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The soft-X-ray emission of Ark 120. XMM-Newton, NuSTAR, and the importance of taking the broad view
Harrison, F. A.; Stern, D.; Zhang, W. W. +17 more
We present simultaneous XMM-Newton and NuSTAR observations of the `bare' Seyfert 1 galaxy, Ark 120, a system in which ionized absorption is absent. The NuSTAR hard-X-ray spectral coverage allows us to constrain different models for the excess soft-X-ray emission. Among phenomenological models, a cutoff power law best explains the soft-X-ray emissi…
Constraints on the star-formation rate of z ~ 3 LBGs with measured metallicity in the CANDELS GOODS-South field
Maiolino, R.; Schaerer, D.; Ferguson, H. C. +19 more
Aims: We aim to constrain the assembly history of high-redshift galaxies and the reliability of UV-based estimates of their physical parameters from an accurate analysis of a unique sample of z ~ 3 Lyman-break galaxies (LBGs).
Methods: We analyse 14 LBGs at z ~ 2.8-3.8 constituting the only sample where both a spectroscopic measurement o…
The formation heights of coronal shocks from 2D density and Alfvén speed maps
Gallagher, Peter T.; Zucca, Pietro; Carley, Eoin P. +1 more
Context. Super-Alfvénic shocks associated with coronal mass ejections (CMEs) can produce radio emission known as Type II bursts. In the absence of direct imaging, accurate estimates of coronal electron densities, magnetic field strengths, and Alfvén speeds are required to calculate the kinematics of shocks. To date, 1D radial models have been used…
Linking Lyα and Low-ionization Transitions at Low Optical Depth
Oey, M. S.; Jaskot, A. E.
We suggest that low optical depth in the Lyman continuum (LyC) may relate the Lyα emission, C II and Si II absorption, and C II* and Si II* emission seen in high-redshift galaxies. We base this analysis on Hubble Space Telescope Cosmic Origins Spectrograph spectra of four Green Pea (GP) galaxies, which may be analogs of z > 2 Lyα emitters (LAEs…
A Calibration of the Stellar Mass Fundamental Plane at z ~ 0.5 Using the Micro-lensing-induced Flux Ratio Anomalies of Macro-lensed Quasars
Schechter, Paul L.; Pooley, David; Blackburne, Jeffrey A. +1 more
We measure the stellar mass surface densities of early-type galaxies by observing the micro-lensing of macro-lensed quasars caused by individual stars, including stellar remnants, brown dwarfs, and red dwarfs too faint to produce photometric or spectroscopic signatures. Instead of observing multiple micro-lensing events in a single system, we comb…
The rotation state of 67P/Churyumov-Gerasimenko from approach observations with the OSIRIS cameras on Rosetta
Jorda, L.; Lamy, P. L.; Bertaux, J. -L. +46 more
Aims: Approach observations with the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) experiment onboard Rosetta are used to determine the rotation period, the direction of the spin axis, and the state of rotation of comet 67P's nucleus.
Methods: Photometric time series of 67P have been acquired by OSIRIS since the pos…
Herschel Observations of Extraordinary Sources: Analysis of the Full Herschel/HIFI Molecular Line Survey of Sagittarius B2(N)
Vasyunina, Tatiana; McGuire, Brett A.; Bergin, Edwin A. +18 more
A sensitive broadband molecular line survey of the Sagittarius B2(N) star-forming region has been obtained with the Heterodyne Instrument for the Far-Infrared (HIFI) instrument on the Herschel Space Observatory, offering the first high spectral resolution look at this well-studied source in a wavelength region largely inaccessible from the ground …
Consequences of geomagnetic activity on energization and loss of radiation belt electrons by oblique chorus waves
Krasnoselskikh, V.; Artemyev, A. V.; Agapitov, O. V. +1 more
Statistics of amplitudes and obliquity of lower band chorus whistler mode waves have been obtained from Cluster measurements in Earth's outer radiation belt and fitted as functions of L, latitude, magnetic local time, and three geomagnetic activity ranges for Dst∈[+10,-80] nT. Very oblique chorus waves have generally a much smaller average intensi…
New Insights into the Physical Nature of Coronal Mass Ejections and Associated Shock Waves within the Framework of the Three-dimensional Structure
Zhang, Jie; Kwon, Ryun-Young; Olmedo, Oscar
We present new insights into the physical nature of coronal mass ejections (CMEs) and associated shock waves within the framework of the three-dimensional (3D) structure. We have developed a compound model in order to determine the 3D structure of multiple fronts composing a CME, using data sets taken from STEREO, SDO, and SOHO. We applied the met…
Closing the loop: a self-consistent model of optical, X-ray and Sunyaev-Zel'dovich scaling relations for clusters of Galaxies
Bartlett, J. G.; Rykoff, E. S.; Evrard, A. E. +1 more
We demonstrate that optical data from Sloan Digital Sky Survey, X-ray data from ROSAT and Chandra, and Sunyaev-Zel'dovich (SZ) data from Planck can be modelled in a fully self-consistent manner. After accounting for systematic errors and allowing for property covariance, we find that scaling relations derived from optical and X-ray selected cluste…