Search Publications
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…
Herschel-Planck dust optical depth and column density maps. II. Perseus
Alves, João; Bouy, Hervé; Lada, Charles J. +2 more
We present optical depth and temperature maps of the Perseus molecular cloud, obtained combining dust emission data from the Herschel and Planck satellites and 2MASS/NIR dust extinction maps. The maps have a resolution of 36 arcsec in the Herschel regions, and of 5 arcmin elsewhere. The dynamic range of the optical depth map ranges from 1 × 10
Constraints on the location of a possible 9th planet derived from the Cassini data
Laskar, J.; Fienga, A.; Manche, H. +1 more
To explain the unusual distribution of Kuiper belt objects, several authors have advocated the existence of a super-Earth planet in the outer solar system. It has recently been proposed that a 10 M⊕ object with an orbit of 700 AU semi major axis and 0.6 eccentricity can explain the observed distribution of Kuiper belt objects around Sed…
The XMM Cluster Outskirts Project (X-COP): Physical conditions of Abell 2142 up to the virial radius
Hurier, G.; Pointecouteau, E.; Rossetti, M. +9 more
Context. Galaxy clusters are continuously growing through the accretion of matter in their outskirts. This process induces inhomogeneities in the gas density distribution (clumping) that need to be taken into account to recover the physical properties of the intracluster medium (ICM) at large radii.
Aims: We studied the thermodynamic properti…