Search Publications

Evidence for Three Accreting Black Holes in a Galaxy at z ~ 1.35: A Snapshot of Recently Formed Black Hole Seeds?
DOI: 10.1088/2041-8205/743/2/L37 Bibcode: 2011ApJ...743L..37S

Schawinski, Kevin; Natarajan, Priyamvada; Treister, Ezequiel +3 more

One of the key open questions in cosmology today pertains to understanding when, where, and how supermassive black holes form. While it is clear that mergers likely play a significant role in the growth cycles of black holes, the issue of how supermassive black holes form, and how galaxies grow around them, still needs to be addressed. Here, we pr…

2011 The Astrophysical Journal
eHST 31
Suzaku View of X-Ray Spectral Variability of the Radio Galaxy Centaurus A: Partial Covering Absorber, Reflector, and Possible Jet Component
DOI: 10.1088/0004-637X/743/2/124 Bibcode: 2011ApJ...743..124F

Fukazawa, Yasushi; Ohno, Masanori; Yamazaki, Syoko +6 more

We observed a nearby radio galaxy, Centaurus A (Cen A), three times with Suzaku in 2009 and measured the wide-band X-ray spectral variability more accurately than previous measurements. The Cen A was in an active phase in 2009, and the flux became higher by a factor of 1.5-2.0 and the spectrum became harder than that in 2005. The Fe-K line intensi…

2011 The Astrophysical Journal
Suzaku 31
Cluster X-ray luminosity-temperature relation at z≳ 1.5
DOI: 10.1111/j.1365-2966.2010.18062.x Bibcode: 2011MNRAS.412.2391A

Andreon, S.; Trinchieri, G.; Pizzolato, F.

The evolution of the properties of the hot gas that fills the potential well of galaxy clusters is poorly known, since models are unable to give robust predictions, and observations lack a sufficient redshift leverage and are affected by selection effects. Here, with just two high-redshift, z≈ 1.8, clusters avoiding selection biases, we obtain a s…

2011 Monthly Notices of the Royal Astronomical Society
eHST 31
The Suzaku view of 3C 382
DOI: 10.1088/0004-637X/734/2/105 Bibcode: 2011ApJ...734..105S

Ballo, L.; Reynolds, C. S.; Tombesi, F. +4 more

We present a long (116 ks) Suzaku observation of the broad-line radio galaxy (BLRG) 3C 382 acquired in 2007 April. A Swift BAT spectrum in 15-200 keV from the 58 month survey is also analyzed, together with an archival XMM-Newton EPIC exposure of 20 ks obtained one year after Suzaku. Our main result is the finding with Suzaku of a broad Fe K line …

2011 The Astrophysical Journal
Suzaku XMM-Newton 31
The colour-magnitude relation of elliptical and lenticular galaxies in the ESO Distant Cluster Survey
DOI: 10.1111/j.1365-2966.2010.17445.x Bibcode: 2011MNRAS.410..280J

Aragón-Salamanca, Alfonso; Zaritsky, Dennis; Jablonka, Pascale +4 more

In this paper we study the colour-magnitude relation (CMR) for a sample of 172 morphologically classified elliptical and S0 cluster galaxies from the ESO Distant Cluster Survey (EDisCS) at 0.4 ≲z≲ 0.8. The intrinsic colour scatter about the CMR is very small (<σint>= 0.076) in rest-frame U-V. However, there is a small minority of …

2011 Monthly Notices of the Royal Astronomical Society
eHST 31
Suzaku View of the Swift/BAT Active Galactic Nuclei. IV. Nature of Two Narrow-line Radio Galaxies (3C 403 and IC 5063)
DOI: 10.1088/0004-637X/738/1/70 Bibcode: 2011ApJ...738...70T

Ueda, Yoshihiro; Terashima, Yuichi; Mushotzky, Richard F. +1 more

We report the results of Suzaku broadband X-ray observations of the two narrow-line radio galaxies, 3C 403 and IC 5063. Combined with the Swift/Burst Alert Telescope (BAT) spectra averaged for 58 months, we are able to accurately constrain their spectral properties over the 0.5-200 keV band. The spectra of both nuclei are well represented with an …

2011 The Astrophysical Journal
Suzaku 31
Large-amplitude whistler waves and electron acceleration
DOI: 10.1029/2011GL047893 Bibcode: 2011GeoRL..3812105Y

Yoon, Peter H.

A recent observation shows that large-amplitude whistler waves propagating obliquely with respect to the ambient magnetic field may be responsible for energizing the radiation belt electrons to relativistic energies (MeV) within a time scale as short as a fraction of a second. Test-particle simulations available in the literature invariably adopt …

2011 Geophysical Research Letters
Cluster 31
The extinction map of the OMC-1 molecular cloud behind the Orion nebula
DOI: 10.1051/0004-6361/201116554 Bibcode: 2011A&A...533A..38S

Robberto, M.; Scandariato, G.; Pagano, I. +1 more

Context. The Orion nebula and its associated young stellar cluster are located at the front-side of the optically thick OMC-1 molecular cloud. In order to disentangle the cluster members from background contamination, it is important to know the extinction provided by the OMC-1, which is poorly known, the available measurements …

2011 Astronomy and Astrophysics
eHST 31
Solar cycle evolution of the heliospheric magnetic field: The Ulysses legacy
DOI: 10.1016/j.jastp.2010.03.019 Bibcode: 2011JASTP..73..277S

Smith, E. J.

Important contributions of Ulysses to understanding the solar cycle evolution of the heliospheric magnetic field (HMF) and solar wind are reviewed: a dramatic reorientation of the HMF as the solar dipole rotates between axial and equatorial orientations; solar cycle variation of the total heliospheric magnetic flux and its response to changes in s…

2011 Journal of Atmospheric and Solar-Terrestrial Physics
Ulysses 31
The γ Doradus CoRoT target HD 49434. II. Frequency analysis of the CoRoT data
DOI: 10.1051/0004-6361/201014207 Bibcode: 2011A&A...525A..23C

Auvergne, M.; Amado, P. J.; Baudin, F. +18 more

Context. HD 49434 is a bright (V = 5.75 m) and multiperiodic γ Dor-type pulsator that has been selected for the asteroseismic core programme of the CoRoT satellite.
Aims: An extensive and detailed study has been carried out to investigate the pulsational content of this object on the basis of the 136.9 d (331291 useful datapoints) time series…

2011 Astronomy and Astrophysics
CoRoT 31