Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Propagation and attenuation of pulses driven by low velocity normal
  impacts in granular media   We carry out experiments of low velocity normal impacts into granular
materials that fill an approximately cylindrical 11 gallon tub. Motions in the
granular medium are tracked with an array of 7 embedded accelerometers.
Longitudinal pulses excited by the impact broaden and attenuate as a function
of travel distance from the site of impact. Pulse propagation is not
spherically symmetric about the site of impact. Peak amplitudes are about twice
as large for the pulse propagating downward than at 45 degrees from vertical.
An advection-diffusion model is used to estimate the dependence of pulse
properties as a function of travel distance from the site of impact. The power
law forms for pulse peak pressure, velocity and seismic energy depend on
distance from impact to a power of -2.5 and this rapid decay is approximately
consistent with our experimental measurements. Our experiments support a
seismic jolt model, giving rapid attenuation of impact generated seismic energy
into rubble asteroids, rather than a reverberation model, where seismic energy
slowly decays. We apply our diffusive model to estimate physical properties of
the seismic pulse that will be excited by the forthcoming DART mission impact
onto the secondary, Dimorphos, of the asteroid binary (65803) Didymos system.
We estimate that the pulse peak acceleration will exceed the surface gravity as
it travels through the asteroid.

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The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
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The categories of this paper are: solv-int
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
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The categories of this paper are: comp-gas
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The categories of this paper are: acc-phys
2
The categories of this paper are: math
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The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
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The categories of this paper are: supr-con
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The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio