Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Centimeter-band Variability in GPS Sources   Monitoring results are presented for the Stangellini 1 Jy GHz-peaked-spectrum
source sample, illustrating that several members exhibit variability in total
flux and/or linear polarization over timescales of order a decade. The
variability occurs while the spectrum, based on the integrated fluxes, remains
steep and characteristic of a transparent source. Total flux variability is
unexpected in view of recent VLBI observations indicating no or hidden cores in
several members. However, both the variability, and the detection of circular
polarization in one class member, argue for the presence of opacity in some
portion of the radio jet.

21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci