Search Publications
Missions
Journals
Publication Years
Kinematics and dynamics of Gaia red clump stars. Revisiting north-south asymmetries and dark matter density at large heights
Robin, Annie C.; Famaey, Benoit; Bienaymé, Olivier +2 more
In this study, we analyse the kinematics and dynamics of a homogeneous sample of red clump stars, selected from the second Gaia data release catalogue in the direction of the Galactic poles, at five different positions in the plane. The level of completeness of the sample at heights between 0.6 and 3.5 kpc was asserted through a comparison with th…
The Milky Way's Shell Structure Reveals the Time of a Radial Collision
Widrow, Lawrence M.; Sanderson, Robyn; Newberg, Heidi Jo +1 more
We identify shell structures in the Milky Way for the first time. We find two shells in the Virgo Overdensity region and two shells in the Hercules Aquila Cloud region using Sloan Digital Sky Survey, Gaia, and LAMOST data. These shell stars are a subset of the substructure previously identified as the Virgo Radial Merger (VRM). Timing arguments fo…
Tidal Inflation Reconciles Low-density Sub-Saturns with Core Accretion
Batygin, Konstantin; Millholland, Sarah; Petigura, Erik
While the solar system contains no planets between the sizes of Uranus and Saturn, our current exoplanet census includes several dozen such planets with well-measured masses and radii. These sub-Saturns exhibit a diversity of bulk densities, ranging from ∼0.1 to 3 g cm-3. When modeled simply as hydrogen/helium envelopes atop rocky cores…
The MUSE-Faint survey. I. Spectroscopic evidence for a star cluster in Eridanus 2 and constraints on MACHOs as a constituent of dark matter
Bacon, Roland; Boogaard, Leindert A.; Brinchmann, Jarle +9 more
Aims: It has been shown that the ultra-faint dwarf galaxy Eridanus 2 may host a stellar cluster in its centre. If this cluster is shown to exist, it can be used to set constraints on the mass and abundance of massive astrophysical compact halo objects (MACHOs) as a form of dark matter. Previous research has shown promising expectations in the…
Evolution of a Long-Duration Coronal Mass Ejection and Its Sheath Region Between Mercury and Earth on 9-14 July 2013
Farrugia, C. J.; Lugaz, N.; Winslow, R. M.
Using in situ measurements and remote-sensing observations, we study a coronal mass ejection (CME) that left the Sun on 9 July 2013 and impacted both Mercury and Earth while the planets were in radial alignment (within 3∘). The CME had an initial speed as measured by coronagraphs of 580 ± 20 km/s, an inferred speed at Mercury of 580 ± 30 km/s, and…
Detailed 3D structure of Orion A in dust with Gaia DR2
Bailer-Jones, Coryn A. L.; Soler, Juan D.; Rezaei Kh., Sara +1 more
The unprecedented astrometry from Gaia's second data release (DR2) provides us with an opportunity to study molecular clouds in the solar neighbourhood in detail. Extracting the wealth of information in these data remains a challenge, however. We have further improved our Gaussian-processes-based, three-dimensional dust mapping technique to allow …
Predicting accreted satellite galaxy masses and accretion redshifts based on globular cluster orbits in the E-MOSAICS simulations
Trujillo-Gomez, Sebastian; Crain, Robert A.; Kruijssen, J. M. D. +4 more
The ages and metallicities of globular clusters (GCs) are known to be powerful tracers of the properties of their progenitor galaxies, enabling their use in determining the merger histories of galaxies. However, while useful in separating GCs into individual accretion events, the orbits of GC groups themselves have received less attention as probe…
Simultaneous TESS and NGTS transit observations of WASP-166 b
Wheatley, Peter J.; Bayliss, Daniel; Casewell, Sarah L. +21 more
We observed a transit of WASP-166 b using nine Next Generation Transit Survey (NGTS) telescopes simultaneously with the Transiting Exoplanet Survey Satellite (TESS) observations of the same transit. We achieved a photometric precision of 152 ppm per 30 min with the nine NGTS telescopes combined, matching the precision reached by TESS for the trans…
20 Years of ACE Data: How Superposed Epoch Analyses Reveal Generic Features in Interplanetary CME Profiles
Auchère, F.; Démoulin, P.; Dasso, S. +4 more
Interplanetary coronal mass ejections (ICMEs) are magnetic structures propagating from the Sun's corona to the interplanetary medium. With over 20 years of observations at the L1 libration point, ACE offers hundreds of ICMEs detected at different times during several solar cycles and with different features such as the propagation speed. We invest…
Jet feedback and the photon underproduction crisis in SIMBA
Davé, Romeel; Christiansen, Jacob F.; Sorini, Daniele +1 more
We examine the impact of black hole jet feedback on the properties of the low-redshift intergalactic medium (IGM) in the SIMBA simulation, with a focus on the Lyα forest mean flux decrement DA. Without jet feedback, we confirm the photon underproduction crisis (PUC) in which ΓH I at $z$ = 0 must be increased by 6 times over t…