Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A new Measurement of Thermal Conductivity of Iron at high pressures and
  temperatures   Thermal conductivity of the most abundant element in the planetary core, Iron
(Fe) is measured up to Earth's outer core pressure $\sim 120$ GPa. The
measurements are carried out using the laser heated diamond anvil cell
facility, where the absorbed power by Fe metal foil is calculated using
thermodynamical equation. The thermal conductivity of $\gamma-Fe$ linearly
increases up to a maximum experimental pressure 40 GPa. Thermal conductivity of
$\epsilon-Fe$ measured by us shows a saturated value $\sim$ 52 ($\pm$ 5)
$Wm^{-1}K^{-1}$ in the pressure range 77 - 120 GPa. At different pressures
temperature dependence of thermal conductivity show a sharp drop during
melting, which indicates the formation of liquid layer resulting in a thermal
buffer to the heat conduction.

2
The categories of this paper are: math
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph