Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Detection of Cold Atomic Clouds in the Magellanic Bridge   We report a detection of cold atomic hydrogen in the Magellanic Bridge using
21-cm absorption spectroscopy toward the radio source B0312-770. With a column
density of N_HI=1.2E20 cm^-2, a maximum absorption optical depth of tau=0.10
and a maximum 21-cm emission brightness temperature of 1.4 K, this line of
sight yields a spin temperature, T_s, between 20 K and 40 K. H I 21-cm
absorption and emission spectroscopy toward 7 other low column density
sightlines on the periphery of the LMC and SMC reveal absorption toward one
additional background radio source behind the SMC with tau=0.03. The data have
typical sensitivities of sigma_tau=0.005 to 0.070 in absorption and
sigma_{T_B}=0.03 K in emission. These data demonstrate the presence of a cold
atomic phase which is probably accompanied by molecular condensations in the
tenuous interstellar medium of the Bridge region. Young OB stars observed in
the Magellanic Bridge could form "in situ" from these cold condensations rather
than migrate from regions of active star formation in the main body of the SMC.
The existence of cold condensations and star formation in the Magellanic Bridge
might be understood as a small scale version of the mechanism that produces
star formation in the tidal tails of interacting galaxies.

21
The categories of this paper are: adap-org
4
The categories of this paper are: cond-mat
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
9
The categories of this paper are: nlin
23
The categories of this paper are: solv-int