193 research outputs found
Symposium: Pandemics and the Constitution: Federalism and Contagion: Reevaluating the Role of the CDC
The United States Government’s response to the coronavirus outbreak raises difficult questions of federalism. This essay argues for greater federal leadership and involvement to mount the most effective response to a pandemic. As history shows, a response led by local governments is vulnerable to collective action problems and political impediments. An improved response structure in a contagious disease event would include more federal leadership and policy dictated by the Centers for Disease Control (CDC), to be then effectuated by state and local governments. This power can be exercised either formally, through federal grants, or informally through the influence of public locally-focused CDC recommendations.
Second, this essay argues for greater federal influence over public health measures such as quarantine and isolation for a more uniform national response. As the law now exists, federal authority over everything but international border quarantines is somewhat ambiguous. State and local governments have exercised quarantine authority inconsistently, and may not possess the institutional knowledge to weigh the costs and benefits of confinement actions. Inevitably during a severe pandemic, localities may also push the limits of their authority to quarantine, potentially in opposition to federal government policy, hindering a nationwide pandemic response. Implicit in this recommendation is a call for greater statutory authorization for the CDC.
Finally, the potential constitutional questions that arise from the suggested policy alterations are considered. Government officials are always in a challenging position when responding to a pandemic. This challenge is magnified when federal authority over the matter is unclear. The United States system of public health federalism must be rebalanced in some areas, to gain an effective uniform response to an outbreak of disease
Quadrupole Anisotropy in Dihadron Azimuthal Correlations in Central Au Collisions at =200 GeV
The PHENIX collaboration at the Relativistic Heavy Ion Collider (RHIC)
reports measurements of azimuthal dihadron correlations near midrapidity in
Au collisions at =200 GeV. These measurements
complement recent analyses by experiments at the Large Hadron Collider (LHC)
involving central Pb collisions at =5.02 TeV, which
have indicated strong anisotropic long-range correlations in angular
distributions of hadron pairs. The origin of these anisotropies is currently
unknown. Various competing explanations include parton saturation and
hydrodynamic flow. We observe qualitatively similar, but larger, anisotropies
in Au collisions compared to those seen in Pb collisions at the
LHC. The larger extracted values in Au collisions at RHIC are
consistent with expectations from hydrodynamic calculations owing to the larger
expected initial-state eccentricity compared with that from Pb
collisions. When both are divided by an estimate of the initial-state
eccentricity the scaled anisotropies follow a common trend with multiplicity
that may extend to heavy ion data at RHIC and the LHC, where the anisotropies
are widely thought to arise from hydrodynamic flow.Comment: 375 authors, 7 pages, 5 figures. Published in Phys. Rev. Lett. v2 has
minor changes to text and figures in response to PRL referee suggestions.
Plain text data tables for the points plotted in figures for this and
previous PHENIX publications are (or will be) publicly available at
http://www.phenix.bnl.gov/papers.htm
meson production in Au collisions at GeV
The PHENIX experiment has measured meson production in Au
collisions at GeV using the dimuon and dielectron decay
channels. The meson is measured in the forward (backward) -going
(Au-going) direction, () in the transverse-momentum
() range from 1--7 GeV/, and at midrapidity in the
range below 7 GeV/. The meson invariant yields and
nuclear-modification factors as a function of , rapidity, and centrality
are reported. An enhancement of meson production is observed in the
Au-going direction, while suppression is seen in the -going direction, and
no modification is observed at midrapidity relative to the yield in
collisions scaled by the number of binary collisions. Similar behavior was
previously observed for inclusive charged hadrons and open heavy flavor
indicating similar cold-nuclear-matter effects.Comment: 484 authors, 16 pages, 12 figures, 6 tables. v1 is the version
accepted for publication in Phys. Rev. C. Data tables for the points plotted
in the figures are given in the paper itsel
Centrality categorization for R_{p(d)+A} in high-energy collisions
High-energy proton- and deuteron-nucleus collisions provide an excellent tool
for studying a wide array of physics effects, including modifications of parton
distribution functions in nuclei, gluon saturation, and color neutralization
and hadronization in a nuclear environment, among others. All of these effects
are expected to have a significant dependence on the size of the nuclear target
and the impact parameter of the collision, also known as the collision
centrality. In this article, we detail a method for determining centrality
classes in p(d)+A collisions via cuts on the multiplicity at backward rapidity
(i.e., the nucleus-going direction) and for determining systematic
uncertainties in this procedure. For d+Au collisions at sqrt(s_NN) = 200 GeV we
find that the connection to geometry is confirmed by measuring the fraction of
events in which a neutron from the deuteron does not interact with the nucleus.
