Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Photoacoustics Modelling using Amplitude Mode Expansion Method in a
  Multiscale T-cell Resonator   The photoacoustic (PA) effect consisting of the generation of an acoustic
signal based on the absorption of light has already demonstrated its potential
for various spectroscopic applications for both gaseous and solid samples. The
signal produced during photoacoustic spectroscopy (PAS) measurement is,
however, usually weak and needs to be amplified. This is achieved by using a
photoacoustic cell resonator where acoustic resonances are utilized to
significantly boost the signal. Therefore, a PA resonator has a significant
role in PAS measurement set-ups. When designing or optimizing a new PA
resonator, numerical methods are generally used to simulate the photoacoustic
signal generation. In this paper, the amplitude mode expansion (AME) method is
presented as a quick and accurate simulation tool. The method is used to
simulate the photoacoustic signal in a multi-scale T-cell resonator over a wide
frequency range. The AME method is based on eigenmode expansion and
introduction of losses by quality factors. The AME simulation results are
compared and analyzed against the results from the viscothermal method.
Reasonably good agreement is obtained between the two methods. However, small
frequency shifts in the resonances of the AME method are noted. The shifts are
attributed to the location of the dominant mode within the T-cell. The
viscothermal method is considered the most accurate method for simulating the
photoacoustic signal in small resonators. However, it is computationally very
demanding. The AME method provides a much faster simulation alternative. This
is particularly useful in the design and optimization of photoacoustic
resonators where numerical methods are preferred over experimental measurements
due to their speed and low cost.

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The categories of this paper are: math
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The categories of this paper are: comp-gas
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The categories of this paper are: gr-qc
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The categories of this paper are: math-ph
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The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
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The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
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The categories of this paper are: nucl-th
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The categories of this paper are: q-fin
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The categories of this paper are: chem-ph
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The categories of this paper are: supr-con
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The categories of this paper are: hep-lat
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ph