Gotowe bibliografie tematyczne / Astrometric

Gotowa bibliografia na temat „Astrometric”

Autor: Grafiati
Data publikacji: 4 czerwca 2021
Data aktualizacji: 10 marca 2023

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Artykuły w czasopismach na temat "Astrometric"

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Klioner, S. A. "Relativistic astrometry and astrometric relativity". Proceedings of the International Astronomical Union 3, S248 (październik 2007): 356–62. http://dx.doi.org/10.1017/s174392130801956x.

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AbstractThe interplay between modern astrometry and gravitational physics is very important for the progress in both these fields. Below some threshold of accuracy, Newtonian physics fails to describe observational data and the Einstein's relativity theory must be used to model the data adequately. Many high-accuracy astronomical techniques have already passed this threshold. Moreover, modern astronomical observations cannot be adequately modeled if relativistic effects are considered as small corrections to Newtonian models. The whole way of thinking must be made compatible with relativity: this starts with the concepts of time, space and reference systems.An overview of the standard general-relativistic framework for modeling of high-accuracy astronomical observations is given. Using this framework one can construct a standard set of building blocks for relativistic models. A suitable combination of these building blocks can be used to formulate a model for any given type of astronomical observations. As an example the problem of four dimensional solar system ephemerides is exposed in more detail. The limits of the present relativistic formulation are also briefly summarized.On the other hand, high-accuracy astronomical observations play important role for gravitational physics itself, providing the latter with crucial observational tests. Perspectives for these astronomical tests for the next 15 years are summarized.
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Tubbs, R., N. M. Elias, R. Launhardt, S. Reffert, F. Delplancke, A. Quirrenbach, T. Henning i D. Queloz. "ESPRI data-reduction strategy and error budget for PRIMA". Proceedings of the International Astronomical Union 3, S248 (październik 2007): 132–33. http://dx.doi.org/10.1017/s1743921308018887.

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AbstractThe Exoplanet Search with PRIma (ESPRI) will use the PRIMA dual-feed astrometric capability on the Very Large Telescope Interferometer (VLTI) to perform astrometric detections of extra-solar planets. We present an overview of our data-reduction strategy for achieving 10-μarcsecond accuracy narrow-angle astrometry using the PRIMA instrument. We discuss the error budget for astrometric measurements, and those aspects of our strategy which are designed to minimise the astrometric measurement errors.
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Seidelmann, P. K. "Space Astrometry and the HST Wide Field/Planetary Camera". Symposium - International Astronomical Union 141 (1990): 347–54. http://dx.doi.org/10.1017/s0074180900087040.

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The launch of the Hipparcos spacecraft marked the beginning of space astrometry. Hopefully, this will be followed in the near future by the launch of the Hubble Space Telescope, which is not primarily an astrometric instrument, but has astrometric capabilities which will be described in this paper. In addition, there are plans and proposals for future astrometric spacecraft. These include the launch of a radio antenna, which combined with Earth-based antennae would provide a very, very long base line interferometer (Levy, 1986, 1988). There are proposals for launching optical interferometers, such as POINTS (Reasenberg et al 1988). There are also proposals by York and Gatewood (Gatewood et al., 1986; Gatewood 1987, 1989) for launching astrometric instruments using gratings and detectors. Thus, the future holds the prospects for a whole new capability in the field of astrometry.
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Sakai, N. "SYNERGY BETWEEN OPTICAL (GAIA) AND RADIO (VLBI)ASTROMETRIC RESEARCHES". Revista Mexicana de Astronomía y Astrofísica Serie de Conferencias 52 (5.10.2020): 9–11. http://dx.doi.org/10.22201/ia.14052059p.2020.52.03.

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Optical and radio astrometry have become significant for mapping the Milky Way. We introduce an example of synergy between optical and radio astrometry on a research of the Galactic spiral arms. Kinematics and spatial distribution of star and gas indicate a new and complex picture of the Galactic spiral arms. Synergy of astrometric study at multi-wavelength would be enhanced thanks to future infrared astrometric projects (e.g.,Small Jasmine; GaiaNIR) in 2020-2030s.
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Schilbach, E., Wenjing Jin, M. Crézé, P. D. Hemenway, I. I. Kumkova, I. K. Platais, S. Röser, C. Turon i J. J. Wang. "Commission 24: Photographic Astrometry: (Astrometrie Photographique)". Transactions of the International Astronomical Union 24, nr 1 (2000): 48–59. http://dx.doi.org/10.1017/s0251107x00002571.

