Search Publications
The optical morphologies of the 2 Jy sample of radio galaxies: evidence for galaxy interactions
Morganti, R.; Tadhunter, C. N.; Ramos Almeida, C. +3 more
We present deep Gemini Multi-Object Spectrograph South (GMOS-S)/Gemini optical broad-band images for a complete sample of 46 southern 2 Jy radio galaxies at intermediate redshifts (0.05 < z < 0.7). Based on them, we discuss the role of galaxy interactions in the triggering of powerful radio galaxies (PRGs). The high-quality observations pres…
Accretion of Saturn’s mid-sized moons during the viscous spreading of young massive rings: Solving the paradox of silicate-poor rings versus silicate-rich moons
Dones, Luke; Charnoz, Sébastien; Crida, Aurélien +7 more
The origin of Saturn’s inner mid-sized moons (Mimas, Enceladus, Tethys, Dione and Rhea) and Saturn’s rings is debated. Charnoz et al. [Charnoz, S., Salmon J., Crida A., 2010. Nature 465, 752-754] introduced the idea that the smallest inner moons could form from the spreading of the rings’ edge while Salmon et al. [Salmon, J., Charnoz, S., Crida, A…
Galactic Cosmic Ray Intensity Response to Interplanetary Coronal Mass Ejections/Magnetic Clouds in 1995 - 2009
Cane, H. V.; Richardson, I. G.
We summarize the response of the galactic cosmic ray (CGR) intensity to the passage of the more than 300 interplanetary coronal mass ejections (ICMEs) and their associated shocks that passed the Earth during 1995 - 2009, a period that encompasses the whole of Solar Cycle 23. In ∼ 80% of cases, the GCR intensity decreased during the passage of thes…
Heating the Hot Atmospheres of Galaxy Groups and Clusters with Cavities: The Relationship between Jet Power and Low-frequency Radio Emission
Giacintucci, S.; O'Sullivan, E.; Ponman, T. J. +4 more
We present scaling relations between jet power and radio power measured using the Giant Metrewave Radio Telescope (GMRT), Chandra, and XMM-Newton, for a sample of nine galaxy groups combined with the Bîrzan et al. sample of clusters. Cavity power is used as a proxy for mechanical jet power. Radio power is measured at 235 MHz and 1.4 GHz, and the i…
First Evidence of Coexisting EIT Wave and Coronal Moreton Wave from SDO/AIA Observations
Chen, P. F.; Wu, Y.
"EIT waves" are a globally propagating wavelike phenomenon. They were often interpreted as fast-mode magnetoacoustic waves in the corona, despite various discrepancies between the fast-mode wave model and observations. To reconcile these discrepancies, we suggested that "EIT waves" are the apparent propagation of the plasma compression due to succ…
SN 2009jf: a slow-evolving stripped-envelope core-collapse supernova
Fugazza, D.; Sollerman, J.; Reichart, D. E. +28 more
We present an extensive set of photometric and spectroscopic data for SN 2009jf, a nearby Type Ib supernova (SN), spanning from ∼20 d before B-band maximum to 1 yr after maximum. We show that SN 2009jf is a slowly evolving and energetic stripped-envelope SN and is likely from a massive progenitor (25-30 M⊙). The large progenitor's mass …
The First Observation of a Rapidly Rotating Coronal Mass Ejection in the Middle Corona
Nieves-Chinchilla, T.; Stenborg, G.; Vourlidas, A. +1 more
In this Letter, we present the first direct detection of a rotating coronal mass ejection (CME) in the middle corona (5-15 R sun). The CME rotation rate is 60° day-1, which is the highest rate reported yet. The Earth-directed event was observed by the STEREO/SECCHI and SOHO/LASCO instruments. We are able to derive the three-d…
SDO AIA and Hinode EIS observations of "warm" loops
Mason, H. E.; Del Zanna, G.; O'Dwyer, B.
We present simultaneous observations of active region "warm" (1 MK) loops using the Solar Dynamics Observatory (SDO) Atmospheric Imaging Assembly (AIA) and Hinode EUV Imaging Spectrometer (EIS). Sample EIS spectra for a loop footpoint and a lop leg region are presented, and are used to describe the spectral lines which contribute to the six AIA EU…
Determination of the X-ray reflection emissivity profile of 1H 0707-495
Fabian, A. C.; Wilkins, D. R.
When considering the X-ray spectrum resulting from the reflection off the surface of accretion discs of AGN, it is necessary to account for the variation in reflected flux over the disc, i.e. the emissivity profile. This will depend on factors including the location and geometry of the X-ray source and the disc characteristics. We directly obtain …
Strong influence of lunar crustal fields on the solar wind flow
Barabash, Stas; Holmström, Mats; Futaana, Yoshifumi +5 more
We discuss the influence of lunar magnetic anomalies on the solar wind and on the lunar surface, based on maps of solar wind proton fluxes deflected by the magnetic anomalies. The maps are produced using data from the Solar WInd Monitor (SWIM) onboard the Chandrayaan-1 spacecraft. We find a high deflection efficiency (average ∼10%, locally ∼50%) o…