Search Publications
Dark side of the Universe after Planck data
Cheng, Cheng; Huang, Qing-Guo
Recently released Planck data imply a smaller Hubble constant H0 than that from the Hubble Space Telescope project (HST) and a larger percentage of the matter components Ωm compared to the Supernova Legacy Survey (SNLS) in the Λ cold dark matter (CDM) model. In this paper we found that even though the tension on H0…
Hot magnetospheric O+ and cold ion behavior in magnetopause reconnection: Cluster observations
Liu, Y.; Kistler, L. M.; Mouikis, C. G. +2 more
In reconnection, the presence of heavy ions like O+ increases the ion mass density reducing the fluid's Alfvén speed. In addition, it may modify the reconnection structure, which can also change the reconnection rate. However, because O+ ions have a larger Larmor radii than H+ ions at the same velocity, they may no…
Timescales of fluvial activity and intermittency in Milna Crater, Mars
Head, James W.; Fassett, Caleb I.; Buhler, Peter B. +1 more
Milna Crater, Mars (23.4S, 12.3W) exhibits signs of fluvial modification early in Mars history, including a large multi-lobed fan deposit cut by several sinuous valleys. We describe the past hydrologic conditions in Milna and the surrounding area, including a potential lake with a volume of 50 km3. We also introduce new methods (i) to c…
Cross-correlation of cosmic far-infrared background anisotropies with large scale structures
Doré, O.; Lagache, G.; Serra, P. +2 more
We measure the cross-power spectra between luminous red galaxies (LRGs) from the Sloan Digital Sky Survey (SDSS)-III data release 8 (DR8) and cosmic infrared background (CIB) anisotropies from Planck and data from the Improved Reprocessing (IRIS) of the Infrared Astronomical Satellite (IRAS) at 353, 545, 857, and 3000 GHz, corresponding to 850, 55…
Characteristics of the flank magnetopause: Cluster observations
Tenfjord, P.; Haaland, S.; Maggiolo, R. +6 more
The magnetopause is a current sheet forming the boundary between the geomagnetic field on one side and the shocked solar wind on the other side. This paper discusses properties of the low-latitude dawn and dusk flanks of the magnetopause. The reported results are based on a large number of measurements obtained by the Cluster satellites during mag…
A Comparison of Reconstruction Methods for the Estimation of Coronal Mass Ejections Kinematics Based on SECCHI/HI Observations
Srivastava, Nandita; Mishra, Wageesh; Davies, Jackie A.
A study of the kinematics and arrival times of coronal mass ejections (CMEs) at Earth, derived from time-elongation maps (J-maps) constructed from STEREO/heliospheric imager (HI) observations, provides an opportunity to understand the heliospheric evolution of CMEs in general. We implement various reconstruction techniques, based on the use of tim…
Delving Into X-ray Obscuration of Type 2 AGN, Near and Far
Heckman, Timothy M.; Gandhi, Poshak; Yaqoob, Tahir +4 more
Using self-consistent, physically motivated models, we investigate the X-ray obscuration in 19 Type 2 [O III] 5007 Å selected active galactic nuclei (AGNs), 9 of which are local Seyfert 2 galaxies and 10 of which are Type 2 quasar candidates. We derive reliable line-of-sight and global column densities for these objects, which is the first time th…
A radar map of Titan Seas: Tidal dissipation and ocean mixing through the throat of Kraken
Soderblom, Jason M.; Kirk, Randolph L.; Lorenz, Ralph D. +9 more
We present a radar map of the Titan’s seas, with bathymetry estimated as proportional to distance from the nearest shore. This naïve analytic bathymetry, scaled to a recent radar sounding of Ligeia Mare, suggests a total liquid volume of ∼32,000 km3, at the low end of estimates made in 2008 when mapping coverage was incomplete. We note …
Can eccentric debris disks be long-lived?. A first numerical investigation and application to ζ2 Reticuli
Eiroa, C.; Marshall, J. P.; Montesinos, B. +13 more
Context. Imaging of debris disks has found evidence for both eccentric and offset disks. One hypothesis is that they provide evidence for massive perturbers, for example, planets or binary companions, which sculpt the observed structures. One such disk was recently observed in the far-IR by the Herschel Space Observatory around ζ2 Retic…
A Chandra look at the X-ray faint millisecond pulsars in the globular cluster NGC 6752
Heinke, C. O.; Cohn, H. N.; Lugger, P. M. +5 more
We combine new and archival Chandra observations of the globular cluster NGC 6752 to create a deeper X-ray source list, and study the faint radio millisecond pulsars (MSPs) of this cluster. We detect four of the five MSPs in NGC 6752, and present evidence for emission from the fifth. The X-rays from these MSPs are consistent with thermal emission …