Temporal properties of short and long gamma-ray bursts

A temporal analysis was performed on a sample of 100 bright short GRBs with T90 < 2s from the BATSE Current Catalog along with a similar analysis on 319 long bright GRBs with T90 > 2s from the same catalog. The short GRBs were denoised using a median filter and the long GRBs were denoised using a wavelet method. Both samples were subjected to an automated pulse selection algorithm to objectively determine the effects of neighbouring pulses. The rise times, fall times, FWHM, pulse amplitudes and areas were measured and their frequency distributions are presented. The time intervals between pulses were also measured. The frequency distributions of the pulse properties were found to be similar and consistent with lognormal distributions for both the short and long GRBs. The time intervals between the pulses and the pulse amplitudes of neighbouring pulses were found to be correlated with each other. The same emission mechanism can account for the two sub-classes of GRBs.Comment: 3 pages, 8 figures; Proceedings of "Gamma-Ray Burst and Afterglow Astronomy 2001", Woods Hol

Residual Symmetries Applied to Neutrino Oscillations at NOν\nuA and T2K

The results previously obtained from the model-independent application of a generalized hidden horizontal $\mathbb{Z}_2$ symmetry to the neutrino mass matrix are updated using the latest global fits for the neutrino oscillation parameters. The resulting prediction for the Dirac $CP$ phase $\delta_D$ is in agreement with recent results from T2K. The distribution for the Jarlskog invariant $J_\nu$ has become sharper and appears to be approaching a particular region. The approximate effects of matter on long baseline neutrino experiments are explored, and it is shown how the weak interactions between the neutrinos and the particles that make up the Earth can help to determine the mass hierarchy. A similar strategy is employed to show how NO$\nu$A and T2K could determine the octant of $\theta_a (\equiv \theta_{23})$. Finally, the exact effects of matter are obtained numerically in order to make comparisons with the form of the approximate solutions. From this analysis there emerges some interesting features of the effective mass eigenvalues.Comment: 9 pages, 1 table, 17 figure

Transport policy and health inequalities: a health impact assessment of Edinburgh's transport policy

Health impact assessment (HIA) can be used to examine the relationships between inequalities and health. This HIA of Edinburgh's transport policy demonstrates how HIA can examine how different transport policies can affect different population groupings to varying degrees. In this case, Edinburgh's economy is based on tourism, financial services and Government bodies. These need a good transport infrastructure, which maintains a vibrant city centre. A transport policy that promotes walking, cycling and public transport supports this and is also good for health. The HIA suggested that greater spend on public transport and supporting sustainable modes of transport was beneficial to health, and offered scope to reduce inequalities. This message was understood by the City Council and influenced the development of the city's transport and land-use strategies. The paper discusses how HIA can influence public policy

Establishing the potential for using routine data on Incapacity Benefit to assess the local impact of policy initiatives

&lt;i&gt;Background&lt;/i&gt;: Incapacity Benefit (IB) is the key contributory benefit for people who are incapable of work because of illness or disability. &lt;i&gt;Methods&lt;/i&gt;: The aims were to establish the utility of routinely collected data for local evaluation and to provide a descriptive epidemiology of the IB population in Glasgow and Scotland for the period 2000–05 using data supplied by the Department for Work and Pensions. &lt;i&gt;Results&lt;/i&gt;: Glasgow's IB population is large in absolute and relative terms but is now falling, mainly due to a decrease in on flow. Claimants, tend to be older, have a poor work history and suffer from mental health problems. The rate of decline has been greater in Glasgow than Scotland, although the rate of on flow is still higher. &lt;i&gt;Conclusions&lt;/i&gt;: Department for Work and Pensions (DWP) data can be used locally to provide important insights into the dynamics of the IB population. However, to be truly useful, more work needs to be undertaken to combine the DWP data with other information

