Gamma ray lines from TeV dark matter

We calculate, using unitarity, a lower bound on the branching ratio $\chi\chi\to \gamma\gamma$ and $\chi\chi\to \gamma Z$, where $\chi$ is any halo dark matter particle that has $W^+W^-$ as one of the major annihilation modes. Examples of such particles are supersymmetric particles with a dominant Higgsino component, or heavy triplet neutrinos. A substantial branching ratio is found for the $\gamma\gamma$ and $\gamma Z$ modes. We estimate the strength of the monoenergetic $\gamma$ ray lines that result from such annihilations in the Galactic or LMC halos. (Latex file; 2 compressed uuencoded postscript figures available by anonymous ftp from vanosf.physto.se in file pub/figures/lines.uu)Comment: 11 pages, USITP-94-03; PAR-LPTHE 94-0

U.S. State-Level Carbon Dioxide Emissions: A Spatial-Temporal Econometric Approach of the Environmental Kuznets Curve

One of the major criticisms of past environmental Kuznets curve (EKC) studies is that the spatiotemporal aspects within the data have largely been ignored. By ignoring the spatial aspect of pollution emissions past estimates of the EKC implicitly assume that a region’s emissions are unaffected by events in neighboring regions (i.e., assume there are no transboundary pollution emissions between neighbors). By ignoring the spatial aspects within the data several past estimates of the EKC could have generated biased or inconsistent regression results. By ignoring the temporal aspect within the data several past estimates of the EKC could have generated spurious regression results or misspecified t and F statistics. To address this potential misspecification we estimate the relationship between state-level carbon dioxide emissions and income (GDP) accounting for both the spatiotemporal components within the data. Specifically, we estimate a dynamic spatiotemporal panel model using a newly proposed robust, spatial fixed effects model. This new estimation scheme is appropriate for panels with large N and T. Consistent with the EKC hypothesis we find the inverted-U shaped relationship between CO2 emissions and income. Further, we find adequate evidence that carbon dioxide emissions and state-level GDP are temporally and spatially dependent. These findings offer policy implications for both interstate energy trade and pollution emission regulations. These implications are particularly important for the formulation of national policies related to the 2009 Copenhagen Treaty in which the U.S. has committed to significantly reduce greenhouse gas emissions over the next twenty years.Environmental Kuznets Curve, Carbon Dioxide, Spatial Econometrics, Panel Data Econometrics, Time Series Analysis, Environmental Economics, Pollution Economics, Environmental Economics and Policy, Q50, Q53, Q43, C01, C33,

Clumpy Neutralino Dark Matter

We investigate the possibility to detect neutralino dark matter in a scenario in which the galactic dark halo is clumpy. We find that under customary assumptions on various astrophysical parameters, the antiproton and continuum gamma-ray signals from neutralino annihilation in the halo put the strongest limits on the clumpiness of a neutralino halo. We argue that indirect detection through neutrinos from the Earth and the Sun should not be much affected by clumpiness. We identify situations in parameter space where the gamma-ray line, positron and diffuse neutrino signals from annihilations in the halo may provide interesting signals in upcoming detectors.Comment: 19 pages, 10 eps-figures (included), LaTeX, uses RevTe

A Spatiotemporal Fixed Effects Estimation of U.S. State-Level Carbon Dioxide Emissions

One of the major shortcommings of past environmental Kuznets curve (EKC) studies is that the spatiotemporal aspects within the data have largely been ignored. By ignoring the spatial aspect of pollution emissions past estimates of the EKC implicitly assume that a region’s emissions are unaffected by events in neighboring regions (i.e., assume there are no transboundary pollution emissions between neighbors). By ignoring the spatial aspects within the data several past estimates of the EKC could have generated biased or inconsistent regression results. By ignoring the temporal aspect within the data several past estimates of the EKC could have generated spurious regression results or misspecified t and F statistics. To address this potential misspecification we estimate the relationship between state-level carbon dioxide emissions and income (GDP) accounting for both the spatiotemporal components within the data. Specifically, we estimate a dynamic spatiotemporal panel model using a newly proposed robust, spatial fixed effects model. This new estimation scheme is appropriate for panels with large N and T. Consistent with the EKC hypothesis we find the inverted-U shaped relationship between CO2 emissions and income. Further, we find adequate evidence that the underlying economic processes driving carbon dioxide emissions and state-level GDP are temporally and spatially dependent. These findings offer policy implications for both interstate energy trade and pollution emission regulations. These implications are particularly important for the formulation of national policies related to the 2009 Copenhagen Treaty in which the U.S. has committed to significantly reduce greenhouse gas emissions over the next twenty years.Pollution Economics, Environmental Kuznets Curve, Spatial Econometrics, Dynamic Panel Data, Carbon Dioxide Emissions, Global Climate Change, Environmental Economics and Policy, Research Methods/ Statistical Methods, Resource /Energy Economics and Policy, C33, C51, Q43, Q50, Q53, Q58,

Valuing Farmland Protection with Choice Experiments That Incorporate Preference Heterogeneity: Does Policy Guidance Depend On the Econometric Fine Print?

