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Browsing Artikler, rapporter og annet (fysikk og teknologi) by Issue Date
Now showing items 1-20 of 94
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Shumilov, O.I.; Henriksen, K.; Kasatkina, E.A.; Vashenyuk, E.V. (Journal article, 1996)[+][-]
Abstract: The lidar measurements at Verhnetulomski observatory (68.6¡N, 31.8¡E) at Kola peninsula detected a considerable increase of stratospheric aerosol concentration after the solar proton event of GLE (ground level event) type on the 16/02/84. This increase was located at precisely the same altitude range where the energetic solar protons lost their energy in the atmosphere. The aerosol layer formed precipitated quickly (1Ð2 km per day) during 18, 19, and 20 February 1984, and the increase of R(H) (backscattering ratio) at 17 km altitude reached 40% on 20/02/84. We present the model calculation of CN (condensation nuclei) altitude distribution on the basis of an ion-nucleation mechanism, taking into account the experimental energy distribution of incident solar protons. The meteorological situation during the event was also investigated. URI: http://hdl.handle.net/10037/554 File(s) in this item: 1
article.pdf (215.8Kb) -
Kleinman, S. J.; Solheim, Jan Erik; Nather, R. E.; Bruvold, A.; Winget, D. E.; Clemens, J. C.; Bradley, A.; Kanaan, A.; Claver, C. F.; Watson, T. K.; Yanagida, K.; Nitta, A.; Dixson, J. S.; Grauer, A. D.; Hine, B. P.; Fontaine, G.; Liebert, James; Sullivan, D. J.; Wickramasinghe, D. T.; Achilleos, N.; Mara, T. M. K.; Seetha, S.; Ashoka, B. N.; Leibowitz, E. M.; Moskalik, P.; Krzesi´nski, J.; O’Donoghue, D.; Kurtz, D. W.; Warner, B.; Martinez, Peter; Dolez, N.; Chevreton, M.; Barstow, M. A.; Kepler, S. O.; Giovannini, O.; Hansen, C. J.; Augusteijn, T. (Journal article; Tidsskriftartikkel; Peer reviewed, 10-Oct-1997)[+][-]
Abstract: The white dwarfs are promising laboratories for the study of cosmochronology and stellar evolution. Through observations of the pulsating white dwarfs, we can measure their internal structures and compositions, critical to understanding post main sequence evolution, along with their cooling rates, allowing us to calibrate their ages directly. The most important set of white dwarf variables to measure are the oldest of the pulsators, the cool DAVs, which have not previously been explored through asteroseismology due to their complexity and instability. Through a time-series photometry data set spanning ten years, we explore the pulsation spectrum of the cool DAV, G29–38 and find an underlying structure of 19 (not including multiplet components) normal-mode, probably ℓ = 1 pulsations amidst an abundance of time variability and linear combination modes. Modelling results are incomplete, but we suggest possible starting directions and discuss probable values for the stellar mass and hydrogen layer size. For the first time, we have made sense out of the complicated power spectra of a large-amplitude DA pulsator. We have shown its seemingly erratic set of observed frequencies can be understood in terms of a recurring set of normal-mode pulsations and their linear combinations. With this result, we have opened the interior secrets of the DAVs to future asteroseismological modelling, thereby joining the rest of the known white dwarf pulsators. Description: This is the authors' accepted version of the article. URI: http://hdl.handle.net/10037/2038 File(s) in this item: 1
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Lilensten, J.; Guio, Patrick; Kofman, W.; Bjørnå, Noralv (Journal article, 1998)[+][-]
