Search Publications
Beam test of a prototype phoswich detector assembly for the PoGOLite astronomical soft gamma-ray polarimeter
Fukazawa, Y.; Kamae, T.; Kanai, Y. +27 more
We report about the beam test on a prototype of the balloon-based astronomical soft gamma-ray polarimeter, PoGOLite (Polarized Gamma-ray Observer Light Version) conducted at KEK Photon Factory, a synchrotron radiation facility in Japan. The synchrotron beam was set at 30, 50, and 70 keV and its polarization was monitored by a calibrated polarimete…
Venus atmosphere dynamics: A continuing enigma
Bougher, S. W.; Del Genio, A. D.; Limaye, S. S. +5 more
The dynamics of the Venus atmosphere presents a major unsolved problem in planetary science: the so-called superrotation of the lower atmosphere and its transition to a subsolar-to-antisolar circulation in the upper atmosphere. (In this paper we place the dividing line between the lower and upper atmosphere at 90-100 km altitude (pressure 0.39 to …
Absorption in Burst Emission
Rucker, H. O.; Kaiser, M. L.; Lecacheux, A. +5 more
Here we report a radio burst in absorption at 9 - 30 MHz observed with the UTR-2 telescope. This event occurred on 19 August 2003 about 11:16 - 11:26 UT, against solar type IV/II emission background. It is the first event where absorption was observed below 30 MHz. The absorption region, comparable with the solar radius size, traveled a long dista…
Ultraviolet spectrum of FU Ori and a ``Compromise'' model of the FUor
Errico, L.; Lamzin, S. A.; Kravtsova, A. S. +1 more
We have analyzed the Hubble Space Telescope spectrum of the young star FU Ori in the range 2300 3100 Å. The long-wavelength part of the spectrum is similar to the spectrum of a supergiant with T eff ≃ 5000 6000 K, but the range of wavelengths shorter than ≃2600 Å is dominated by radiation from a region with T eff ≃ 9000 K. We…
Ionized and neutral gas in the peculiar star/cluster complex in NGC 6946
Larsen, S.; Bastian, N.; Afanasiev, V. L. +8 more
The characteristics of ionized and H I gas in the peculiar star/cluster complex in NGC 6946, obtained with the 6-m telescope (BTA) Special Astrophysical Observatory Russian Academy of Sciences (RAS), the Gemini North telescope, and the Westerbork Synthesis Radio Telescope, are presented. The complex is unusual as hosting a super star cluster, the …
Spectral Analysis of the Pre-WN Candidate HD 326823
Marcolino, W. L. F.; de Araújo, F. X.; Lorenz-Martins, S. +1 more
We present a spectral analysis of the peculiar emission-line star HD 326823. As has been reported in the literature, this object seems to be a rare, massive star entering the Wolf-Rayet (W-R) phase. In order to confirm its evolutionary status, we used the radiative transfer code CMFGEN to obtain its physical parameters and chemical abundances for …
Non-circular motion evidence in the circumnuclear region of M100 (NGC 4321)
Battaner, E.; Mediavilla, E.; Castillo-Morales, A. +1 more
We analyse new integral-field spectroscopy of the inner region (central 2.5 kpc) of the spiral galaxy NGC 4321 to study the peculiar kinematics of this region. Fourier analysis of the velocity residuals obtained by subtracting an axisymmetric rotation model from the Hα velocity field indicates that the distortions are global features generated by …
Spatial Characterization of a Flare Using Radio Observations and Magnetic Field Topology
Mandrini, C. H.; Cristiani, G.; Rovira, M. G. +4 more
Using magnetograms, EUV and Hα images, Owens Valley Solar Array microwave observations, and 212-GHz flux density derived from the Solar Submillimeter Telescope data, we determine the spatial characteristics of the 1B/M6.9 flare that occurred on November 28, 2001, starting at 16:26 UT in active region (AR) NOAA 9715. This flare is associated with a…
Stellar Populations Found in the Central Kiloparsec of Four Luminous Compact Blue Galaxies at Intermediate z
Hoyos, C.; Koo, D. C.; Guzmán, R. +2 more
We investigate the star formation history of the central regions of four luminous compact blue galaxies (LCBGs) at intermediate redshift using evolutionary population synthesis techniques. LCBGs are blue (B - V <= 0.6), compact (µB <= 21.0 mag arcsec-2) galaxies with absolute magnitudes MB brighter than…
Abundances in planetary nebulae: Hb 5
Pottasch, S. R.; Surendiranath, R.
The ISO spectra of the bilobal planetary nebula