Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: ESO Imaging Survey: Optical follow-up of 12 selected XMM-Newton fields   (Abridged) This paper presents the data recently released for the
XMM-Newton/WFI survey carried out as part of the ESO Imaging Survey (EIS)
project. The aim of this survey is to provide optical imaging follow-up data in
BVRI for identification of serendipitously detected X-ray sources in selected
XMM-Newton fields. In this paper, fully calibrated individual and stacked
images of 12 fields as well as science-grade catalogs for the 8 fields located
at high-galactic latitude are presented. The data covers an area of \sim 3
square degrees for each of the four passbands. The median limiting magnitudes
(AB system, 2" aperture, 5\sigma detection limit) are 25.20, 24.92, 24.66, and
24.39 mag for B-, V-, R-, and I-band, respectively. These survey products,
together with their logs, are available to the community for science
exploitation in conjunction with their X-ray counterparts. Preliminary results
from the X-ray/optical cross-correlation analysis show that about 61% of the
detected X-ray point sources in deep XMM-Newton exposures have at least one
optical counterpart within 2" radius down to R \simeq 25 mag, 50% of which are
so faint as to require VLT observations thereby meeting one of the top
requirements of the survey, namely to produce large samples for spectroscopic
follow-up with the VLT, whereas only 15% of the objects have counterparts down
to the DSS limiting magnitude.

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The categories of this paper are: supr-con
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The categories of this paper are: stat
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The categories of this paper are: nucl-th
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The categories of this paper are: cs
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The categories of this paper are: hep-th
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The categories of this paper are: mtrl-th
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The categories of this paper are: eess
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The categories of this paper are: dg-ga
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The categories of this paper are: acc-phys
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The categories of this paper are: funct-an
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The categories of this paper are: econ
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The categories of this paper are: math-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: nucl-ex
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The categories of this paper are: chao-dyn
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The categories of this paper are: physics