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1.
A new type of descent vehicle (DVs) is described: a descent vehicle with an inflatable braking device (IBD DV). IBD development issues, as well as materials needed for the design, manufacturing, and testing of an IBD and its thermal protection, are discussed. A list is given of Russian integrated test facilities intended for testing IBD DVs. Progress is described in the development of IBD DVs in Russia and abroad.  相似文献   

2.
The experiment on gamma-ray spectrometry planned to be fulfilled onboard the Phobos-Grunt spacecraft is described. The principles of the experiment and the application of gamma-spectrometry to the space investigations are considered. The design and operation of the instrument are described.  相似文献   

3.
A multiplexX-ray image analyser is described. It consists in a time-modulated coded aperture associated with a solid state detector. The system combines the high efficiency and good spectral resolution of solid state spectrometers with the spatial resolution of the coded aperture (200 ).The device can be installed at the focus of a grazing incidence telescope to make images and spectra of faint astronomicalX-ray sources.  相似文献   

4.
Electrostatic dust-cyclotron (EDC) waves can be excited in a collisional, magnetized, dusty plasma by passing a current along the magnetic field, B, permeating the plasma. The minimum B field-aligned electric field required for excitation of the EDC waves is typically several times smaller than the one required for excitation of dust-acoustic (DA) waves.Two dusty plasmas are considered in more detail, namely (a) a comet tail plasma, and (b) one which may be produced in a laboratory device of the type described by Xu et al. (1992).  相似文献   

5.
The mechanical and electronic device of the microphotometer is described. The on-line data compression is performed in the domain of the HAAR transform of the measurement points. This method provides a fast treatment of the measurement data in the computer and changes the large data material sampled in equidistant steps whose width can be chosen by the seeing condition into a non-equidistant grid whose widths depend only on the characteristic length of the signal. The grain noise is eliminated. An automatical discrimination between stars and galaxies is possible. The accuracy of the photometry was tested by comparing with the photoelectrically determined B-brightness distribution of M 81.  相似文献   

6.
We present the results of the simultaneous XMM‐Newton and Chandra observations of the bright Seyfert 1.9 galaxy MCG–5‐23‐16, which is one of the best known examples of a relativistically broadened iron Kα line. We find that: a) the soft X‐ray emission is likely to be dominated by photoionized gas, b) the complex iron emission line is best modelled with a narrow and a broad component with a FWHM ∼44000 km/s. This latter component has an EW ∼50 eV and its profile is well described with an emission line mainly originating from the accretion disk a few tens of gravitational radii from the central black hole and viewed with an inclination angle ∼40°. We found evidence of a possible sporadic absorption line at ∼7.7 keV which, if associated with Fe XXVI Kα resonance absorption, is indicative of a possible high velocity (v ∼ 0.1c) outflow. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

7.
The STEP-F satellite telescope for measuring electrons and protons of the Photon scientific equipment is described. Its design features are given. The device detects electrons, protons, and α-particles in the energy range 0.18–2.3, 7.4–55.2, and 298–160.0 MeV, respectively. Geometric factors vary in the range of 12.4–21.7 cm2 sr, depending on the energy of the particles. In addition, there are three channels of mixed recording of particles of different types and channels of recording of the secondary electromagnetic radiation generated in the construction materials of the device and spacecraft. Methods and results of the computer simulation of the passage of the particle through detector materials are presented, along with configuration, calibration measurements, and tests (both standalone and integrated) within the complex of scientific instrumentation and spacecraft. Updated data on geometric factors of the device and energy ranges of the direct detection of charged high-energy particles and of channels of mixed recording of several types of particles are given. Special software is described for the rapid analysis of the processed data of the STEP-F telescope, and the visualization of time variations of particle fluxes with different time resolution in some periods of high solar activity and in its absence.  相似文献   

8.
The authors, collaborating during the winter 1966/67, performed numerical investigations on form and character of periodic solutions of the restricted problem of three bodies in the Sun–Jupiter-System and in the neighbourhood of the resonances of the (k + 1)/k type. The principal part of these computations which were achieved using a fast IBM-computer refers to the cases 2/1 (Hecuba-gap) and 3/2 (Hilda-group). The results gave new insight into the genealogy of periodic orbits in the regions which do not contain solutions of Poincaré's first genre. Moreover, L. Carpenter tried to develop an analytical theory (here not explicitely described) which leads to convergent trigonometric series for the coordinates of periodic orbits with restricted eccentricities, using the method of general perturbations in rectangular coordinates recently published by P. Musen and himself.  相似文献   

9.
The momentum loss for a possible antimatter meteor entrance can be described by the combination of two terms. One which can be characterized by the mechanism of annihilation and a second one, the well known mechanism, which is common for all koinomatter (ordinary) meteors. That is, the momentum loss caused by the air molecules swept up by the moving object. We discuss, in this paper, the contribution of the rocket effect caused by the action of the secondaries which can be produced by the annihilation interactions of the antiatoms with the air molecules. The momentum loss of an iron type meteor made of antimatter, as a function of its equivalent radius R, can be described by the formula, J (MeV/c) = 8R (cm), for values of R within the range 1 cm < R < 5 cm and can be resulted by a single annihilation interaction of a nucleon-antinucleon pair.  相似文献   

10.
11.
Hathaway  David H. 《Solar physics》1988,117(2):329-341
A method is described for constructing artificial data that realistically simulate photospheric velocity fields. The velocity fields include rotation, differential rotation, meridional circulation, giant cell convection, supergranulation, convective limb shift, p-mode oscillations, and observer motion. Data constructed by this method can be used for testing algorithms designed to extract and analyze these velocity fields in real Doppler velocity data.  相似文献   

