Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Absolute absorption on rubidium D1 line: including resonant
  dipole-dipole interactions   Here we report on measurements of the absolute absorption spectra of dense
rubidium vapour on the D1 line in the weak-probe regime for temperatures up to
170 C and number densities up to 3 \times 10^14 cm^-3. In such vapours,
modifications to the homogeneous linewidth of optical transitions arise due to
dipole-dipole interactions between identical atoms, in superpositions of the
ground and excited states. Absolute absorption spectra were recorded with
deviation of 0.1% between experiment and a theory incorporating resonant
dipole-dipole interactions. The manifestation of dipole-dipole interactions is
a self-broadening contribution to the homogeneous linewidth, which grows
linearly with number density of atoms. Analysis of the absolute absorption
spectra allow us to ascertain the value of the self-broadening coefficient for
the rubidium D1 line: \beta/2\pi = (0.69 \pm 0.04) \times 10^-7 Hz cm^3, in
excellent agreement with the theoretical prediction.

20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
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The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat