Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Differentiating sharp phase transitions from mixed states in neutron
  stars   The internal composition of neutron stars is still an open issue in
astrophysics. Their innermost regions are impervious to light propagation and
gravitational waves mostly carry global aspects of stars, meaning that only
indirect inferences of their interiors could be obtained. Here we estimate the
observational accuracy and discuss ways to differentiate a mixed phase/state
from a sharp phase transition region in a hybrid star by means of some
electromagnetic and gravitational wave observables. We show that different
transition constructions lead to similar sequences of stellar configurations
due to their shared thermodynamic properties. In the most optimistic case - a
strong quark-hadron density jump phase transition - radius and mass
observations require fractional uncertainties smaller than $1-2\%$ to
differentiate mixed states from sharp phase transitions. For tidal
deformations, relative uncertainties should be smaller than $5-10\%$. However,
for masses around the onset of stable quark cores, relative tidal deformation
changes associated with strong sharp phase transitions and mixed states
connecting the two pure phases could be much larger (up to around $20-30\%$).
If one compares purely hadronic stars (masses below their phase transition
thresholds) with those having mixed states, relative tidal deformation and
radius differences might be even more pronounced (roughly up to $50\%$ and
$5\%$, respectively). All the above suggests that 2.5- and 3rd generation
gravitational wave detectors and near-term electromagnetic missions may be able
to start assessing some aspects of phase transitions in neutron stars. Finally,
we briefly discuss other observables that may also be relevant for such probes.

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The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
2
The categories of this paper are: math
18
The categories of this paper are: econ
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
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The categories of this paper are: cond-mat
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The categories of this paper are: q-bio
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The categories of this paper are: hep-lat
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: cs
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The categories of this paper are: patt-sol