Abstract: The plasma dispersion function and the reduced velocity distribution function are calculated numerically for any arbitrary velocity distribution function with cylindrical symmetry along the magnetic field. The electron velocity distribution is separated into two distributions representing the distribution of the ambient electrons and the suprathermal electrons. The velocity distribution function of the ambient electrons is modelled by a near-Maxwellian distribution function in presence of a temperature gradient and a potential electric field. The velocity distribution function of the suprathermal electrons is derived from a numerical model of the angular energy flux spectrum obtained by solving the transport equation of electrons. The numerical method used to calculate the plasma dispersion function and the reduced velocity distribution is described. The numerical code is used with simulated data to evaluate the Doppler frequency asymmetry between the up- and downshifted plasma lines of the incoherent-scatter plasma lines at different wave vectors. It is shown that the observed Doppler asymmetry is more dependent on deviation from the Maxwellian through the thermal part for high-frequency radars, while for low-frequency radars the Doppler asymmetry depends more on the presence of a suprathermal population. It is also seen that the full evaluation of the plasma dispersion function gives larger Doppler asymmetry than the heat flow approximation for Langmuir waves with phase velocity about three to six times the mean thermal velocity. For such waves the moment expansion of the dispersion function is not fully valid and the full calculation of the dispersion function is needed. URI: http://hdl.handle.net/10037/555 File(s) in this item: 1
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Manson, A.H.; Hall, Chris; Meek, C.E. (Journal article, 1998)[+][-]
Abstract: The spring of 1997 has represented a stable period of operation for the joint University of Tromsù / University of Saskatchewan MF radar, being between refurbishment and upgrades. We examine the horizontal winds from the February to June inclusive and also include estimates of energy dissipation rates derived from signal fading times and presented as upper limits on the turbulent energy dissipation rate, e. Here we address the periodicity in the dynamics of the upper mesosphere for time scales from hours to one month. Thus, we are able to examine the changes in the spectral signature of the mesospheric dynamics during the transition from winter to summer states. URI: http://hdl.handle.net/10037/556 File(s) in this item: 1
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Henriksen, K.; Rees, D.; Smith, R.W.; Signernes, F.; Brandstrom, U.; Harris, M.; Maskall, G. (Journal article, 1998)[+][-]
Abstract: Two Doppler imaging systems (DIS) or wide-field imaging Fabry-Perot interferometers (FPI), have recently been commissioned, one at the Auroral Station, Adventdalen, Longyearbyen, Svalbard, and the second at the IRF, Kiruna, Sweden. These instruments can provide wide-field (600 * 800 km) images of neutral wind flows in the upper thermosphere, by measuring the Doppler shift of the atomic oxygen forbidden near 630 nm, which is emitted from an altitude of approximately 240 km. From the instrument in Svalbard, at mid-winter, it is possible to observe the dayside polar cusp and the polar cap throughout the entire day, whereas from Kiruna, the night-time auroral oval is observable during the hours of darkness. Measurements of thermospheric dynamics from the DIS can be used in conjunction with observations of ionospheric plasma flows and thermal plasma densities by the EISCAT-Svalbard radar (ESR) and by EISCAT, along with other complementary observations by co-located instruments such as the auroral large-scale imaging system (ALIS). Such combined data sets will allow a wide range of scientific studies to be performed concerning the dynamical response of the thermosphere and ionosphere, and the important energetic and momentum exchange processes resulting from their complex interactions. These processes are particularly important in the immediate vicinity of the polar cusp and within the auroral oval. Early results from Svalbard in late 1995 will be discussed. The DIS in Kiruna observed two interesting geomagnetic disturbances in early 1997, the minor geomagnetic storm of 10, 11 January, and the disturbed period from 7–10 February. During these events, the thermospheric wind response showed some interesting departures from the average behaviour, which we attribute to the result of strong and variable Lorenz forcing (ion drag) and Joule and particle heating during these geomagnetic disturbances. URI: http://hdl.handle.net/10037/567 File(s) in this item: 1