Although mixed logit models are common in stated preference applications, resulting welfare estimates can be sensitive to minor changes in specification. This can be of critical relevance for policy and welfare analysis, particularly if policymakers are unaware of practical implications. Drawing from an application to agricultural conservation in Georgia, this paper quantifies the sensitivity of welfare estimates to common variations in mixed logit specification and assesses practical implications for policy guidance. Results suggest that practitioners may wish to reevaluate modeling and reporting procedures to reflect the welfare and policy implications of common but often unnoticed variations in model specification.Willingness to Pay, Conservation Easement, PACE, Mixed Logit, Stated Preference, Environmental Economics and Policy, Land Economics/Use, Research Methods/ Statistical Methods, Q24, Q51,

Early search for supersymmetric dark matter models at the LHC without missing energy

We investigate early discovery signals for supersymmetry at the Large Hadron Collider without using information about missing transverse energy. Instead we use cuts on the number of jets and isolated leptons (electrons and/or muons). We work with minimal supersymmetric extensions of the standard model, and focus on phenomenological models that give a relic density of dark matter compatible with the WMAP measurements. An important model property for early discovery is the presence of light sleptons, and we find that for an integrated luminosity of only 200--300 pb$^{-1}$ at a center-of-mass energy of 10 TeV models with gluino masses up to $\sim 700$ GeV can be tested.Comment: 28 pages, 12 figures; published versio

WOULD PEOPLE RATHER PAY TAXES OR TRADE TAXES TO PAY FOR ENVIRONMENTAL GOODS? A GROUND WATER QUALITY CASE

The potential sensitivity of environmental resource valuation to payment vehicles is of interest to researchers and decision-makers involved in estimating and applying these numbers. A conceptual model is developed which provides insight into how the different payment vehicles of a special tax and a tax reallocation affects the willingness to pay (WTP) for environmental goods. Hypothesis testing using contingent valuation data suggests WTP with a tax reallocation is higher than WTP with a special tax for ground water quality protection in Georgia and Maine.Environmental Economics and Policy, Public Economics,

Earning the MFA: Investigations of Curricula and Pedagogies as a Means of Developing Graduate Studio Art Students\u27 Sense of Self

This research study critically examined personal and professional issues related to visual arts MFA graduate students and myself as we participated in a course entitled, "Issues of Relevance and Character in the Fine Arts." The course explored a graduate student\u27s developing sense of self and its impact on the different roles he or she often embodies while pursuing an MFA (individual, student, artist, teacher, and future professional). Employing an educational participatory action research methodology, I was also a participant in the study and documented the oral, written, and visual data that emerged from the participants\u27 interactions. This paper briefly reviews studies conducted on graduate student development, students in MFA programs, and the historical development of the MFA degree. Findings indicated the following: First, strong convictions seemed to be intrinsic to the participants\u27 pursuit of their MFA degrees, and each participant expressed interest in teaching in higher education. Second, participating in the course seemed to offer a receptive platform to convey the voices of the "characters" the participants embodied as MFA students. Their personal and professional development was influenced by the complex relationships they shared with others in their MFA programs. A third theme addressed the impact of my participation within the study. With an established background in art making and teaching within Art and Visual Culture Education, the findings suggest that I was able to empathize with the three other participants on several fronts. The implications of this research study suggest the need for more action research studies of MFA graduate students

Re-engage with the world for global health and animal welfare

Wiebers & Feigin (2020) make a strong argument for measures that would limit future zoonoses, such as the COVID-19 pandemic, by closing live-animal markets, changing our habits of food consumption and production, and reducing habitat destruction. These would help human health, animal welfare, and conservation of at-risk wildlife all at the same time. China’s command-and-control government can accomplish some of these things by edict, but slower-to-act western democracies play a surprisingly large role in these global problems by the power of their consumerism, including the illicit wildlife trade. We citizens need to insist that our government use all of its diplomatic soft power to engage (or re-engage) with other nations, and with global institutions such as the World Health Organization, various United Nations programs, and parties to treaties (some of which we still need to ratify, others of which we need to enforce at home) aimed at solving the interlocking global crises of species endangerment, habitat destruction, climate change, and emerging infectious disease