Search Publications
Broadband X-ray spectrum of intermediate polar V1223 Sgr
Sunyaev, R.; Revnivtsev, M.; Lutovinov, A. +2 more
We present the broadband phase averaged spectrum of one of the brightest intermediate polars V1223 Sgr, obtained with INTEGRAL and RXTE observatories (3-100 keV). Good statistical quality of the spectrum in a hard X-ray energy band (INTEGRAL/IBIS and RXTE/HEXTE) allowed us to disentangle contributions of a direct optically thin plasma emission and…
Modeling of remote sensing of thin current sheet
Parks, G. K.; Lee, E.; Wilber, M. +2 more
Cluster encountered a thin current sheet in the magnetotail during a substorm on Oct. 1, 2001. The phase space distributions observed by Cluster CIS showed large gradients in the phase space with ions existing only in one hemisphere of the phase space. It has been suggested that these non-gyrotropic distributions come from remote sensing of a thin…
Virgo High-Resolution CO Survey: IV. Spiral-Driven Gas Dynamics in the Non-Barred Seyfert Galaxy NGC 4501
Kohno, Kotaro; Koda, Jin; Onodera, Sachiko +1 more
We report on high-resolution interferometer observations of the 12CO(J = 1-0) emission in the central 5kpc region of the Seyfert 2 galaxy NGC 4501. The observations were made using the Nobeyama Millimeter Array during a long-term CO line survey of Virgo spirals. The major features are: (1) a nuclear concentration with a radius of r ∼ 5'…
High resolution solar magnetometry with the spectrograph of the Pic du Midi Turret Dome
Roudier, Th.; Muller, R.; Mein, P. +2 more
We present the first results obtained with a new Ferroelectric Liquid Crystal (FLC) polarimeter operating with the spectrograph of the Pic du Midi Turret Dome, since September 2003. We observed the solar granulation around active region NOAA 0459 with the Multichannel Subtractive Double Pass (MSDP) operating mode and analysed the circular polariza…
A Substellar Companion to van Maanen 2
Makarov, Valeri V.
The Hipparcos data for the nearest white dwarf van Maanen 2 (=HIP 3829; distance of 4.4 pc) indicate astrometric binarity, in that the proper motion has a large first derivative not accounted for as a perspective acceleration due to changing distance. The presence of a companion was suspected, but never demonstrated, from the pre-Hipparcos astrome…
New insight into the blinker phenomenon and the dynamics of the solar transition region
Doyle, J. G.; Madjarska, M. S.; Roussev, I. I.
We present, for the first time, blinker phenomena being associated with brightenings in pre-existing coronal loops registered by the Extreme-ultraviolet Imaging Telescope (EIT) in Fe XII 195 Å. The brightenings occur during the emergence of new magnetic flux as registered by the Big Bear Solar Observatory (BBSO) magnetograph. The blinkers were ide…
X-Ray Line-emitting Objects in XMM-Newton Observations: The Tip of the Iceberg
Braito, V.; Caccianiga, A.; Severgnini, P. +2 more
We present preliminary results from a novel search for X-ray line-emitting objects (XLEOs) in XMM-Newton images. Three sources have been detected in a test-run analysis of 13 XMM-Newton observations. The three objects found are most likely extremely absorbed active galactic nuclei characterized by a column density NH~1024 cm<…
Dwarf Novae with Newly Determined Parallaxes: Model Analyses of VY Aquarii, RU Pegasi, and T Leonis
Sion, E. M.; Hamilton, R. T.
Using newly determined parallaxes for dwarf novae, we have derived outburst accretion rates for VY Aqr, RU Peg, and T Leo, and for T Leo during quiescence. The two short-period dwarf novae, VY Aqr and T Leo, show good agreement with optically thick steady-state accretion disks in outburst, whereas RU Peg shows a significant departure from a steady…
Spitzer Space Telescope View of Diffuse Near-Infrared Continuum Emission in the Galaxy
Lu, Nanyao
The Infrared Array Camera (IRAC) multiband images from the Spitzer Space Telescope First Look Survey of two 1deg×5' areas of diffuse interstellar medium (ISM) are used to study the near-infrared (NIR; 2-5 µm) continuum emission and its relation to the mid-infrared (6-10 µm) aromatic features in emission (AFEs). We…
Spitzer Space Telescope Observations of the Aftermath of Microlensing Event MACHO-LMC-5
Stern, Daniel; Kallivayalil, Nitya; Nguyen, Hien T. +3 more
We have carried out photometry of the microlensing event MACHO-LMC-5 with Spitzer Infrared Array Camera (IRAC) 10 years after the magnification of the LMC source star was recorded. This event is unique in the annals of gravitational microlensing: the lensing star itself has been observed using the Hubble Space Telescope (once with WFPC2 and twice …