Potential Impacts of Subprime Carbon on Australia’s Impending Carbon Market

This paper examines the potential impacts of subprime carbon credits on the impending Australian carbon market. Subprime carbon could potentially be created in carbon offset markets that lack adequate regulation, as projects face risks that can overstate emissions abatement. Recent research suggests that subprime carbon credits will likely cause significant price instability in carbon markets, with some authors drawing parallels to the US market for mortgage backed securities during the subprime mortgage crisis (Chan, 2009). To assess the impacts of subprime carbon credits on the impending Australian carbon market, carbon price fundamentals are examined using a marginal abatement cost curve for the year 2020. The 2020 Australian marginal abatement cost curve is derived using a bottom-up model of the Australian electricity sector, as well as findings by the (DCC, 2009) and (McKinsey, 2008). Impacts are evaluated under several scenarios, which consider different trading scheme limits on the use of offsets; different proportions of offset credits that are subprime; and different emissions reduction targets. The results suggest that subprime carbon credits will always result in overall emissions reductions to be overstated, while sometimes increasing price volatility in the carbon market, depending on the steepness of the marginal abatement cost curve, the proportion of offset credits that are subprime, and the trading schemes limits on the use of offsets. We conclude that carbon markets could benefit significantly from a carbon offsets regulator, which would ensure the environmental and financial integrity of offset credits.Carbon Offsets, Marginal Abatement Cost, Carbon Market Regulation, Subprime Carbon

Precise Estimates of the Higgs Mass in Heavy SUSY

In supersymmetric models, very heavy stop squarks introduce large logarithms into the computation of the Higgs boson mass. Although it has long been known that in simple cases these logs can be resummed using effective field theory techniques, it is technically easier to use fixed-order formulas, and many public codes implement the latter. We calculate three- and four-loop next-to-next-to-leading-log corrections to the Higgs mass and compare the fixed order formulas numerically to the resummation results in order to estimate the range of supersymmetry scales where the fixed-order results are reliable. We find that the four-loop result may be accurate up to a few tens of TeV. We confirm an accidental cancellation between different three-loop terms, first observed in S. P. Martin, Phys. Rev. D 75, 055005 (2007), and show that it persists to higher scales and becomes more effective with the inclusion of higher radiative corrections. Existing partial three-loop calculations that include only one of the two cancelling terms may overestimate the Higgs mass. We give analytic expressions for the three- and four-loop corrections in terms of Standard Model parameters and provide a complete dictionary for translating parameters between the SM and the MSSM and the \MSbar and \DRbar renormalization schemes.Comment: 34 pages, 6 figures. Added acknowledgments in v2. Corrected typos from published version in PRD in v

Prospects for Higgs Searches at the Tevatron and LHC in the MSSM with Explicit CP-violation

We analyze the Tevatron and Large Hadron Collider (LHC) reach for the Higgs sector of the Minimal Supersymmetric Standard Model (MSSM) in the presence of explicit CP-violation. Using the most recent studies from the Tevatron and LHC collaborations, we examine the CPX benchmark scenario for a range of CP-violating phases in the soft trilinear and gluino mass terms and compute the exclusion/discovery potentials for each collider on the $(M_{H^+}, \tan\beta)$ plane. Projected results from Standard Model (SM)-like, non-standard, and charged Higgs searches are combined to maximize the statistical significance. We exhibit complementarity between the SM-like Higgs searches at the LHC with low luminosity and the Tevatron, and estimate the combined reach of the two colliders in the early phase of LHC running.Comment: 38 pages, 9 figures; References added, minor additions to Appendix

Aid effectiveness for poverty reduction: lessons from cross-country analyses, with a special focus on vulnerable countries

Ferdi, Working paper P96, marsFollowing the adoption of the MDG, particularly the first one that is to reduce poverty by half between 1995 and 2015, numerous studies have examined how external aid can contribute to their achievement. The formula "doubling aid to reduce the poverty by half" relied on the implicit assumption that aid was an effective instrument for poverty reduction. The formula and corresponding assumption have been debated. Two opposite views clearly appeared, one, represented by Jeffrey Sachs in his End of Poverty, underlining the need for a big push to get low income countries out of poverty traps, the other one, illustrated by the attacks of William Easterly against aid as a support of a big push and the idea of a poverty trap, and also including arguments about a limited absorptive capacity. Elsewhere we have argued that the absorptive capacity of aid depends on aid modalities and can be enhanced by a reform of aid, a way by which big push and absorptive capacity views can be reconciled and to which we come back later (Guillaumont and Guillaumont Jeanneney, 2010).Actually the academic debate on aid effectiveness of the first millennium decade has been dominated by another controversy, relying on cross country regressions and initiated by the highly influential paper of Burnside and Dollar (2000). After so many cross country studies following their paper, supporting or, more often, criticizing it, there seems to be a temptation to consider this research orientation as a deadlock and to switch to micro impact analysis. Whatever the importance and need of impact micro-analyses, we argue that it would be a dangerous dismissal to give up the cross-section approach, for several reasons. First the methodological weaknesses of many studies does not entail that other ones relying on better methodology and data cannot lead to more robust results. Second, since cross section studies on aid effectiveness will never be totally given up, there is a risk to see only the most provocative (and possibly least robust) retaining the attention of media and policy makers, a policy challenge to be kept in mind in the orientation of research. Finally micro studies and impact analyses, while they supply policy makers with useful information in a given context, are not an appropriate tool for assessing the impact of macro-economic features of countries on aid effectiveness.The aim of this paper, relying on results of the cross country literature on aid effectiveness, and drawing only on those we consider as particularly relevant and robust is to examine how aid can contribute to poverty reduction, with a special focus on the way it can address the vulnerability of many developing countries