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Lühr, H.; Hansen, T.L.; Rother, M.; Iyemori, T.; Lepping, R.P. (Journal article, 1998)[+][-]
Abstract: For the six months from 1 October 1993 to 1 April 1994 the recordings of the IMAGE magnetometer network have been surveyed in a search for large- amplitude travelling convection vortices (TCVs). The restriction to large amplitudes (>100 nT) was chosen to ensure a proper detection of evens also during times of high activity. Readings of all stations of the northern half of the IMAGE network were employed to check the consistency of the ground signature with the notation of a dual-vortex structure moving in an azimuthal direc- tion. Applying these stringent selection criteria we detected a total of 19 clear TCV events. The statistical properties of our selection resemble the expected char- acteristics of large-amplitude TCVs. New and unexpect- ed results emerged from the superposed epoch analysis. TCVs tend to form during quiet intervals embedded in moderately active periods. The occurrence of events is not randomly distributed but rather shows a clustering around a few days. These clusters recur once or twice every 27 days. Within a storm cycle they show up five to seven days after the commencement. With regard to solar wind conditions, we see the events occurring in the middle of the IMF sector structure. Large-amplitude TCVs seem to require certain conditions to make solar wind transients `geoeffective', which have the tendency to recur with the solar rotation period. URI: http://hdl.handle.net/10037/566 File(s) in this item: 1
article.pdf (347.3Kb) -
Østensen, R.; Burud, I.; Stabell, R.; Magain, P.; Courbin, F.; Refsda, S.; Remy, M.; Teuber, J. (Journal article; Tidsskriftartikkel; Peer reviewed, 09-Sep-1998)[+][-]
Abstract: The Einstein Cross, Q 2237+0305, has been photometrically observed in four bands on two successive nights at NOT (La Palma, Spain) in October 1995. Three independent algorithms have been used to analyse the data: an automatic image decomposition technique, a CLEAN algorithm and the new MCS deconvolution code. The photometric and astrometric results obtained with the three methods are presented. No photometric variations were found in the four quasar images. Comparison of the photometry from the three techniques shows that both systematic and random errors affect each method. When the seeing is worse than 1.′′0, the errors from the automatic image decomposition technique and the Clean algorithm tend to be large (0.04-0.1 magnitudes) while the deconvolution code still gives accurate results (1σ error below 0.04) even for frames with seeing as bad as 1.′′7. Reddening is observed in the quasar images and is found to be compatible with either extinction from the lensing galaxy or colour dependent microlensing. The photometric accuracy depends on the light distribution used to model the lensing galaxy. In particular, using a numerical galaxy model, as done with the MCS algorithm, makes the method less seeing dependent. Another advantage of using a numerical model is that eventual nonhomogeneous structures in the galaxy can be modeled. Finally, we propose an observational strategy for a future photometric monitoring of the Einstein Cross. Description: Dette er forfatternes aksepterte versjon. This is the author’s final accepted manuscript. URI: http://hdl.handle.net/10037/2128 File(s) in this item: 1
article.pdf (343.7Kb) -
Guio, Patrick; Lilensten, J. (Journal article, 1999)[+][-]
Abstract: In an incoherent scattering radar experiment, the spectral measurement of the so-called up- and downshifted electron plasma lines provides information about their intensity and their Doppler frequency. These two spectral lines correspond, in the backscatter geom- etry, to two Langmuir waves travelling towards and away from the radar. In the daytime ionosphere, the presence of a small percentage of photoelectrons produced by the solar EUV of the total electron population can excite or damp these Langmuir waves above the thermal equilibrium, resulting in an enhance- ment of the intensity of the lines above the thermal level. The presence of