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The scope of scientific interests of about 130 Commission members is much more complex than one may expect from the title of the commission. Besides traditional topics like the compilation of astrometric catalogues and the construction of an inertial reference system, more and more investigations performed by our members have been dedicated to the astrophysical interpretation of observations including among others astrometric data.
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Fey, Alan L. "Limits on Astrometric Accuracy". International Astronomical Union Colloquium 180 (marzec 2000): 20–28. http://dx.doi.org/10.1017/s0252921100000063.

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AbstractA general overview of the various factors limiting the accuracy to which astrometric observations can be made is presented. Since this is a very broad topic, it is limited primarily to radio astrometry of extragalactic objects.
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Hobbs, David, Berry Holl, Lennart Lindegren, Frédéric Raison, Sergei Klioner i Alexey Butkevich. "Determining PPN γ with Gaia's astrometric core solution". Proceedings of the International Astronomical Union 5, S261 (kwiecień 2009): 315–19. http://dx.doi.org/10.1017/s1743921309990561.

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AbstractThe ESA space astrometry mission Gaia, due for launch in early 2012, will in addition to its huge output of fundamental astrometric and astrophysical data also provide stringent tests of general relativity. In this paper we present an updated analysis of Gaia's capacity to measure the PPN parameter γ as part of its core astrometric solution. The analysis is based on small-scale astrometric solutions taking into account the simultaneous determination of stellar astrometric parameters and the satellite attitude. In particular, the statistical correlation between PPN γ and the stellar parallaxes is considered. Extrapolating the results to a full-scale solution using some 100 million stars, we find that PPN γ could be obtained to about 10−6, which is significantly better than today's best estimate from the Cassini mission of 2 × 10−5.
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Platais, I., A. L. Fey, S. Frey, S. G. Djorgovski, C. Ducourant, Ž. Ivezić, A. Rest, C. Veillet, R. F. G. Wyse i N. Zacharias. "Deep Astrometric Standards". Proceedings of the International Astronomical Union 3, S248 (październik 2007): 320–23. http://dx.doi.org/10.1017/s1743921308019455.

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AbstractThe advent of next-generation telescopes with very wide fields-of-view creates a need for deep and precise reference frames for astrometric calibrations. The Deep Astrometric Standards (DAS) program is designed to establish such a frame, by providing absolute astrometry at the 5–10 mas level in four 10 deg2 Galactic fields, to a depth of V=25. The source of our basic reference frame is the UCAC2 catalog, significantly improved by additional observations, and new VLBI positions of radio-loud and optically visible QSOs. We describe all the major steps in the construction of the DAS fields and provide the current status of this project.
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Zhang, Yigong, Jiancheng Wang, Jie Su, Xiangming Cheng i Zhenjun Zhang. "Astrometric Observations of a Near-Earth Object Using the Image Fusion Technique". Astronomical Journal 162, nr 6 (19.11.2021): 250. http://dx.doi.org/10.3847/1538-3881/ac2c6f.

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Abstract The precise astrometric observation of small near-Earth objects (NEOs) is an important observational research topic in the astrometric discipline, which greatly promotes multidisciplinary research, such as the origin and evolution of the solar system, the detection and early warning of small NEOs, and deep-space navigation. The characteristics of small NEOs, such as faintness and fast moving speed, restrict the accuracy and precision of their astrometric observations. In the paper, we present a method to improve the accurate and precise astrometric positions of NEOs based on image fusion technique. The noise analysis and astrometric test from the observed images of the open cluster M23 are given. Using the image fusion technique, we obtain the sets of superimposed images and original images containing reference stars and moving targets, respectively. The final fused image set includes background stars with high signal-to-noise ratios and ideal NEO images simultaneously and avoids the saturation of background stars. Using the fused images, we can reduce the influence of telescope tracking and NEO ephemeris errors on astrometric observations, and our results indicate that the accuracy and precision of NEO Eros astrometry are improved obviously after we choose suitable image fuse mode.
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Neuhäuser, R., A. Seifahrt, T. Röll, A. Bedalov i M. Mugrauer. "Detectability of Planets in Wide Binaries by Ground-Based Relative Astrometry with AO". Proceedings of the International Astronomical Union 2, S240 (sierpień 2006): 261–63. http://dx.doi.org/10.1017/s1743921307004139.