As an application, we consider the nuclear modification factors R_{p(d)+A}, for
which there is a potential bias in the measured centrality dependent yields due
to auto-correlations between the process of interest and the backward rapidity
multiplicity. We determine the bias correction factor within this framework.
This method is further tested using the HIJING Monte Carlo generator. We find
that for d+Au collisions at sqrt(s_NN)=200 GeV, these bias corrections are
small and vary by less than 5% (10%) up to p_T = 10 (20) GeV. In contrast, for
p+Pb collisions at sqrt(s_NN) = 5.02 TeV we find these bias factors are an
order of magnitude larger and strongly p_T dependent, likely due to the larger
effect of multi-parton interactions.Comment: 375 authors, 18 pages, 16 figures, 4 tables. Submitted to Phys. Rev.
C. Plain text data tables for the points plotted in figures for this and
previous PHENIX publications are (or will be) publicly available at
http://www.phenix.bnl.gov/papers.htm
L\'evy-stable two-pion Bose-Einstein correlations in GeV AuAu collisions
We present a detailed measurement of charged two-pion correlation functions
in 0%-30% centrality GeV AuAu collisions by the
PHENIX experiment at the Relativistic Heavy Ion Collider. The data are well
described by Bose-Einstein correlation functions stemming from L\'evy-stable
source distributions. Using a fine transverse momentum binning, we extract the
correlation strength parameter , the L\'evy index of stability
and the L\'evy length scale parameter as a function of average
transverse mass of the pair . We find that the positively and the
negatively charged pion pairs yield consistent results, and their correlation
functions are represented, within uncertainties, by the same L\'evy-stable
source functions. The measurements indicate a decrease of the
strength of the correlations at low . The L\'evy length scale parameter
decreases with increasing , following a hydrodynamically
predicted type of scaling behavior. The values of the L\'evy index of stability
are found to be significantly lower than the Gaussian case of
, but also significantly larger than the conjectured value that may
characterize the critical point of a second-order quark-hadron phase
transition.Comment: 448 authors, 25 pages, 11 figures, 4 tables, 2010 data. v2 is version
accepted for publication in Phys. Rev. C. Plain text data tables for the
points plotted in figures for this and previous PHENIX publications are (or
will be) publicly available at http://www.phenix.bnl.gov/papers.htm
Cross Section and Transverse Single-Spin Asymmetry of Mesons in Collisions at GeV at Forward Rapidity
We present a measurement of the cross section and transverse single-spin
asymmetry () for mesons at large pseudorapidity from
~GeV collisions. The measured cross section for
~GeV/ and is well described by a
next-to-leading-order perturbative-quantum-chromodynamics calculation. The
asymmetries have been measured as a function of Feynman- () from
, as well as transverse momentum () from
~GeV/. The asymmetry averaged over positive is
. The results are consistent with prior
transverse single-spin measurements of forward and mesons at
various energies in overlapping ranges. Comparison of different particle
species can help to determine the origin of the large observed asymmetries in
collisions.Comment: 484 authors, 13 pages, 11 figures, 4 tables, 2008 data. v2 is version
accepted by Phys. Rev. D. Plain text data tables for the points plotted in
figures for this and previous PHENIX publications are (or will be)publicly
available at http://www.phenix.bnl.gov/papers.htm
Cross section for production via dielectrons in dAu collisions at GeV
We report a measurement of pairs from semileptonic heavy-flavor
decays in Au collisions at GeV. Exploring the mass
and transverse-momentum dependence of the yield, the bottom decay contribution
can be isolated from charm, and quantified by comparison to {\sc pythia} and
{\sc mc@nlo} simulations. The resulting -production cross section is
~mb, which is equivalent to a nucleon-nucleon cross section of
b.Comment: 375 authors, 16 pages, 8 figures, 7 tables, 2008 data. Submitted to
Phys. Rev. C Plain text data tables for the points plotted in figures for
this and previous PHENIX publications are (or will be) publicly available at
http://www.phenix.bnl.gov/papers.htm
- …