12.
A technique for finding the oscillation spectrum of a rotating star based on the solution of two simultaneous ordinary differential equations is described. Results are presented for someg-modes of the polytrope of index 2. It appears that the functional dependence of frequency on rotational velocity is different for different azimuthal wave numbersm.  相似文献   

13.
An overview of the three major types of impurity band conduction (IBC) detectors — Blocked Impurity Band (BIB) detector, Solid State Photomultiplier (SSPM) and Visible Light Photon Counter (VLPC) - pioneered by Rockwell is presented. Key functional features, level of developmental maturity and applications to astronomy are described.  相似文献   

14.
The optical layout and performance characteristics of a device for measuring the four Stokes parameters are reported, and the principle of its operation is described. The device is designed for use in the NES echelle spectrograph mounted in the Nasmyth-2 focus of the 6-meter telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. Tests of the device operating on the telescope showed the gain in throughput to be a factor of 2.7 and 6 in the red (5000–7000 Å Å) and blue (3500–4700 Å Å) parts of the spectrum, respectively, compared to an analyzer based on Fresnel rhombi.  相似文献   

15.
A new method for reddening determination in the uvby system is described. Using a Quby parameter calibrated in terms of b–y it is possible to determine simultaneously luminosity, spectral type, reddening, and metallicity of a star. The colour excess rations for the uvby photometric system are given and also analytical functions for the ZAMS are presented.  相似文献   

16.
The Coudé feed of the vacuum telescope (aperture D = 65 cm) at the Big Bear Solar Observatory (BBSO) is currently completely remodelled to accommodate a correlation tracker and a high‐order Adaptive Optics (AO) system. The AO system serves two imaging magnetograph systems located at a new optical laboratory on the observatory's 2nd floor. The InfraRed Imaging Magnetograph (IRIM) is an innovative magnetograph system for near‐infrared (NIR) observations in the wavelength region from 1.0 μm to 1.6 μm. The Visible‐light Imaging Magnetograph (VIM) is basically a twin of IRIM for observations in the wavelength range from 550 nm to 700 nm. Both instruments were designed for high spatial and high temporal observations of the solar photosphere and chromosphere. Real‐time data processing is an integral part of the instruments and will enhance BBSO's capabilities in monitoring solar activity and predicting and forecasting space weather.  相似文献   

17.
Design of the Polarimeter for the Fibre Arrayed Solar Optical Telescope   总被引:1,自引:0,他引:1  
The theoretical design of the polarimeter used for the Fibre Arrayed Solar Optical Telescope (FASOT) is described. It has the following characteris- tics: (1) It is provided with the function of optical polarization switching, which makes the high-effciency polarimetry possible; (2) In the waveband of 750 nm, the polarimetric effciency is higher than 50% for the every Stokes parameter, and higher than 86.6% for the total polarization, thus an observer can make the simultaneous polarization measurements on multiple magnetosensitive lines in such a broad range of wavelength; (3) According to the selected photospheric and chromospheric lines, the measurement can be focused on either linear polarization or circular polarization; (4) The polarimeter has a loose tolerance on the manufacturing technology of polarimetric elements and installation errors. All this makes this polarimeter become a high-performance polarimetric device.  相似文献   

18.
136 stars which were known to be members of the open cluster NGC 752 were observed at the R band with the ROTSE–IIId telescope located at the Turkish National Observatory (TUG) site. The data had been evaluated together with BV and 2MASS photometric data. A new practical method for separating dwarf and giant was described and applied. Evaluating the colour magnitude–diagrams with Padova isochrones revealed for the open cluster NGC 752 a metallicity similar to the Sun and an age of 1.41 ± 0.20 Gyr. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

19.
We present the analysis of optical and X‐ray XMM‐Newton data of the source 4U 1344‐60. On the basis of the optical data we propose to classify 4U 1344‐60 as a Seyfert 1.5 galaxy and we measured a redshift value z = 0.012 ± 0.001. The observed X‐ray spectrum is complex. The continuum emission can be described as a power law obscured by two neutral absorption components. 4U 1344‐60 exhibits a broad and skewed iron line at 6.4 keV most likely originated in a few gravitational radius of an accretion disc. The analysis also reveals the presence of two narrow emission line‐like features at ∼4.9 keV and ∼5.3 keV. Assuming that hot spots on the surface of the accretion disc, orbiting very close to the black hole is responsible of these emission lines, the accretion disc would present an inclination of 20° and the active regions would be located in the 6–10 R g radius range. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

20.
We present monitoring analysis of 8 XMM‐Newton observations of the Seyfert 2 galaxy Mrk 3, spanning a period of ∼19 months. The continuum flux in the 3–12 keV band remains constant during this observing period. The X‐ray spectrum is well described, in agreement with previous works, by a highly absorbed (N H > 1024 cm–2) power law model, with a photon index Γ = 1.9 and a strong reflection component. A strong Fe Kα line at 6.4 keV with an equivalent width of ∼500 eV is detected in the X‐ray spectrum. When we consider the co‐added spectrum we also detect a weaker emission line at 7.4 keV corresponding to neutral Ni Kα emission and weak evidence for the presence of an ionized Fe Kα line at 6.7 keV. Direct comparison with the results obtained from an earlier XMM‐Newton observation of Mrk 3, shows a decrease in the continuum flux of ∼30 per cent followed by a similar decrease in the reflected component. Both emission line components at 6.4 and 6.7 keV do not vary. However we find that an alternative model where the N H varies by 20 per cent is also plausible. In this case both the continuum and the reflected emission do not change. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

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