9,377 research outputs found
On the Budget-Constrained IRS: Equilibrium and Equilibrium and efficiency
This paper extends Graetz, Reinganum and Wildes (1986) seminal work on tax compliance to the real-world scenario where the IRS (Internal Revenue Service) faces a budget constraint imposed upon her by the Congress. The paper consists of two parts. The first part is positive we characterize the equilibria resulting from the interaction between taxpayers and the budget-constrained IRS. The second part is normative - we examine the effeciency implication of varying the size of the budget allocated to the IRS. It is shown that, to mitigate or eliminate the so-called congestion e¤ect, the IRS should be sufficiently budgeted and, in particular, we provide a case for the policy prescription that the size of the budget allocated to the IRS should be expanded as long as an additional dollar allocated could return more than an additional dollar of tax revenue.
Temporal variability in composition and fluxes of Yellow River particulate organic matter
This study examines temporal variations of the abundance and carbon isotopic characteristics of particulate organic carbon (POC) and specific-source compounds in the context of hydrological variability in the Yellow River. The content and bulk carbon isotopic characteristics (13C and 14C) of POC were relatively uniform over the hydrologic (seasonal) cycle. We attribute these temporally invariant geochemical characteristics to the dominant contribution of loess material to the suspended particulate matter (SPM). In contrast, molecular-level signals revealed that hydrologic conditions exert a significant influence on the proportional contributions of petrogenic and especially fresh plant-derived OC, while pre-aged soil OC is mobilized via deeper erosion processes (e.g., gully erosion, mudslides) and is independent of hydrodynamics and surface runoff. A coupled biomarker-isotope mixing model was applied to estimate the time-varying supply of contemporary/modern biomass, pre-aged soil, and fossil OC components to Chinese marginal seas from the Yellow River. We found that natural (e.g., precipitation) and human-induced (e.g., water and sediment regulation) variations in hydrological regime strongly influence the flux with the magnitude of the corresponding annual fluxes of POC ranging between 0.343 ± 0.122 Mt yr−1 and 0.581 ± 0.213 Mt yr−1, but less strongly infleunce proportions of the different OC constituents. Inter-annual differences in pre-aged soil and fossil OC fluxes imply that extreme climate events (e.g., floods) modulate the exhumation and export of old carbon to the ocean, but the OC homogeneity in the pre-aged mineral soil-dominated watersheds facilitates robust predictions in terms of OC transport dynamics in the past (sediment cores) and in the future
The - and -wave fully charmed tetraquark states and their radial excitations
Inspired by recent progresses in observations of the fully charmed tetraquark
states by LHCb, CMS, and ATLAS Collaborations, we perform a systematic study of
the ground states and the first radial excitations of the - and -wave
system. Their mass spectra, root
mean square(r.m.s.) radii and radial density distributions are studied with the
relativized quark model. The calculations show that there is no stable bound
states for the full-charmed tetraquark states, and the r.m.s. radii of these
tetraquark states are smaller than 1 fm. Our results support assigning X(6600)
structure, MeV, as one of the (1) and
(1) states or their mixtures. Another structure also named as
X(6600) by CMS Collaboration, GeV,
may arise from the lowest 1 states with =, , and
. The possible assignments for X(6900) include the (2),
(2) states, and the highest 1 state with . As for
X(7200), it can be interpreted as one of the highest 2 states with
, , and , and the 3 states can not be
completely excluded from the candidates.Comment: to be published in European Physical Journal
Strong decay properties of single heavy baryons , and
Motivated by recent progresses in experiments in searching for the
baryons, we systematically analyze the strong decay behaviors of
single heavy baryons , and . The two-body
strong decay properties of -wave, -wave and some -wave states are
studied with the model. The results support assigning the recently
observed and as the 2S()
and 1D() states, respectively. In addition, the quantum
numbers of many other experimentally observed baryons are also suggested
according to their strong decays. Finally, some baryons which have good
potentials to be observed in experiments are predicted and the possible decay
channels for searching for these predicted states are also suggested.Comment: arXiv admin note: substantial text overlap with arXiv:2206.0812
Systematic analysis of doubly charmed baryons and
In this work, we perform a systematic study of the mass spectra, the root
mean square(r.m.s.) radii and the radial density distributions of the doubly
charmed baryons and . The calculations are carried out
in the frame work of Godfrey-Isgur (GI) relativized quark model, where the
baryon is regarded as a real three-body system of quarks. Our results show that
the excited energy of doubly charmed baryon with -mode is lower than
those of the -mode and - mixing mode, which indicates
that the lowest state is dominated by the -mode. According to this
conclusion, we systematically investigate the mass spectra, the r.m.s. radii of
the ground and excited states(, , ,
and ) with -mode. Using the wave functions obtained from quark
model, we also study the radial density distributions. Finally, with the
predicated mass spectra, the Regge trajectories of and
in the (,) plane are constructed, and the slopes, intercepts are
determined by linear fitting. It is found that model predicted masses fit
nicely to the constructed Regge trajectories.Comment: arXiv admin note: text overlap with arXiv:2206.0812
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