Search Publications
Equation of state of dark matter after Planck data
Xu, Lixin; Chang, Yadong
In this paper, we loosen the zero equation of state of dark matter to a constant wdm. By using the currently available cosmic observations, which include the type-Ia supernovae, the baryon acoustic oscillation, the WiggleZ measurements of matter power spectrum, and the cosmic microwave background radiation from the firs release of Planc…
Conjugate observations of quasi-periodic emissions by Cluster and DEMETER spacecraft
Pickett, J. S.; Parrot, M.; SantolíK, O. +3 more
<title type="main">Abstract<p label="1">Quasi-periodic (QP) emissions are electromagnetic emissions at frequencies of about 0.5-4 kHz that are characterized by a periodic time modulation of the wave intensity. Typical periods of this modulation are on the order of minutes. We present a case study of a large-scale long-lasting QP event …
Solar Surface and Atmospheric Dynamics. The Photosphere
Martínez Pillet, V.
Various aspects of the magnetism of the quiet sun are reviewed. The suggestion that a small scale dynamo acting at granular scales generates what we call the quiet sun fields is studied in some detail. Although dynamo action has been proved numerically, it is argued that current simulations are still far from achieving the complexity that might be…
Asymmetric Ejecta Distribution in SN 1006
Yamaguchi, Hiroya; Koyama, Katsuji; Uchida, Hiroyuki
We present the results from deep X-ray observations (~400 ks in total) of SN 1006 with Suzaku. The thermal spectrum from the entire supernova remnant (SNR) exhibits prominent emission lines of O, Ne, Mg, Si, S, Ar, Ca, and Fe. The observed abundance pattern in the ejecta components is in good agreement with that predicted by a standard model of Ty…
An Analysis of the Environments of FU Orionis Objects with Herschel
Henning, Thomas; Skinner, Stephen L.; Güdel, Manuel +13 more
We present Herschel-HIFI, SPIRE, and PACS 50-670 µm imaging and spectroscopy of six FU Orionis-type objects and candidates (FU Orionis, V1735 Cyg, V1515 Cyg, V1057 Cyg, V1331 Cyg, and HBC 722), ranging in outburst date from 1936 to 2010, from the "FOOSH" (FU Orionis Objects Surveyed with Herschel) program, as well as ancillary results from S…
One Moon, many measurements 2: Photometric corrections
Yokota, Y.; Mall, U.; Besse, S. +10 more
Observations of the lunar surface within the past 10 years have been made with various lunar remote sensing instruments, the Moon Mineralogy Mapper (M3) onboard the Chandrayaan-1 mission, the Spectral Profiler (SP), the Multiband Imager (MI), the Terrain Camera (TC) onboard the SELENE mission, and the ground based USGS Robotic Lunar Obs…
SWAP Observations of the Long-term, Large-scale Evolution of the Extreme-ultraviolet Solar Corona
Berghmans, David; Nicula, Bogdan; Seaton, Daniel B. +2 more
The Sun Watcher with Active Pixels and Image Processing (SWAP) EUV solar telescope on board the Project for On-Board Autonomy 2 spacecraft has been regularly observing the solar corona in a bandpass near 17.4 nm since 2010 February. With a field of view of 54 × 54 arcmin, SWAP provides the widest-field images of the EUV corona available from the p…
A Deep X-Ray View of the Hot Halo in the Edge-on Spiral Galaxy NGC 891
Bregman, Joel N.; Hodges-Kluck, Edmund J.
NGC 891 is a nearby edge-on galaxy that is similar to the Milky Way and has a hot X-ray-emitting halo that could arise from accretion, a galactic fountain, or a combination of the two. The metallicity of the gas can help distinguish between these models, and here we report on results that use 138 ks of archival Chandra data and 92 ks of new XMM-Ne…
Herschel-resolved Outer Belts of Two-belt Debris Disks around A-type Stars: HD 70313, HD 71722, HD 159492, and F-type: HD 104860
Bryden, G.; Stapelfeldt, K. R.; Werner, M. W. +1 more
We present dual-band Herschel/Photodetector Array Camera and Spectrometer imaging for four stars whose spectral energy distributions (SEDs) suggest two-ring disk architectures that mirror that of the asteroid-Kuiper Belt geometry of our own solar system. The Herschel observations at 100 µm spatially resolve the cold/outer-dust component for …
Filling the gap: a new class of old star cluster.
Usher, C.; Spitler, L. R.; Strader, J. +5 more
It is not understood whether long-lived star clusters possess a continuous range of sizes and masses (and hence densities) or if rather, they should be considered as distinct types with different origins. Utilizing the Hubble Space Telescope to measure sizes and long exposures on the Keck 10 m telescope to obtain distances, we have discovered the …