Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: SPI observations of the diffuse 60Fe emission in the Galaxy   Gamma-ray line emission from radioactive decay of 60Fe provides constraints
on nucleosynthesis in massive stars and supernovae. The spectrometer SPI on
board INTEGRAL has accumulated nearly three years of data on gamma-ray emission
from the Galactic plane. We have analyzed these data with suitable
instrumental-background models and sky distributions to produce high-resolution
spectra of Galactic emission. We detect the gamma-ray lines from 60Fe decay at
1173 and 1333 keV, obtaining an improvement over our earlier measurement of
both lines with now 4.9 sigma significance for the combination of the two
lines. The average flux per line is (4.4 \pm 0.9) \times 10^{-5} ph cm^{-2}
s^{-1} rad^{-1} for the inner Galaxy region. Deriving the Galactic 26Al
gamma-ray line flux with using the same set of observations and analysis
method, we determine the flux ratio of 60Fe/26Al gamma-rays as 0.148 \pm 0.06.
The current theoretical predictions are still consistent with our result.

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The categories of this paper are: alg-geom
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th
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The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
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The categories of this paper are: stat
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
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The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
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The categories of this paper are: solv-int
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The categories of this paper are: eess