Search Publications
Can tides explain the low dark matter density in Fornax?
Fattahi, Azadeh; Read, Justin I.; Frenk, Carlos S. +1 more
The low dark matter density in the Fornax dwarf galaxy is often interpreted as being due to the presence of a constant density 'core', but it could also be explained by the effects of Galactic tides. The latter interpretation has been disfavoured because it is apparently inconsistent with the orbital parameters and star formation history of Fornax…
Near-infrared transmission spectrum of TRAPPIST-1 h using Hubble WFC3 G141 observations
Marcq, E.; Charnay, B.; Mori, M. +4 more
Context. The TRAPPIST-1 planetary system is favourable for transmission spectroscopy and offers the unique opportunity to study rocky planets with possibly non-primary envelopes. We present here the transmission spectrum of the seventh planet of the TRAPPIST-1 system, TRAPPIST-1 h (RP = 0.752 R⊕, Teq = 173 K) using…
Magnetograph Saturation and the Open Flux Problem
Ulrich, R. K.; Wang, Y. -M.; Harvey, J. W.
Extrapolations of line-of-sight photospheric field measurements predict radial interplanetary magnetic field (IMF) strengths that are factors of ~2-4 too low. To address this open flux problem, we reanalyze the magnetograph measurements from different observatories, with particular focus on those made in the saturation-prone Fe I 525.0 nm line by …
Systematic KMTNet Planetary Anomaly Search. VI. Complete Sample of 2018 Sub-prime-field Planets
Han, Cheongho; Udalski, Andrzej; Lee, Chung-Uk +31 more
We complete the analysis of all 2018 sub-prime-field microlensing planets identified by the KMTNet AnomalyFinder. Among the 9 previously unpublished events with clear planetary solutions, 6 are clearly planetary (OGLE-2018-BLG-0298, KMT-2018-BLG-0087, KMT-2018-BLG-0247, KMT-2018-BLG-0030, OGLE-2018-BLG-1119, and KMT-2018-BLG-2602), while the remai…
A Carbon/Oxygen-dominated Atmosphere Days after Explosion for the "Super-Chandrasekhar" Type Ia SN 2020esm
Kilpatrick, Charles D.; Izzo, Luca; Coulter, David A. +18 more
Seeing pristine material from the donor star in a type Ia supernova (SN Ia) explosion can reveal the nature of the binary system. In this paper, we present photometric and spectroscopic observations of SN 2020esm, one of the best-studied SNe of the class of "super-Chandrasekhar" SNe Ia (SC SNe Ia), with data obtained -12 to +360 days relative to p…
The 3D Kinematics of the Orion Nebula Cluster: NIRSPEC-AO Radial Velocities of the Core Population
Lu, Jessica R.; Kim, Dongwon; Hsu, Chih-Chun +5 more
The kinematics and dynamics of stellar and substellar populations within young, still-forming clusters provide valuable information for constraining theories of formation mechanisms. Using Keck II NIRSPEC+AO data, we have measured radial velocities for 56 low-mass sources within 4' of the core of the Orion Nebula Cluster (ONC). We also remeasure r…
The Stellar Mass Function in CANDELS and Frontier Fields: The Buildup of Low-mass Passive Galaxies since z 3
Santini, Paola; Calabrò, Antonello; Castellano, Marco +8 more
Despite significant efforts in recent years, the physical processes responsible for the formation of passive galaxies through cosmic time remain unclear. The shape and evolution of the stellar mass function (SMF) give an insight into these mechanisms. Taking advantage of the CANDELS and the deep Hubble Frontier Fields (HFF) programs, we estimated …
Evolution of the Sun's activity and the poleward transport of remnant magnetic flux in Cycles 21-24
Banerjee, Dipankar; Karak, Bidya Binay; Kumar, Pawan +4 more
Detailed study of the solar magnetic field is crucial to understand its generation, transport, and reversals. The timing of the reversals may have implications on space weather and thus identification of the temporal behaviour of the critical surges that lead to the polar field reversals is important. We analyse the evolution of solar activity and…
New Craters on Mars: An Updated Catalog
Piqueux, S.; Dundas, C. M.; Werynski, A. +15 more
We present a catalog of new impacts on Mars. These craters formed in the last few decades, constrained with repeat orbital imaging. Crater diameters range from 58 m down to <1 m. For each impact, we report whether it formed a single crater or a cluster (58% clusters); albedo features of the blast zone (88% halos; 64% linear rays; 10% arcuate ra…
The COMBS Survey - III. The chemodynamical origins of metal-poor bulge stars
Kobayashi, Chiaki; Hawkins, Keith; Lucey, Madeline +6 more
The characteristics of the stellar populations in the Galactic bulge inform and constrain the Milky Way's formation and evolution. The metal-poor population is particularly important in light of cosmological simulations, which predict that some of the oldest stars in the Galaxy now reside in its centre. The metal-poor bulge appears to consist of m…