2,334 research outputs found
Reconsideration of the QCD corrections to the decays into light hadrons using the principle of maximum conformality
In the paper, we analyze the decays into light hadrons at the
next-to-leading order QCD corrections by applying the principle of maximum
conformality (PMC). The relativistic correction at the -order level has been included in the discussion, which gives about
contribution to the ratio . The PMC, which satisfies the renormalization
group invariance, is designed to obtain a scale-fixed and scheme-independent
prediction at any fixed order. To avoid the confusion of treating -terms,
we transform the usual pQCD series into the one under the
minimal momentum space subtraction scheme. To compare with the prediction under
conventional scale setting, , after applying the PMC, we obtain
, where the
errors are squared averages of the ones caused by and . The PMC prediction agrees with the recent PDG value within errors, i.e.
. Thus we think the mismatching
of the prediction under conventional scale-setting with the data is due to
improper choice of scale, which however can be solved by using the PMC.Comment: 5 pages, 2 figure
Entropic uncertainty relations for Markovian and non-Markovian processes under a structured bosonic reservoir
The uncertainty relation is a fundamental limit in quantum mechanics and is
of great importance to quantum information processing as it relates to quantum
precision measurement. Due to interactions with the surrounding environment, a
quantum system will unavoidably suffer from decoherence. Here, we investigate
the dynamic behaviors of the entropic uncertainty relation of an atom-cavity
interacting system under a bosonic reservoir during the crossover between
Markovian and non-Markovian regimes. Specifically, we explore the dynamic
behavior of the entropic uncertainty relation for a pair of incompatible
observables under the reservoir-induced atomic decay effect both with and
without quantum memory. We find that the uncertainty dramatically depends on
both the atom-cavity and the cavity-reservoir interactions, as well as the
correlation time, , of the structured reservoir. Furthermore, we verify
that the uncertainty is anti-correlated with the purity of the state of the
observed qubit-system. We also propose a remarkably simple and efficient way to
reduce the uncertainty by utilizing quantum weak measurement reversal.
Therefore our work offers a new insight into the uncertainty dynamics for
multi-component measurements within an open system, and is thus important for
quantum precision measurements.Comment: 17 pages, 9 figures, to appear in Scientific Report
Loss of soil carbon and nitrogen indicates climate change-induced alterations in a temperate forest ecosystem
Climate warming is expected to influence terrestrial biogeochemical cycles by modifying the quality and quantity of plant litter input to soils. Although a growing number of studies recognize the importance of plant litter input in influencing the loss of soil organic matter (SOM) through a phenomenon called the priming effect (PE), the exact mechanisms behind PE are not well known. Importantly, most PE research is based on short term pot experiments in which fresh organic matter (FOM) input is represented by a single addition of compounds of unnaturally simple chemical composition. Furthermore, only a few studies exist in which the PE was explored in terms of organic C (SOC) and total N content in the soil. Here, we report results of a 3-year long litter manip-ulation study conducted under natural conditions in a broadleaved Korean pine forest in N-E China. We show that the extra supply (twice the normal input) of aboveground tree litter composing of conifer needles, leaves and small twigs was associated not only with slightly decreased SOC (by 5%) but especially that of soil total N (STN) (by 15%) content in the top soil (0-5 cm depth). In contrast, removal of litter resulted in an increased (ca. 15%) amount of both SOC and STN during the study when compared to control soils receiving natural litter input. Despite the enhanced leaf litter decomposition rate in the treatment receiving extra litter, the changes in SOC and STN were related neither to soil microbial biomass nor to community composition. The amount of N lost (40.0 g m- 2) in the soil due to litter addition was ca. three times the amount of N added (12.3 g m- 2) via the litter, while the amount of C lost (238 g m- 2) was about one third of that added (940 g m- 2), suggesting that soil N in our research site is more prone to the PE than soil C. As we did not manipulate belowground FOM input, our results suggest that input of aboveground litter rather than that by roots explained the PE in our study. Results of our long-term study conducted under natural conditions in undisturbed forest soils highlight the large potential of recalcitrant, aboveground litter to affect the PE, which should not go unnoticed when predicting the role of forest soils under conditions (such as climate warming) when these soils act as C sinks.Peer reviewe
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