Search Publications
X-Ray Observations of the Sagittarius D HII Region toward the Galactic Center with Suzaku
Tsujimoto, Masahiro; Koyama, Katsuji; Tsuru, Takeshi Go +3 more
We present a Suzaku X-ray study of the Sagittarius D (Sgr D) HII region in the Galactic center region. Two 18' × 18' images by the X-ray Imaging Spectrometer (XIS) encompass the entire Sgr D complex. Thanks to the low background, XIS discovered two diffuse sources with low surface brightness and obtained their high signal-to-noise ratio spectra. O…
The molecular environment of the massive star forming region NGC 2024: Multi CO transition analysis
Emprechtinger, M.; Stutzki, J.; Güsten, R. +10 more
Context: Sites of massive star formation have complex internal structures. Local heating by young stars and kinematic processes, such as outflows and stellar winds, generate large temperature and velocity gradients. Complex cloud structures lead to intricate emission line shapes. CO lines from high mass star forming regions are rarely Gaussian and…
Relating basic properties of bright early-type dwarf galaxies to their location in Abell 901/902
Heymans, C.; Gray, M. E.; Wolf, C. +21 more
We present a study of the population of bright early-type dwarf galaxies in the multiple-cluster system Abell 901/902. We use data from the STAGES survey and COMBO-17 to investigate the relation between the color and structural properties of the dwarfs and their location in the cluster. The definition of the dwarf sample is based on the central su…
The young active star SAO 51891 (V383 Lacertae)
Frasca, A.; Biazzo, K.; Covino, E. +5 more
Aims: The aim of this work is to investigate the surface inhomogeneities of a young, late-type star, SAO 51891, at different atmospheric levels, from the photosphere to the upper chromosphere, analyzing contemporaneous optical high-resolution spectra and broad-band photometry.
Methods: The full spectral range of FOCES@CAHA (R ≃ 40 000) is used…
Doppler-Broadened Iron X-Ray Lines From Tycho's Supernova Remnant
Petre, Robert; Kunieda, Hideyo; Makishima, Kazuo +13 more
We use Suzaku observations to measure the spatial variation of the Fe Kα line with radius in the Tycho supernova remnant. The Fe line widths show a significant decrease from a FWHM value of 210 eV at the center to 130 eV at the rim. Over the same radial range the line center energy remains nearly constant. These observations are consistent with a …
Spectral energy distributions of type 2 quasi-stellar objects: obscured star formation at high redshifts
Rigopoulou, D.; Hasinger, G.; Mainieri, V. +6 more
We present new mid-infrared and submillimetre observations for a sample of eight high-redshift type 2 quasi-stellar objects (QSOs) located in the Chandra Deep Field-South. The sources are X-ray absorbed with luminosities in excess of 1044 ergs-1. Two of the targets have robust detections, S/N > 4, while further three targe…
Water ice clouds in the Martian atmosphere: Two Martian years of SPICAM nadir UV measurements
Fussen, D.; Mateshvili, N.; Vanhellemont, F. +4 more
The SPICAM instrument onboard Mars Express has successfully performed two Martian years (MY 27 and MY28) of observations. Water ice cloud optical depths spatial and temporal distribution was retrieved from nadir measurements in the wavelength range 300-320 nm. During the northern spring the cloud hazes complex distribution was monitored. The cloud…
Simulation of a flux emergence event and comparison with observations by Hinode
Solanki, S. K.; Lagg, A.; Cheung, M. C. M. +2 more
Aims: We study the observational signature of flux emergence in the photosphere using synthetic data from a 3D MHD simulation of the emergence of a twisted flux tube.
Methods: Several stages in the emergence process are considered. At every stage we compute synthetic Stokes spectra of the two iron lines Fe I 6301.5 Å and Fe I 6302.5 Å and degr…
GEOPHYSICS, ASTRONOMY, AND ASTROPHYSICS: ULF Waves Associated with Solar Wind Deceleration in the Earth's Foreshock
Dandouras, I.; Lucek, E.; Rème, H. +3 more
Characteristics of ULF waves associated with the solar wind deceleration in the Earth's foreshock on 6-7 April 2003 is studied using the wave telescope technique. In the satellite frame, the ULF waves are the left-handed polarized and quasi anti-parallel propagating mode, with a power peak at about 18.63 mHz. The wave vector in the GSE coordinates…
An Ultraviolet Search for Interstellar CS
Snow, Theodore P.; Destree, Joshua D.; Black, John H.
High- and medium-resolution ultraviolet spectra from the Space Telescope Imaging Spectrograph (STIS) and the Goddard High Resolution Spectrograph (GHRS) were used to study the diatomic molecule CS through the C-X(0,0) band at 1401 Å. The band was modeled to verify profile shape. The rest wavelength of the C-X band is refined to a value of 1400.88 …