5,822 research outputs found
Tracking ocean heat uptake during the surface warming hiatus.
Ocean heat uptake is observed to penetrate deep into the Atlantic and Southern Oceans during the recent hiatus of global warming. Here we show that the deep heat penetration in these two basins is not unique to the hiatus but is characteristic of anthropogenic warming and merely reflects the depth of the mean meridional overturning circulation in the basin. We find, however, that heat redistribution in the upper 350 m between the Pacific and Indian Oceans is closely tied to the surface warming hiatus. The Indian Ocean shows an anomalous warming below 50 m during hiatus events due to an enhanced heat transport by the Indonesian throughflow in response to the intensified trade winds in the equatorial Pacific. Thus, the Pacific and Indian Oceans are the key regions to track ocean heat uptake during the surface warming hiatus
Lattice study on and X(3872)
Properties of charmonium are investigated in quenched
lattice QCD. The mass of is determined to be 3.80(3) GeV, which is
close to the mass of -wave charmonium and in agreement with
quark model predictions. The transition width of
is also obtained with a value keV. Since the possible
assignment to X(3872) has not been ruled out by experiments, our results help
to clarify the nature of X(3872).Comment: 15 pages, 8 figures. typos, grammatical errors and some references
corrected, redundant discussions deleted, conclusion does not change.
published versio
Investigating the topological structure of quenched lattice QCD with overlap fermions by using multi-probing approximation
The topological charge density and topological susceptibility are determined
by multi-probing approximation using overlap fermions in quenched SU(3) gauge
theory. Then we investigate the topological structure of the quenched QCD
vacuum, and compare it with results from the all-scale topological density, the
results are consistent. Random permuted topological charge density is used to
check whether these structures represent underlying ordered properties.
Pseudoscalar glueball mass is extracted from the two-point correlation function
of the topological charge density. We study ensembles of different lattice
spacing with the same lattice volume , the results are
compatible with the results of all-scale topological charge density, and the
topological structures revealed by multi-probing are much closer to all-scale
topological charge density than that by eigenmode expansion.Comment: 12 pages,34 figure
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