18,312 research outputs found
High Scale Boundary Conditions in Models with Two Higgs Doublets
We investigate high scale boundary conditions on the quartic Higgs-couplings
and their -functions in the Type-II Two Higgs Doublet Model and the
Inert Doublet Model. These conditions are associated with two possible UV
physics scenarios: the Multiple Point Principle, in which the potential
exhibits a second minimum at , and Asymptotic Safety, where the scalar
couplings run towards an interacting UV fixed point at high scales. We employ
renormalisation group running at two-loops and apply theoretical and
experimental constraints to their parameter spaces. We find neither model can
simultaneously accommodate the MPP whilst also providing realistic masses for
both the Higgs and the top quark. However, we do find regions of parameter
space compatible with Asymptotic Safety.Comment: 25 pages, 13 figures (25 plots); v3: version accepted for publicatio
The Costs, Wealth Effects, and Determinants of International Capital Raising: Evidence from Public Yankee Bonds
This paper examines the costs, wealth effects, and determinants of international capital raising for a sample of 260 public debt issues made by non-U.S. firms in the U.S. (Yankee) market. We find that investors demand economically significant premiums on bonds issued by firms that are located in countries that do not protect investors' rights and do not have a prior history of on-going disclosure. The results provide support for the literature that suggests better legal protections and more detailed information disclosure increases the price investors will pay for financial assets. We also find that the average stock price reaction to Yankee bond offerings is significantly positive and that abnormal returns are largest for first-time Yankee bond issuers. In addition, we show that foreign firms tend to issue in the Yankee market when the relative interest cost is low, indicating that potential differences in borrowing costs influence where firms choose to sell bonds.http://deepblue.lib.umich.edu/bitstream/2027.42/39829/3/wp445.pd
Nuclear rocket propulsion. NASA plans and progress, FY 1991
NASA has initiated planning for a technology development project for nuclear rocket propulsion systems for space explorer initiative (SEI) human and robotic missions to the moon and Mars. An interagency project is underway that includes the Department of Energy National Laboratories for nuclear technology development. The activities of the project planning team in FY 1990 and 1991 are summarized. The progress to date is discussed, and the project plan is reviewed. Critical technology issues were identified and include: (1) nuclear fuel temperature, life, and reliability; (2) nuclear system ground test; (3) safety; (4) autonomous system operation and health monitoring; and (5) minimum mass and high specific impulse
The Costs, Wealth Effects, and Determinants of International Capital Raising: Evidence from Public Yankee Bonds
This paper examines the costs, wealth effects, and determinants of international capital raising for a sample of 260 public debt issues made by non-U.S. firms in the U.S. (Yankee) market. We find that investors demand economically significant premiums on bonds issued by firms that are located in countries that do not protect investors' rights and do not have a prior history of on-going disclosure. The results provide support for the literature that suggests better legal protections and more detailed information disclosure increases the price investors will pay for financial assets. We also find that the average stock price reaction to Yankee bond offerings is significantly positive and that abnormal returns are largest for first-time Yankee bond issuers. In addition, we show that foreign firms tend to issue in the Yankee market when the relative interest cost is low, indicating that potential differences in borrowing costs influence where firms choose to sell bonds.Banking and Finance, Yankee bonds, International Capital Raising
Security fungibility and the cost of capital: evidence from global bonds
This paper examines the potential benefits of security fungibility by conducting the first comprehensive analysis of Global bonds. Unlike other debt securities, Global bonds’ fungibility allows them to be placed simultaneously in bond markets around the world; they trade, clear and settle efficiently within as well as across markets. We test the impact of issuing these securities on firms’ cost of capital, issuing costs, liquidity and shareholder wealth. Using a sample of 230 Global bond issues by 94 companies from the U.S. and abroad over the period 1996-2003, we find that firms are able to lower their cost of (debt) capital by issuing these fungible securities. We also document that the stock price reaction to the announcement of Global bond issuance is positive and significant, while comparable domestic and Eurobond issues over the same time period are associated with insignificant changes in shareholder wealth. JEL Classification: F3, G1, G3cost of capital, Global bonds, international capital raising, security fungibility
Next-to-leading order predictions for WW+jet production
In this work we report on a next-to-leading order calculation of WW + jet
production at hadron colliders, with subsequent leptonic decays of the W-bosons
included. The calculation of the one-loop contributions is performed using
generalized unitarity methods in order to derive analytic expressions for the
relevant amplitudes. These amplitudes have been implemented in the parton-level
Monte Carlo generator MCFM, which we use to provide a complete next-to-leading
order calculation. Predictions for total cross-sections, as well as
differential distributions for several key observables, are computed both for
the LHC operating at 14 TeV as well as for a possible future 100 TeV
proton-proton collider.Comment: 14 pages, 7 figures; v2: several references added, 2 typos corrected.
Corresponds to published journal versio
Design of a Recreational Fishing Survey and Mark-Recapture Study for the Blue Crab, Callinectes sapidus, in Chesapeake Bay
The development of bay wide estimates of recreational harvest has been identified as a high priority by the Chesapeake Bay Scientific Advisory Committee (CBSAC) and by the Chesapeake Bay Program as reflected in the Chesapeake Bay Blue Crab Fishery Management Plan (Chesapeake Bay Program 1996). In addition, the BiState Blue Crab Commission (BBCAC), formed in 1996 by mandate from the legislatures of Maryland and Virginia to advise on crab
management, has also recognized the importance of estimating the levels and trends in catches in the recreational fishery. Recently, the BBCAC has adopted limit and target biological reference points. These analyses have been predicated on assumptions regarding the relative magnitude of the recreational and commercial catch. The reference points depend on determination of the total
number of crabs removed from the population. In essence, the number removed by the various fishery sectors, represents a minimum estimate of the population size. If a major fishery sector is not represented, the total population will be accordingly underestimated. If the relative contribution of the unrepresented sector is constant over time and harvests the same components of
the population as the other sectors, it may be argued that the population estimate derived from the other sectors is biased but still adequately represents trends in population size over time. If either of the two constraints mentioned above is not met, the validity of relative trends over time is suspect. With the recent increases in the human population in the Chesapeake Bay watershed, there is reason to be concerned that the recreational catch may not have been a constant proportion of the total harvest over time. It is important to assess the catch characteristics and the magnitude of the recreational fishery to evaluate this potential bias. (PDF contains 70 pages
A parameter uniform fitted mesh method for a weakly coupled system of two singularly perturbed convection-diffusion equations
In this paper, a boundary value problem for a singularly perturbed linear
system of two second order ordinary differential equations of convection-
diffusion type is considered on the interval [0, 1]. The components of the
solution of this system exhibit boundary layers at 0. A numerical method
composed of an upwind finite difference scheme applied on a piecewise uniform
Shishkin mesh is suggested to solve the problem. The method is proved to be
first order convergent in the maximum norm uniformly in the perturbation
parameters. Numerical examples are provided in support of the theory
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