Seoul National University Bright Quasar Survey in Optical (SNUQSO) I: First Phase Observations and Results

TL;DR

This paper reports the first phase results of the SNUQSO survey, which aims to identify bright quasars missed by previous surveys, using optical, near-infrared, radio, and X-ray data, and presents spectroscopic observations of 55 candidates.

Contribution

It introduces a new survey targeting bright quasars with diverse selection methods and provides initial spectroscopic results, highlighting the near-completeness of existing bright quasar catalogs.

Findings

14 quasars/Seyferts identified from 55 candidates

Discovery of a bright quasar with i=14.98 mag at z=0.092

Bright quasars remain challenging to find in high Galactic latitude regions

Abstract

We present results from the first phase of the Seoul National University Bright Quasar Survey in Optical (SNUQSO) as well as its basic observational setup. Previous and current large-area surveys have been successful in identifying many quasars, but they could have missed bright quasars due to their survey design. In order to help complete the census of bright quasars, we have performed spectroscopic observations of new bright quasar candidates selected from various methods based on optical colors, near-infrared colors, radio, and X-ray data. In 2005/2006, we observed 55 bright quasar candidates using the Bohyunsan Optical Echelle Spectrograph (BOES) on the 1.8 m telescope at the Bohyunsan Optical Astronomy Observatory in Korea. We identify 14 quasars/Seyferts from our observation, including an optically bright quasar with i=14.98 mag at z=0.092 (SDSS J003236.59-091026.2). Non-quasar/Seyfert objects are found to be mostly stars, among which there are five M-type stars and one cataclysmic variable. Our result shows that there still exist bright quasars to be discovered. However, at the same time, we conclude that finding new bright quasars in high Galactic latitude regions is very challenging and that the existing compilation of optically bright quasars is nearly complete in the northern hemisphere.