Search Publications
The Complex Structure of Magnetic Field Discontinuities in the Turbulent Solar Wind
Perri, S.; Veltri, P.; Yordanova, E. +2 more
Using high-resolution Cluster satellite observations and a multi-dimensional intermittency technique, we show that the magnetic discontinuities in the turbulent solar wind are connected through the spatial scales, going from proton down to electron scales. In some circumstances, their structure resembles the Harris equilibrium profile in plasmas. …
Solar Cycle 25: Another Moderate Cycle?
Schüssler, M.; Jiang, J.; Cameron, R. H.
Surface flux transport simulations for the descending phase of Cycle 24 using random sources (emerging bipolar magnetic regions) with empirically determined scatter of their properties provide a prediction of the axial dipole moment during the upcoming activity minimum together with a realistic uncertainty range. The expectation value for the dipo…
Cold Milky Way HI Gas in Filaments
Kerp, J.; Winkel, B.; Lenz, D. +4 more
We investigate data from the Galactic Effelsberg-Bonn H I Survey, supplemented with data from the third release of the Galactic All Sky Survey (GASS III) observed at Parkes. We explore the all-sky distribution of the local Galactic H I gas with | {v}{{LSR}}| \lt 25 km s-1 on angular scales of 11‧-16‧. Unsharp masking is appli…
Hooked Flare Ribbons and Flux-rope-related QSL Footprints
Li, Hui; Aulanier, Guillaume; Schmieder, Brigitte +3 more
We studied the magnetic topology of active region 12158 on 2014 September 10 and compared it with the observations before and early in the flare that begins at 17:21 UT (SOL2014-09-10T17:45:00). Our results show that the sigmoidal structure and flare ribbons of this active region observed by the Solar Dynamics Observatory/Atmospheric Imaging Assem…
First Images of Debris Disks around TWA 7, TWA 25, HD 35650, and HD 377
Stark, Christopher C.; Schneider, Glenn; Chen, Christine H. +15 more
We present the first images of four debris disks observed in scattered light around the young (4-250 Myr old) M dwarfs TWA 7 and TWA 25, the K6 star HD 35650, and the G2 star HD 377. We obtained these images by reprocessing archival Hubble Space Telescope NICMOS coronagraph data with modern post-processing techniques as part of the Archival Legacy…
The Rotation of the Hot Gas around the Milky Way
Bregman, Joel N.; Miller, Matthew J.; Hodges-Kluck, Edmund J.
The hot gaseous halos of galaxies likely contain a large amount of mass and are an integral part of galaxy formation and evolution. The Milky Way has a 2× {10}6 K halo that is detected in emission and by absorption in the O vii resonance line against bright background active galactic nuclei (AGNs), and for which the best current model i…
Candidate Gravitationally Lensed Dusty Star-forming Galaxies in the Herschel Wide Area Surveys
Ivison, R. J.; Frayer, D. T.; Omont, A. +21 more
We present a list of candidate gravitationally lensed dusty star-forming galaxies (DSFGs) from the HerMES Large Mode Survey and the Herschel Stripe 82 Survey. Together, these partially overlapping surveys cover 372 deg2 on the sky. After removing local spiral galaxies and known radio-loud blazars, our candidate list of lensed DSFGs is c…
Simultaneous IRIS and Hinode/EIS Observations and Modelling of the 2014 October 27 X2.0 Class Flare
Mason, H. E.; Golub, L.; Del Zanna, G. +5 more
We present a study of the X2-class flare which occurred on 2014 October 27 and was observed with the Interface Region Imaging Spectrograph (IRIS) and the EUV Imaging Spectrometer (EIS) on board the Hinode satellite. Thanks to the high cadence and spatial resolution of the IRIS and EIS instruments, we are able to compare simultaneous observations o…
The Interaction of the Fermi Bubbles with the Milky Way’s Hot Gas Halo
Bregman, Joel N.; Miller, Matthew J.
The Fermi bubbles are two lobes filled with non-thermal particles that emit gamma rays, extend ≈ 10 {{kpc}} vertically from the Galactic center, and formed from either nuclear star formation or accretion activity on Sgr A*. Simulations predict a range of shock strengths as the bubbles expand into the surrounding hot gas halo ({T}{halo}≈…
The NuSTAR Extragalactic Surveys: The Number Counts of Active Galactic Nuclei and the Resolved Fraction of the Cosmic X-Ray Background
Harrison, F. A.; Hornstrup, A.; Stern, D. +41 more
We present the 3-8 keV and 8-24 keV number counts of active galactic nuclei (AGNs) identified in the Nuclear Spectroscopic Telescope Array (NuSTAR) extragalactic surveys. NuSTAR has now resolved 33%-39% of the X-ray background in the 8-24 keV band, directly identifying AGNs with obscuring columns up to ∼ {10}25 {{cm}}-2. In t…