Search Publications
Fermi Non-detections of Four X-Ray Jet Sources and Implications for the IC/CMB Mechanism
Georganopoulos, Markos; Breiding, Peter; Meyer, Eileen T. +3 more
Since its launch in 1999, the Chandra X-ray observatory has discovered several dozen X-ray jets associated with powerful quasars. In many cases, the X-ray spectrum is hard and appears to come from a second spectral component. The most popular explanation for the kpc-scale X-ray emission in these cases has been inverse-Compton (IC) scattering of Co…
Properties of Turbulence in the Reconnection Exhaust: Numerical Simulations Compared with Observations
Sorriso-Valvo, L.; Goldman, M. V.; Newman, D. L. +6 more
The properties of the turbulence that develops in the outflows of magnetic reconnection have been investigated using self-consistent plasma simulations, in three dimensions. As commonly observed in space plasmas, magnetic reconnection is characterized by the presence of turbulence. Here we provide a direct comparison of our simulations with report…
SPHERE/ZIMPOL observations of the symbiotic system R Aquarii. I. Imaging of the stellar binary and the innermost jet clouds
Quanz, S. P.; Siebenmorgen, R.; Stute, M. +40 more
Context. R Aqr is a symbiotic binary system consisting of a mira variable, a hot companion with a spectacular jet outflow, and an extended emission line nebula. Because of its proximity to the Sun, this object has been studied in much detail with many types of high resolution imaging and interferometric techniques. We have used R Aqr as test targe…
Suprathermal electron acceleration in the near-Earth flow rebounce region
Cao, J. B.; Xu, Y.; Yao, Z. H. +4 more
Flux pileup regions (FPRs) are traditionally referred to the strong-Bz bundles behind dipolarization fronts (DFs) in the Earth's magnetotail and can appear both inside earthward and tailward bursty bulk flows. It has been widely reported that suprathermal electrons (40-200 keV) can be efficiently accelerated inside earthward FPRs, leavi…
Observational Evidence for the Associated Formation of Blobs and Raining Inflows in the Solar Corona
Davies, J. A.; Lavraud, B.; Kilpua, E. +6 more
The origin of the slow solar wind is still a topic of much debate. The continual emergence of small transient structures from helmet streamers is thought to constitute one of the main sources of the slow wind. Determining the height at which these transients are released is an important factor in determining the conditions under which the slow sol…
H2CO Distribution and Formation in the TW HYA Disk
Wilner, David J.; Cleeves, L. Ilsedore; Andrews, Sean M. +8 more
H2CO is one of the most readily detected organic molecules in protoplanetary disks. Yet its distribution and dominant formation pathway(s) remain largely unconstrained. To address these issues, we present ALMA observations of two H2CO lines ({3}12{--}{2}11 and {5}15{--}{4}14) at 0.″…
A Statistical Study of CME Properties and of the Correlation Between Flares and CMEs over Solar Cycles 23 and 24
Romano, P.; Zuccarello, F.; Compagnino, A.
We investigated some properties of coronal mass ejections (CMEs), such as speed, acceleration, polar angle, angular width, and mass, using data acquired by the Large Angle Spectrometric Coronagraph (LASCO) onboard the Solar and Heliospheric Observatory (SOHO) from 31 July 1997 to 31 March 2014, i.e. during the Solar Cycles 23 and 24. We used two C…
Large Magellanic Cloud Near-infrared Synoptic Survey. IV. Leavitt Laws for Type II Cepheid Variables
Macri, Lucas M.; Rejkuba, Marina; Ngeow, Chow-Choong +3 more
We present time-series observations of Population II Cepheids in the Large Magellanic Cloud at near-infrared (JHK s ) wavelengths. Our sample consists of 81 variables with accurate periods and optical (VI) magnitudes from the OGLE survey, covering various subtypes of pulsators (BL Herculis, W Virginis, and RV Tauri). We generate light-…
CoMaLit - V. Mass forecasting with proxies: method and application to weak lensing calibrated samples
Sereno, Mauro; Ettori, Stefano
Mass measurements of astronomical objects are most wanted but still elusive. We need them to trace the formation and evolution of cosmic structure but we can get direct measurements only for a minority. This lack can be circumvented with a proxy and a scaling relation. The twofold goal of estimating the unbiased relation and finding the right prox…
Detection of buckminsterfullerene emission in the diffuse interstellar medium
Joblin, C.; Berné, O.; Cox, N. L. J. +1 more
Emission of fullerenes in their infrared vibrational bands has been detected in space near hot stars. The proposed attribution of the diffuse interstellar bands at 9577 and 9632 Å to electronic transitions of the buckminsterfullerene cation (i.e. C60+) was recently supported by new laboratory data, confirming the presence of …