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The Global Solar Dynamo
Cameron, R. H.; Dikpati, M.; Brandenburg, A.
A brief summary of the various observations and constraints that underlie solar dynamo research are presented. The arguments that indicate that the solar dynamo is an alpha-omega dynamo of the Babcock-Leighton type are then shortly reviewed. The main open questions that remain are concerned with the subsurface dynamics, including why sunspots emer…
ALMA reveals starburst-like interstellar medium conditions in a compact star-forming galaxy at z 2 using [CI] and CO
van Dokkum, Pieter G.; Nelson, Erica J.; De Breuck, Carlos +9 more
We present ALMA detections of the [CI] 1-0, CO J = 3-2, and CO J = 4-3 emission lines, as well as the ALMA band 4 continuum for a compact star-forming galaxy (cSFG) at z = 2.225, 3D-HST GS30274. As is typical for cSFGs, this galaxy has a stellar mass of 1.89 ± 0.47 × 1011M⊙, with a star formation rate (SFR) of 214 ± 44 M…
Weighing neutrinos in the scenario of vacuum energy interacting with cold dark matter: application of the parameterized post-Friedmann approach
Zhang, Jing-Fei; Zhang, Xin; Li, Yun-He +1 more
We constrain the neutrino mass in the scenario of vacuum energy interacting with cold dark matter by using current cosmological observations. To avoid the large-scale instability problem in interacting dark energy models, we employ the parameterized post-Friedmann (PPF) approach to do the calculation of perturbation evolution, for the Q = βHρ…
Internal delensing of Planck CMB temperature and polarization
Challinor, Anthony; Carron, Julien; Lewis, Antony
We present a first internal delensing of CMB maps, both in temperature and polarization, using the public foreground-cleaned (SMICA) Planck 2015 maps. After forming quadratic estimates of the lensing potential, we use the corresponding displacement field to undo the lensing on the same data. We build differences of the delensed spectra to the orig…
Tomographic reflection modelling of quasi-periodic oscillations in the black hole binary H 1743-322
Ingram, Adam; Middleton, Matthew; Altamirano, Diego +2 more
Accreting stellar mass black holes (BHs) routinely exhibit Type-C quasi-periodic oscillations (QPOs). These are often interpreted as Lense-Thirring precession of the inner accretion flow, a relativistic effect whereby the spin of the BH distorts the surrounding space-time, inducing nodal precession. The best evidence for the precession model is th…
The Progenitor and Early Evolution of the Type IIb SN 2016gkg
Lundqvist, P.; Gal-Yam, A.; Smith, M. +24 more
We report initial observations and analysis on the Type IIb SN 2016gkg in the nearby galaxy NGC 613. SN 2016gkg exhibited a clear double-peaked light curve during its early evolution, as evidenced by our intensive photometric follow-up campaign. SN 2016gkg shows strong similarities with other Type IIb SNe, in particular, with respect to the He I e…
Two-dimensional Radiative Magnetohydrodynamic Simulations of Partial Ionization in the Chromosphere. II. Dynamics and Energetics of the Low Solar Atmosphere
Martínez-Sykora, Juan; De Pontieu, Bart; Nóbrega-Siverio, Daniel +3 more
We investigate the effects of interactions between ions and neutrals on the chromosphere and overlying corona using 2.5D radiative MHD simulations with the Bifrost code. We have extended the code capabilities implementing ion-neutral interaction effects using the generalized Ohm’s law, I.e., we include the Hall term and the ambipolar diffusion (Pe…
A study of the sensitivity of shape measurements to the input parameters of weak-lensing image simulations
Hoekstra, Henk; Viola, Massimo; Herbonnet, Ricardo
Improvements in the accuracy of shape measurements are essential to exploit the statistical power of planned imaging surveys that aim to constrain cosmological parameters using weak lensing by large-scale structure. Although a range of tests can be performed using the measurements, the performance of the algorithm can only be quantified using simu…
AGN Populations in Large-volume X-Ray Surveys: Photometric Redshifts and Population Types Found in the Stripe 82X Survey
Kirkpatrick, Allison; Nandra, Kirpal; Marchesi, Stefano +16 more
Multiwavelength surveys covering large sky volumes are necessary to obtain an accurate census of rare objects such as high-luminosity and/or high-redshift active galactic nuclei (AGNs). Stripe 82X is a 31.3 X-ray survey with Chandra and XMM-Newton observations overlapping the legacy Sloan Digital Sky Survey Stripe 82 field, which has a rich invest…
The GOODS-N Jansky VLA 10 GHz Pilot Survey: Sizes of Star-forming µJY Radio Sources
Dickinson, Mark; Weiner, Benjamin J.; Inami, Hanae +5 more
Our sensitive ({σ }{{n}}≈ 572 {nJy} {{beam}}-1), high-resolution (FWHM {θ }1/2=0\buildrel{\prime\prime}\over{.} 22≈ 2 {kpc} {at} z≳ 1), 10 GHz image covering a single Karl G. Jansky Very Large Array (VLA) primary beam (FWHM {{{\Theta }}}1/2≈ 4\buildrel{ \prime}\over{.} 25) in the GOODS-N field contains 3…