Strong support for the millisecond pulsar origin of the Galactic center GeV excess

Using gamma-ray data from the Fermi Large Area Telescope, various groups have identified a clear excess emission in the Inner Galaxy, at energies around a few GeV. This excess resembles remarkably well a signal from dark-matter annihilation. One of the most compelling astrophysical interpretations is that the excess is caused by the combined effect of a previously undetected population of dim gamma-ray sources. Because of their spectral similarity, the best candidates are millisecond pulsars. Here, we search for this hypothetical source population, using a novel approach based on wavelet decomposition of the gamma-ray sky and the statistics of Gaussian random fields. Using almost seven years of Fermi-LAT data, we detect a clustering of photons as predicted for the hypothetical population of millisecond pulsar, with a statistical significance of 10.0 sigma. For plausible values of the luminosity function, this population explains 100% of the observed excess emission. We argue that other extragalactic or Galactic sources, a mismodeling of Galactic diffuse emission, or the thick-disk population of pulsars are unlikely to account for this observation.Comment: 6+10 pages, 3+10 figures, 1 table; v2 updated to pass 8 Fermi data, additional supplemental material with extended discussion (conclusions unchanged); v3 matches PRL version with further checks (conclusions unchanged

Measurement of radiative neutralino production

We perform the first experimental study with full detector simulation for the radiative production of neutralinos at the linear collider, at sqrt{s} = 500 GeV and realistic beam polarizations. We consider all relevant backgrounds, like the Standard Model background from radiative neutrino production. The longitudinal polarized beams enhance the signal and simultaneously reduce the background, such that statistical errors are significantly reduced. We find that the photon spectrum from the signal process can be well isolated. The neutralino mass and the cross section can be measured at a few per-cent level, with the largest systematic uncertainties from the measurement of the beam polarization and the beam energy spectrum.Comment: 6 pages, 2 figures, to appear in the proceedings of the 2011 International Workshop on Future Linear Colliders (LCWS11), Sept. 26-30, Granada, Spai

Robust a priori and a posteriori error analysis for the approximation of Allen–Cahn and Ginzburg–Landau equations past topological changes

A priori and a posteriori error estimates are derived for the numerical approximation of scalar and complex valued phase field models. Particular attention is devoted to the dependence of the estimates on a small parameter and to the validity of the estimates in the presence of topological changes in the solution that represents singular points in the evolution. For typical singularities the estimates depend on the inverse of the parameter in a polynomial as opposed to exponential dependence of estimates resulting from a straightforward error analysis. The estimates naturally lead to adaptive mesh refinement and coarsening algorithms. Numerical experiments illustrate the reliability and efficiency of this approach for the evolution of interfaces and vortices that undergo topological changes

Model-independent WIMP Characterisation using ISR

The prospects of measuring the parameters of WIMP dark matter in a model independent way at the International Linear Collider are investigated. The signal under study is direct WIMP pair production with associated initial state radiation. The analysis is performed in full simulation of the ILD detector concept. With an integrated luminosity of L = 500 fb-1 and realistic beam polarizations the helicity structure of the WIMP couplings to electrons can be determined, and the masses and cross sections can be measured to the percent level. The systematic uncertainties are dominated by the polarization measurement and the luminosity spectrum.Comment: 7 pages, 4 figures, International Workshop on Future Linear Colliders LCWS1

International recommendations for outpatient palliative care and prehospital palliative emergencies - a prospective questionnaire-based investigation

BACKGROUND: To determine the international recommendations and current practices for the treatment and prevention of palliative emergencies. The primary goal of the study was to gather information from experts on their nationally practised concepts. METHODS: One hundred and fifty self-report surveys were distributed by email to selected leading experts (palliative and emergency medical care) in Europe, North and South America, Africa, Asia, and Australia. An expert in this context was defined as an author of an article that was ranked by three reviewers as relevant to outpatient palliative and emergency medical . RESULTS: The total response rate was 61% (n = 92 experts). Survey responses were obtained from 35 different countries. The following standards in the treatment of palliative emergencies were recommended: (1) early integration of "Palliative Care Teams" (PCTs) and basic outpatient palliative care systems, (2) end-of-life discussions, (3) defined emergency medical documents, drug boxes, and "Do not attempt resuscitation" orders and (4) emergency medical training (physicians and paramedics). CONCLUSIONS: This study detected structurally and nationally differences in outpatient palliative care regarding the treatment of palliative emergencies. Accordingly, these differences should be discussed and adapted to the respective specifications of individual single countries. A single established outpatient palliative emergency medical care concept may be the basis for an overall out-of-hospital palliative care system

Cavity Enhanced Optical Vernier Spectroscopy, Broad Band, High Resolution, High Sensitivity

A femtosecond frequency comb provides a vast number of equidistantly spaced narrow band laser modes that can be simultaneously tuned and frequency calibrated with 15 digits accuracy. Our Vernier spectrometer utilizes all of theses modes in a massively parallel manner to rapidly record both absorption and dispersion spectra with a sensitivity that is provided by a high finesse broad band optical resonator and a resolution that is only limited by the frequency comb line width while keeping the required setup simple.Comment: 11 pages, 3 figures, submitted to PR

The average laboratory samples a population of 7,300 Amazon Mechanical Turk workers

Using capture-recapture analysis we estimate the effective size of the active Amazon Mechanical Turk (MTurk) population that a typical laboratory can access to be about 7,300 workers. We also estimate that the time taken for half of the workers to leave the MTurk pool and be replaced is about 7 months. Each laboratory has its own population pool which overlaps, often extensively, with the hundreds of other laboratories using MTurk. Our estimate is based on a sample of 114,460 completed sessions from 33,408 unique participants and 689 sessions across seven laboratories in the US, Europe, and Australia from January 2012 to March 2015

Characterising WIMPs at a future e+e−e^+e^- Linear Collider

We investigate the prospects for detecting and measuring the parameters of WIMP dark matter in a model independent way at the International Linear Collider. The signal under study is direct WIMP pair production with associated initial state radiation $e^+e^- \rightarrow \chi\chi\gamma$. The analysis accounts for the beam energy spectrum of the ILC and the dominant machine induced backgrounds. The influence of the detector parameters are incorporated by full simulation and event reconstruction within the framework of the ILD detector concept. We show that by using polarised beams, the detection potential is significantly increased by reduction of the dominant SM background of radiative neutrino production $e^+e^- \rightarrow \nu\nu\gamma$. The dominant sources of systematic uncertainty are the precision of the polarisation measurement and the shape of the beam energy spectrum. With an integrated luminosity of 500 fb the helicity structure of the interaction involved can be inferred, and the masses and cross-sections can be measured with a relative accuracy of the order of 1 %.Comment: 20 pages, 11 figure