10,105 research outputs found
The Happer's puzzle degeneracies and Yangian
We find operators distinguishing the degenerate states for the Hamiltonian
at that was given by Happer
et al to interpret the curious degeneracies of the Zeeman effect for
condensed vapor of Rb. The operators obey Yangian commutation relations.
We show that the curious degeneracies seem to verify the Yangian algebraic
structure for quantum tensor space and are consistent with the representation
theory of .Comment: 8 pages, Latex fil
Low Redshift QSO Lyman alpha Absorption Line Systems Associated with Galaxies
In this paper we present Monte-Carlo simulations of Lyman alpha absorption
systems which originate in galactic haloes, galaxy discs and dark matter (DM)
satellites around big central haloes. It is found that for strong Lyman alpha
absorption lines galactic haloes and satellites can explain ~20% and 40% of the
line number density of QSO absorption line key project respectively. If big
galaxies indeed possess such large numbers of DM satellites and they possess
gas, these satellites may play an important role for strong Lyman alpha lines.
However the predicted number density of Lyman-limit systems by satellites is
\~0.1 (per unit redshift), which is four times smaller than that by halo
clouds. Including galactic haloes, satellites and HI discs of spirals, the
predicted number density of strong lines can be as much as 60% of the HST
result. The models can also predict all of the observed Lyman-limit systems.
The average covering factor within 250 kpc/h is estimated to be ~0.36. And the
effective absorption radius of a galaxy is estimated to be ~150 kpc/h. The
models predict W_r propto rho^{-0.5} L_B^{0.15} (1+z)^{-0.5}. We study the
selection effects of selection criteria similar to the imaging and
spectroscopic surveys. We simulate mock observations through known QSO
lines-of-sight and find that selection effects can statistically tighten the
dependence of line width on projected distance. (abridged)Comment: 23 pages, 9 postscript figures; references updated, minor change in
section
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