photo-electrons also modifies the dielectric response function of the plasma from the Maxwellian and thus influences the Doppler frequency of the plasma lines. In this paper, we present a high time-resolution plasma-line data set collected on the EISCAT VHF radar. The analysed data are compared with a model that includes the effect of a suprathermal electron population calculated by a transport code. By comparing the intensity of the analysed plasma lines data to our model, we show that two sharp peaks in the electron suprathermal distribution in the energy range 20±30 eV causes an increased Landau damping around 24.25 eV and 26.25 eV. We have identified these two sharp peaks as the effect of the photoionisation of N2 and O by the intense flux of monochromatic HeII radiation of wavelength 30.378 nm (40.812 eV) created in the chromospheric network and coronal holes. Furthermore, we see that what would have been interpreted as a mean Doppler drift velocity for a Maxwellian plasma is actually a shift of the Doppler frequency of the plasma lines due to suprathermal electrons. URI: http://hdl.handle.net/10037/557 File(s) in this item: 1
article.pdf (1.798Mb) -
Holt, J.M.; Grydeland, Tom; Erickson, P.J.; Gorczyca, A.M. (Journal article, 2000)[+][-]
Abstract: The Millstone Hill Incoherent Scatter Data Acquisition System (MIDAS) is based on an abstract model of an incoherent scatter radar. This model is implemented in a hierarchical software system, which serves to isolate hardware and low-level software implementation details from higher levels of the system. Inherent in this is the idea that implementation details can easily be changed in response to technological advances. MIDAS is an evolutionary system, and the MIDAS hardware has, in fact, evolved while the basic software model has remained unchanged. From the earliest days of MIDAS, it was realized that some functions implemented in specialized hardware might eventually be implemented by software in a general-purpose computer. MIDAS-W is the realization of this concept. The core component of MIDAS-W is a Sun Microsystems UltraSparc 10 workstation equipped with an Ultrarad 1280 PCI bus analog to digital (A/D) converter board. In the current implementation, a 2.25 MHz intermediate frequency (IF) is bandpass sampled at 1 s intervals and these samples are multicast over a high-speed Ethernet which serves as a raw data bus. A second workstation receives the samples, converts them to filtered, decimated, complex baseband samples and computes the lag-profile matrix of the decimated samples. Overall performance is approximately ten times better than the previous MIDAS system, which utilizes a custom digital filtering module and array processor based correlator. A major advantage of MIDAS-W is its flexibility. A portable, single-workstation data acquisition system can be implemented by moving the software receiver and correlator programs to the workstation with the A/D converter. When the data samples are multicast, additional data processing systems, for example for raw data recording, can be implemented simply by adding another workstation with suitable software to the high-speed network. Testing of new data processing software is also greatly simplified, because a workstation with the new software can be added to the network without impacting the production system. MIDAS-W has been operated in parallel with the existing MIDAS-1 system to verify that incoherent scatter measurements by the two systems agree. MIDAS-W has also been used in a high-bandwidth mode to collect data on the November, 1999, Leonid meteor shower. URI: http://hdl.handle.net/10037/550 File(s) in this item: 1
article.pdf (327.0Kb) -
Rietveld, Michael T.; Tereshchenko, E.D.; Brekke, Asgeir; Khudukon, B.Z.; Kozlova, M.O.; Evstafiev, O.V.; Nygren, T. (Journal article; Peer reviewed, 2000)[+][-]
