Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: GALEX Observations of "Passive Spirals" in the Cluster Cl 0024+17: Clues
  to the Formation of S0 Galaxies   We present new results from deep GALEX UV imaging of the cluster Cl 0024+17
at z~0.4. Rest-frame far UV emission is detected from a large fraction of
so-called ``passive spiral galaxies'' -a significant population which exhibits
spiral morphology with little or no spectroscopic evidence for ongoing star
formation. This population is thought to represent infalling galaxies whose
star formation has been somehow truncated by environmental processes, possibly
in morphological transition to S0 galaxies. Compared to normal cluster spirals,
we find that passive spirals are redder in FUV-optical color, while exhibiting
much stronger UV emission than cluster E/S0s - as expected for
recently-truncated star formation. By modeling the different temporal
sensitivities of UV and spectroscopic data to recent activity, we show that
star formation in passive spirals decayed on timescales of less than 1 Gyr,
consistent with `gas starvation' - a process where the cluster environment
prevents cold gas from accreting onto the spiral disk. Intriguingly, the
fraction of spirals currently observed in the passive phase is consistent with
the longer period expected for the morphological transformation and the
subsequent build-up of cluster S0s observed since z=0.4.

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The categories of this paper are: cs
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The categories of this paper are: cond-mat
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The categories of this paper are: nucl-ex
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The categories of this paper are: supr-con
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The categories of this paper are: quant-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: eess
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The categories of this paper are: hep-ex
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The categories of this paper are: math
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The categories of this paper are: math-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: dg-ga
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The categories of this paper are: solv-int
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The categories of this paper are: atom-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: stat