Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: VLT/UVES constraints on the carbon isotope ratio 12C/13C at z=1.15
  toward the quasar HE 0515-4414   We analyzed the CI lines associated with the damped Ly-alpha system observed
at zabs = 1.15 in the spectrum of HE 0515-4414 to derive the 12C/13C ratio. The
spectrum was obtained by means of the UV-Visual Echelle Spectrograph (UVES) at
the ESO Very Large Telescope (VLT). The obtained lower limit 12C/13C > 80
(2sigma C.L.) shows for the first time that the abundance of 13C in the
extragalactic intervening clouds is very low. This rules out a significant
contribution from intermediate-mass stars to the chemical evolution of matter
sampled by this line of sight. The estimated low amount of 13C is in agreement
with low abundances of nitrogen observed in damped Ly-alpha systems - the
element produced in the same nuclear cycles and from about the same stars as
13C.

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The categories of this paper are: hep-ex
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
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The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph