Search Publications
The ACS LCID Project. X. The Star Formation History of IC 1613: Revisiting the Over-cooling Problem
Ferguson, Henry C.; Dolphin, Andrew E.; Skillman, Evan D. +13 more
We present an analysis of the star formation history (SFH) of a field near the half-light radius in the Local Group dwarf irregular galaxy IC 1613 based on deep Hubble Space Telescope Advanced Camera for Surveys imaging. Our observations reach the oldest main sequence turn-off, allowing a time resolution at the oldest ages of ~1 Gyr. Our analysis …
Near-infrared transmission spectrum of the warm-Uranus GJ 3470b with the Wide Field Camera-3 on the Hubble Space Telescope
Ségransan, D.; Bonfils, X.; Ehrenreich, D. +7 more
The atmospheric composition of super-Earths and Neptunes is the object of intense observational and theoretical investigations. Transmission spectra recently obtained for such exoplanets are featureless in the near infrared. This flat signature is attributed to the presence of optically-thick clouds or translucent hazes. The planet
Herschel Finds Evidence for Stellar Wind Particles in a Protostellar Envelope: Is This What Happened to the Young Sun?
Ceccarelli, C.; Dominik, C.; Caux, E. +4 more
There is evidence that the young Sun emitted a high flux of energetic (>=10 MeV) particles. The collisions of these particles with the material at the inner edge of the Protosolar Nebula disk induced spallation reactions that formed short-lived radionuclei, like 10Be, whose trace is now visible in some meteorites. However, it is poor…
A massive galaxy in its core formation phase three billion years after the Big Bang
Kirkpatrick, Allison; Franx, Marijn; van Dokkum, Pieter +13 more
Most massive galaxies are thought to have formed their dense stellar cores in early cosmic epochs. Previous studies have found galaxies with high gas velocity dispersions or small apparent sizes, but so far no objects have been identified with both the stellar structure and the gas dynamics of a forming core. Here we report a candidate core in the…
Early turbulent mixing as the origin of chemical homogeneity in open star clusters
Krumholz, Mark R.; Feng, Yi
The abundances of elements in stars are critical clues to stars' origins. Observed star-to-star variations in logarithmic abundance within an open star cluster--a gravitationally bound ensemble of stars in the Galactic plane--are typically only about 0.01 to 0.05 over many elements, which is noticeably smaller than the variation of about 0.06 to 0…
Searching for oscillations in the primordial power spectrum. II. Constraints from Planck data
Spergel, David N.; Meerburg, P. Daniel; Wandelt, Benjamin D.
In this second of two papers we apply our recently developed code to search for resonance features in the Planck CMB temperature data. We search both for log-spaced oscillations or linear-spaced oscillations and compare our findings with results of our WMAP9 analysis and the Planck team analysis [P. A. R. Ade et al. (Planck Collaboration>), arX…
Evolution of the 12 July 2012 CME from the Sun to the Earth: Data-constrained three-dimensional MHD simulations
Hess, Phillip; Wang, Yuming; Shen, Fang +5 more
The dynamic process of coronal mass ejections (CMEs) in the heliosphere provides us the key information for evaluating CMEs' geoeffectiveness and improving the accurate prediction of CME-induced shock arrival time at the Earth. We present a data-constrained three-dimensional (3-D) magnetohydrodynamic (MHD) simulation of the evolution of the CME in…
The mass-metallicity relation at z ∼ 1.4 revealed with Subaru/FMOS
Curtis-Lake, Emma; Tamura, Naoyuki; Ohta, Kouji +16 more
We present a stellar mass-metallicity relation at z ∼ 1.4 with an unprecedentedly large sample of ∼340 star-forming galaxies obtained with Fibre Multi-Object Spectrograph (FMOS) on the Subaru Telescope. We observed K-band selected galaxies at 1.2 ≤ zph ≤ 1.6 in the Subaru XMM-Newton Deep Survey/Ultra Deep Survey fields with M*
The W43-MM1 mini-starburst ridge, a test for star formation efficiency models
Hill, T.; Csengeri, T.; Bontemps, S. +13 more
Context. Star formation efficiency (SFE) theories are currently based on statistical distributions of turbulent cloud structures and a simple model of star formation from cores. They remain poorly tested, especially at the highest densities.
Aims: We investigate the effects of gas density on the SFE through measurements of the core formation …
The thermal Sunyaev-Zel'dovich effect power spectrum in light of Planck
Holder, G. P.; Le Brun, A. M. C.; McCarthy, I. G. +1 more
The amplitude of the thermal Sunyaev-Zel'dovich effect (tSZ) power spectrum is extremely sensitive to the abundance of the most massive dark matter haloes (galaxy clusters) and therefore to fundamental cosmological parameters that control their growth, such as σ8 and Ωm. Here we explore the sensitivity of the tSZ power spectr…