Search Publications
The Most Ancient Spiral Galaxy: A 2.6-Gyr-old Disk with a Tranquil Velocity Field
Kewley, Lisa J.; Richard, Johan; Gupta, Anshu +7 more
We report an integral-field spectroscopic (IFS) observation of a gravitationally lensed spiral galaxy A1689B11 at redshift z = 2.54. It is the most ancient spiral galaxy discovered to date and the second kinematically confirmed spiral at z≳ 2. Thanks to gravitational lensing, this is also by far the deepest IFS observation with the highest spatial…
Plasma Beta Stratification in the Solar Atmosphere: A Possible Explanation for the Penumbra Formation
Bourdin, Ph. -A.
Plasma beta is an important and fundamental physical quantity in order to understand plasma dynamics, particularly in the context of magnetically active stars, because it tells about the domination of magnetic versus thermodynamic processes on the plasma motion. We estimate the value ranges of plasma beta in different regions within the solar atmo…
Transient brightening of Jupiter's aurora observed by the Hisaki satellite and Hubble Space Telescope during approach phase of the Juno spacecraft
Fujimoto, M.; Yoshioka, K.; Gray, R. L. +11 more
In early 2014, continuous monitoring with the Hisaki satellite discovered transient auroral emission at Jupiter during a period when the solar wind was relatively quiet for a few days. Simultaneous imaging made by the Hubble Space Telescope (HST) suggested that the transient aurora is associated with a global magnetospheric disturbance that spans …
The eMERGE Survey - I: Very Large Array 5.5 GHz observations of the GOODS-North Field
Guidetti, D.; Bondi, M.; Prandoni, I. +8 more
We present new observations of the GOODS-N field obtained at 5.5 GHz with the Karl G. Jansky Very Large Array. The central region of the field was imaged to a median rms of 3 µJy beam-1 with a resolution of 0.5 arcsec. From a 14-arcmin diameter region, we extracted a sample of 94 radio sources with signal-to-noise ratio greater th…
Evolution of the physical properties of dust and cometary dust activity from 67P/Churyumov-Gerasimenko measured in situ by Rosetta/COSIMA
Altobelli, Nicolas; Langevin, Yves; Fischer, Henning +9 more
The Cometary Secondary Ion Mass Analyzer (COSIMA) collects dust particles in the coma of 67P/Churyumov-Gerasimenko, images them with a resolution of 14 µm × 14 µm, and measures their composition via time-of-flight secondary ion mass spectrometry. The particles are collected on targets exposed to the cometary flux for periods ranging fr…
Multipoint analysis of compressive fluctuations in the fast and slow solar wind
Escoubet, C. P.; Narita, Y.; Li, X. +2 more
Compressible turbulence in the solar wind is a topic of much recent debate. To understand the various compressive fluctuations at scales comparable to proton characteristic lengths, we use multipoint magnetic field and density data (derived from spacecraft potential which allows higher time resolution than is typically possible than with particle …
Production of O2 through dismutation of H2O2 during water ice desorption: a key to understanding comet O2 abundances
Bockelée-Morvan, D.; Dulieu, F.; Minissale, M.
Context. Detection of molecular oxygen and prediction of its abundance have long been a challenge for astronomers. The low abundances observed in few interstellar sources are well above the predictions of current astrochemical models. During the Rosetta mission, an unexpectedly high abundance of O2 was discovered in the comet 67P/Churyu…
Interstellar-medium Mapping in M82 through Light Echoes around Supernova 2014J
Baade, Dietrich; Sparks, William B.; Wang, Lifan +10 more
We present multiple-epoch measurements of the size and surface brightness of the light echoes from supernova (SN) 2014J in the nearby starburst galaxy M82. Hubble Space Telescope (HST) ACS/WFC images were taken ∼277 and ∼416 days after B-band maximum in the filters F475W, F606W, and F775W. Observations with HST WFC3/UVIS images at epochs ∼216 and …
H0LiCOW. VI. Testing the fidelity of lensed quasar host galaxy reconstruction
Treu, Tommaso; Marshall, Philip J.; Sonnenfeld, Alessandro +11 more
The empirical correlation between the mass of a supermassive black hole (M_BH) and its host galaxy properties is widely considered to be an evidence of their co-evolution. A powerful way to test the co-evolution scenario and learn about the feedback processes linking galaxies and nuclear activity is to measure these correlations as a function of r…
New Evidence for the Dynamical Decay of a Multiple System in the Orion Kleinmann-Low Nebula
Luhman, K. L.; Robberto, M.; Manara, C. F. +5 more
We have measured astrometry for members of the Orion Nebula Cluster with images obtained in 2015 with the Wide Field Camera 3 on board the Hubble Space Telescope. By comparing those data to previous measurements with the Near-Infrared Camera and Multi-Object Spectrometer on Hubble in 1998, we have discovered that a star in the Kleinmann-Low Nebula…