相关论文: Explaining Neptune's Eccentricity
Studies of transiting Neptune-size planets orbiting close to nearby bright stars can inform theories of planet formation because mass and radius and therefore mean density can be accurately estimated and compared with interior models. The…
Possible explanations of the recently reported anomalous increase of the eccentricity of the lunar orbit are sought in terms of classical Newtonian mechanics, general relativity, and long-range modifications of gravity.
We report the detection of the secondary eclipse of HAT-P-11 b, a Neptune-sized planet orbiting an active K4 dwarf. Using all available short-cadence data of the Kepler mission, we derive refined planetary ephemeris increasing their…
The Km3NET collaboration has recently reported the detection of a neutrino event with energy in excess of 100 PeV. This detection is in 2.5-3$\sigma$ tension with the upper limit on the neutrino flux at this energy imposed by IceCube and…
The irregular moons orbit the giant planets on distant, inclined, and eccentric trajectories, in sharp contrast with the coplanar and quasicircular orbits of the regular moons. The origin of these irregular moons is still an open question,…
The increasing number of transiting planets raises the possibility of finding changes in their transit time, duration and depth that could be indicative of further planets in the system. Experience from eclipsing binaries indeed shows that…
Recent observations of variability in the ``atmospheric neutrino'' rate place constraints on possible explanations of the atmospheric neutrino anomaly. Many proposed solutions to the problem are static and can not be adapted to the temporal…
Recently, Sheppard et al. (2016) presented the discovery of seven new trans-Neptunian objects with moderate eccentricities, perihelia beyond 40 AU, and semimajor axes beyond 50 AU. Like the few previously known objects on similar orbits,…
The neutrino deficits observed in four solar neutrino experiments, relative to the theoretical predictions, have led to fresh insights into neutrino and solar physics. Neutrino emission from distant, energetic astronomical systems may form…
We suggest that the atmospheric neutrino anomaly observed in the Super-Kamiokande (and other) experiments results from the combined effects of muon-neutrino to tau-neutrino oscillations with a Delta m^2 value of approximately 0.4 eV^2 and…
The number of exoplanets found with periods as short as one day and less was surprising given how fast these planets had been expected to migrate into the star due to the tides raised on the star by planets at such close distances. It has…
Motivated by the indications of a possible deficit of muon tracks in the first three-year equivalent dataset of IceCube we investigate the possibility that the astrophysical (anti)neutrino flux (in the PeV energy range) could originate from…
The eccentricity distribution of exoplanets is known from radial velocity surveys to be divergent from circular orbits beyond 0.1 AU. This is particularly the case for large planets where the radial velocity technique is most sensitive. The…
Planet-planetesimal interactions cause a planet to migrate, manifesting as a random walk in semi-major axis. In models for Neptune's migration involving a gravitational upheaval, this planetesimal-driven migration is a side-effect of the…
Some evidence for sterile neutrinos has been found in short baseline observations where the measured neutrino flux did not agree with expectations. Systematic uncertainties from the expected values has limited the sensitivity of this…
As many as $10^9$ neutron stars populate the Galaxy, but only $\approx 10^3$ are directly observed as pulsars or as accreting sources in X-ray binaries. In principle also the accretion of the interstellar medium may make isolated neutron…
The orbit of Mercury has large values of eccentricity and inclination that cannot be easily explained if this planet formed on a circular and coplanar orbit. Here, we study the evolution of Mercury's orbit during the instability related to…
Aims. We report the discovery of a peculiar object observed serendipitously with XMM-Newton. We present its timing and spectral properties and investigate its optical counterpart. Methods. The light curve of the X-ray source, its spectrum,…
Nbody simulations are used to examine the consequences of Neptune's outward migration into the Kuiper Belt, with the simulated endstates being compared rigorously and quantitatively to the observations. These simulations confirm the…
In this talk, I have discussed some issues of recent interest and activity in the field of neutrino astrophysics and cosmology. The topics are: (1)~The origin of high peculiar velocities of pulsars; (2)~Energization of the supernova shock…