Search Publications
Supernova 1987A: a Template to Link Supernovae to Their Remnants
Miceli, M.; Bocchino, F.; Orlando, S. +1 more
The emission of supernova remnants (SNRs) reflects the properties of both the progenitor supernovae (SNe) and the surrounding environment. The complex morphology of the remnants, however, hampers the disentanglement of the two contributions. Here, we aim at identifying the imprint of SN 1987A on the X-ray emission of its remnant and at constrainin…
Evolution of the ion environment of comet 67P/Churyumov-Gerasimenko. Observations between 3.6 and 2.0 AU
Kallio, E.; Fedorov, A.; Koskinen, H. +28 more
Context. The Rosetta spacecraft is escorting comet 67P/Churyumov-Gerasimenko from a heliocentric distance of >3.6 AU, where the comet activity was low, until perihelion at 1.24 AU. Initially, the solar wind permeates the thin comet atmosphere formed from sublimation.
Aims: Using the Rosetta Plasma Consortium Ion Composition Analyzer (RPC-I…
Dense cloud cores revealed by CO in the low metallicity dwarf galaxy WLM
Brinks, Elias; Elmegreen, Bruce G.; Rubio, Monica +3 more
Understanding stellar birth requires observations of the clouds in which they form. These clouds are dense and self-gravitating, and in all existing observations they are molecular, with H2 the dominant species and carbon monoxide (CO) the best available tracer. When the abundances of carbon and oxygen are low compared with that of hydr…
Spatial distribution of low-energy plasma around comet 67P/CG from Rosetta measurements
Glassmeier, K. -H.; Szego, K.; Nilsson, H. +22 more
We use measurements from the Rosetta plasma consortium Langmuir probe and mutual impedance probe to study the spatial distribution of low-energy plasma in the near-nucleus coma of comet 67P/Churyumov-Gerasimenko. The spatial distribution is highly structured with the highest density in the summer hemisphere and above the region connecting the two …
IRIS Si IV Line Profiles: An Indication for the Plasmoid Instability during Small-scale Magnetic Reconnection on the Sun
Innes, D. E.; Huang, Y. -M.; Guo, L. -J. +1 more
Our understanding of the process of fast reconnection has undergone a dramatic change in the last 10 years driven, in part, by the availability of high-resolution numerical simulations that have consistently demonstrated the break-up of current sheets into magnetic islands, with reconnection rates that become independent of Lundquist number, chall…
Peering through the holes: the far-UV color of star-forming galaxies at z ~ 3-4 and the escaping fraction of ionizing radiation
Schaerer, D.; Giavalisco, M.; Castellano, M. +11 more
Aims: We aim to investigate the effect of the escaping ionizing radiation on the color selection of high-redshift galaxies and identify candidate Lyman-continuum (LyC) emitters.
Methods: We used the intergalactic medium (IGM) prescription of Inoue et al. (2014, MNRAS, 442, 1805) and galaxy synthesis models of Bruzual & Charlot (2003,…
A novel scenario for the possible X-ray line feature at ~3.5 keV. Charge exchange with bare sulfur ions
Raassen, A. J. J.; Gu, L.; Kaastra, J. +4 more
Motivated by recent claims of a compelling ~3.5 keV emission line from nearby galaxies and galaxy clusters, we investigate a novel plasma model incorporating a charge exchange component obtained from theoretical scattering calculations. Fitting this kind of component with a standard thermal model yields positive residuals around 3.5 keV, produced …
Detection of two power-law tails in the probability distribution functions of massive GMCs.
Abergel, A.; Hill, T.; Arzoumanian, D. +20 more
We report the novel detection of complex high column density tails in the probability distribution functions (PDFs) for three high-mass star-forming regions (CepOB3, MonR2, NGC 6334), obtained from dust emission observed with Herschel. The low column density range can be fitted with a lognormal distribution. A first power-law tail starts above an …
A Multiwavelength Study of the Relativistic Tidal Disruption Candidate Swift J2058.4+0516 at Late Times
Fruchter, Andrew S.; Filippenko, Alexei V.; Cenko, S. Bradley +12 more
We report a multiwavelength (X-ray, ultraviolet/optical/infrared (UVOIR), radio) analysis of the relativistic tidal disruption event (TDE) candidate Sw J2058+05 from 3 months to 3 yr post-discovery in order to study its properties and compare its behavior with that of Sw J1644+57. Our main results are as follows: (1) The long-term X-ray light curv…
The Metagalactic Ionizing Background: A Crisis in UV Photon Production or Incorrect Galaxy Escape Fractions?
Shull, J. Michael; Danforth, Charles W.; Tilton, Evan M. +1 more
Recent suggestions of a “photon underproduction crisis” have generated concern over the intensity and spectrum of ionizing photons in the metagalactic ultraviolet background (UVB). The balance of hydrogen photoionization and recombination determines the opacity of the low-redshift intergalactic medium (IGM). We calibrate the hydrogen photoionizati…