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Planck intermediate results. XVIII. The millimetre and sub-millimetre emission from planetary nebulae
Miville-Deschênes, M. -A.; Bernard, J. -P.; Planck Collaboration +158 more
Late stages of stellar evolution are characterized by copious mass-loss events whose signature is the formation of circumstellar envelopes (CSE). Planck multi-frequency measurements have provided relevant information on a sample of Galactic planetary nebulae (PNe) in the important and relatively unexplored observational band between 30 and 857 GHz…
Multipoint observations of plasma phenomena made in space by Cluster
Perri, S.; Pickett, J. S.; Sahraoui, F. +11 more
Plasmas are ubiquitous in nature, surround our local geospace environment, and permeate the universe. Plasma phenomena in space give rise to energetic particles, the aurora, solar flares and coronal mass ejections, as well as many energetic phenomena in interstellar space. Although plasmas can be studied in laboratory settings, it is often difficu…
Flapping motions of the magnetotail current sheet excited by nonadiabatic ions
Dandouras, I.; Rème, H.; Cao, J. B. +3 more
Observations by the Cluster spacecraft on 3 August 2004 are presented as an example of flapping motions of the magnetotail current sheet excited by nonadiabatic ions. It is found that the current sheet up-down motions are exactly corresponding to alternating hemispherical asymmetries of the bouncing ion population. We show that those hemisphere-as…
The solar oxygen abundance from an empirical three-dimensional model
Socas-Navarro, H.
The oxygen abundance in the solar photosphere, and consequently the solar metallicity itself, is still a controversial question with far-reaching implications in many areas of astrophysics. This paper presents a new determination obtained by fitting the forbidden O i line at 6300 Å with an observational 3D model. The approach presented here is nov…
Constraining Very High Mass Population III Stars through He II Emission in Galaxy BDF-521 at z = 7.01
Fan, Xiaohui; Jiang, Linhua; Cai, Zheng +4 more
Numerous theoretical models have long proposed that a strong He II λ1640 emission line is the most prominent and unique feature of massive Population III (Pop III) stars in high-redshift galaxies. The He II λ1640 line strength can constrain the mass and initial mass function (IMF) of Pop III stars. We use F132N narrowband filter on the Hubble Spac…
Herschel PACS and SPIRE spectroscopy of the photodissociation regions associated with S 106 and IRAS 23133+6050
Wolfire, M. G.; Tielens, A. G. G. M.; Boersma, C. +4 more
Context. Photodissociation regions (PDRs) contain a large portion of all of the interstellar matter in galaxies. Classical examples include the boundaries between ionized regions and molecular clouds in regions of massive star-formation, marking the point where all of the photons that are energetic enough to ionize hydrogen have been absorbed.
3D Electron Density Distributions in the Solar Corona during Solar Minima: Assessment for More Realistic Solar Wind Modeling
Riley, Pete; Foullon, Claire; de Patoul, Judith
Knowledge of the electron density distribution in the solar corona put constraints on the magnetic field configurations for coronal modeling and on initial conditions for solar wind modeling. We work with polarized SOHO/LASCO-C2 images from the last two recent minima of solar activity (1996-1997 and 2008-2010), devoid of coronal mass ejections. Th…
Origin and Evolution of Plasmoids and Flux Ropes in the Magnetotails of Earth and Mars
Eastwood, J. P.; Kiehas, S. A.
This chapter discusses the origin and evolution of plasmoids and flux ropes in Earth's magnetotail, providing an overview of author's current understanding based on recent multipoint and multimission data analysis. It also presents recent results concerning observations of flux ropes in the vicinity of Mars. Understanding the Mars solar wind inter…
The EUV spectrum of the Sun: Irradiances during 1998-2014
Andretta, V.; Del Zanna, G.
We present calibrated EUV spectral irradiances obtained from observations with the Solar and Heliospheric Observatory (SOHO) Coronal Diagnostics Spectrometer (CDS) Normal Incidence Spectrometer (NIS) during the 1998-2014 period, which spans the cycle 23 maximum and minimum and the cycle 24 maximum. We revise the corrections for the burn-in of the …
Radial and Azimuthal Oscillations of Halo Coronal Mass Ejections in the Sun
Moon, Y. -J.; Lee, Harim; Nakariakov, V. M.
We present the first observational detection of radial and azimuthal oscillations in full halo coronal mass ejections (HCMEs). We analyze nine HCMEs well-observed by the Large Angle and Spectrometric Coronagraph (LASCO) from 2011 February to June. Using the LASCO C3 running difference images, we estimated the instantaneous apparent speeds of the H…