Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic field generation in first order phase transition bubble
  collisions   We consider the formation of a ring-like magnetic field in collisions of
bubbles of broken phase in an abelian Higgs model. Particular attention is paid
on multiple collisions. The small collision velocity limit, appropriate to the
electroweak phase transition, is discussed. We argue that after the completion
of the electroweak phase transition, when averaged over nucleation center
distances, there exists a mean magnetic field $B\simeq 2.0\times 10^{20}$ G
with a coherence length $9.1 \times 10^3 GeV^{-1}$ (for m_H=68 GeV). Because of
the ring-like nature of B, the volume average behaves as $B \sim 1/L$. Taking
into account the turbulent enhancement of the field by inverse cascade, we
estimate that colliding electroweak bubbles would give rise to a mean field
$B_{rms}\simeq 10^{-21}$ G at 10 Mpc comoving scale today.

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The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs