Governments, Informal Links to Militias and Accountability

From Syria to Sudan, governments have informal ties with militias that use violence against opposition groups and civilians. Building on research that suggests these groups offer governments logistical benefits in civil wars as well as political benefits in the form of reduced liability for violence, we provide the first systematic global analysis of the scale and patterns of these informal linkages. We find over 200 informal state–militia relationships across the globe, within but also outside of civil wars. We illustrate how informal delegation of violence to these groups can help some governments avoid accountability for violence and repression. Our empirical analysis finds that weak democracies as well as recipients of financial aid from democracies are particularly likely to form informal ties with militias. This relationship is strengthened as the monitoring costs of democratic donors increase. Out-of-sample predictions illustrate the usefulness of our approach that views informal ties to militias as deliberate government strategy to avoid accountability

Measurement of Coherent Elastic Neutrino-Nucleus Scattering from reactor antineutrinos

The 96.4 day exposure of a 3 kg ultra-low noise germanium detector to the high flux of antineutrinos from a power nuclear reactor is described. A very strong preference ($p<1.2\times10^{-3}$) for the presence of a coherent elastic neutrino-nucleus scattering (CE$\nu$NS) component in the data is found, when compared to a background-only model. No such effect is visible in 25 days of operation during reactor outages. The best-fit CE$\nu$NS signal is in good agreement with expectations based on a recent characterization of germanium response to sub-keV nuclear recoils. Deviations of order 60\% from the Standard Model CE$\nu$NS prediction can be excluded using present data. Standing uncertainties in models of germanium quenching factor, neutrino energy spectrum, and background are examined.Comment: 6 pages, 5 figures. Data release and additional information in ancillary file

Experimental constraints on a dark matter origin for the DAMA annual modulation effect

A claim for evidence of dark matter interactions in the DAMA experiment has been recently reinforced. We employ a new type of germanium detector to conclusively rule out a standard isothermal galactic halo of Weakly Interacting Massive Particles (WIMPs) as the explanation for the annual modulation effect leading to the claim. Bounds are similarly imposed on a suggestion that dark pseudoscalars mightlead to the effect. We describe the sensitivity to light dark matter particles achievable with our device, in particular to Next-to-Minimal Supersymmetric Model candidates.Comment: v4: introduces recent results from arXiv:0807.3279 and arXiv:0807.2926. Sensitivity to pseudoscalars is revised in light of the first. Discussion on the subject adde

Results from a Search for Light-Mass Dark Matter with a P-type Point Contact Germanium Detector

We report on several features present in the energy spectrum from an ultra low-noise germanium detector operated at 2,100 m.w.e. By implementing a new technique able to reject surface events, a number of cosmogenic peaks can be observed for the first time. We discuss several possible causes for an irreducible excess of bulk-like events below 3 keVee, including a dark matter candidate common to the DAMA/LIBRA annual modulation effect, the hint of a signal in CDMS, and phenomenological predictions. Improved constraints are placed on a cosmological origin for the DAMA/LIBRA effect.Comment: 4 pages, 4 figures. v2: submitted version. Minimal changes in wording, one reference adde

Search for an Annual Modulation in a P-type Point Contact Germanium Dark Matter Detector

Fifteen months of cumulative CoGeNT data are examined for indications of an annual modulation, a predicted signature of Weakly Interacting Massive Particle (WIMP) interactions. Presently available data support the presence of a modulated component of unknown origin, with parameters prima facie compatible with a galactic halo composed of light-mass WIMPs. Unoptimized estimators yield a statistical significance for a modulation of ~2.8 sigma, limited by the short exposure.Comment: Published version, slightly expanded discussion of ROI uncertainties, one reference adde

Characterisation of a small electrode HPGe detector

© 2019 Elsevier B.V. Small electrode HPGe detectors in an inverted coaxial geometry are increasingly in use in applications where both high efficiency and excellent energy resolution are required. The unusual electric field configuration of these detectors results in extremely long charge collection times compared to planar and coaxial devices. In this work we have characterised such a detector using gamma-ray coincidence measurements and optimised an electric field simulation to reproduce the positional variation of detector response. We show that, alongside accurate crystal geometry and applied electric potential, a temperature correction is crucial to correctly determining appropriate charge carrier mobility parameters. This work will help to guide the future development of HPGE detectors for applications including radioactive waste assay, radio-isotope dating, and fundamental nuclear physics

Institutional trustworthiness and national security governance:Evidence from six European countries

[EN] This article examines the relationship between the institutional trustworthiness of security agencies in the context of data¿intensive security practices. It focuses on the public's acceptance of the way digital surveillance technologies feed into large¿scale security data analytics. Using the case of deep packet inspection (DPI), survey data gathered in six European countries (n¿=¿1,202) demonstrates that security agencies' institutional trustworthiness directly and indirectly influences public acceptance of DPI. Against a backdrop of declining public trust in government and a climate of intense international terrorist threat, governments around the world are appealing to citizens to trade privacy for enhanced security. This article supports calls for security agencies and their respective governments to engage with the democratic process to enrich security and privacy at all levels of public security governance and for the common good