Search Publications
Precise Timing of the X-ray Pulsar 1E 1207.4-5209: A Steady Neutron Star Weakly Magnetized at Birth
Gotthelf, E. V.; Halpern, J. P.
We analyze all X-ray timing data on 1E 1207.4-5209 in supernova remnant PKS 1209-51/52 gathered from 1993-2005 and find a highly stable rotation with P=424.130749(4) ms and P˙=(6.6+/-9.0)×10-17 (1 σ errors). This refutes previous claims of large timing irregularities in these data. In the dipole spin-down formalism, the 2 σ upper limit …
Cassini Ion and Neutral Mass Spectrometer data in Titan's upper atmosphere and exosphere: Observation of a suprathermal corona
Luhmann, J. G.; Johnson, R. E.; Leblanc, F. +10 more
The neutral nitrogen and methane measurements made by Ion and Neutral Mass Spectrometer during Cassini flybys TA, TB, and T5 in Titan's upper atmosphere and exosphere are presented. Large horizontal variations are observed in the total density, recorded to be twice as large during TA as during T5
A CFH12k lensing survey of X-ray luminous galaxy clusters. II. Weak lensing analysis and global correlations
Smail, I.; Kneib, J. -P.; Smith, G. P. +5 more
Aims:We present a wide-field multi-color survey of a homogeneous sample of eleven clusters of galaxies for which we measure total masses and mass distributions from weak lensing. This sample, spanning a small range in both X-ray luminosity and redshift, is ideally suited to determining the normalisation of scaling relations between X-ray propertie…
Could we identify hot ocean-planets with CoRoT, Kepler and Doppler velocimetry?
Sotin, C.; Barge, P.; Bordé, P. +16 more
Planets less massive than about 10 M are expected to have no massive H-He atmosphere and a cometary composition (∼50% rocks, 50% water, by mass) provided they formed beyond the snowline of protoplanetary disks. Due to inward migration, such planets could be found at any distance between their formation site and the star. If migration stops within …
Titan's young surface: Initial impact crater survey by Cassini RADAR and model comparison
Lorenz, R. D.; Anderson, Y. Z.; Lunine, J. I. +9 more
Cassini's Radar instrument has mapped over 10% of Titan's surface through the T18 flyby in August 2006 and has detected remarkably few impact craters. Three impact craters have been conclusively identified and named, and a handful of unconfirmed candidate impact structures are documented. These results indicate that the overall crater density is a…
Revealing the High Energy Emission from the Obscured Seyfert Galaxy MCG-5-23-16 with Suzaku
Kunieda, Hideyo; Okajima, Takashi; Yaqoob, Tahir +19 more
We report on a 100ks Suzaku observation of the bright, nearby (z=0.008486) Seyfert 1.9 galaxy MCG-5-23-16. The broad-band (0.4-100keV) X-ray spectrum allows us to determine the nature of the high energy emission with little ambiguity. The X-ray continuum consists of a cutoff power-law of photon index Γ=1.9, absorbed through Compton-thin matter of …
Towards an understanding of the Of?p star HD 191612: optical spectroscopy
Walborn, Nolan R.; Donati, J. -F.; Herrero, A. +17 more
We present extensive optical spectroscopy of the early-type magnetic star HD 191612 (O6.5f?pe-O8fp). The Balmer and He I lines show strongly variable emission which is highly reproducible on a well-determined 538-d period. He II absorptions and metal lines (including many selective emission lines but excluding He IIλ4686 Å emission) are essentiall…
Coronal and Interplanetary Propagation of CME/Shocks from Radio, In Situ and White-Light Observations
Kaiser, M. L.; Bougeret, J. -L.; Reiner, M. J.
The kinematics of CMEs are well characterized to 32 Rsolar by height-time measurements from existing space-based and ground-based coronagraphs. Although there has been long-standing, but indirect, evidence that CMEs can exhibit significant deceleration as they propagate from Sun to Earth, the interplanetary kinematics of CMEs are not pr…
Acceleration Phase of Coronal Mass Ejections: I. Temporal and Spatial Scales
Veronig, Astrid M.; Temmer, Manuela; Vršnak, Bojan +3 more
We study kinematics of 22 coronal mass ejections (CMEs) whose motion was traced from the gradual pre-acceleration phase up to the post-acceleration stage. The peak accelerations in the studied sample range from 40, up to 7000 m s−2, and are inversely proportional to the acceleration phase duration and the height range involved. Accelera…
A systematic search for very massive galaxies at z > 4
McLure, R. J.; Dunlop, J. S.; Cirasuolo, M.
Motivated by the claimed discovery of a very massive galaxy (HUDF-JD2; M ~= 5 × 1011Msolar) at extreme redshift (z = 6.5) within the Hubble Ultra Deep Field (HUDF), we have completed a systematic search for comparably massive galaxies with z > 4 among the 2688 galaxies in our KS < 23.5 (AB) catalogue within t…