Abstract: Results are shown from an experimental campaign where satellite scintillation was observed at three sites at high latitudes and, simultaneously, the F region plasma flow was measured by the nearby EISCAT incoherent scatter radar. The anisotropy parameters of field-aligned irregularities are determined from amplitude scintillation using a method based on the variance of the relative logarithmic amplitude. The orientation of the anisotropy in a plane perpendicular to the geomagnetic field is compared with the direction of F region plasma flow. The results indicate that in most cases a good agreement between the two directions is obtained. URI: http://hdl.handle.net/10037/559 File(s) in this item: 1
article.pdf (198.7Kb) -
Tereshchenko, E.D.; Rietveld, Michael T.; Kozlova, M.O.; Brekke, Asgeir; Evstafiev, O.V.; Khudukon, B.Z.; Nygren, T. (Journal article; Peer reviewed, 2000)[+][-]
Abstract: Results on heating the ionospheric F region above Tromsø, Norway are presented. The ionosphere was monitored by satellite tomography and amplitude scintillation methods as well as the EISCAT incoherent scatter radar. No effect of heating was observed in the daytime. In the evening and in the pre-midnight sector, noticeable tilts of the F region were observed during heating periods. The tilts overlapped the heating cone, where the electron density decreased and irregularities exceeding 10 km in size appeared. Between the heating periods the F layer was restored to its horizontal shape. The anisotropic parameters of small-scale irregularities with scale lengths of hundreds of metres were also determined. It was found that the perpendicular anisotropy points in the direction of F region plasma flow. In some cases the results can be explained by assuming that the small-scale irregularities were generated within the heating cone and drifted out of the heating region where they were subsequently observed. URI: http://hdl.handle.net/10037/560 File(s) in this item: 1
article.pdf (909.2Kb) -
Van Eyken, A.P.; Hall, Chris; Svenes, K.R. (Journal article; Peer reviewed, 2000)[+][-]
Abstract: In 1997, reliable operation of the EISCAT Svalbard Radar (ESR) was achieved and a rocket launching facility at Ny Ålesund on Svalbard (79°N, 12°E) (SVALRAK) was established. On 20 November, 1977, the first instrumented payload was launched from SVALRAK. Although the payload configuration had been flown many times previously from Andøya Rocket Range on the Norwegian mainland, this presented an unprecedented in situ determination of positive ion density over Svalbard. Simultaneously, ESR measured similar density profiles but in a higher altitude regime. We have combined the ESR measurements with ionosonde data to establish a calibration and subsequently combined the ground-based and in situ determined profiles to give a composite positive ion density profile from the mesosphere to the thermosphere. URI: http://hdl.handle.net/10037/587 File(s) in this item: 1
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Hansen, T.L.; Bremer, J.; Hoffmann, P. (Journal article, 2000)[+][-]
Abstract: Using observations with the ALOMAR SOUSY radar near Andenes (69.3°N, 16.0°E) from 1994 until 1997 polar mesosphere summer echoes (PMSE) have been investigated in dependence on geomagnetic K indices derived at the Auroral Observa- tory Tromsù (69.66°N, 18.94°E). During night-time and morning hours a significant correlation between the signal-to-noise ratio (SNR) of the radar results and the geomagnetic K indices could be detected with a maxi- mum correlation near midnight. The correlation be- comes markedly smaller in the afternoon and early evening hours with a minimum near 17 UT. This diurnal variation is in reasonable agreement with riometer absorption at Ivalo (68.55°N, 27.28°E) and can be explained by the diurnal variation of ionization due to precipitating high energetic particles. Therefore, a part of the diurnal PMSE variation is caused by this particle precipitation. The variability of the solar EUV varia- tion, however, has no significant influence on the PMSE during the observation period. URI: http://hdl.handle.net/10037/558 File(s) in this item: 1
article.pdf (180.4Kb) -
Solheim, Jan Erik; Chaty, S.; Haswell, C.A.; Østensen, R.; Hynes, R.I.; Shrader, C.R.; Cui, W.; Mauche, C.W.; Norton, A.J.; Geballe, T.R.; Ioannou, Z.; King, A.R. (Conference object; Konferansebidrag, 06-Feb-2001)[+][-]
