Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High Spatial Resolution Galactic 3D Extinction Mapping with IPHAS   We present an algorithm ({\scshape mead}, for `Mapping Extinction Against
Distance') which will determine intrinsic ($r' - i'$) colour, extinction, and
distance for early-A to K4 stars extracted from the IPHAS $r'/i'/\Halpha$
photometric database. These data can be binned up to map extinction in three
dimensions across the northern Galactic Plane. The large size of the IPHAS
database ($\sim 200$ million unique objects), the accuracy of the digital
photometry it contains and its faint limiting magnitude ($r' \sim 20$) allow
extinction to be mapped with fine angular ($ \sim 10 $ arcmin) and distance
($\sim 0.1$ ~kpc) resolution to distances of up to 10 kpc, outside the Solar
Circle. High reddening within the Solar Circle on occasion brings this range
down to $\sim 2$ kpc. The resolution achieved, both in angle and depth, greatly
exceeds that of previous empirical 3D extinction maps, enabling the structure
of the Galactic Plane to be studied in increased detail. {\scshape mead}
accounts for the effect of the survey magnitude limits, photometric errors,
unresolved ISM substructure, and binarity. The impact of metallicity
variations, within the range typical of the Galactic disc is small. The
accuracy and reliability of {\scshape mead} are tested through the use of
simulated photometry created with Monte-Carlo sampling techniques. The success
of this algorithm is demonstrated on a selection of fields and the results are
compared to the literature.

12
The categories of this paper are: nucl-th
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
2
The categories of this paper are: math