Search Publications
XMM-Newton Observation of the Northeastern Limb of the Cygnus Loop
Tsunemi, Hiroshi; Miyata, Emi; Nemes, Norbert
In this paper we performed moderate-resolution spectroscopy on the data obtained with XMM-Newton of the northeastern limb of the Cygnus Loop. This observation was proposed as a higher resolution follow-up to that made by ASCA. We investigated the radial variation of the temperature, ionization timescale, elemental abundances, and hydrogen column d…
Inaccuracies in the spectral classification of stars from the Tycho-2 Spectral Type Catalogue
Tsvetkov, A. S.; Popov, A. V.; Smirnov, A. A.
We compare the spectroscopic and trigonometric parallaxes of common stars from the Tycho-2 Spectral Type and Hipparcos Catalogues. This comparison has revealed that the distance estimations for the overwhelming majority of stars by both methods yield very similar results. However, there is a small fraction of stars for which the distance estimates…
Studies of Zonal Flows Driven by Drift Mode Turbulence in Laboratory and Space Plasmas
Davies, J. A.; Vaivads, A.; Dunlop, M. W. +8 more
The interaction between broadband drift mode turbulence and zonal flows is an important topic associated with transport at plasma boundaries. The generation of zonal flows by the modulational instability of broad band drift waves has resulted in the observation of self organized solitary wave structures at the magnetopause. To understand these str…
XMM-Newton Observation of the Cluster Zw 1305.4+2941 in the Field SA 57
Gastaldello, Fabio; Fusco-Femiano, Roberto; Vagnetti, Fausto +1 more
We report the details of an XMM-Newton observation of the cluster of galaxies Zw 1305.4+2941 at the intermediate redshift z = 0.241, increasing the small number of interesting X-ray constraints on properties of ~3 keV systems above z = 0.1. Based on the ~45 ks XMM-Newton observation, we find that within a radius of 228 kpc the cluster has an unabs…
On the peculiar properties of the narrow-line quasar PG 1543+489
Bianchi, Stefano; Piconcelli, Enrico; Vignali, Cristian +1 more
We present the analysis of four XMM-Newton observations of the narrow-line quasar PG 1543+489 at z = 0.400 carried out over a rest-frame time-scale of about 3 yr. The X-ray spectrum is characterized by a broad, relativistic iron Kα emission line and a steep photon index, which can be both explained by a ionized reflection model, where the source o…
Impact of Active Regions on Coronal Hole Outflows
Habbal, Shadia Rifai; McIntosh, Scott W.; Scholl, Isabelle F.
Establishing the sources of the fast and slow solar wind is important for understanding their drivers and their subsequent interaction in interplanetary space. Although coronal holes continue to be viewed as the main source of the fast solar wind, there is recent evidence that the quiet Sun provides other spatially concentrated sources. To identif…
Number Density Evolution of Ks-Band-Selected High-Redshift Galaxy Populations in the AKARI North Ecliptic Pole Field
Oyabu, Shinki; Matsuhara, Hideo; Takagi, Toshinobu +5 more
We present the number counts of Ks-band-selected high-redshift galaxy populations such as extremely red objects (EROs), B-, z-, and K-band-selected galaxies (BzKs) and distant red galaxies (DRGs) in the AKARI NEP field. These high-redshift galaxy samples are extracted from a multicolor catalog combining optical data from Suprime-Cam on …
Suzaku Observations of the Cluster of Galaxies Abell 2052
Kunieda, Hideyo; Ohashi, Takaya; Mitsuda, Kazuhisa +7 more
The results from Suzaku X-ray Imaging Spectrometer (XIS) observations of relaxed cluster of galaxies, Abell 2052, are presented. Offset pointing data were used to estimate the Galactic foreground emission in the direction of the cluster. Significant soft X-ray excess emission above this foreground, the intracluster medium emission, and other backg…
Young globular clusters in an old S0: clues to the formation history of NGC 4570
Anders, P.; Kotulla, R.; Fritze, U.
We here present our first attempt to use globular clusters as tracers of their parent galaxy's formation history. Globular cluster systems of most early-type galaxies feature two peaks in their optical colour distributions. Blue-peak globular clusters are generally believed to be old and metal-poor. The ages, metallicities, and the origin of the r…
The MESSENGER mission to Mercury: Status after the Venus flybys
Solomon, Sean C.; McNutt, Ralph L., Jr.; Grant, David G. +2 more
NASA's MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, launched on 3 August 2004, is well into its voyage to initiate a new era in our understanding of the terrestrial planets. The mission, spacecraft, and payload are designed to answer six fundamental questions regarding the innermost planet during three flyb…