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X-ray observations of the Crab Pulsar and Nebula with JEM-X on INTEGRAL
Walter, R.; Schmidt, M.; Westergaard, N. J. +8 more
The Crab pulsar is the best studied rotation powered pulsar. We report the results obtained in the 3-35 keV energy band with the X-ray monitor, JEM-X, on ESAs recently launched gamma -ray mission, INTEGRAL.
Based on observations with INTEGRAL, an ESA project with instruments and science data centre funded by ESA member states (especially the …Nuclear Starburst Activity in the Seyfert 2 Galaxy NGC 2273
Gu, Qiu-Sheng; Lei, Shi-Jun; Shi, Lei +2 more
We present spectrophotometric results of the Seyfert 2 galaxy NGC 2273. The presence of high-order Balmer absorption lines (H8, H9, H10) and weak equivalent widths of CaII K λ3933, CN λ4200, G-band λ4300 and MgIb λ5173 clearly indicate recent star-forming activity in the nuclear region. Using a simple stellar population synthesis model, we find th…
Deriving effective sunspot temperatures from SOHO/VIRGO irradiance measurements. A starspot modelling approach
Hanslmeier, A.; Eker, Z.; Otruba, W. +2 more
A method is developed to obtain mean effective sunspot temperatures from satellite irradiance deficits. Using a formalism derived from a star spot modelling approach, this method only requires accurate positions and areas of sunspots - but not intensities. The method is applied to SOHO/VIRGO spectral solar irradiance (SSI) at 402, 500, and 862 nm …
Identification of low frequency waves in the vicinity of the terrestrial bow shock
Walker, S. N.; Andre, M.; Balikhin, M. A. +1 more
In this paper, methods for the determination of the wave mode for low frequency waves based on observed differences in phase are reviewed. Examples, using measurements made in the terrestrial foreshock and magnetosheath, are used to illustrate the application of these methods. The use of advance methods such as NARMAX modelling or genetic algorith…
Outbursts in the Be star HR 2501
Carrier, F.; Burki, G.
The Be star
Quiet time MEV electron increases at solar maximum: Ulysses cospin/ket observations
Fichtner, H.; Kunow, H.; Wibberenz, G. +10 more
The Ulysses trajectory provides a unique opportunity to study the propagation of MeV electrons in a wide range of heliographic latitudes and during varying conditions in the inner heliosphere. In recent papers we reported Ulysses Kiel Electron Telescope (KET) observations from the Ulysses launch up to the end of the second fast latitude scan in la…
Optical design of the Optical Monitoring Camera (OMC) of INTEGRAL
Mas-Hesse, J. M.; Renotte, E.; Rochus, P. +5 more
The Optical Monitoring Camera (OMC) will observe the optical emission from the main targets of the gamma-ray instruments onboard the ESA mission INTEGRAL. The OMC is based on a refractive optics with an aperture of 50 mm focused onto a large format CCD (1024 x 2048 pixels), and a field of view of 5degrx5 degr . This paper describes the design of t…
Systematic effects induced on IBIS detectors by background and inhomogeneity of the spatial response
Bird, A. J.; Ubertini, P.; Bazzano, A. +4 more
The spatial distribution of the background events may affect the source detection capability of IBIS at high energies (>=200 keV) for both ISGRI and PICsIT layers. The observed background is found to be variable and spatially structured, and in some cases its properties strongly deviate from the expected statistical behaviour. Background correc…
Continuous tracking of CMEs using MICA, and LASCO C2 and C3 coronagraphs
Schwenn, R.; Stenborg, G.; Balmaceda, L. +3 more
In this work we have tracked coronal mass ejections observed with the ground based Mirror Coronagraph for Argentina (MICA) and the Large Angle and Spectroscopic Coronagraph (LASCO) C2 and C3 on board of the Solar and Heliospheric Observatory (SOHO). The MICA telescope is located at El Leoncito (31.8 S, 69.3 W), San Juan (Argentina), since 1997 as …
Structure of a simple sunspot from the inversion of IR spectral data
Krupp, N.; Woch, J.; Solanki, S. K. +5 more
Analysis of spectral data of two neighboring infrared lines, Fe i 15648.5 Å (g = 3) and Fe i 15652.9 Å (g_eff = 1.53) are carried out for a simple sunspot when it was near the solar disk center (mu = 0.92), to understand the basic structure of sunspot magnetic field. Inversions of Stokes profiles are carried out to derive different atmospheric par…