Search Publications
Space, time and velocity association of successive coronal mass ejections
Gopalswamy, Nat; Yashiro, Seiji; Lara, Alejandro +2 more
Aims: Our aim is to investigate the possible physical association between consecutive coronal mass ejections (CMEs).
Methods: Through a statistical study of the main characteristics of 27 761 CMEs observed by SOHO/LASCO during the past 20 years.
Results: We found the waiting time (WT) or time elapsed between two consecutive CMEs is …
Water vapour masers in long-period variable stars. II. The semi-regular variables R Crt and RT Vir
Engels, D.; Winnberg, A.; Brand, J.
Context. Water masers emitting at a radiofrequency of 22 GHz are often found in the circumstellar envelopes of evolved stars. We monitored the H2O maser emission of a larger sample of evolved stars of different types to study the maser properties as a function of stellar type.
Aims: We wish to understand the origin and evolution of…
Formation of a tiny flux rope in the center of an active region driven by magnetic flux emergence, convergence, and cancellation
Cao, Wenda; Chen, Yao; Zheng, Ruisheng +2 more
Aims: Flux ropes are generally believed to be core structures of solar eruptions that are significant for the space weather, but their formation mechanism remains intensely debated. We report on the formation of a tiny flux rope beneath clusters of active region loops on 2018 August 24.
Methods: Combining the high-quality multiwavelength…
VLA ammonia observations of L1287. Analysis of the Guitar core and two filaments
Palau, Aina; Rodríguez, Luis F.; Busquet, Gemma +6 more
Aims: In this paper, we study the dense gas of the molecular cloud LDN 1287 (L1287), which harbors a double FU Ori system, an energetic molecular outflow, and a still-forming cluster of deeply embedded low-mass young stellar objects that show a high level of fragmentation.
Methods: We present optical Hα and [SII], and VLA NH3 …
Radial velocity constraints on the long-period transiting planet Kepler-1625 b with CARMENES
Heller, René; Reiners, Ansgar; Zechmeister, Mathias +1 more
Context. The star Kepler-1625 recently attracted considerable attention when an analysis of the stellar photometric time series from the Kepler mission was interpreted as showing evidence of a large exomoon around the transiting Jupiter-sized planet candidate Kepler-1625 b. However, the mass of Kepler-1625 b has not been determined independently a…
NGC 4104: A shell galaxy in a forming fossil group
Adami, C.; Martinet, N.; Cuillandre, J. -C. +4 more
Context. Groups are the most common association of galaxies in the Universe and they are found in different configuration states, such as loose, compact, and fossil groups.
Aims: We studied the galaxy group MKW 4s, dominated by the giant early-type galaxy NGC 4104 at z = 0.0282, with the aim of understanding the evolutionary stage of this gro…
Non-interacting coronal mass ejections and solar energetic particles near the quadrature configuration of Solar TErrestrial RElations Observatory
Ravishankar, Anitha; Michałek, Grzegorz
We present our results on the correlation of non-interacting coronal mass ejections (CMEs) and solar energetic particles (SEPs). A statistical analysis was conducted on 25 SEP events and the associated CME and flare during the ascending phase of solar cycle 24, i.e., 2009-2013, which marks the quadrature configuration of Solar TErrestrial RElation…
Eruptions from coronal hole bright points: Observations and non-potential modelling
Madjarska, Maria S.; Mackay, Duncan H.; Galsgaard, Klaus +2 more
Context. We report on the third part of a series of studies on eruptions associated with small-scale loop complexes named coronal bright points (CBPs).
Aims: A single case study of a CBP in an equatorial coronal hole with an exceptionally large size is investigated to expand on our understanding of the formation of mini-filaments, their desta…
Wide field-of-view study of the Eagle Nebula with the Fourier transform imaging spectrograph SITELLE at CFHT
Prunet, S.; McLeod, A. F.; Flagey, N. +1 more
Context. We present the very first wide-field, 11' by 11', optical spectral mapping of M 16, one of the most famous star-forming regions in the Galaxy. The data were acquired with the new imaging Fourier transform spectrograph SITELLE mounted on the Canada-France-Hawaii Telescope (CFHT). We obtained three spectral cubes with a resolving power of 1…
Discrete element modeling of boulder and cliff morphologies on comet 67P/Churyumov-Gerasimenko
Otto, K. A.; Sachse, M.; Kappel, D. +1 more
Context. Even after the Rosetta mission, some of the mechanical parameters of comet 67P/Churyumov-Gerasimenko's surface material are not yet well constrained. These parameters are needed to improve our understanding of cometary activity or for planning sample return missions.
Aims: We study some of the physical processes involved in the forma…