Evaluation of Soil Moisture Retrieval from the ERS and Metop Scatterometers in the Lower Mekong Basin

The natural environment and livelihoods in the Lower Mekong Basin (LMB) are significantly affected by the annual hydrological cycle. Monitoring of soil moisture as a key variable in the hydrological cycle is of great interest in a number of Hydrological and agricultural applications. In this study we evaluated the quality and spatiotemporal variability of the soil moisture product retrieved from C-band scatterometers data across the LMB sub-catchments. The soil moisture retrieval algorithm showed reasonable performance in most areas of the LMB with the exception of a few sub-catchments in the eastern parts of Laos, where the land cover is characterized by dense vegetation. The best performance of the retrieval algorithm was obtained in agricultural regions. Comparison of the available in situ evaporation data in the LMB and the Basin Water Index (BWI), an indicator of the basin soil moisture condition, showed significant negative correlations up to R = −0.85. The inter-annual variation of the calculated BWI was also found corresponding to the reported extreme hydro-meteorological events in the Mekong region. The retrieved soil moisture data show high correlation (up to R = 0.92) with monthly anomalies of precipitation in non-irrigated regions. In general, the seasonal variability of soil moisture in the LMB was well captured by the retrieval method. The results of analysis also showed significant correlation between El Niño events and the monthly BWI anomaly measurements particularly for the month May with the maximum correlation of R = 0.88

Dark Light Higgs

We study a limit of the nearly-Peccei-Quinn-symmetric Next-to-Minimal Supersymmetric Standard Model possessing novel Higgs and dark matter (DM) properties. In this scenario, there naturally co-exist three light singlet-like particles: a scalar, a pseudoscalar, and a singlino-like DM candidate, all with masses of order 0.1-10 GeV. The decay of a Standard Model-like Higgs boson to pairs of the light scalars or pseudoscalars is generically suppressed, avoiding constraints from collider searches for these channels. For a certain parameter window annihilation into the light pseudoscalar and exchange of the light scalar with nucleons allow the singlino to achieve the correct relic density and a large direct detection cross section consistent with the CoGeNT and DAMA/LIBRA preferred region simultaneously. This parameter space is consistent with experimental constraints from LEP, the Tevatron, and Upsilon- and flavor physics.Comment: 4 pages, 4 figures, final version for Phys. Rev. Let

Prospects for MSSM Higgs Searches at the Tevatron

We analyze the Tevatron reach for neutral Higgs bosons in the Minimal Supersymmetric Standard Model (MSSM), using current exclusion limits on the Standard Model Higgs. We study four common benchmark scenarios for the soft supersymmetry-breaking parameters of the MSSM, including cases where the Higgs decays differ significantly from the Standard Model, and provide projections for the improvements in luminosity and efficiency required for the Tevatron to probe sizeable regions of the $(m_A, \tan\beta)$ plane.Comment: 23 pages, 21 figures; References added, benchmark scenarios and figures updated, webpage link adde

SUSY-Breaking Parameters from RG Invariants at the LHC

We study Renormalization Group invariant (RGI) quantities in the Minimal Supersymmetric Standard Model and show that they are a powerful and simple instrument for testing high scale models of supersymmetry (SUSY)-breaking. For illustration, we analyze the frameworks of minimal and general gauge mediated (MGM and GGM) SUSY-breaking, with additional arbitrary soft Higgs mass parameters at the messenger scale. We show that if a gaugino and two first generation sfermion soft masses are determined at the LHC, the RGIs lead to MGM sum rules that yield accurate predictions for the other gaugino and first generation soft masses. RGIs can also be used to reconstruct the fundamental MGM parameters (including the messenger scale), calculate the hypercharge D-term, and find relationships among the third generation and Higgs soft masses. We then study the extent to which measurements of the full first generation spectrum at the LHC may distinguish different SUSY-breaking scenarios. In the case of MGM, although most deviations violate the sum rules by more than estimated experimental errors, we find a 1-parameter family of GGM models that satisfy the constraints and produce the same first generation spectrum. The GGM-MGM degeneracy is lifted by differences in the third generation masses and the messenger scales.Comment: (v1) 30 pages; (v2) mislabeling in figs 2 and 3 corrected, version accepted for publication in Phys. Rev.

Turbulent Drag Reduction of polyelectrolyte (DNA) solutions: relation with the elongational viscosity

We report measurements of turbulent drag reduction of two different polyelectrolyte solutions: DNA and hydrolyzed Polyacrylamide. Changing the salt concentration in the solutions allows us to change the flexibility of the polymer chains. For both polymers the amount of drag reduction was found to increase with the flexibility. Rheological studies reveal that the elongational viscosity of the solutions increases simultaneously. Hence we conclude that the elongational viscosity is the pertinent macroscopic quantity to describe the ability of a polymer to cause turbulent drag reduction