1 Introduction

The search for bright quasars ($B \leq 17.0$) has ever been a challenge for all surveys because of their low surface density. On a typical Schmidt field of 25 deg² about 5 bright quasars are expected to be found (Hewett et al. 1995; Köhler et al. 1997) among $30{-}90\,000$ other objects, thus demanding a large coverage of the sky with plates and an efficient selection technique to find a sizeable fraction of such QSOs. The Hamburg Quasar Survey (HQS, Hagen et al. 1995; hereafter Paper I) covers $\approx 13\,600$ deg² of the northern sky ($\delta \gt 0\hbox{$^\circ$}$) at galactic latitudes $\mid b \mid \gt 20\hbox{$^\circ$}$ with digitized objective prism plates, allowing a comprehensive search for these QSOs. On the base of the above mentioned surface densities and taking into account galactic absorption, roughly QSOs are expected in this area, while the most recent QSO catalogue (Véron-Cetty & Véron 1996) lists about 500 QSOs with $B \leq 17.0$ in the same area.

At an even brighter level ($V \approx 16$) the Palomar-Green-Survey (Green et al. 1986; Schmidt & Green 1983) has already discovered the vast majority of QSOs in the HQS area, although no attempt has been made yet to verify its completeness since then (but see Goldschmidt et al. 1992; Savage et al. 1993; Köhler et al. 1997). This survey was restricted to redshifts $z \leq 2.2$ due to its selection technique, leaving the surface density of high-redshift z > 2.2 QSOs at $B \leq 17.0$unsettled (see Hartwick & Schade 1990). An extrapolation from fainter levels to $B \leq 17.0$ predicts a number of the order of 10² QSOs in the HQS area, while the Véron-Cetty & Véron catalogue lists 34 so far - including 4 HQS QSOs already published.

Summarizing we expect to at least double the number of bright z$\ge$2 QSOs in the survey area. The bright high-redshift QSOs from the Hamburg Quasar Survey published so far (Reimers et al. 1989; Hagen et al. 1992; Reimers et al. 1995) have been the source of considerable progress in our understanding of the intergalactic medium via high-resolution, high S/N optical spectra (metal lines: Tripp et al. 1996, 1997; Ly$\alpha$ forest: Kirkman & Tytler 1997) and by means of UV spectra using HST (HeI: Reimers & Vogel 1993; UV high ionization resonance lines: Reimers et al. 1992; Vogel & Reimers 1995) or the Hopkins Ultraviolet Tetelescope (HUT) (HeII: Davidsen et al. 1996).

In this paper we present a further list of bright, spectroscopically verified QSOs. While this list is not a complete sample, we briefly estimate the potential completeness of our survey. Details on the Schmidt observations and the digitization method were described in Paper I. A first list of QSOs found during the development phase of the search technic was published in Engels et al. (1998).