SP-100 reactor with Brayton conversion for lunar surface applications

Examined here is the potential for integrating Brayton-cycle power conversion with the SP-100 reactor for lunar surface power system applications. Two designs were characterized and modeled. The first design integrates a 100-kWe SP-100 Brayton power system with a lunar lander. This system is intended to meet early lunar mission power needs while minimizing on-site installation requirements. Man-rated radiation protection is provided by an integral multilayer, cylindrical lithium hydride/tungsten (LiH/W) shield encircling the reactor vessel. Design emphasis is on ease of deployment, safety, and reliability, while utilizing relatively near-term technology. The second design combines Brayton conversion with the SP-100 reactor in a erectable 550-kWe powerplant concept intended to satisfy later-phase lunar base power requirements. This system capitalizes on experience gained from operating the initial 100-kWe module and incorporates some technology improvements. For this system, the reactor is emplaced in a lunar regolith excavation to provide man-rated shielding, and the Brayton engines and radiators are mounted on the lunar surface and extend radially from the central reactor. Design emphasis is on performance, safety, long life, and operational flexibility

The pre-WDVV ring of physics and its topology

We show how a simplicial complex arising from the WDVV (Witten-Dijkgraaf-Verlinde-Verlinde) equations of string theory is the Whitehouse complex. Using discrete Morse theory, we give an elementary proof that the Whitehouse complex $\Delta_n$ is homotopy equivalent to a wedge of $(n-2)!$ spheres of dimension $n-4$. We also verify the Cohen-Macaulay property. Additionally, recurrences are given for the face enumeration of the complex and the Hilbert series of the associated pre-WDVV ring.Comment: 13 pages, 4 figures, 2 table

Department of Defense's 2015 retirement plan cost analysis

MBA Professional ReportThe new military retirement system is advertised to significantly reduce the Department of Defense's (DOD) monetary outlays over the short and long term. These savings are generated through a variety of assumptions outside of the department's control. The variables that have the greatest impact over cost savings are controlled by service members' (SM) actions, choices, and federal interest rates. Critical analysis of these variables could potentially affect future cost savings and is key in budget preparation and future spending plans. This MBA report presents a sensitivity analysis on three separate variables that have a significant impact on retirement costs. Realistic manipulation of these independent variables will show short-term versus long-term cost savings. Additionally, a high-cost and low-cost scenario is explored. With cost scenarios differing up to $321 billion, DOD needs to be aware of the potential effects of future outlays. It is recommended that DOD conduct additional economic research and acquire further data on the preferences of current SMs in order to provide a more narrow range of cost savings.http://archive.org/details/departmentofdefe1094549480Lieutenant Commander, United States NavyLieutenant, United States NavyLieutenant, United States NavyApproved for public release; distribution is unlimited

Comparison of dynamic isotope power systems for distributed planet surface applications

Dynamic isotope power system (DIPS) alternatives were investigated and characterized for the surface mission elements associated with a lunar base and subsequent manned Mars expedition. System designs based on two convertor types were studied. These systems were characterized parametrically and compared over the steady-state electrical output power range 0.2 to 20 kWe. Three methods of thermally integrating the heat source and the Stirling heater head were considered, depending on unit size. Figures of merit were derived from the characterizations and compared over the parametric range. Design impacts of mission environmental factors are discussed and quantitatively assessed

Temporal properties of the short gamma-ray bursts

A temporal analysis has been performed on a sample of 100 bright gamma-ray bursts (GRBs) with T90<2s from the BATSE current catalog. The GRBs were denoised using a median filter and subjected to an automated pulse selection algorithm as an objective way of idenitifing the effects of neighbouring pulses. The rise times, fall times, FWHM, pulse amplitudes and areas were measured and the frequency distributions are presented here. All are consistent with lognormal distributions. The distribution of the time intervals between pulses is not random but consistent with a lognormal distribution. The time intervals between pulses and pulse amplitudes are highly correlated with each other. These results are in excellent agreement with a similar analysis that revealed lognormal distributions for pulse properties and correlated time intervals between pulses in bright GRBs with T90>2s. The two sub-classes of GRBs appear to have the same emission mechanism which is probably caused by internal shocks. They may not have the same progenitors because of the generic nature of the fireball model.Comment: 4 pages, 7 figure