Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The mass function of the Las Campanas loose groups of galaxies   We have determined the mass function of loose groups of galaxies in the Las
Campanas Redshift Survey. Loose groups of galaxies in the LCRS range in mass
from $M \sim 10^{12} {\rm M}_{\sun}$ to $10^{15} {\rm M}_{\sun}$. We find that
the sample is almost complete for masses in the interval $5\cdot 10^{13}-8\cdot
10^{14} {\rm M}_{\sun}$. Comparison of the observed mass function with
theoretical mass functions obtained from N-body simulations shows good
agreement with a CDM model with the parameters $\Omega_m = 0.3$,
$\Omega_{\Lambda} = 0.7$ and the amplitude of perturbations about
$\sigma_8=0.78-0.87$. For smaller masses the mass function of LCRS loose groups
flattens out, differing considerably from the group mass function found by
Girardi and Giuricin (2000) and from mass functions obtained by numerical
simulations.

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The categories of this paper are: atom-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: gr-qc
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The categories of this paper are: q-bio
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The categories of this paper are: funct-an
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-ex
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The categories of this paper are: chao-dyn
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The categories of this paper are: physics
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The categories of this paper are: alg-geom
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The categories of this paper are: adap-org
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The categories of this paper are: cmp-lg
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The categories of this paper are: stat
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The categories of this paper are: mtrl-th
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The categories of this paper are: supr-con