Search Publications
Hα features with hot onsets. I. Ellerman bombs
Rutten, R. J.
Ellerman bombs are transient brightenings of the wings of the Balmer lines that uniquely mark reconnection in the solar photosphere. They are also bright in strong Ca II and ultraviolet lines and in ultraviolet continua, but they are not visible in the optical continuum and the Na I D and Mg I b lines. These discordant visibilities invalidate all …
Planck intermediate results. XLIV. Structure of the Galactic magnetic field from dust polarization maps of the southern Galactic cap
Miville-Deschênes, M. -A.; Boulanger, F.; Bernard, J. -P. +165 more
Using data from the Planck satellite, we study the statistical properties of interstellar dust polarization at high Galactic latitudes around the south pole (b < -60°). Our aim is to advance the understanding of the magnetized interstellar medium (ISM), and to provide a modelling framework of the polarized dust foreground for use in cosmic micr…
Dust attenuation in z ~ 1 galaxies from Herschel and 3D-HST Hα measurements
Berta, S.; Lutz, D.; Cimatti, A. +12 more
We combined the spectroscopic information from the 3D-HST survey with Herschel data to characterize the Hα dust attenuation properties of a sample of 79 main sequence star-forming galaxies at z ~ 1 in the GOODS-S field. The sample was selected in the far-IR at λ = 100 and/or 160 µm and only includes galaxies with a secure Hα detection (S/N &…
Reconnection brightenings in the quiet solar photosphere
Rouppe van der Voort, Luc H. M.; Rutten, Robert J.; Vissers, Gregal J. M.
We describe a new quiet-Sun phenomenon which we call quiet-Sun Ellerman-like brightenings (QSEB). QSEBs are similar to Ellerman bombs (EB) in some respects but differ significantly in others. EBs are transient brightenings of the wings of the Balmer Hα line that mark strong-field photospheric reconnection in complex active regions. QSEBs are simil…
Gamma rays detected from Cygnus X-1 with likely jet origin
Aharonian, F.; Blanch, O.; de Oña Wilhelmi, E. +4 more
Aims: We probe the high-energy (>60 MeV) emission from the black hole X-ray binary system, Cygnus X-1, and investigate its origin.
Methods: We analyzed 7.5 yr of data by Fermi-LAT with the latest Pass 8 software version.
Results: We report the detection of a signal at 8σ statistical significance that is spatially coincident with …
Sunset jets observed on comet 67P/Churyumov-Gerasimenko sustained by subsurface thermal lag
Jorda, L.; Lamy, P. L.; Lara, L. M. +46 more
We present observations of sunset jets on comet 67P/Churyumov-Gerasimenko by Rosetta/OSIRIS camera. In late April 2015, when the comet was at a heliocentric distance of ~1.8 AU, clusters of dust jets that originated in the Ma'at region on the comet's small lobe were identified from multipleimages and were apparently sustained for about an hour bey…
First detection of gas-phase ammonia in a planet-forming disk. NH3, N2H+, and H2O in the disk around TW Hydrae
Cleeves, L. Ilsedore; Bergin, Edwin A.; van Dishoeck, Ewine F. +10 more
Context. Nitrogen chemistry in protoplanetary disks and the freeze-out on dust particles is key for understanding the formation of nitrogen-bearing species in early solar system analogs. In dense cores, 10% to 20% of the nitrogen reservoir is locked up in ices such as NH3, NH4+ and OCN-. So far, ammonia …
Planck 2015 results. IV. Low Frequency Instrument beams and window functions
Bernard, J. -P.; Planck Collaboration; Ade, P. A. R. +200 more
This paper presents the characterization of the in-flight beams, the beam window functions, and the associated uncertainties for the Planck Low Frequency Instrument (LFI). The structure of the paper is similar to that presented in the 2013 Planck release; the main differences concern the beam normalization and the delivery of the window functions …
Planck intermediate results. XXXIX. The Planck list of high-redshift source candidates
Kneissl, R.; Miville-Deschênes, M. -A.; Boulanger, F. +188 more
The Planck mission, thanks to its large frequency range and all-sky coverage, has a unique potential for systematically detecting the brightest, and rarest, submillimetre sources on the sky, including distant objects in the high-redshift Universe traced by their dust emission. A novel method, based on a component-separation procedure using a combi…
Another piece of the puzzle: The fast H I outflow in Mrk 231
Veilleux, Sylvain; Morganti, Raffaella; Oosterloo, Tom +2 more
We present the detection, performed with the Westerbork Synthesis Radio Telescope (WSRT) and the Karl Jansky Very Large Array (VLA), of a fast H I 21 cm outflow in the ultra-luminous infrared galaxy Mrk 231. The outflow is observed as shallow H I absorption blueshifted ~1300 km s-1 with respect to the systemic velocity and located again…