Search Publications
Ensemble Prediction of a Halo Coronal Mass Ejection Using Heliospheric Imagers
Möstl, C.; Temmer, M.; Amerstorfer, T. +5 more
The Solar TErrestrial RElations Observatory (STEREO) and its heliospheric imagers (HIs) have provided us the possibility to enhance our understanding of the interplanetary propagation of coronal mass ejections (CMEs). HI-based methods are able to forecast arrival times and speeds at any target and use the advantage of tracing a CME's path of propa…
Distances from the tip of the red giant branch to the dwarf galaxies dw1335-29 and dw1340-30 in the Centaurus group
Müller, Oliver; Jerjen, Helmut; Rejkuba, Marina
Context. The abundance and spatial distribution of dwarf galaxies are excellent empirical benchmarks against which to test models of structure formation on small scales. The nearby Centaurus group, with its two subgroups centered on Cen A and M 83, stands out as an important alternative to the Local Group for scrutinizing cosmological model predic…
Dark matter dynamics in Abell 3827: new data consistent with standard cold dark matter
Richard, Johan; Massey, Richard; Smit, Renske +23 more
We present integral field spectroscopy of galaxy cluster Abell 3827, using Atacama Large Millimetre Array (ALMA) and Very Large Telescope/Multi-Unit Spectroscopic Explorer. It reveals an unusual configuration of strong gravitational lensing in the cluster core, with at least seven lensed images of a single background spiral galaxy. Lens modelling …
Multi-wavelength campaign on NCG 7469. IV. The broad-band X-ray spectrum
Kriss, G. A.; Arav, N.; Bianchi, S. +17 more
We conducted a multi-wavelength 6-month campaign to observe the Seyfert Galaxy NGC 7469, using the space-based observatories HST, Swift, XMM-Newton and NuSTAR. We report the results of the spectral analysis of the seven simultaneous XMM-Newton and NuSTAR observations. The source shows significant flux variability within each observation, but the a…
Energetic Ion Moments and Polytropic Index in Saturn's Magnetosphere using Cassini/MIMI Measurements: A Simple Model Based on κ-Distribution Functions
Krupp, Norbert; Krimigis, Stamatios M.; Mitchell, Donald G. +7 more
Moments of the charged particle distribution function provide a compact way of studying the transport, acceleration, and interactions of plasma and energetic particles in the magnetosphere. We employ κ-distributions to describe the energy spectra of H+ and O+, based on >20 keV measurements by the three detectors of Cassini…
Abundance of SiC2 in carbon star envelopes
Alcolea, J.; Cernicharo, J.; Goicoechea, J. R. +6 more
Context. Silicon carbide dust is ubiquitous in circumstellar envelopes around C-rich asymptotic giant branch (AGB) stars. However, the main gas-phase precursors leading to the formation of SiC dust have not yet been identified. The most obvious candidates among the molecules containing an Si-C bond detected in C-rich AGB stars are SiC2,…
An updated stellar census of the Quintuplet cluster
Najarro, F.; Clark, J. S.; Dong, H. +3 more
Context. Found within the central molecular zone, the Quintuplet is one of the most massive young clusters in the Galaxy. As a consequence it offers the prospect of constraining stellar formation and evolution in extreme environments. However, current observations suggest that it comprises a remarkably diverse stellar population that is difficult …
Planetary Period Oscillations in Saturn's Magnetosphere: Cassini Magnetic Field Observations Over the Northern Summer Solstice Interval
Dougherty, M. K.; Cowley, S. W. H.; Bunce, E. J. +3 more
We determine properties of Saturn's planetary period oscillations from Cassini magnetic measurements over the 2-year interval from September 2015 to end of mission in September 2017, spanning Saturn northern summer solstice in May 2017. Phases of the northern system oscillations are derived over the whole interval, while those of the southern syst…
Glimpses of the past activity of Sgr A★ inferred from X-ray echoes in Sgr C
Ponti, G.; Morris, M. R.; Terrier, R. +6 more
Context. For a decade now, evidence has accumulated that giant molecular clouds located within the central molecular zone of our Galaxy reflect X-rays coming from past outbursts of the Galactic supermassive black hole. However, the number of illuminating events as well as their ages and durations are still unresolved questions.
Aims: We aim t…
A search for new supernova remnant shells in the Galactic plane with H.E.S.S.
Klochkov, D.; Santangelo, A.; Quirrenbach, A. +262 more
A search for new supernova remnants (SNRs) has been conducted using TeV γ-ray data from the H.E.S.S. Galactic plane survey. As an identification criterion, shell morphologies that are characteristic for known resolved TeV SNRs have been used. Three new SNR candidates were identified in the H.E.S.S. data set with this method. Extensive multiwavelen…