning Data
• The VST Photometric Halpha Survey of the Southern Galactic Plane and Bulge (VPHAS+)
• The Second Data Release of the INT Photometric H-Alpha Survey of the Northern Galactic Plane (IPHAS DR2)
• The Besancon Galaxy model renewed I. Constraints on the local star formation history from Tycho data
• Extinction with 2MASS: star counts and reddening toward the North America and the Pelican Nebulae
• A 3D extinction map of the Northern Galactic Plane based on IPHAS photometry
• Confusion errors in astrometry and counterpart association
• Initial Data Release from the INT Photometric H-alpha Survey of the Northern Galactic Plane (IPHAS)
• High Spatial Resolution Galactic 3D Extinction Mapping with IPHAS
• The UV-Excess Survey of the Northern Galactic Plane (UVEX)
• The design and performance of the Gaia photometric system
• 3D Extinction Mapping Using Hierarchical Bayesian Models

Cited by in corpus (5)

• IGAPS: the merged IPHAS and UVEX optical surveys of theNorthern Galactic Plane
• High resolution H-alpha imaging of the Northern Galactic Plane, and the IGAPS images database
• The Gaia/IPHAS and Gaia/KIS Value-Added Catalogues
• Population-based identification of Hα-excess sources in the Gaia DR2 and IPHAS catalogues
• A and F stars as probes of outer Galactic disc kinematics