The Effelsberg-Bonn HI Survey (EBHIS)

TL;DR

The EBHIS is an all-sky HI survey covering northern sky regions up to z ~ 0.07, utilizing FPGA spectrometers for high-resolution, RFI-resistant data collection, with data accessible for scientific research.

Contribution

This paper presents the design, implementation, and initial results of the EBHIS, a new high-resolution, all-sky HI survey with improved RFI mitigation and data accessibility.

Findings

Surveyed about 8000 square degrees so far

Achieved sensitivity comparable to existing surveys like GASS and HIPASS

Data quality suitable for scientific analysis

Abstract

The Effelsberg-Bonn HI survey (EBHIS) comprises an all-sky survey north of Dec = -5 degrees of the Milky Way and the local volume out to a red-shift of z ~ 0.07. Using state of the art Field Programmable Gate Array (FPGA) spectrometers it is feasible to cover the 100 MHz bandwidth with 16.384 spectral channels. High speed storage of HI spectra allows us to minimize the degradation by Radio Frequency Interference (RFI) signals. Regular EBHIS survey observations started during the winter season 2008/2009 after extensive system evaluation and verification tests. Until today, we surveyed about 8000 square degrees, focusing during the first all-sky coverage of the Sloan-Digital Sky Survey (SDSS) area and the northern extension of the Magellanic stream. The first whole sky coverage will be finished in 2011. Already this first coverage will reach the same sensitivity level as the Parkes Milky Way (GASS) and extragalactic surveys (HIPASS). EBHIS data will be calibrated, stray-radiation corrected and freely accessible for the scientific community via a web-interface. In this paper we demonstrate the scientific data quality and explore the expected harvest of this new all-sky survey.