Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An Artificial Neural Network Approach to Classification of Galaxy
  Spectra   We present a method for automated classification of galaxies with low
signal-to-noise (S/N) spectra typical of redshift surveys. We develop spectral
simulations based on the parameters for the 2dF Galaxy Redshift Survey, and
with these simulations we investigate the technique of Principal Component
Analysis when applied specifically to spectra of low S/N. We relate the
objective principal components to features in the spectra and use a small
number of components to successfully reconstruct the underlying signal from the
low quality spectra. Using the principal components as input, we train an
Artificial Neural Network to classify the noisy simulated spectra into
morphological classes, revealing the success of the classification against the
observed $b_{\rm J}$ magnitude of the source, which we compare with alternative
methods of classification. We find that more than 90\% of our sample of normal
galaxies are correctly classified into one of five broad morphological classes
for simulations at $b_{\rm J}$=19.7. By dividing the data into separate sets we
show that a classification onto the Hubble sequence is only relevant for normal
galaxies and that spectra with unusual features should be incorporated into a
classification scheme based predominantly on their spectral signatures. We
discuss how an Artificial Neural Network can be used to distinguish normal and
unusual galaxy spectra, and discuss the possible application of these results
to spectra from galaxy redshift surveys.

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The categories of this paper are: funct-an
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The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
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The categories of this paper are: solv-int
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The categories of this paper are: econ
19
The categories of this paper are: eess
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The categories of this paper are: supr-con
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The categories of this paper are: adap-org
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The categories of this paper are: q-alg
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The categories of this paper are: hep-ex
1
The categories of this paper are: cs
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The categories of this paper are: nucl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
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The categories of this paper are: ao-sci