18 research outputs found
The 2010 very high energy gamma-ray flare & 10 years of multi-wavelength observations of M 87
Abridged: The giant radio galaxy M 87 with its proximity, famous jet, and
very massive black hole provides a unique opportunity to investigate the origin
of very high energy (VHE; E>100 GeV) gamma-ray emission generated in
relativistic outflows and the surroundings of super-massive black holes. M 87
has been established as a VHE gamma-ray emitter since 2006. The VHE gamma-ray
emission displays strong variability on timescales as short as a day. In this
paper, results from a joint VHE monitoring campaign on M 87 by the MAGIC and
VERITAS instruments in 2010 are reported. During the campaign, a flare at VHE
was detected triggering further observations at VHE (H.E.S.S.), X-rays
(Chandra), and radio (43 GHz VLBA). The excellent sampling of the VHE gamma-ray
light curve enables one to derive a precise temporal characterization of the
flare: the single, isolated flare is well described by a two-sided exponential
function with significantly different flux rise and decay times. While the
overall variability pattern of the 2010 flare appears somewhat different from
that of previous VHE flares in 2005 and 2008, they share very similar
timescales (~day), peak fluxes (Phi(>0.35 TeV) ~= (1-3) x 10^-11 ph cm^-2
s^-1), and VHE spectra. 43 GHz VLBA radio observations of the inner jet regions
indicate no enhanced flux in 2010 in contrast to observations in 2008, where an
increase of the radio flux of the innermost core regions coincided with a VHE
flare. On the other hand, Chandra X-ray observations taken ~3 days after the
peak of the VHE gamma-ray emission reveal an enhanced flux from the core. The
long-term (2001-2010) multi-wavelength light curve of M 87, spanning from radio
to VHE and including data from HST, LT, VLA and EVN, is used to further
investigate the origin of the VHE gamma-ray emission. No unique, common MWL
signature of the three VHE flares has been identified.Comment: 19 pages, 5 figures; Corresponding authors: M. Raue, L. Stawarz, D.
Mazin, P. Colin, C. M. Hui, M. Beilicke; Fig. 1 lightcurve data available
online: http://www.desy.de/~mraue/m87
Legitimacy intermediation in the multilevel European polity and its collapse in the euro crisis
This essay re-examines the dual – republican and liberal – foundations of democratic legitimacy in the Western traditions of normative political theory. Considered in isolation, the European Union conforms to liberal standards but cannot satisfy republican criteria. Given these conflicting standards, debates on the alleged European democratic deficit have remained inconclusive. Moreover, they have failed to pay sufficient attention to the multilevel character of the European polity and to the normative potential of legitimacy intermediation in its two-step compliance and legitimating relationships. I argue, however, that the capacity of democratic member states to legitimate the exercise of European governing functions is being destroyed in the present euro crisis, and I briefly discuss the implications of this new constellation.In der westlichen Tradition der normativen politischen Theorie beruht demokratische Legitimität auf der doppelten Grundlage republikanischer und liberaler Prinzipien. Für sich betrachtet entspricht die Europäische Union zwar liberalen Kriterien, aber eben nicht den republikanischen Anforderungen. Angesichts so unterschiedlicher Kriterien konnte es auch im Streit über das angebliche europäische Demokratiedefizit keine Einigung geben. Überdies ignorierte diese Diskussion den Mehrebenen-Charakter der europäischen Politik und das normative Potenzial der Legitimationsvermittlung zwischen Union und Bürgern durch die demokratisch verfassten Mitgliedstaaten. Die gegenwärtige Eurokrise allerdings zerstört die Fähigkeit demokratischer Mitgliedstaaten, die Ausübung europäischer Herrschaftsfunktionen zu legitimieren. Der Aufsatz erörtert die Implikationen dieser neuen Konstellation.1 Introduction 2 Legitimacy discourses The republican discourse The liberal discourse Differences 3 Constitutional democracies – and the European Union? 4 Legitimacy intermediation in the multilevel European polity 5 The end of legitimacy intermediation in the euro crisis Monetary Union and the failure of output legitimacy Rescuing the euro through supranational intervention 6 Legitimate supranational government? Input-oriented European legitimacy? 7 Reducing the burden on European legitimacy Reference
Predicting risky drinking: is demoralization running up the tab?
Access to thesis permanently restricted to Ball State community only.College students frequently engage in patterns of problematic drinking which are
associated with negative consequences (Osberg et al., 2010). However, intervention strategies
have been shown to be ineffective (Henson et al., 2015). Prediction models include
environmental factors, drinking motives, disinhibition, and negative affectivity with evidence
suggesting that demoralization may be a factor (Moser et al., 2014). Thus, the current study
examined if demoralization explained additional variance in problematic drinking not captured
by current models. Participants were 334 midwestern college students (MAge = 18.8, SDage = 1.27,
72.2% women, 84.4% White) who completed measures of the aforementioned risk factors,
demographics, and various drinking behaviors. Results of a linear regression, R2 = .42, indicated
that disinhibition, = .35, coping motives, = .26, and enhancement motives, = .15, predicted
disordered drinking. Results of a logistic regression indicated that coping motives, Exp B = 1.19,
enhancement motives, Exp B = 1.16, and disinhibition, Exp B = 1.15, predicted binge drinking,
Cox & Snell Pseudo R2 = .22. Coping motives, Exp B = 1.29, and enhancement motives, Exp B =
1.24, predicted risky drinking, Cox & Snell Pseudo R2 = .15. Disinhibition, Exp B = 1.11, and
enhancement motives, Exp B = .91, predicted early onset drinking. Demoralization was not a
significant predictor of problematic drinking. Results replicate past research supporting
disinhibition, enhancement motives, and coping motives as robust predictors of problematic
drinking (Sayette, 2017). However, support for other risk factors was not replicated. Findings
suggest that patterns of problematic drinking may have distinct predictors. Further, the
replication of disinhibition, enhancement motives, and coping motives implies that future
research should examine if providing examples of adaptive reward and sensation seeking
behaviors, and emotion regulation strategies could help to increase treatment efficacy.
Limitations and future directions are discussed.Thesis (M.S.
An Economic Anatomy of Optimal Climate Policy
This paper introduces geoengineering into an optimal control model of climate change economics. Together with mitigation and adaptation, carbon and solar geoengineering span the universe of possible climate policies. Their wildly different characteristics have important implications for climate policy. We show in the context of our model that: (i) the optimal carbon tax equals the marginal cost of carbon geoengineering; (ii) the introduction of either form of geoengineering leads to higher emissions yet lower temperatures; (iii) in a world with above-optimal cumulative emissions, only a complete set of instruments can minimize climate damages