Search Publications
Correcting for background changes in CoRoT exoplanet data
Auvergne, M.; Costa, J. E. S.; Samadi, R. +4 more
Context: The CoRoT satellite is a highly accurate photometer with 2 channels respectively optimised for asteroseismology and exoplanet finding. The design includes an effective straylight rejection system, however residual straylight reaches the detectors.
Aims: We test four different background models in order to apply the best possible backg…
Comparison of High-Resolution TRACE Data to Spectroscopic CDS Data for Temperature Determination
Walsh, R. W.; Noglik, J. B.; Cirtain, J.
In this paper we aim to measure the temperature along a specific coronal loop feature which is located in an active region on the western solar limb. The data are taken from Joint Observing Program 146 and consist of high-cadence TRACE triple-filter images coinciding with sparse raster Coronal Diagnostic Spectrometer (CDS) spectroscopic data. The …
HST NICMOS Observations of Fast Infrared Flickering in the Microquasar GRS 1915+105
Patel, Shannon G.; Remillard, Ronald; Pooley, Guy G. +3 more
We report infrared observations of the microquasar GRS 1915+105 using the NICMOS instrument of the Hubble Space Telescope during nine visits in 2003 April-June. During epochs of high X-ray/radio activity near the beginning and end of this period, we find that the 1.87 µm infrared flux is generally low (~2 mJy) and relatively steady. However,…
Hydrodynamical and radiative transfer modeling of meteoroid impacts into Saturn's rings
Sugita, Seiji; Cuzzi, Jeffrey N.; Asphaug, Erik +2 more
In a small hypervelocity impact, superheated gas and particles glow brightly with thermal emission for a brief time interval at short wavelengths; this phenomenon is referred to as an impact flash. Over the past decade, impact flashes have been observed on the Moon and in the laboratory in both the IR and visible portions of the spectrum. These ph…
The Spitzer View of Low-Metallicity Star Formation. II. Mrk 996, a Blue Compact Dwarf Galaxy with an Extremely Dense Nucleus
Hunt, Leslie K.; Thuan, Trinh X.; Izotov, Yuri I.
We present new Spitzer, UKIRT, and MMT observations of the blue compact dwarf galaxy (BCD) Mrk 996, with an oxygen abundance of 12 + log (O/H) = 8.0. This galaxy possesses an extraordinarily dense nuclear star-forming region, with a central density of ~106 cm-3, a very red color J - K = 1.8, broad- and narrow-line components,…
The early-type semidetached binary system V716 Centaurus
Demircan, O.; Bakış, V.; Eker, Z. +1 more
New high-resolution spectra of V716 Cen revealed for the first time lines of the secondary component and its radial velocities. The simultaneous solution of the new radial velocity curves and the Hipparcos light curve yield the reliable absolute dimensions of this semidetached system. The masses for the primary and secondary are M1 = 5.…
An effort to derive an empirically based, inner-magnetospheric electric field model: Merging Cluster EDI and EFW data
Khotyaintsev, Y.; Matsui, H.; Jordanova, V. K. +2 more
A key ingredient for modelling many inner-magnetospheric processes is the realistic representation of the spatio-temporal dynamics of the inner-magnetospheric electric field, or, IMEF. The Cluster Mission provides a unique opportunity to construct an IMEF model using electric field measurements from both the electron drift instrument (EDI) and the…
Transport of transient solar wind particles in Earth's cusps
Dandouras, I.; Rème, H.; Parks, G. K. +7 more
An important problem in space physics still not understood well is how the solar wind enters the Earth's magnetosphere. Evidence is presented that transient solar wind particles produced by solar disturbances can appear in the Earth's mid-altitude (~5 RE geocentric) cusps with densities nearly equal to those in the magnetosheath. That t…
Variations in the chorus source location deduced from fluctuations of the ambient magnetic field: Comparison of Cluster data and the backward wave oscillator model
Gurnett, D. A.; Pickett, J. S.; Trakhtengerts, V. Y. +5 more
We study the motion of the source region of magnetospheric chorus emissions using multipoint measurements of VLF wave emissions and geomagnetic field onboard the Cluster spacecraft. The geomagnetic field data are matched to a parameterized model of the local magnetic field, and the spatiotemporal dynamics of the magnetic field are obtained on this…
Radiation Effects on Stressed Ge:Ga Array Detector of Far-Infrared Surveyor on AKARI
Nakagawa, Takao; Shirahata, Mai; Doi, Yasuo +6 more
AKARI, the Japanese infrared astronomical satellite, was launched on 2006 February 21 (UT) and put into a sun-synchronous polar orbit at an altitude of 700 km. Cosmic radiations, particularly protons in the South Atlantic Anomaly (SAA), were expected to affect the performance of the stressed Ge:Ga array far-infrared detector on board AKARI. One of…