Abstract: We report here on multiwavelength observations of the two new soft X-ray transients (SXTs) XTE J1859+226 and XTE J1118+480, which we observed with HST/RXTE/UKIRT. For XTE J1118+480 we also used EUVE since it is located at a very high galactic latitude and suffers from very low extinction. The two sources exhibited very different behaviour. XTE J1859+226 seems quite normal and therefore a good object for testing the accretion mechanisms in place during the outbursts, XTE J1118+480 is much more unusual because it exhibits i) a low X-ray to optical ratio and ii) a strong non-thermal contribution in the radio to optical domain, which is likely to be due to synchrotron emission. We concentrate here on the near-infrared (NIR) and optical observations of these two systems. URI: http://hdl.handle.net/10037/2035 File(s) in this item: 1
article.pdf (589.0Kb) -
Fynbo, J.U.; Østensen, R.; Gorosabe, J.; Solheim, Jan Erik; Dall, T.H.; Hjorth, J.; Pedersen, H.; Andersen, M.I.; Møller, P.; Holland, S.; Smail, I.; Kobayashi, N.; Rol, E.; Vreeswijk, P.; Vrba, F.; Burud, I.; Jensen, B.L.; Henden, A.; Thomsen, B.; Canzian, B.; Castro Cer´on, J.M.; Castro-Tirado, A.J.; Cline, T.; Goto, M.; Greiner, J.; Hanski, M.T.; Hurley, K.; Pursimo, T.; Lund, N.; Tanvir, N.; Terada, H. (Journal article; Tidsskriftartikkel, 11-Apr-2001)[+][-]
Abstract: We present the discovery of the Optical Transient (OT) of the long–duration gamma-ray burst GRB 000926. The optical transient was detected independently with the Nordic Optical Telescope and at Calar Alto 22.2 hours after the burst. At this time the magnitude of the transient was R = 19.36. The transient faded with a decay slope of about 1.7 during the first two days after which the slope increased abruptly (within a few hours) to about 2.4. The light-curve started to flatten off after about a week indicating the presence of an underlying extended object. This object was detected in a deep image obtained one month after the GRB at R=23.87±0.15 and consists of several compact knots within about 5 arcsec. One of the knots is spatially coincident with the position of the OT and hence most likely belongs to the host galaxy. Higher resolution imaging is needed to resolve whether all the compact knots belong to the host galaxy or to several independent objects. In a separate paper we present a discussion of the optical spectrum of the OT, and its inferred redshift (Møller et al. in prep.). Description: This is the authors' manuscript URI: http://hdl.handle.net/10037/2039 File(s) in this item: 1
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Østensen, R.; Solheim, Jan Erik; Johannessen, F. (Journal article; Tidsskriftartikkel, 09-Oct-2001)[+][-]
Abstract: We report the discovery of an eclipsing binary – HS 0705+6700 – being an sdB star with a faint companion. From its light curve the orbital period of 8263.87 s, the mass ratio of the system q = 0.28, the inclination of 84.◦4 and other system parameters are derived. The companion does not contribute to the optical light of the system except through a strong reflection effect. The semiamplitude of the radial velocity curve K1 = 85.8 kms−1 and a mass function of f(m) = 0.00626M⊙ are determined. A spectroscopic analysis of the blue spectra results in Teff = 28 800K, log g = 5.40, and log(nHe/nH) = −2.68. These characteristics are typical for sdB stars, as is its mass of 0.48M⊙. According to its mass (0.13M⊙) and radius (0.19R⊙), the companion is an M dwarf. The primary is in a core helium burning phase of evolution, and the system must have gone through a common envelope stage when the primary was near the tip of the red giant branch. Description: This is the authors' manuscript URI: http://hdl.handle.net/10037/2040 File(s) in this item: 1
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Hall, Chris (Journal article; Peer reviewed, 2002)[+][-]
Abstract: By measuring fading times of radar echoes from underdense meteor trails, it is possible to deduce the ambipolar diffusivities of the ions responsible for these radar echoes. It could be anticipated that these diffusivities increase monotonically with height akin to neutral viscosity. In practice, this is not always the case. Here, we investigate the capability of neutral turbulence to affect the meteor trail diffusion rate. URI: 1432-0576 (elektronisk) File(s) in this item: 1
