Search Publications
Missions
Journals
Publication Years
Observational Evidence for High Neutronization in Supernova Remnants: Implications for Type Ia Supernova Progenitors
Mori, Hideyuki; Yamaguchi, Hiroya; Badenes, Carles +8 more
The physical process whereby a carbon-oxygen white dwarf explodes as a Type Ia supernova (SN Ia) remains highly uncertain. The degree of neutronization in SN Ia ejecta holds clues to this process because it depends on the mass and the metallicity of the stellar progenitor, and on the thermodynamic history prior to the explosion. We report on a new…
Magnetic reconnection during eruptive magnetic flux ropes
Lin, J.; Roussev, I. I.; Keppens, R. +1 more
Aims: We perform a three-dimensional (3D) high resolution numerical simulation in isothermal magnetohydrodynamics to study the magnetic reconnection process in a current sheet (CS) formed during an eruption of a twisted magnetic flux rope (MFR). Because the twist distribution violates the Kruskal-Shafranov condition, the kink instability occu…
Gas Sloshing Regulates and Records the Evolution of the Fornax Cluster
Jones, Christine; Nulsen, Paul E. J.; Kraft, Ralph P. +7 more
We present results of a joint Chandra and XMM-Newton analysis of the Fornax Cluster, the nearest galaxy cluster in the southern sky. Signatures of merger-induced gas sloshing can be seen in the X-ray image. We identify four sloshing cold fronts in the intracluster medium, residing at radii of 3 kpc (west), 10 kpc (northeast), 30 kpc (southwest), a…
Dust Abundance Variations in the Magellanic Clouds: Probing the Life-cycle of Metals with All-sky Surveys
Bot, Caroline; Roman-Duval, Julia; Gordon, Karl +1 more
Observations and modeling suggest that dust abundance (gas-to-dust ratio, G/D) depends on (surface) density. Variations of the G/D provide timescale constraints for the different processes involved in the life cycle of metals in galaxies. Recent G/D measurements based on Herschel data suggest a factor of 5-10 decrease in dust abundance between the…
The HDUV Survey: Six Lyman Continuum Emitter Candidates at z ∼ 2 Revealed by HST UV Imaging
Oesch, P. A.; Carollo, C. M.; Nelson, E. J. +14 more
We present six galaxies at z∼ 2 that show evidence of Lyman continuum (LyC) emission based on the newly acquired UV imaging of the Hubble Deep UV legacy survey (HDUV) conducted with the WFC3/UVIS camera on the Hubble Space Telescope (HST). At the redshift of these sources, the HDUV F275W images partially probe the ionizing continuum. By exploiting…
Disruption of Saturn's quasi-periodic equatorial oscillation by the great northern storm
Fletcher, Leigh N.; Irwin, Patrick G. J.; Flasar, F. Michael +7 more
The equatorial middle atmospheres of the Earth1, Jupiter2 and Saturn3,4 all exhibit a remarkably similar phenomenon—a vertical, cyclic pattern of alternating temperatures and zonal (east-west) wind regimes that propagate slowly downwards with a well-defined multi-year period. Earth's quasi-biennial oscillation (QBO…
Galactic winds with MUSE: A direct detection of Fe II* emission from a z = 1.29 galaxy
Bacon, Roland; Finley, Hayley; Bouché, Nicolas +13 more
Emission signatures from galactic winds provide an opportunity to directly map the outflowing gas, but this is traditionally challenging because of the low surface brightness. Using very deep observations (27 h) of the Hubble Deep Field South with the Multi Unit Spectroscopic Explorer (MUSE) instrument, we identify signatures of an outflow in both…
Staying away from the bar: the local dynamical signature of slow and fast bars in the Milky Way
Siebert, Arnaud; Famaey, Benoit; Bienaymé, Olivier +3 more
Both the three-dimensional density of red clump giants and the gas kinematics in the inner Galaxy indicate that the pattern speed of the Galactic bar could be much lower than previously estimated. Here, we show that such slow bar models are unable to reproduce the bimodality observed in local stellar velocity space. We do so by computing the respo…
Formation of Methylamine and Ethylamine in Extraterrestrial Ices and Their Role as Fundamental Building Blocks of Proteinogenic α-amino Acids
Kaiser, Ralf I.; Förstel, Marko; Bergantini, Alexandre +2 more
The -CH-NH2 moiety represents the fundamental building block of all proteinogenic amino acids, with the cyclic amino acid proline being a special case (-CH-NH- in proline). Exploiting a chemical retrosynthesis, we reveal that methylamine (CH3NH2) and/or ethylamine (CH3CH2NH2) are es…
Powerful outflows in the central parsecs of the low-luminosity active galactic nucleus NGC 1386
Prieto, M. A.; Luque, R.; Müller-Sánchez, F. +3 more
Low-luminosity active galactic nuclei, I.e. L_{bol}/Ledd ∼ 10-6-10-3, constitute the bulk population of active galactic nuclei (AGNs). Powerful jets, common in these objects, are a crucial source of feedback energy-driving mass outflows into the host galaxy and the intergalactic medium. This paper reports the first…