Search Publications
Molecular Hydrogen Absorption from the Halo of a z ∼ 0.4 Galaxy
Charlton, Jane C.; Kacprzak, Glenn G.; Churchill, Christopher W. +1 more
Lyman- and Werner-band absorption of molecular hydrogen ({{{H}}}2) is detected in ∼50% of low-redshift (z\lt 1) DLAs/sub-DLAs with N({{{H}}}2) \gt {10}14.4 cm-2. However, the true origin(s) of the {{{H}}}2-bearing gas remain elusive. Here we report a new detection of an {{{H}}}2 abs…
Hubble Space Telescope observations of the host galaxies and environments of calcium-rich supernovae
Lyman, J. D.; Angus, C. R.; Davies, M. B. +4 more
Calcium-rich supernovae (SNe) represent a significant challenge for our understanding of the fates of stellar systems. They are less luminous than other SN types and they evolve more rapidly to reveal nebular spectra dominated by strong calcium lines with weak or absent signatures of other intermediate- and iron-group elements, which are seen in o…
Modeling the Solar Wind at the Ulysses, Voyager, and New Horizons Spacecraft
McComas, D. J.; Pogorelov, N. V.; Zank, G. P. +2 more
The outer heliosphere is a dynamic region shaped largely by the interaction between the solar wind and the interstellar medium. While interplanetary magnetic field and plasma observations by the Voyager spacecraft have significantly improved our understanding of this vast region, modeling the outer heliosphere still remains a challenge. We simulat…
Conditions for electron-cyclotron maser emission in the solar corona
Bloomfield, D. S.; Zucca, P.; Gallagher, P. T. +1 more
Context. The Sun is an active source of radio emission ranging from long duration radio bursts associated with solar flares and coronal mass ejections to more complex, short duration radio bursts such as solar S bursts, radio spikes and fibre bursts. While plasma emission is thought to be the dominant emission mechanism for most radio bursts, the …
Broadband Observations of High Redshift Blazars
Stalin, C. S.; Fabian, A. C.; Parker, M. L. +1 more
We present a multi-wavelength study of four high redshift blazars, S5 0014+81 (z = 3.37), CGRaBS J0225+1846 (z = 2.69), BZQ J1430+4205 (z = 4.72), and 3FGL J1656.2-3303 (z = 2.40) using quasi-simultaneous data from the Swift, Nuclear Spectroscopic Telescope Array (NuSTAR) and the Fermi-Large Area Telescope (LAT) and also archival XMM-Newton observ…
The missing satellite problem in 3D
Treu, T.; Torrey, Paul; Lu, Y. +3 more
It is widely believed that the large discrepancy between the observed number of satellite galaxies and the predicted number of dark subhaloes can be resolved via a variety of baryonic effects which suppress star formation in low-mass haloes. Supporting this hypothesis, numerous high-resolution simulations with star formation and associated feedbac…
Massive stars dying alone: the extremely remote environment of SN 2009ip
Smith, Nathan; Andrews, Jennifer E.; Mauerhan, Jon C.
We present late-time Hubble Space Telescope (HST) images of the site of supernova (SN) 2009ip taken almost 3 yr after its bright 2012 luminosity peak. SN 2009ip is now slightly fainter in broad filters than the progenitor candidate detected by HST in 1999. The current source continues to be dominated by ongoing late-time circumstellar material int…
The Reverberation Lag in the Low-mass X-ray Binary H1743-322
Ponti, Gabriele; De Marco, Barbara
The evolution of the inner accretion flow of a black hole X-ray binary during an outburst is still a matter of active research. X-ray reverberation lags are powerful tools for constraining disk-corona geometry. We present a study of X-ray lags in the black hole transient H1743-322. We compared the results obtained from analysis of all the publicly…
The MUSE view of QSO PG 1307+085: an elliptical galaxy on the MBH-σ* relation interacting with its group environment
Scharwächter, J.; Husemann, B.; Bennert, V. N. +2 more
We report deep optical integral-field spectroscopy with the Multi-Unit Spectroscopic Explorer (MUSE) at the Very Large Telescope of the luminous radio-quiet quasi-stellar object (QSO) PG 1307+085 obtained during commissioning. Given the high sensitivity and spatial resolution delivered by MUSE, we are able to resolve the compact (re ∼ 1…
Radical-induced chemistry from VUV photolysis of interstellar ice analogues containing formaldehyde
Danger, Grégoire; Chiavassa, Thierry; Duvernay, Fabrice +1 more
Surface processes and radical chemistry within interstellar ices are increasingly suspected to play an important role in the formation of complex organic molecules (COMs) observed in several astrophysical regions and cometary environments. We present new laboratory experiments on the low-temperature solid state formation of complex organic molecul…