Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Moduli spaces of framed sheaves on certain ruled surfaces over elliptic
  curves   Fix a ruled surface S obtained as the projective completion of a line bundle
L on a complex elliptic curve; we study the moduli problem of parametrizing
certain pairs consisting of a sheaf E on S and a map of E to a fixed reference
sheaf on S. We prove that the full moduli stack for this problem is
representable by a scheme in some cases. Moreover, the moduli stack admits an
action by the group ${\mathbf C}^*$, and we determine its fixed-point set,
which leads in some special cases to explicit formulas for the rational
homology of the moduli space.

17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex