Initial Data Release from the INT Photometric H-alpha Survey of the Northern Galactic Plane (IPHAS)

TL;DR

The IPHAS initial data release provides a comprehensive photometric catalog of about 200 million objects in the northern Galactic plane, enabling large-scale structure studies and stellar population analysis through accessible virtual observatory tools.

Contribution

This paper introduces the first data release of IPHAS, offering a vast, publicly accessible photometric dataset with integrated VO access, setting a new standard for survey data sharing.

Findings

Catalog contains ~200 million objects covering 1600 sq. degrees.

Validated calibration through cross-matching with UKIDSS data.

Demonstrated VO-based data access and analysis capabilities.

Abstract

The INT/WFC Photometric H-alpha Survey of the Northern Galactic Plane (IPHAS) is an imaging survey being carried out in H-alpha, r' and i' filters, with the Wide Field Camera (WFC) on the 2.5-metre Isaac Newton Telescope (INT) to a depth of r'=20 (10 sigma). The survey is aimed at revealing large scale structure in our local galaxy, and also the properties of key early and late populations making up the Milky Way. Mapping emission line objects enables a particular focus on objects in the young and old stages of stellar evolution ranging from early T-Tauri stars to late planetary nebulae. In this paper we present the IPHAS Initial Data Release, primarily a photometric catalogue of about 200 million unique objects, coupled with associated image data covering about 1600 square degrees in three passbands. We note how access to the primary data products has been implemented through use of standard virtual observatory publishing interfaces. Simple traditional web access is provided to the main IPHAS photometric catalogue, in addition to a number of common catalogues (such as 2MASS) which are of immediate relevance. Access through the AstroGrid VO Desktop opens up the full range of analysis options, and allows full integration with the wider range of data and services available through the Virtual Observatory. The IDR represents the largest dataset published primarily through VO interfaces to date, and so stands as an examplar of the future of survey data mining. Examples of data access are given, including a cross-matching of IPHAS photometry with sources in the UKIDSS Galactic Plane Survey that validates the existing calibration of the best data.