Publications (24)
Cosmic ray transport in galaxy clusters: implications for radio halos and gamma-rays
Christoph Pfrommer, Torsten Ensslin, Francesco Miniati +1
Observations of giant radio halos provide unambiguous evidence for the existence of cosmic ray (CR) electrons and magnetic fields in galaxy clusters. The physical mechanism generat…
Signatures of Magnetized Large Scale Structure in Ultra-High Energy Cosmic Rays
Guenter Sigl, Francesco Miniati, Torsten Ensslin
We investigate the impact of a structured universe in the multi-pole moments, auto-correlation function, and cluster statistics of cosmic rays above 10^19 eV. We compare structured…
A 3D View of Orion: I. Barnard's Loop
Michael M. Foley, Alyssa Goodman, Catherine Zucker +11
Barnard's Loop is a famous arc of H emission located in the Orion star-forming region. Here, we provide evidence of a possible formation mechanism for Barnard's Loop and compar…
Efficient cosmological parameter sampling using sparse grids
Mona Frommert, Dirk Pflueger, Thomas Riller +3
We present a novel method to significantly speed up cosmological parameter sampling. The method relies on constructing an interpolation of the CMB-log-likelihood based on sparse gr…
A New Method for Analysing Dark Matter Direct Detection Data
Jonathan H. Davis, Torsten Ensslin, Celine Boehm
The experimental situation of Dark Matter Direct Detection has reached an exciting cross-roads, with potential hints of a discovery of Dark Matter (DM) from the CDMS, CoGeNT, CRESS…
Ultra-High Energy Cosmic Rays in a Structured and Magnetized Universe
Guenter Sigl, Francesco Miniati, Torsten Ensslin
We simulate propagation of cosmic ray nucleons above 10^{19} eV in scenarios where both the source distribution and magnetic fields within about 50 Mpc from us are obtained from an…
Ultra-High Energy Cosmic Ray Probes of Large Scale Structure and Magnetic Fields
Guenter Sigl, Francesco Miniati, Torsten Ensslin
We study signatures of a structured universe in the multi-pole moments, auto-correlation function, and cluster statistics of ultra-high energy cosmic rays above 10^19 eV. We compar…
Exploring the MeV Sky with a Combined Coded Mask and Compton Telescope: The Galactic Explorer with a Coded Aperture Mask Compton Telescope (GECCO)
Elena Orlando, Eugenio Bottacini, Alexander Moiseev +33
The sky at MeV energies is currently poorly explored. Here we present an innovative mission concept that builds on and improves past and currently proposed missions at such energie…
Theia: Faint objects in motion or the new astrometry frontier
The Theia Collaboration, Celine Boehm, Alberto Krone-Martins +96
In the context of the ESA M5 (medium mission) call we proposed a new satellite mission, Theia, based on relative astrometry and extreme precision to study the motion of very faint…
Cosmic Magnetic Fields and Their Influence on Ultra-High Energy Cosmic Ray Propagation
Guenter Sigl, Francesco Miniati, Torsten Ensslin
We discuss the influence of large scale cosmic magnetic fields on the propagation of hadronic cosmic rays above 10^19 eV based on large scale structure simulations. Our simulations…
A simulation pipeline for the Planck mission
Martin Reinecke, Klaus Dolag, Reinhard Hell +2
We describe an assembly of numerical tools to model the output data of the Planck satellite. These start with the generation of a CMB sky in a chosen cosmology, add in various fore…
The XENON100 exclusion limit without considering Leff as a nuisance parameter
Jonathan H Davis, Celine Boehm, Niels Oppermann +2
In 2011, the XENON100 experiment has set unprecedented constraints on dark matter-nucleon interactions, excluding dark matter candidates with masses down to 6 GeV if the correspond…
Reconstruction of signals with unknown spectra in information field theory with parameter uncertainty
Torsten Ensslin, Mona Frommert
The optimal reconstruction of cosmic metric perturbations and other signals requires knowledge of their power spectra and other parameters. If these are not known a priori, they ha…
Statistical methods for the analysis of rotation measure grids in large scale structures in the SKA era
Valentina Vacca, Niels Oppermann, Torsten Ensslin +18
To better understand the origin and properties of cosmological magnetic fields, a detailed knowledge of magnetic fields in the large-scale structure of the Universe (galaxy cluster…
Extragalactic Cosmic Rays and Magnetic Fields: Facts and Fiction
Torsten Ensslin
A critical discussion of our knowledge about extragalactic cosmic rays and magnetic fields is attempted. What do we know for sure? What are our prejudices? How do we confront our m…
Radio observations of the Galactic Centre and the Coma cluster as a probe of light dark matter self-annihilations and decay
Celine Boehm, Joseph Silk, Torsten Ensslin
We update our earlier calculations of gamma ray and radio observational constraints on annihilations of dark matter particles lighter than 10 GeV. We predict the synchrotron spectr…
Galaxy cluster merger kinematics by Rees-Sciama effect
Matteo Maturi, Torsten Ensslin, Carlos Hernandez-Monteagudo +1
We discuss how to use the Rees-Sciama (RS) effect associated with merging clusters of galaxies to measure their kinematic properties. In a previous work (Rubino-Martin et al. 2004)…
A Wideband Polarization Observation of Hydra A with the Jansky Very Large Array
Lerato Baidoo, Richard A. Perley, Jean Eilek +3
We present results of a wideband high-resolution polarization study of Hydra A, one of the most luminous FR I radio galaxies known and amongst the most well-studied. The radio emis…
Bayesian analysis of spatially distorted cosmic signals from Poissonian data
Cornelius Weig, Torsten Ensslin
Reconstructing the matter density field from galaxy counts is a problem frequently addressed in current literature. Two main sources of error are shot noise from galaxy counts and…
Magnetic fields and cosmic rays in cooling flows
Torsten Ensslin, Corina Vogt, Christoph Pfrommer
Cooling flows are regions where the importance of non-thermal intra-cluster medium components such as magnetic fields and cosmic rays may be strongest within a galaxy cluster. They…
Magnetic Field Seeding by Galactic Winds
Serena Bertone, Corina Vogt, Torsten Ensslin
The origin of intergalactic magnetic fields is still a mystery and several scenarios have been proposed so far: among them, primordial phase transitions, structure formation shocks…
Spectral study of the diffuse synchrotron source in the galaxy cluster Abell 523
Valentina Vacca, Timothy Shimwell, Richard A. Perley +26
The galaxy cluster Abell 523 (A523) hosts an extended diffuse synchrotron source historically classified as a radio halo. Its radio power at 1.4 GHz makes it one of the most signif…
IMAGINE: A comprehensive view of the interstellar medium, Galactic magnetic fields and cosmic rays
Francois Boulanger, Torsten Ensslin, Andrew Fletcher +20
In this white paper we introduce the IMAGINE Consortium and its scientific background, goals and structure. Our purpose is to coordinate and facilitate the efforts of a diverse gro…
AstroGrid-D: Grid Technology for Astronomical Science
Harry Enke, Matthias Steinmetz, Hans-Martin Adorf +16
We present status and results of AstroGrid-D, a joint effort of astrophysicists and computer scientists to employ grid technology for scientific applications. AstroGrid-D provides…