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Planck intermediate results. XIV. Dust emission at millimetre wavelengths in the Galactic plane
Kneissl, R.; Miville-Deschênes, M. -A.; Boulanger, F. +192 more
We use Planck HFI data combined with ancillary radio data to study the emissivity index of the interstellar dust emission in the frequency range 100-353 GHz, or 3-0.8 mm, in the Galactic plane. We analyse the region l = 20°-44° and |b| ≤ 4° where the free-free emission can be estimated from radio recombination line data. We fit the spectra at each…
Hubble Space Telescope/Cosmic Origins Spectrograph Observations of the Quasar Q0302-003: Probing the He II Reionization Epoch and QSO Proximity Effects
Shull, J. Michael; Syphers, David
Q0302-003 (z = 3.2860 ± 0.0005) was the first quasar discovered that showed a He II Gunn-Peterson trough, a sign of incomplete helium reionization at z >~ 2.9. We present its Hubble Space Telescope/Cosmic Origins Spectrograph far-UV medium-resolution spectrum, which resolves many spectral features for the first time, allowing study of the quasa…
CLASH-VLT: The stellar mass function and stellar mass density profile of the z = 0.44 cluster of galaxies MACS J1206.2-0847
Demarco, R.; Infante, L.; Grillo, C. +29 more
Context. The study of the galaxy stellar mass function (SMF) in relation to the galaxy environment and the stellar mass density profile, ρ⋆(r), is a powerful tool to constrain models of galaxy evolution.
Aims: We determine the SMF of the z = 0.44 cluster of galaxies MACS J1206.2-0847 separately for passive and star-forming (SF) gal…
The particle content of low-power radio galaxies in groups and clusters
Hardcastle, M. J.; Croston, J. H.
The synchrotron-radiating particles and magnetic fields in low-power radio galaxies (including most nearby cluster-centre sources), if at equipartition, can provide only a small fraction of the total internal energy density of the radio lobes or plumes, which is now well constrained via X-ray observations of their external environments. We conside…
Observation of large-amplitude magnetosonic waves at dipolarization fronts
Nishimura, Yukitoshi; Yuan, Zhigang; Huang, Shiyong +6 more
Various plasma waves have been observed in the vicinity of dipolarization fronts (DFs) and the rarefaction regions behind them. It was suggested that these waves not only play crucial roles in regulating particle kinetics at the DFs but also may potentially affect the large-scale dynamics of the magnetotail. In this paper, we present the observati…
The Very Faint End of the UV Luminosity Function over Cosmic Time: Constraints from the Local Group Fossil Record
Conroy, Charlie; Johnson, Benjamin D.; Weisz, Daniel R.
We present a new technique to estimate the evolution of the very faint end of the UV luminosity function (LF) out to z ~ 5. Measured star formation histories (SFHs) from the fossil record of Local Group (LG) galaxies are used to reconstruct the LF down to M UV ~-5 at z ~ 5 and M UV ~-1.5 at z < 1. Such faint limits are wel…
Plasma environment of a weak comet - Predictions for Comet 67P/Churyumov-Gerasimenko from multifluid-MHD and Hybrid models
Altwegg, K.; Glassmeier, K. -H.; Richter, I. +8 more
The interaction of a comet with the solar wind undergoes various stages as the comet's activity varies along its orbit. For a comet like 67P/Churyumov-Gerasimenko, the target comet of ESA's Rosetta mission, the various features include the formation of a Mach cone, the bow shock, and close to perihelion even a diamagnetic cavity. There are differe…
On the formation of Mg ii h and k lines in solar prominences
Heinzel, P.; Vial, J. -C.; Anzer, U.
Aims: With the recent launch of the IRIS mission, it has become urgent to develop the spectral diagnostics using the Mg ii resonance h and k lines. In this paper, we aim to demonstrate the behavior of these lines under various prominence conditions. Our results serve as a basis for analysis of new IRIS data and for more sophisticated prominen…
Wave-particle interactions during a dipolarization front event
Goldstein, M. L.; Hwang, K. -J.; F. -Viñas, A. +2 more
We present Cluster observations of wave-particle interactions during an earthward propagating dipolarization front (DF) and associated fast plasma bulk flows detected at the central current sheet in Earth's magnetotail. During this period, flux tubes behind the DF frequently contain more energetic or hotter ions than did the preexisting flux tubes…
Direct Observations of Magnetic Flux Rope Formation during a Solar Coronal Mass Ejection
Chen, Y.; Song, H. Q.; Cheng, X. +1 more
Coronal mass ejections (CMEs) are the most spectacular eruptive phenomena in the solar atmosphere. It is generally accepted that CMEs are the results of eruptions of magnetic flux ropes (MFRs). However, there is heated debate on whether MFRs exist prior to the eruptions or if they are formed during the eruptions. Several coronal signatures, e.g., …