Search Publications
Comparison of active region upflow and core properties using simultaneous spectroscopic observations from IRIS and Hinode
Barczynski, Krzysztof; Brooks, David H.; Kleint, Lucia +2 more
Context. The origin of the slow solar wind is still an open issue. It has been suggested that upflows at the edge of active regions are a possible source of the plasma outflow and therefore contribute to the slow solar wind.
Aims: We investigate the origin and morphology of the upflow regions and compare the upflow region and the active regio…
The eROSITA Final Equatorial-Depth Survey (eFEDS). An X-ray-bright, extremely luminous infrared galaxy at z = 1.87
Nandra, Kirpal; Ueda, Yoshihiro; Terashima, Yuichi +15 more
In this study, we investigate the X-ray properties of WISE J090924.01+000211.1 (WISEJ0909+0002), an extremely luminous infrared (IR) galaxy (ELIRG) at zspec = 1.871 in the eROSITA Final Equatorial-Depth Survey. WISEJ0909+0002 is a WISE 22 µm source, located in the GAMA-09 field, which was detected by eROSITA during the performance…
The first GeV flare of the radio-loud narrow-line Seyfert 1 galaxy PKS 2004-447
Buson, S.; Wilms, J.; Kadler, M. +8 more
Context. On 2019 October 25, the Fermi-Large Area Telescope observed the first ever γ-ray flare from the radio-loud narrow-line Seyfert 1 galaxy PKS 2004−447 (z = 0.24). Prior to this discovery, only four sources of this type had shown a flare at gigaelectronvolt energies.
Aims: We report on follow-up observations in the radio, optical-UV, an…
Cold ion energization at separatrices during magnetic reconnection
Divin, A.; Deca, J.; Markidis, S. +5 more
Separatrices of magnetic reconnection host intense perpendicular Hall electric fields. The fields are produced by the decoupling of the ion and electron components and are associated with the in-plane electrostatic potential drop between the inflow and outflow regions. The width of these structures is typically less than the ion inertial length, w…
Sympathetic Standard and Blowout Coronal Jets Observed in a Polar Coronal Hole
Shen, Yuandeng; Zhou, Chengrui; Zhou, Xinping +4 more
We present the sympathetic eruption of a standard and a blowout coronal jet originating from two adjacent coronal bright points (CBP1 and CBP2) in a polar coronal hole, using soft X-ray and extreme-ultraviolet observations respectively taken by the Hinode and the Solar Dynamics Observatory. In the event, a collimated jet with obvious westward late…
The Structural Connection between Coronal Mass Ejection Flux Ropes near the Sun and at 1 au
Gopalswamy, N.; Xie, H.; Akiyama, S.
We have performed the first comprehensive statistical analysis comparing flux rope (FR) structures of coronal mass ejections (CMEs) near the Sun and at 1 au, using Solar and Heliospheric Observatory and Solar Terrestrial Relations Observatory measurements for the two full solar cycles 23 and 24. This study aims to investigate the physical connecti…
Visibility Interpolation in Solar Hard X-Ray Imaging: Application to RHESSI and STIX
Massa, Paolo; Piana, Michele; Perracchione, Emma +1 more
Space telescopes for solar hard X-ray imaging provide observations made of sampled Fourier components of the incoming photon flux. The aim of this study is to design an image reconstruction method relying on enhanced visibility interpolation in the Fourier domain. The interpolation-based method is applied to synthetic visibilities generated by mea…
Kepler K2 Campaign 9 - I. Candidate short-duration events from the first space-based survey for planetary microlensing
Poleski, R.; Mao, S.; Penny, M. T. +6 more
We present the first short-duration candidate microlensing events from the Kepler K2 mission. From late April to early July 2016, Campaign 9 of K2 obtained high temporal cadence observations over a 3.7 deg2 region of the Galactic bulge. Its primary objectives were to look for evidence of a free-floating planet (FFP) population using mic…
Evaluation of a potential field source surface model with elliptical source surfaces via ballistic back mapping of in situ spacecraft data
Wimmer-Schweingruber, R. F.; Kruse, M.; Heidrich-Meisner, V.
Context. The potential field source surface (PFSS) model is an important tool that helps link the solar coronal magnetic field to the solar wind. Due to its simplicity, it allows for predictions to be computed rapidly and requires little input data, though at the cost of reduced accuracy compared to more complex models. So far, PFSS models have al…
Large eddy simulations of the Martian convective boundary layer: Towards developing a new planetary boundary layer scheme
Mischna, Michael A.; Karatekin, Özgür; Senel, Cem Berk +5 more
The grid resolutions typically employed in atmospheric global circulation and mesoscale models are not sufficient to explicitly resolve the turbulence processes within the planetary boundary layer (PBL). turbulent fluxes are, therefore, fully parameterized in those models, based on empirical relationships for the mixing length scale using PBL sche…