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The solar neighbourhood contains disc stars that have recently crossed spiral arms in the Galaxy. We propose that boundaries in local velocity distributions separate stars that have recently crossed and been more strongly perturbed by a particular arm from those that haven't. Ridges in the stellar velocity distributions constructed from the second Gaia data release trace orbits that could have tou
The gravitational interaction between two objects on similar orbits can effect noticeable changes in the orbital evolution even if the ratio of their masses to that of the central body is vanishingly small. Christou (Icarus 174:215–229, 2005) observed an occasional resonant lock in the differential node ΔΩ between two members in the Himalia irregular satellite group of Jupiter in the N-body simula
In extending the analysis of the four secular resonances between close orbits in Li and Christou (Celest Mech Dyn Astron 125:133–160, 2016) (Paper I), we generalise the semianalytical model so that it applies to both prograde and retrograde orbits with a one-to-one map between the resonances in the two regimes. We propose the general form of the critical angle to be a linear combination of apsidal
We explore the connections between stellar age, chemistry, and kinematics across a Galactocentric distance of 7.5 < R(kpc) < 9.0, using a sample of ~12 000 intermediate-mass (FGK) turn-offstars observed with the RAdial Velocity Experiment (RAVE) survey. The kinematics of this sample are determined using radial velocity measurements from RAVE, and parallax and proper mo
Among the irregular satellites orbiting Jupiter, the Himalia family is characterized by a high velocity dispersion dv of several hundred m s-1 among its members, inconsistent with a collisional origin. Efforts to account for this through internecine gravitational interactions do not readily reproduce this feature. Here, we revisit the problem in the context of recent cosmogonical models, where the
More than 50 irregular satellites revolve around Jupiter and more than 30 around Saturn. There, at least three collisional families were identified. Among these, the Himalia family of prograde irregular moons at Jupiter is characterised by a velocity dispersion of several hundred m/s, inconsistent with a collisional origin (Nesvorný et al., 2003). Here we investigate whether the dispersion could s
We characterize the selection function of RAdial Velocity Experiment (RAVE) using 2 Micron All Sky Survey (2MASS) as our underlying population, which we assume represents all stars that could have potentially been observed.We evaluate the completeness fraction as a function of position, magnitude and colour in two ways: first, on a field-by-field basis, and second, in equal-size areas on the sky.
Året är 2053 och den svenska regeringen har just invigt museet FOSSIL och dess första utställning ’Carbon Ruins’. År 2045 uppnådde Sverige nettonollutsläpp av växthusgaser, och blev därmed det första landet i världen att lämna den fossila tidsåldern (1849 - 2049). Två hundra år som förde med sig en otrolig välståndsökning, men också oljerelaterade konflikter och en klimatkatastrof som allvarligt hIt is 2053. The Swedish government has just opened its landmark museum FOSSIL with its first exhibition Carbon Ruins. The exhibition and its grand opening is a celebration of the fact that global net-zero emissions of carbon dioxide were reached in 2050. Sweden, in line with its 2017 targets, reached net-zero emissions of greenhouse gases already in 2045, being the first country in the world to st
Context. Aims. The goal of this paper is to demonstrate the outstanding quality of the second data release of the Gaia mission and its power for constraining many different aspects of the dynamics of the satellites of the Milky Way. We focus here on determining the proper motions of 75 Galactic globular clusters, nine dwarf spheroidal galaxies, one ultra-faint system,
Context. The ESA Gaia mission provides a unique time-domain survey for more than 1.6 billion sources with G ≲ 21 mag. Aims. We showcase stellar variability in the Galactic colour-absolute magnitude diagram (CaMD). We focus on pulsating, eruptive, and cataclysmic variables, as well as on stars that exhibit variability that is due to rotation and eclipses. Methods. We describe the locations of var
Context. The second release of Gaia data (Gaia DR2) contains the astrometric parameters for more than half a million quasars. This set defines a kinematically non-rotating reference frame in the optical domain. A subset of these quasars have accurate VLBI positions that allow the axes of the reference frame to be aligned with the International Celestial Reference System (ICRF) radio frame. Aims. W
Mutations are not identified in ~5% of hemophilia A and 10-35% of type 1 VWD patients. The bleeding tendency also varies among patients carrying the same causative mutation, potentially indicating variants in additional genes modifying the phenotype that cannot be identified by routine single-gene analysis. The F8, F9 and VWF genes were analyzed in parallel using an AmpliSeq strategy and Ion Torre
The effect of napping versus wakefulness was studied on primed and repeated Remote Associate Tests (RATs) and on divergent creativity tests. The participants were 42 students from the USA, studying international courses at a Swedish university. The hypotheses for the RATs were (1), when the correct answers were primed before the nap, the RAT should be solved better for those who entered REM sleep,
The future opportunities for high-density QCD studies with ion and proton beams at the LHC are presented. Four major scientific goals are identified: the characterisation of the macroscopic long wavelength Quark-Gluon Plasma (QGP) properties with unprecedented precision, the investigation of the microscopic parton dynamics underlying QGP properties, the development of a unified picture of particle
