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The exchange of the polycation, poly- l -lysine (PLL), within polymeric multi-layer films constructed with anionic poly(N-isopropylacrylamide)–co-acrylic acid (pNIPAm-co-AAc) microgels was explored. Via incorporation of a fluorescent tag on PLL, the incorporation and distribution of PLL was visualized by fluorescence microscopy and optical extinction techniques. Using UV-vis spectrophotometry, the absorbance of PLL during multi-layer film formation was monitored. Distinctive “in” and “out” diffusive properties of the polycation with limited exchange was observed. Additionally, mechanical deformation was used to probe the influence of self-healing on PLL redistribution across an entire multi-layer film depth; CLSM was utilized to compare the fluorescence profile of these films before and after healing, and a lack of polycation exchange throughout the entire microgel-polyelectrolyte film depth was revealed. Importantly, these results stand in contrast to those observed previously in purely linear polyelectrolyte films, which suggests polycation-microgel interactions that are somewhat unique as compared to the interactions observed for purely linear polyelectrolyte complexation.

ParaView is a high performance visualization application not widely used in High Energy Physics (HEP). It is a long standing open source project led by Kitware and involves several Department of Energy (DOE) and Department of Defense (DOD) laboratories. Futhermore, it has been adopted by many DOE supercomputing centers and other sites. ParaView is unique in speed and efficiency by using state-of-the-art techniques developed by the academic visualization community that are often not found in applications written by the HEP community. In-situ visualization of events, where event details are visualized during processing/analysis, is a common task for experiment software frameworks. Kitware supplies Catalyst, a library that enables scientific software to serve visualization objects to client ParaView viewers yielding a real-time event display. Connecting ParaView to the Fermilab art framework will be described and the capabilities it brings discussed.

This paper presents the beam dynamics systematic corrections and their uncertainties for the Run-1 dataset of the Fermilab Muong−2Experiment. Two corrections to the measured muon precession frequencyωamare associated with well-known effects owing to the use of electrostatic quadrupole (ESQ) vertical focusing in the storage ring. An average vertically oriented motional magnetic field is felt by relativistic muons passing transversely through the radial electric field components created by the ESQ system. The correction depends on the stored momentum distribution and the tunes of the ring, which has relatively weak vertical focusing. Vertical betatron motions imply that the muons do not orbit the ring in a plane exactly orthogonal to the vertical magnetic field direction. A correction is necessary to account for an average pitch angle associated with their trajectories. A third small correction is necessary, because muons that escape the ring during the storage time are slightly biased in initial spin phase compared to the parent distribution. Finally, because two high-voltage resistors in the ESQ network had longer than designedRCtime constants, the vertical and horizontal centroids and envelopes of the stored muon beam drifted slightly, but coherently, during each storage ring fill. This led to the discovery of an important phase-acceptance relationship that requires a correction. The sum of the corrections toωamis0.50±0.09ppm; the uncertainty is small compared to the 0.43 ppm statistical precision ofωam.

We study ionic microgel suspensions composed of swollen particles for various single-particle stiffnesses. We measure the osmotic pressure \\(\\pi\\) of these suspensions and show that it is dominated by the contribution of free ions in solution. As this ionic osmotic pressure depends on the volume fraction of the suspension \\(\\phi\\), we can determine \\(\\phi\\) from \\(\\pi\\), even at volume fractions so high that the microgel particles are compressed. We find that the width of the fluid-solid phase coexistence, measured using \\(\\phi\\), is larger than its hard-sphere value for the stiffer microgels that we study and progressively decreases for softer microgels. For sufficiently soft microgels, the suspensions are fluid-like, irrespective of volume fraction. By calculating the dependence on \\(\\phi\\) of the mean volume of a microgel particle, we show that the behavior of the phase-coexistence width correlates with whether or not the microgel particles are compressed at the volume fractions corresponding to fluid-solid coexistence.

