A Conversation to Be Inserted Between the Franklin\u27s Tale and the Physician\u27s Tale

Fiction by Tom Misch

Nuclear neutrino energy spectra in high temperature astrophysical environments

Astrophysical environments that reach temperatures greater than $\sim$ 100 keV can have significant neutrino energy loss via both plasma processes and nuclear weak interactions. We find that nuclear processes likely produce the highest-energy neutrinos. Among the important weak nuclear interactions are both charged current channels (electron capture/emission and positron capture/emission) and neutral current channels (de-excitation of nuclei via neutrino pair emission). We show that in order to make a realistic prediction of the nuclear neutrino spectrum, one must take nuclear structure into account; in some cases, the most important transitions may involve excited states, possibly in both parent and daughter nuclei. We find that the standard technique of producing a neutrino energy spectrum by using a single transition with a Q-value and matrix element chosen to fit published neutrino production rates and energy losses will not accurately capture important spectral features.Comment: 11 pages, 17 figure

Growth and welfare maximization in models of public finance and endogenous growth

This paper evaluates the trade-off between growth and welfare maximization from two perspectives. Firstly, it synthesizes and extends endogenous growth models with public finance to compare growth and welfare maximizing tax rates. Secondly, it examines the distinct model outcomes in terms of their growth rates and welfare levels. This comparison highlights the range of trade-offs: the growth maximizing tax rate can be above, below, or equal to the welfare maximizing equivalent. We find however that even relatively large differences in growth and welfare maximizing tax rates translate into relatively small differences in growth rates, and, in some cases, welfare levels. --Economic Growth,Productive Public Spending,Optimal Fiscal Policy

Growth and Welfare Maximization in Models of Public Finance and Endogenous Growth

This paper evaluates the trade-off between growth and welfare maximization from two perspectives. Firstly, it synthesizes and extends endogenous growth models with public finance to compare the growth and welfare maximizing tax rates. Secondly, it examines the distinct model outcomes in terms of the growth rates and welfare levels. This comparison highlights the range of trade-offs: the growth maximizing tax rate can lie above, below, or on the welfare maximizing equivalent. We find however that even relatively large differences in growth and welfare maximizing tax rates translate into relatively small differences in growth rates, and, in some cases, welfare levels.Economic Growth, Productive Public Spending, Optimal Fiscal Policy

Neutrino Spectra from Nuclear Weak Interactions in sdsd-Shell Nuclei Under Astrophysical Conditions

We present shell model calculations of nuclear neutrino energy spectra for 70 $sd$-shell nuclei over the mass number range $A=21-35$. Our calculations include nuclear excited states as appropriate for the hot and dense conditions characteristic of pre-collapse massive stars. We consider neutrinos produced by charged lepton captures and decays and, for the first time in tabular form, neutral current nuclear deexcitation, providing neutrino energy spectra on the Fuller-Fowler-Newman temperature-density grid for these interaction channels for each nucleus. We use the full $sd$-shell model space to compute initial nuclear states up to 20 MeV excitation with transitions to final states up to 35-40 MeV, employing a modification of the Brink-Axel hypothesis to handle high temperature population factors and the nuclear partition functions.Comment: 15 pages, 8 figures. Until data available at JINA-CEE, contact GWM for spectra data file

Neutrino Pair Emission from Hot Nuclei During Stellar Collapse

We present shell-model calculations showing that residual interaction-induced configuration mixing enhances the rate of neutral current de-excitation of thermally excited nuclei into neutrino-antineutrino pairs. Though our calculations reinforce the conclusions of previous studies that this process is the dominant source of neutrino pairs near the onset of neutrino trapping during stellar collapse, our shell-model result has the effect of increasing the energy of these pairs, possibly altering their role in entropy transport in supernovae.Comment: 9 pages, 8 figure

Modification of the Brink-Axel Hypothesis for High Temperature Nuclear Weak Interactions

We present shell model calculations of electron capture strength distributions in A=28 nuclei and computations of the corresponding capture rates in supernova core conditions. We find that in these nuclei the Brink-Axel hypothesis for the distribution of Gamow-Teller strength fails at low and moderate initial excitation energy, but may be a valid tool at high excitation. The redistribution of GT strength at high initial excitation may affect capture rates during collapse. If these trends which we have found in lighter nuclei also apply for the heavier nuclei which provide the principal channels for neutronization during stellar collapse, then there could be two implications for supernova core electron capture physics. First, a modified Brink-Axel hypothesis could be a valid approximation for use in collapse codes. Second, the electron capture strength may be moved down significantly in transition energy, which would likely have the effect of increasing the overall electron capture rate during stellar collapse.Comment: 15 pages, 19 figure

Simulating Distributed Battery and Solar Array Placement for Voltage Regulation

Energy storage has been around for many years in the US, mainly in the form of pumped hydro. However, in recent years, other storage technologies have developed quickly, with lithium ion batteries receiving significant investment and delivering technological and price improvements. Electricity storage has the potential to assist the US in transitioning to a smarter grid, as well as enabling increasing amounts of renewable generation to connect to the grid, without costly reinforcement works. Electricity storage can be co-located with power generation assets, installed along distribution systems for network services, or placed behind the meter, i.e., on the customer’s premises. This thesis focuses on the latter case. Modern day electrical grids are complex and varied. Using a representative of a large number of grids we can simulate real world conditions and show how the system reacts to distributed solar arrays but can also show how the system can recover from voltage failures using residential sized distributed battery banks. It is hypothesized that through distributed use of battery systems that energy grids can facilitate a larger amount of renewable energy in regard to voltage and current limitations. The tasks to be performed include the following: • Establish a base case network using the IEEE test feeder with local TMY data and local load data with Gridlab-D • Establish a distributed and isolated number of solar arrays that real world outputs to cover how the grid would begin to fail relative to voltage and current limitations • Study the ability of the grid to recover from voltage violations with the use of residential sized distributed battery systems using three utilization variations. Time of use shifting, peak shaving, and negative power shifting. Based upon the found data we can discuss the added benefits of distributed battery systems and how they can be used to harden the grid against voltage failures

Fiscal policy and growth with complementarities and constraints on government

This paper considers the implications of complementarity in private production and constraints on government for optimal fiscal policy. Using an endogenous growth model with public finance, it derives three central results which modify findings in the literature under standard assumptions. First, it shows that optimal public spending composition and taxation are interrelated so that first- and second-best fiscal policies differ. Second, it shows that the growth-maximizing fiscal policy is affected by preference parameters. Third, it shows that with budget rigidities and informational limitations, knowledge about the optimal fiscal policy parameter values is not necessary for growth-enhancing fiscal policy adjustments. --Imperfect Knowledge,Economic Growth,Productive Public Spending,Optimal Fiscal Policy

Employing Template-Directed Assembly to Create a Novel Coagulation Assay

Blood coagulation is an important aspect of hemostasis in the human body. Under normal circumstances, the blood coagulates using two different pathways, the intrinsic and the extrinsic. The extrinsic pathway works to counteract trauma but may lead to stroke forming clots. Components for an assay were created so that an assay could be designed to test the functionality of the proteins involved in the clotting cascade: Tissue Factor, factor VII, and factor X when used in conjunction with Template Directed Assembly (TDA) on a nickel-nitriloacetic acid (Ni-NTA) derived liposome