Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Towards A Removal of Temperature Dependencies from Abundance
  Determinations   The metal content of a galaxy is a key property for distinguishing between
viable galaxy evolutionary scenarios, and it strongly influences many of the
physical processes in the interstellar medium. An absolute and robust
determination of extragalactic metallicities is essential in constraining
models of chemical enrichment and chemical evolution, however, current gas
phase abundance determinations from optical fine-structure lines are uncertain
to 0.8 dex as conversion of these optical line fluxes to abundances is strongly
dependent on the electron temperature of the ionized gas. In contrast, the
far-IR emission lines can be used to derive an O++ abundance that is relatively
insensitive to temperature, while the ratio of the optical to far-IR lines
provides a consistent temperature to be used in the derivation of an O$^+$
abundance. We present observations of the [O III] 88 \micron\ fine-structure
line in NGC 628 that were obtained as part of the KINGFISH program. These data
are combined with optical IFU data to derive oxygen abundances for seven HII
regions. We find the abundance of these regions to all lie between the high and
low values of strong line calibrations and in agreement with estimates that
assume temperature fluctuations are present in the HII regions.

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The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
17
The categories of this paper are: q-fin
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
29
The categories of this paper are: funct-an
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
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The categories of this paper are: hep-th
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The categories of this paper are: stat
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The categories of this paper are: nucl-ex
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con