SETHI@Berkeley- A Piggyback 21-cm Sky Survey at Arecibo

TL;DR

This paper presents a high-resolution, sensitive 21-cm sky survey using the Arecibo telescope, accumulating extensive HI spectra over 2.6 years to enhance astronomical observations.

Contribution

It introduces a novel piggyback survey method at Arecibo that significantly improves angular resolution and sensitivity compared to previous surveys.

Findings

Collected 2.6 years of HI spectra data

Achieved higher angular resolution than prior surveys

Provided better sensitivity than existing interferometric surveys

Abstract

SETI@home observes a 2.5 MHz bandwidth centered on 1420 MHz near the 21-cm line using a short line feed at Arecibo which provides a 6' beam. This feed sits on Carriage House 1. During normal astronomical observations with the new Gregorian dome the feed scans across the sky at twice the sidereal rate. We are using the SETI@home receiver to obtain about 4.4x10^6 HI spectra per year with integration time of 5 seconds per spectrum. We have accumulated 2.6 years of data covering most of the sky observable from Arecibo. This survey has much better angular resolution than previous single dish surveys and better sensitivity than existing or planned interferometric surveys.