Search Publications
Interface Region Imaging Spectrograph (IRIS) Observations of the Fractal Dimension in the Solar Atmosphere
Aschwanden, Markus J.; Vilangot Nhalil, Nived
While previous work explored the fractality and self-organized criticality (SOC) of flares and nanoflares in wavelengths emitted in the solar corona (such as in hard X-rays, soft X-rays, and EUV wavelenghts), we focus here on impulsive phenomena in the photosphere and transition region, as observed with the {\sl Interface Region Imaging Spectrogra…
Space Physics: The Need for a Wider Perspective
André, Mats
We argue that many studies in space physics would benefit from putting a detailed investigation into a wider perspective. Three examples of theoretical and observational studies are given. We argue that space physics should aim to be less of an isolated branch of science. Rather, by putting the scientific space results into a wider perspective the…
Quaternionic Transform: A new Light on the Solar Power Spectrum
Garrido, Rafael; Ayala, Adrián; Pascual-Granado, Javier +2 more
Asteroseismology, that is, the use of the frequency content of a time series caused by variations in brightness or radial velocity of a stellar object, is based on the hypothesis that such a series is harmonic and therefore can be described by a sum of sines and cosines. If this were not the case (e.g., the oscillations of an ellipsoid of revoluti…
Light Elements in the Universe
Magrini, Laura; Randich, Sofia
Due to their production sites, as well as to how they are processed and destroyed in stars, the light elements are excellent tools to investigate a number of crucial issues in modern astrophysics: from stellar structure and non-standard processes at work in stellar interiors to age dating of stars; from pre-main sequence evolution to the star form…
The Census of Exoplanets in Visual Binaries: population trends from a volume-limited Gaia DR2 and literature search
Fontanive, Clémence; Bardalez Gagliuffi, Daniella
We present results from an extensive search in the literature and Gaia DR2 for visual, co-moving binary companions to stars hosting exoplanets and brown dwarfs within 200 pc. We found 218 planet hosts out of the 938 in our sample to be part of multiple-star systems, with 10 newly discovered binaries and 2 new tertiary stellar components. This repr…
Highlights of Discoveries for δ Scuti Variable Stars From the Kepler Era
Guzik, Joyce Ann
The NASAKeplerand follow-on K2 mission (2009–2018) left a legacy of data and discoveries, finding thousands of exoplanets, and also obtaining high-precision long time-series data for hundreds of thousands of stars, including many types of pulsating variables. Here we highlight a few of the ongoing discoveries fromKeplerdata on δ Scuti pulsating va…
Drag-Based Model (DBM) Tools for Forecast of Coronal Mass Ejection Arrival Time and Speed
Dumbović, Mateja; Temmer, Manuela; Veronig, Astrid +4 more
Forecasting the arrival time of coronal mass ejections (CMEs) and their associated shocks is one of the key aspects of space weather research. One of the commonly used models is the analytical drag-based model (DBM) for heliospheric propagation of CMEs due to its simplicity and calculation speed. The DBM relies on the observational fact that slow …
The spiral structure in the Solar neighbourhood
Hou, L. G.
The spiral structure in the solar neighborhood is an important issue in astronomy. In the past few years, there has been significant progress in observation. The distances for a large number of good spiral tracers, i.e., giant molecular clouds, high-mass star-formation region masers, HII regions, O-type stars, and young open clusters, have been ac…
Plasma and Magnetic Field Turbulence in the Earth's Magnetosheath at Ion Scales
Rakhmanova, Liudmila; Riazantseva, Maria; Zastenker, Georgy
Crossing the Earth's bow shock is known to crucially affect solar wind plasma including changes in turbulent cascade. The present review summarizes results of more than 15 years of experimental exploration into magnetosheath turbulence. Great contributions to understanding turbulence development inside the magnetosheath was made by means of recent…
Investigating Remote-sensing Techniques to Reveal Stealth Coronal Mass Ejections
Nitta, Nariaki V.; Richardson, Ian G.; Srivastava, Nandita +7 more
Eruptions of coronal mass ejections (CMEs) from the Sun are usually associated with a number of signatures that can be identified in solar disc imagery. However, there are cases in which a CME that is well observed in coronagraph data is missing a clear low-coronal counterpart. These events have received attention during recent years, mainly as a …