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Anatomy of the AGN in NGC 5548. IV. The short-term variability of the outflows
Kaastra, J. S.; Kriss, G. A.; Bianchi, S. +16 more
During an extensive multiwavelength campaign that we performed in 2013-2014, we found the prototypical Seyfert 1 galaxy NGC 5548 in an unusual condition of heavy and persistent obscuration. The newly discovered "obscurer" absorbs most of the soft X-ray continuum along our line of sight and lowers the ionizing luminosity received by the classical w…
Coronal Sources and In Situ Properties of the Solar Winds Sampled by ACE During 1999 - 2008
Li, Xing; Fu, Hui; Li, Bo +4 more
We identify the coronal sources of the solar winds sampled by the ACE spacecraft during 1999 - 2008 and examine the in situ solar wind properties as a function of wind sources. The standard two-step mapping technique is adopted to establish the photospheric footpoints of the magnetic flux tubes along which the ACE winds flow. The footpoints are th…
Molecular ions in the O-rich evolved star OH231.8+4.2: HCO+, H13CO+ and first detection of SO+, N2H+, and H3O+
Menten, K. M.; Sánchez Contreras, C.; Alcolea, J. +8 more
OH 231.8+4.2, a bipolar outflow around a Mira-type variable star, displays a unique molecular richness amongst circumstellar envelopes (CSEs) around O-rich AGB and post-AGB stars. We report line observations of the HCO+ and H13CO+ molecular ions and the first detection of SO+, N2H+,…
The first pre-supersoft X-ray binary
Bayo, A.; Gänsicke, B. T.; Pala, A. F. +8 more
We report the discovery of an extremely close white dwarf plus F dwarf main-sequence star in a 12 h binary identified by combining data from the Radial Velocity Experiment survey and the Galaxy Evolution Explorer survey. A combination of spectral energy distribution fitting and optical and Hubble Space Telescope ultraviolet spectroscopy allowed us…
Evidence of Twisted Flux-Tube Emergence in Active Regions
Mandrini, C. H.; Démoulin, P.; López Fuentes, M. +1 more
Elongated magnetic polarities are observed during the emergence phase of bipolar active regions (ARs). These extended features, called magnetic tongues, are interpreted as a consequence of the azimuthal component of the magnetic flux in the toroidal flux-tubes that form ARs. We develop a new systematic and user-independent method to identify AR to…
Optical Identification of He White Dwarfs Orbiting Four Millisecond Pulsars in the Globular Cluster 47 Tucanae
Dalessandro, E.; Salaris, M.; Ferraro, F. R. +4 more
We used ultra-deep UV observations obtained with the Hubble Space Telescope to search for optical companions to binary millisecond pulsars (MSPs) in the globular cluster 47 Tucanae. We identified four new counterparts (to MSPs 47TucQ, 47TucS, 47TucT, and 47TucY) and confirmed those already known (to MSPs 47TucU and 47TucW). In the color-magnitude …
Equatorial noise emissions with quasiperiodic modulation of wave intensity
Pickett, J. S.; Santolík, O.; Němec, F. +2 more
Equatorial noise (EN) emissions are electromagnetic wave events at frequencies between the proton cyclotron frequency and the lower hybrid frequency observed in the equatorial region of the inner magnetosphere. They propagate nearly perpendicular to the ambient magnetic field, and they exhibit a harmonic line structure characteristic of the proton…
First High-resolution Spectroscopic Observations of an Erupting Prominence Within a Coronal Mass Ejection by the Interface Region Imaging Spectrograph (IRIS)
Liu, Wei; Antolin, Patrick; De Pontieu, Bart +6 more
Spectroscopic observations of prominence eruptions associated with coronal mass ejections (CMEs), although relatively rare, can provide valuable plasma and three-dimensional geometry diagnostics. We report the first observations by the Interface Region Imaging Spectrograph mission of a spectacular fast CME/prominence eruption associated with an eq…
Comparing Planck and WMAP: Maps, Spectra, and Parameters
Larson, D.; Weiland, J. L.; Hinshaw, G. +1 more
We examine the consistency of the 9 yr WMAP data and the first-release Planck data. We specifically compare sky maps, power spectra, and the inferred Λ cold dark matter (ΛCDM) cosmological parameters. Residual dipoles are seen in the WMAP and Planck sky map differences, but their amplitudes are consistent within the quoted uncertainties, and they …
Solar Cycle Variation of the Inter-network Magnetic Field
Wang, Jingxiu; Jin, Chunlan
The solar inter-network magnetic field is the weakest component of solar magnetism, but it contributes most of the solar surface magnetic flux. The study of its origin has been constrained by the inadequate tempospatial resolution and sensitivity of polarization observations. With dramatic advances in spatial resolution and detecting sensitivity, …