Search Publications
Explaining the chemical trajectories of accreted and in-situ halo stars of the Milky Way
Gibson, Brad K.; Kawata, Daisuke; Gallart, Carme +2 more
The Milky Way underwent its last significant merger ten billion years ago, when the Gaia-Enceladus-Sausage (GES) was accreted. Accreted GES stars and progenitor stars born prior to the merger make up the bulk of the inner halo. Even though these two main populations of halo stars have similar durations of star formation prior to their merger, they…
The H α star formation main sequence in cluster and field galaxies at z ∼ 1.6
Cooper, M. C.; Muzzin, Adam; Forrest, Ben +16 more
We calculate H α-based star formation rates and determine the star formation rate-stellar mass relation for members of three Spitzer Adaptation of the Red-Sequence Cluster Survey (SpARCS) clusters at z ~ 1.6 and serendipitously identified field galaxies at similar redshifts to the clusters. We find similar star formation rates in cluster and field…
Collinder 135 and UBC 7: A physical pair of open clusters
Reffert, Sabine; Berczik, Peter; Just, Andreas +7 more
Context. Given the closeness of the two open clusters
Aims: We aim to recover the present-day stellar membership in the open clusters
A surprise in the updated list of stellar perturbers of long-period comet motion
Dybczyński, Piotr A.; Wysoczańska, Rita; Polińska, Magdalena
Context. The second Gaia data release (Gaia DR2) provided us with the precise five-parameter astrometry for 1.3 billion of sources. As stars passing close to the Solar System are thought to influence the dynamical history of long-period comets, we update and extend the list of stars that could potentially perturb the motion of these comets.
A…
The Gaia Ultra-Cool Dwarf Sample - III: seven new multiple systems containing at least one Gaia DR2 ultracool dwarf.
Caballero, J. A.; Sarro, L. M.; Marocco, F. +8 more
We present 10 new ultracool dwarfs in seven wide binary systems discovered using Gaia second data release data, identified as part of our Gaia Ultra-Cool Dwarf Sample project. The seven systems presented here include an L1 companion to the G5 IV star HD 164507, an L1: companion to the V478 Lyr AB system, an L2 companion to the metal-poor K5 V star…
The HSC-SSP Transient Survey: Implications from Early Photometry and Rise Time of Normal Type Ia Supernovae
Tominaga, Nozomu; Nomoto, Ken'ichi; Morokuma, Tomoki +9 more
With a booming number of Type Ia supernovae (SNe Ia) discovered within a few days of their explosions, a fraction of SNe Ia that show luminosity excess in the early phase (early-excess SNe Ia) have been confirmed. In this article, we report early-phase observations of seven photometrically normal SNe Ia (six early detections and one deep non detec…
Four microlensing planets with faint-source stars identified in the 2016 and 2017 season data
Han, Cheongho; Udalski, Andrzej; Lee, Chung-Uk +34 more
Aims: Microlensing planets occurring on faint-source stars can escape detection due to their weak signals. Occasionally, detections of such planets are not reported due to the difficulty of extracting high-profile scientific issues on the detected planets.
Methods: For the solid demographic census of microlensing planetary systems based …
Fine Structures in the Main Sequence Revealed by Gaia Data Release 2
Jao, Wei-Chun; Feiden, Gregory A.
The Hertzsprung-Russell diagram (HRD) is fully examined using the Fourier analysis. This work shows more stars are above the gap in the lower main sequence than below it, and this implies that stars spend more time above the gap while they undergo variability associated with the 3He instability. The enhanced HRD also shows the width of …
The mergers in Abell 2256: displaced gas and its connection to the radio-emitting plasma
Simionescu, A.; Mernier, F.; Werner, N. +5 more
We present the results of deep Chandra and XMM-Newton X-ray imaging and spatially resolved spectroscopy of Abell 2256, a nearby (z = 0.058) galaxy cluster experiencing multiple mergers and displaying a rich radio morphology dominated by a large relic. The X-ray data reveal three subclusters: (I) the 'main cluster'; (II) the remnant of an older mer…
The BepiColombo-Mio Magnetometer en Route to Mercury
Russell, C. T.; Balogh, A.; Zhang, T. L. +26 more
The fluxgate magnetometer MGF on board the Mio spacecraft of the BepiColombo mission is introduced with its science targets, instrument design, calibration report, and scientific expectations. The MGF instrument consists of two tri-axial fluxgate magnetometers. Both sensors are mounted on a 4.8-m long mast to measure the magnetic field around Merc…