Search Publications
The discovery and dynamical evolution of an object at the outer edge of Saturn’s A ring
Murray, Carl D.; Cooper, Nicholas J.; Williams, Gareth A. +2 more
We report on the serendipitous discovery of an unresolved, evolving, sub-km-radius object with a semimajor axis <10 km inside that of the edge of Saturn’s main rings. The object has been detectable in Cassini images since at least May 2012 and its changing orbit shows evidence of a possible disruption in early 2013.
Stability of spinning satellite under axial thrust and internal mass motion
Janssens, Frank L.; van der Ha, Jozef C.
This paper considers a spinning rigid body and a particle with internal motion under axial thrust. This model is helpful for gaining insights into the nutation anomalies that occurred near the end of orbit injections performed by STAR-48 rocket motors. The stability of this system is investigated by means of linearized equations about a uniform sp…
Characterization and Physical Explanation of Energetic Particles on Planck HFI Instrument
Bock, J. J.; Catalano, A.; Coulais, A. +30 more
The Planck High Frequency Instrument (HFI) has been surveying the sky continuously from the second Lagrangian point (L2) between August 2009 and January 2012. It operates with 52 high impedance bolometers cooled at 100 mK in a range of frequency between 100 GHz and 1 THz with unprecedented sensitivity, but strong coupling with cosmic radiation. At…
In-flight calibration of double-probe electric field measurements on Cluster
André, M.; Eriksson, A. I.; Khotyaintsev, Y. V. +2 more
Double-probe electric field instrument with long wire booms is one of the most popular techniques for in situ measurement of electric fields in plasmas on spinning spacecraft platforms, which have been employed on a large number of space missions. Here we present an overview of the calibration procedure used for the Electric Field and Wave (EFW) i…
Probing mass segregation in the globular cluster NGC 6397
Kepler, S. O.; Costa, J. E. S.; Bonatto, C. +3 more
In this study, we present a detailed study of mass segregation in the globular cluster NGC 6397. First, we carry out a photometric analysis of projected European Southern Observatory (ESO)-Very Large Telescope (VLT) data (between 1 and 10 arcmin from the cluster centre), presenting the luminosity function corrected by completeness. The luminosity …
Turbulence in the Earth's cusp region: The k-filtering analysis
Dunlop, Malcolm; Cao, Jin-Bin; Fu, Huishan +2 more
On 13 April 2002, four Cluster spacecraft with separations up to 127 km measured similar turbulence in the exterior cusp during northward interplanetary magnetic field (IMF) Bz. Both the power spectra of magnetic and electric field fluctuations resemble the classical Kolmogorov power law, with the scaling f-1.7 under the prot…
Effects of cosmic strings with delayed scaling on CMB anisotropy
Yokoyama, Jun'ichi; Kamada, Kohei; Miyamoto, Yuhei +1 more
The network of cosmic strings generated in a phase transition during inflation enters the scaling regime later than that of usual strings. If it occurs after the recombination, temperature anisotropies of the cosmic microwave background (CMB) at high multipole moments are significantly reduced. In this paper, we study such effects qualitatively an…
Solar Wind Electron Strahls Associated with a High-Latitude CME: Ulysses Observations
Lazar, M.; Poedts, S.; Pomoell, J. +2 more
Counterstreaming beams of electrons are ubiquitous in coronal mass ejections (CMEs) - although their existence is not unanimously accepted as a necessary and/or sufficient signature of these events. We continue the investigation of a high-latitude CME registered by the Ulysses spacecraft on 18 - 19 January 2002 (Dumitrache, Popescu, and Oncica, So…
Reconciling BICEP2 and Planck results with right-handed Dirac neutrinos in the fundamental representation of grand unified E6
Anchordoqui, Luis A.; Goldberg, Haim; Vlcek, Brian J. +1 more
The tensor-to-scalar ratio (r = 0.20+0.07-0.05) inferred from the excess B-mode power observed by the Background Imaging of Cosmic Extragalactic Polarization (BICEP2) experiment is almost twice as large as the 95% CL upper limits derived from temperature measurements of the WMAP (r < 0.13) and Planck (r < 0.11) space mi…
Validation of the k-filtering technique for a signal composed of random-phase plane waves and non-random coherent structures
Li, X.; Roberts, O. W.; Jeska, L.
Recent observations of astrophysical magnetic fields have shown the presence of fluctuations being wave-like (propagating in the plasma frame) and those described as being structure-like (advected by the plasma bulk velocity). Typically with single-spacecraft missions it is impossible to differentiate between these two fluctuations, due to the inh…