Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Mass-Dependence of Angular Momentum Evolution in Sun-Like Stars   To better understand the observed distributions of rotation rate and magnetic
activity of sun-like and low-mass stars, we derive a physically motivated
scaling for the dependence of the stellar-wind torque on Rossby number. The
torque also contains an empirically-derived scaling with stellar mass (and
radius), which provides new insight into the mass-dependence of stellar
magnetic and wind properties. We demonstrate that this new formulation explains
why the lowest mass stars are observed to maintain rapid rotation for much
longer than solar-mass stars, and simultaneously, why older populations exhibit
a sequence of slowly rotating stars, in which the low-mass stars rotate more
slowly than solar-mass stars. The model also reproduces some previously
unexplained features in the period-mass diagram for the Kepler field, notably:
the particular shape of the "upper envelope" of the distribution, suggesting
that ~95% of Kepler field stars with measured rotation periods are younger than
~4 Gyr; and the shape of the "lower envelope," corresponding to the location
where stars transition between magnetically saturated and unsaturated regimes.

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The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
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The categories of this paper are: cmp-lg
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
7
The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
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The categories of this paper are: q-alg
9
The categories of this paper are: nlin