Search Publications
The coronal energy input from magnetic braiding
Yeates, A. R.; Welsch, B. T.; Bianchi, F. +1 more
We estimate the energy input into the solar corona from photospheric footpoint motions, using observations of a plage region by the Hinode Solar Optical Telescope. Assuming a perfectly ideal coronal evolution, two alternative lower bounds for the Poynting flux are computed based on field line footpoint trajectories, without requiring horizontal ma…
Evolution and Dynamics of Orphan Penumbrae in the Solar Photosphere: Analysis from Multi-instrument Observations
Guglielmino, Salvo L.; Romano, Paolo; Zuccarello, Francesca
We investigate the dynamics and magnetic properties of orphan penumbrae observed in the solar photosphere to understand the formation process of such structures. We observed two orphan penumbrae in active region NOAA 11089 during a coordinated observing campaign carried out in 2010 July, involving the Hinode/Solar Optical Telescope (SOT) and Dutch…
The Herschel Virgo Cluster Survey - XVI. A cluster inventory
Bianchi, S.; Fritz, J.; De Looze, I. +12 more
Herschel far-infrared (FIR) observations are used to construct Virgo cluster galaxy luminosity functions and to show that the cluster lacks the very bright and the numerous faint sources detected in field galaxy surveys. The FIR spectral energy distributions are fitted to obtain dust masses and temperatures and the dust mass function. The cluster …
The Mass Distribution of the Strong Lensing Cluster SDSS J1531+3414
Rigby, Jane R.; Sharon, Keren; Johnson, Traci L. +5 more
We present the mass distribution at the core of SDSS J1531+3414, a strong-lensing cluster at z = 0.335. We find that the mass distribution is well described by two cluster-scale halos with a contribution from cluster-member galaxies. New Hubble Space Telescope observations of SDSS J1531+3414 reveal a signature of ongoing star formation associated …
Widespread Rotationally Hot Hydronium Ion in the Galactic Interstellar Medium
Godard, B.; Le Petit, F.; Comito, C. +11 more
We present new Herschel observations of the (6,6) and (9,9) inversion transitions of the hydronium ion toward Sagittarius B2(N) and W31C. Sensitive observations toward Sagittarius B2(N) show that the high, ~500 K, rotational temperatures characterizing the population of the highly excited metastable H3O+ rotational levels are…
Tachyon field inflation in light of BICEP2
Nozari, Kourosh; Rashidi, Narges
We study tachyon field inflation in the light of the Planck+WMAP+BICEP2+BAO joint data. While the minimally coupled tachyon field inflation is consistent with the Planck2013 data, it is not confirmed by the Planck+WMAP+BICEP2+BAO data set. However, a nonminimally coupled tachyon field inflation is consistent with this joint data set.
Magnetic fields in the Venus ionosphere: Dependence on the IMF direction—Venus express observations
Woch, J.; Wei, Y.; Zhang, T. L. +2 more
The structure of the magnetized ionosphere of Venus is investigated using the magnetometer and plasma (Analyzer of Space Plasmas and Energetic Atoms 4) data from the Venus Express spacecraft. Observations surveying the low-altitude (h ≤ 250 km) ionosphere were made at solar zenith angles ≥ 75°. The magnetic field permeating the Venus ionosphere at…
Two physical regimes for the giant H II regions and giant molecular clouds in the Antennae galaxies
García-Lorenzo, B.; Gutiérrez, L.; Beckman, J. E. +3 more
We have combined observations of the Antennae galaxies from the radio interferometer ALMA (Atacama Large Millimeter/submillimeter Array) and from the optical interferometer GHαFaS (Galaxy Hα Fabry-Perot System). The two sets of observations have comparable angular and spectral resolutions, enabling us to identify 142 giant molecular clouds (GMCs) …
Solar Photoionization Rates for Interstellar Neutrals in the Inner Heliosphere: H, He, O, and Ne
Bochsler, P.; Kucharek, H.; Möbius, E. +4 more
Extreme UV (EUV) spectra from the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED)/Solar EUV Experiment are used to infer photoionization rates in the inner heliosphere. Relating these rates to various proxies describing the solar EUV radiation, we construct a multi-linear model which allows us to extrapolate ionization rates bac…
Density waves in Titan's upper atmosphere
Yelle, R. V.; Cui, J.; Müller-Wodarg, I. C. F. +2 more
Analysis of the Cassini Ion Neutral Mass Spectrometer data reveals the omnipresence of density waves in various constituents of Titan's upper atmosphere, with quasi-periodical structures visible for N2, CH4,29N2, and some of the minor constituents. The N2 amplitude lies in the range of ≈4%-16%…