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The merger Seyfert galaxy Arp 220: line and continuum absorption and emission

Contini, M.

The line and continuum spectra of the merger galaxy Arp 220 are analysed with the aim of investigating the ionizing and heating sources. We refer to radio, optical, infrared and X-ray spectra. The results show that in agreement with other merger galaxies, the optical lines are emitted from gas photoionized by the active galactic nucleus (AGN) and …

Hot gas, cold gas and sub-haloes in a Lyman α blob at redshift 2.38

Scarlata, Claudia; Dopita, Michael A.; Woodgate, Bruce E. +5 more

We present integral field spectroscopy of a Lyman α blob at redshift 2.38, with a spectral resolution three times better than previous published work. As with previous observations, the blob has a chaotic velocity structure, much of which breaks up into multiple components. Our spectroscopy shows, however, that some of these multiple components ar…

Cold Dust but Warm Gas in the Unusual Elliptical Galaxy NGC 4125

Clements, D. L.; Ciesla, L.; Boquien, M. +19 more

Data from the Herschel Space Observatory have revealed an unusual elliptical galaxy, NGC 4125, which has strong and extended submillimeter emission from cold dust but only very strict upper limits to its CO and H I emission. Depending on the dust emissivity, the total dust mass is 2-5 × 10⁶ M _⊙. While the neutral gas-to-dust …

Hemispheric Asymmetries in the Polar Solar Wind Observed by Ulysses near the Minima of Solar Cycles 22 and 23

McComas, D. J.; Pogorelov, N. V.; Desai, M. I. +2 more

We examined solar wind plasma and interplanetary magnetic field (IMF) observations from Ulysses' first and third orbits to study hemispheric differences in the properties of the solar wind and IMF originating from the Sun's large polar coronal holes (PCHs) during the declining and minimum phase of solar cycles 22 and 23. We identified hemispheric …

Herschel-ATLAS/GAMA: What determines the far-infrared properties of radio galaxies?

de Zotti, G.; Cooray, A.; Ibar, E. +20 more

We perform a stacking analysis of Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) data in order to obtain isothermal dust temperatures and rest-frame luminosities at 250 µm (L₂₅₀), for a well-defined sample of 1599 radio sources over the H-ATLAS Phase 1/Galaxy and Mass Assembly (GAMA) area. The radio sample is generat…

Long-term evolution of the neutron-star spin period of SXP 1062

Haberl, F.; Udalski, A.; Gallagher, J. S. +4 more

Context. The Be/X-ray binary SXP 1062 is of especial interest owing to the large spin period of the neutron star, its large spin-down rate, and the association with a supernova remnant constraining its age. This makes the source an important probe for accretion physics.
Aims: To investigate the long-term evolution of the spin period and assoc…

Binary Frequencies in a Sample of Globular Clusters. I. Methodology and Initial Results

Bregman, Joel N.; Ji, Jun

Binary stars are thought to be a controlling factor in globular cluster evolution, since they can heat the environmental stars by converting their binding energy to kinetic energy during dynamical interactions. Through such interaction, the binaries determine the time until core collapse. To test predictions of this model, we have determined binar…

Nonlinear interaction of kinetic Alfvén wave with fast magnetosonic wave and turbulent spectrum

Sharma, R. P.; Modi, K. V.

In the present paper, authors have investigated nonlinear interaction of kinetic Alfvén wave (KAW) and fast magnetosonic wave for intermediate β-plasma (m_e/m_i≪β ≪1). Authors have developed the set of dimensionless equations in the presence of ponderomotive nonlinearity due to KAW in the dynamics of fast magnetosonic wave. Num…

Planetary Magnetic Fields and Climate Evolution

Luhmann, J. G.; Leblanc, F.; Brain, D. A. +2 more

Astrometry and Orbits of Nix, Kerberos, and Hydra

Buie, Marc W.; Grundy, William M.; Tholen, David J.

We present new Hubble Space Telescope observations of three of Pluto's outer moons, Nix, Kerberos, and Hydra. This work revises previously published astrometry of Nix and Hydra from 2002 to 2003. New data from a four-month span during 2007 include observations designed to better measure the positions of Nix and Hydra. A third data set from 2010 al…