article.pdf (205.2Kb) -
Hall, Chris; Manson, A.H.; Meek, C.; Hagan, M.; Koshyk, J.; Franke, S.; Fritts, D.; Hocking, W.; Igarashi, K.; MacDougall, J.; Riggin, D.; Vincent, R. (Journal article; Peer reviewed, 2002)[+][-]
Abstract: In an earlier paper (Manson et al., 1999a) tidal data (1990–1997) from six Medium Frequency Radars (MFR) were compared with the Global Scale Wave Model (GSWM, original 1995 version). The radars are located between the equator and high northern latitudes: Christmas Island (2° N), Hawaii (22° N), Urbana (40° N), London (43° N), Saskatoon (52° N) and Tromsø (70° N). Common harmonic analysis was applied, to ensure consistency of amplitudes and phases in the 75–95 km height range. For the diurnal tide, seasonal agreements between observations and model were excellent while for the semi-diurnal tide the seasonal transitions between clear solstitial states were less well captured by the model. Here the data set is increased by the addition of two locations in the Pacific-North American sector: Yamagawa 31° N, and Wakkanai 45° N. The GSWM model has undergone two additional developments (1998, 2000) to include an improved gravity wave (GW) stress parameterization, background winds from UARS systems and monthly tidal forcing for better characterization of seasonal change. The other model, the Canadian Middle Atmosphere Model (CMAM) which is a General Circulation Model, provides internally generated forcing (due to ozone and water vapour) for the tides. The two GSWM versions show distinct differences, with the 2000 version being either closer to, or further away from, the observations than the original 1995 version. CMAM provides results dependent upon the GW parameterization scheme inserted, but one of the schemes provides very useful tides, especially for the semi-diurnal component. URI: http://hdl.handle.net/10037/561 File(s) in this item: 1
article.pdf (4.031Mb) -
Solheim, Jan Erik; Barstow, M.A.; Binette, L.; Brosch, N.; Cheng, F-Z.; Dennefeld, M.; Gomez de Castro, A.I.; Haubold, H.; van der Hucht, K.A.; Kappelmann, N.; Martinez, P.; Ribak, E.N.; Moisheev, A.; Pagano, I.; Sahade, J.; Wamsteker, W.; Werner, K.; Becker-Ross, H.; Florek, S.; Shustov, B. (Conference object; Konferansebidrag, 17-Sep-2002)[+][-]
Abstract: The World Space Observatory is an unconventional space project proceeding via distributed studies. The present design, verified for feasibilty, consists of a 1.7-meter telescope operating at the second Largangian point of the Earth-Sun system. The focal plane instruments consist of three UV spectrometers covering the spectral band from Lyman alpha to the atmospheric cutoff with R~55,000 and offering long-slit capability over the same band with R~1,000. In addition, a number of UV and optical imagers view adjacent fields to that sampled by the spectrometers. Their performance compares well with that of HST/ACS and the spectral capabilities of WSO rival those of HST/COS. The WSO, as presently conceived, will be constructed and operated with the same distributed philosophy. This will allow as many groups and countries to participate, each contributing as much as feasible but allowing multi-national participation. Although designed originally with a conservative approach, the WSO embodies some innovative ideas and will allow a world-class mission to be realized with a moderate budget. URI: http://hdl.handle.net/10037/2042 File(s) in this item: 1
article.pdf (550.3Kb) -
Solheim, Jan Erik; Hernanza, M.; González-Riestra, R.; Wamsteker, W.; Shustov, B.; Barstow, M.; Brosch, N.; Fu-Zhen, C.; Dennefeld, M.; Dopita, M.; Gómez de Castro, A.I.; Kappelmannc, N.l.; Pagano, I.; Sahade, J.; Haubold, H.; Solheim, J.-E.; Martínezc, P. (Journal article; Tidsskriftartikkel, 5-Nov-2002)[+][-]
Abstract: We summarize the capabilities of the World Space Observatory (UV) Project (WSO/UV). An example of the importance of this project (with a planned launch date of 2007/8) for the study of Novae is given. URI: http://hdl.handle.net/10037/2037 File(s) in this item: 1
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