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A Time Evolution Study of the Superhumps of the Dwarf Nova 1RXS J232953.9+062814 by Wavelet Transform
The time evolution behaviour of the superhumps of the dwarf nova 1RXS
J232953.9+062814 is investigated with the wavelet analysis method. On the basis
of two nights CCD photometry performed during its first superoutburst as well
as other published brightness data, we reveal the superhump's time-dependence
as a function of periods and time. Our light curves, which phased in the rapid
decay ending portion of the superoutburst and in the dawn of a following normal
outburst, are important to help trace the superhump evolution for the star.
Evident amplitude variations of the superhumps, reflecting the fading of
outbursts, are detected. The general profile of brightness fading over the
outbursts roughly followed an exponential decay law or a form of a five-order
polynomial. Both the superhump period and the orbital period of the binary
system are detected in the present data. We obtain P_sh=0.04575(5) d and
P_orb=0.04496(5) d. They agree with the existing values based on additional
data. The two periods exchanged their roles during the superhump evolution.Comment: 7 pages, 9 figures, submitted to Astronomy & Astrophysic
Is the meson a dynamically generated resonance? -- a lesson learned from the O(N) model and beyond
O(N) linear model is solvable in the large limit and hence
provides a useful theoretical laboratory to test various unitarization
approximations. We find that the large limit and the
limit do not commute. In order to get the correct large spectrum one has
to firstly take the large limit. We argue that the meson may
not be described as generated dynamically. On the contrary, it is most
appropriately described at the same level as the pions, i.e, both appear
explicitly in the effective lagrangian. Actually it is very likely the
meson responsible for the spontaneous chiral symmetry breaking in a lagrangian
with linearly realized chiral symmetry.Comment: 15 pages, 3 figurs; references added; discussions slightly modified;
revised version accepted by IJMP
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