Ab Initio Liquid Hydrogen Muon Cooling Simulations with ELMS in ICOOL

This paper presents new theoretical results on the passage of muons through liquid hydrogen which have been confirmed in a recent experiment. These are used to demonstrate that muon bunches may be compressed by ionisation cooling more effectively than suggested by previous calculations. Muon cooling depends on the differential cross section for energy loss and scattering of muons. We have calculated this cross section for liquid H2 from first principles and atomic data, avoiding traditional assumptions. Thence, 2-D probability maps of energy loss and scattering in mm-scale thicknesses are derived by folding, and stored in a database. Large first-order correlations between energy loss and scattering are found for H2, which are absent in other simulations. This code is named ELMS, Energy Loss & Multiple Scattering. Single particle trajectories may then be tracked by Monte Carlo sampling from this database on a scale of 1 mm or less. This processor has been inserted into the cooling code ICOOL. Significant improvements in 6-D muon cooling are predicted compared with previous predictions based on GEANT. This is examined in various geometries. The large correlation effect is found to have only a small effect on cooling. The experimental scattering observed for liquid H2 in the MUSCAT experiment has recently been reported to be in good agreement with the ELMS prediction, but in poor agreement with GEANT simulation.Comment: 6 pages, 3 figure

Low Cost Real-Time Portable Pulse Oximeter with Wireless Network

To facilitate quicker detection of symptoms of cardiovascular and respiratory disorders, the use of smaller portable wireless sensors which consume less power is an essential requirement. Wireless pulse oximeter are convenient devices which aid to remotely monitor a patient’s heart rate and blood oxygen saturation (SpO ), The result of this studyshows a developed portable, low cost device which can be used to measure the heart rate, and SpO of an individual. To this end, a small pulse oximeter was developed; which used an elastic transmissive mode finger probe to measure the heart rate and SpO . The device could successfully measure these vital signs and display on a LCD screen. The readings taken from individual for a period of one minute shows average heart rate of 75.6 bpm at zero offset and the average SpO readings derived from the device was 98.7% at zero offset. The model designed is also rechargeable to make it more sustainable for use in rural areas where there is insufficient power supply. The prototype pulse oximeter designed is portable, consumes less power and capable of sending processed measured data to an online database via a WLAN network thereby satisfying the criteria for sustainable telemedicine.This device is therefore recommended for use in local hospitals and remote medical centre to aid easier detection and prevention of critical medical disease

Minimal Brownian Ratchet: An Exactly Solvable Model

We develop an exactly-solvable three-state discrete-time minimal Brownian ratchet (MBR), where the transition probabilities between states are asymmetric. By solving the master equations we obtain the steady-state probabilities. Generally the steady-state solution does not display detailed balance, giving rise to an induced directional motion in the MBR. For a reduced two-dimensional parameter space we find the null-curve on which the net current vanishes and detailed balance holds. A system on this curve is said to be balanced. On the null-curve, an additional source of external random noise is introduced to show that a directional motion can be induced under the zero overall driving force. We also indicate the off-balance behavior with biased random noise.Comment: 4 pages, 4 figures, RevTex source, General solution added. To be appeared in Phys. Rev. Let

Simulation of Light Antinucleus-Nucleus Interactions

Creations of light anti-nuclei (anti-deuterium, anti-tritium, anti-He3 and anti-He4) are observed by collaborations at the LHC and RHIC accelerators. Some cosmic ray experiments are aimed to find the anti-nuclei in cosmic rays. To support the experimental studies of the anti-nuclei a Monte Carlo simulation of anti-nuclei interactions with matter is implemented in the Geant4 toolkit. The implementation combines practically all known theoretical approaches to the problem of antinucleon-nucleon interactions.Comment: 8 pages, 5 figure

Super-Kamiokande data and atmospheric neutrino decay

Neutrino decay has been proposed as a possible solution to the atmospheric neutrino anomaly, in the light of the recent data from the Super-Kamiokande experiment. We investigate this hypothesis by means of a quantitative analysis of the zenith angle distributions of neutrino events in Super-Kamiokande, including the latest (45 kTy) data. We find that the neutrino decay hypothesis fails to reproduce the observed distributions of muons.Comment: 6 pages (RevTeX) + 2 figures (Postscript

COMMUNITY AND NETWORK RESPONSES FOR ASSISTING MOBILE VULNERABLE POPULATIONS

The COVID-19 crisis highlighted the increasing vulnerability of individuals, households, and communities. It has almost certainly been even more devastating for those who rely on community networks and organizations for aid but are less able to access aid networks in conditions of reduced mobility. This is the case for “mobile vulnerable populations,” among which include persons experiencing homelessness, victims of human trafficking,immigrants, refugees, and Latinos/as. This report summarizes our research with local Omaha service providers about what they need to serve mobile vulnerable populations in the community, how the pandemic has affected their ability to do so, and whether there have been any substantial and/or institutionalized partnerships between UNO/UNMC and these community organizations. In our research, we used a multi-method approach consisting of a survey of community organization leaders and interviews with organization workers engaged into day-to-day service provision to meet the needs of their clients. Our findingscan be summarized in four main themes: (a) organizations were already under-resourced prior to the pandemic; (b) the impact of the COVID-19 pandemic on organizations was substantial; (c) organizations described similar strengths and innovative responses to the pandemic; and (d) there is a lack of institutionalized collaboration with UNO/UNMC. We argue that building connections between UNO/UNMC and community organizations, as well as assisting in the development of networks among various organizations, is central to the mission of the University of Nebraska system and could benefitthe community more broadly. Concluding, we present four main recommendations: (1) more connections are needed between UNO/UNMC and agencies in the Omaha area; (2) it is likely that there are existing relationships between agency partners and UNO/UNMC faculty, staff and students that could be leveraged; (3) there is an opportunity to prepare students and emphasize workforce growth among providers; and (4) the important work of serving mobile vulnerable populations can be rewarding but also challenging for Omaha providers

SDSS1133: An Unusually Persistent Transient in a Nearby Dwarf Galaxy

While performing a survey to detect recoiling supermassive black holes, we have identified an unusual source having a projected offset of 800 pc from a nearby dwarf galaxy. The object, SDSS J113323.97+550415.8, exhibits broad emission lines and strong variability. While originally classified as a supernova (SN) because of its nondetection in 2005, we detect it in recent and past observations over 63 yr and find over a magnitude of rebrightening in the last 2 years. Using high-resolution adaptive optics observations, we constrain the source emission region to be <12 pc and find a disturbed host-galaxy morphology indicative of recent merger activity. Observations taken over more than a decade show narrow [O III] lines, constant ultraviolet emission, broad Balmer lines, a constant putative black hole mass over a decade of observations despite changes in the continuum, and optical emission-line diagnostics consistent with an active galactic nucleus (AGN). However, the optical spectra exhibit blueshifted absorption, and eventually narrow Fe II and [Ca II] emission, each of which is rarely found in AGN spectra. While this peculiar source displays many of the observational properties expected of a potential black hole recoil candidate, some of the properties could also be explained by a luminous blue variable star (LBV) erupting for decades since 1950, followed by a Type IIn SN in 2001. Interpreted as an LBV followed by a SN analogous to SN 2009ip, the multi-decade LBV eruptions would be the longest ever observed, and the broad Halpha emission would be the most luminous ever observed at late times (>10 yr), larger than that of unusually luminous supernovae such as SN 1988Z, suggesting one of the most extreme episodes of pre-SN mass loss ever discovered.Comment: Accepted for publication in MNRA