Communal roosting is often a regional phenomenon that involves wide-ranging and long-lasting relationships among associations. We examined roosting behavior on a scale sufficiently large to detect regional and seasonal patterns. For five roosting seasons (June-November), we studied the population dynamics of all roosting flocks of European Starlings (Sturnus vulgaris) and Common Grackles (Quiscalus quiscula) located within a 1,000-km2census area in central New Jersey. Roosts were active from 3-20 weeks and ranged in size from 2,000 to over 100,000 individuals. The total roosting population (TRP) in \"major\" (>2,000 birds) flocks increased through early summer, generally achieving maximum size in mid-August when the largest number of roosts was active. When TRP was largest, size of major roosts varied greatly (range 2,000-100,000 individuals). Through late summer and early fall, size and number of major roosts and TRP declined. By late fall few major roosts were active, but those remaining were large (>30,000). Movements of individual birds (radio-tagged) suggested that changes in size of TRP resulted largely from exchange of the local population between small, \"minor\" roosts (largely undetected and not included in roost censuses) and major flocks. Current hypotheses concerning the functional basis of communal roosting do not adequately explain patterns of roosting behavior that we observed.

We present a new measurement of the positive muon magnetic anomaly, \\(a_\\mu \\equiv (g_\\mu - 2)/2\\), from the Fermilab Muon \\(g\\!-\\!2\\) Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, \\(\\tilde{\\omega}'^{}_p\\), and of the anomalous precession frequency corrected for beam dynamics effects, \\(\\omega_a\\). From the ratio \\(\\omega_a / \\tilde{\\omega}'^{}_p\\), together with precisely determined external parameters, we determine \\(a_\\mu = 116\\,592\\,057(25) \\times 10^{-11}\\) (0.21 ppm). Combining this result with our previous result from the 2018 data, we obtain \\(a_\\mu\\text{(FNAL)} = 116\\,592\\,055(24) \\times 10^{-11}\\) (0.20 ppm). The new experimental world average is \\(a_\\mu (\\text{Exp}) = 116\\,592\\,059(22)\\times 10^{-11}\\) (0.19 ppm), which represents a factor of 2 improvement in precision.

The Fermi National Accelerator Laboratory has measured the anomalous precession frequency \\(a^{}_\\mu = (g^{}_\\mu-2)/2\\) of the muon to a combined precision of 0.46 parts per million with data collected during its first physics run in 2018. This paper documents the measurement of the magnetic field in the muon storage ring. The magnetic field is monitored by nuclear magnetic resonance systems and calibrated in terms of the equivalent proton spin precession frequency in a spherical water sample at 34.7\\(^\\circ\\)C. The measured field is weighted by the muon distribution resulting in \\(\\tilde{\\omega}'^{}_p\\), the denominator in the ratio \\(\\omega^{}_a\\)/\\(\\tilde{\\omega}'^{}_p\\) that together with known fundamental constants yields \\(a^{}_\\mu\\). The reported uncertainty on \\(\\tilde{\\omega}'^{}_p\\) for the Run-1 data set is 114 ppb consisting of uncertainty contributions from frequency extraction, calibration, mapping, tracking, and averaging of 56 ppb, and contributions from fast transient fields of 99 ppb.

This paper presents the beam dynamics systematic corrections and their uncertainties for the Run-1 data set of the Fermilab Muon g-2 Experiment. Two corrections to the measured muon precession frequency \\(\\omega_a^m\\) are associated with well-known effects owing to the use of electrostatic quadrupole (ESQ) vertical focusing in the storage ring. An average vertically oriented motional magnetic field is felt by relativistic muons passing transversely through the radial electric field components created by the ESQ system. The correction depends on the stored momentum distribution and the tunes of the ring, which has relatively weak vertical focusing. Vertical betatron motions imply that the muons do not orbit the ring in a plane exactly orthogonal to the vertical magnetic field direction. A correction is necessary to account for an average pitch angle associated with their trajectories. A third small correction is necessary because muons that escape the ring during the storage time are slightly biased in initial spin phase compared to the parent distribution. Finally, because two high-voltage resistors in the ESQ network had longer than designed RC time constants, the vertical and horizontal centroids and envelopes of the stored muon beam drifted slightly, but coherently, during each storage ring fill. This led to the discovery of an important phase-acceptance relationship that requires a correction. The sum of the corrections to \\(\\omega_a^m\\) is 0.50 \\(\\pm\\) 0.09 ppm; the uncertainty is small compared to the 0.43 ppm statistical precision of \\(\\omega_a^m\\).