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AbstractMany planet candidates have been detected by radial-velocity variations of the primary star; they are planet candidates, because of the unknown orbit inclination. Detection of the wobble in the two other dimensions, to be measured by astrometry, would yield the inclination and, hence, true mass of the companions. We aim to show that planets can be confirmed or discovered in a close visual stellar binary system by measuring the astrometric wobble of the exoplanet host star as a periodic variation of the separation, even from the ground. We test the feasibility with HD 19994, a visual binary with one radial velocity planet candidate. We use the adaptive optics camera NACO at the VLT with its smallest pixel scale (∼ 13 mas) for high-precision astrometric measurements. The separations measured in 120 single images taken within one night are shown to follow white noise, so that the standard deviation can be divided by the square root of the number of images to obtain the precision. In this paper we present the first results and investigate the achievable precision in relative astrometry with adaptive optics. With careful data reduction it is possible to achieve a relative astrometric precision as low as 50 μ as for a 0″.6 binary with VLT/NACO observations in one hour, the best relative astrometric precision ever achieved with a single telescope from the ground. The relative astrometric precision demonstrated here with AO at an 8-m mirror is sufficient to detect the astrometric signal of the planet HD 19994 Ab as periodic variation of the separation between HD 19994 A and B.
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Rozprawy doktorskie na temat "Astrometric"

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O'Mullane, William. "Implementing the Gaia Astrometric Solution". Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/83861.

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As is the way with books in general this document is presented in the form of chapters (seven in number) devoted to individual topics relating to the overall topic of Gaia astrometric data processing. We progress logically from the satellite to the equations for the astrometry to the implementation of a software system to process Gaia observations. After this we look at a few key astrophysical issues for Gaia and explain tests which have been carried out, using the implementation, concerning these effects. A few appendices provide additional information. Here an overview paragraph is provided for each of the chapters: This introductory chapter Section 1 provides an overview of the work as well as an overview of the satellite hardware for the reader unfamiliar with Gaia. In Section 2 the equations underpinning the astrometric solution are explained and developed toward the algorithms actually coded in the system. Section 3 provides details of the Java software framework which hosts the equations previously described. The framework itself has been tuned to effectively process Gaia observations and is the main original content of the thesis. This system is known as the Astrometric Global Iterative Solution or AGIS. Having looked at the implementation, a few of the astrophysical effects and design decisions which influence the solution are described in Section 4. Although no data has yet been received from Gaia, extensive simulations have been performed in the Gaia community. Some of the AGIS tests relating to the astrophysical phenomena described in Section 4 are reported in Section 5. In this manner a demonstration of the effectiveness of AGIS is presented. A discussion and overview of the development approach adopted for A GIS is presented in Section 6. The eXtreme programming approach is particularly suited to science development and worked well for this project in the form presented. Brief conclusions are drawn in Section 7. Appendix A provides a primer on Quaternions which are used for attitude modelling. A complete list of the mind boggling acronyms used in this document appears in Appendix B. Finally some published papers are included in Appendix C.
Esta tesis presenta el marco numérico y computacional para la solución astrométrica Gaia. También cubre las consideraciones astrofísicas relativas a la solución y los aspectos relacionados con la gestión de la implementación de un sistema tan complejo.
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Bauer, Christina, of Western Sydney Nepean University i Faculty of Science and Technology. "Astrometric observations of wide southern double stars". THESIS_FST_XXX_Bauer_C.xml, 1995. http://handle.uws.edu.au:8081/1959.7/251.

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Observations were made of 309 binary systems between RA 17h - 07h and Dec -70 degrees to -60 degrees. The images were calibrated against pairs measured for CCD astometry. Measurements were made of separations, position angles and differential magnitudes. Uncertainties in position angle and separation were 7.8o/p and 0.16 arcseconds respectively. The position angles, separations and differential V magnitudes were compared with WDS figures. It was determined that only 29% _+ 5% of the observed pairs had undergone significant movement since the last previous measurement, which agrees with the results of a survey of the WDS. A statistical study of 1q77 pairs found that the spread of calculated separations agreed with those found by other authors, while the distribution of periods, while falling within the range(s) calculated by other authors, were significantly longer. A short-arc fitting program was tested using data derived from the published orbit of Centauri before being applied to seven observed pairs. Orbits could be calculated for six of the seven pairs. For four of these pairs the observed movement may be due to proper motion rather than orbital motion
Master of Science (Hons)
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Bauer, Christina. "Astrometric observations of wide southern double stars". Thesis, View thesis, 1995. http://handle.uws.edu.au:8081/1959.7/251.

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Observations were made of 309 binary systems between RA 17h - 07h and Dec -70 degrees to -60 degrees. The images were calibrated against pairs measured for CCD astometry. Measurements were made of separations, position angles and differential magnitudes. Uncertainties in position angle and separation were 7.8o/p and 0.16 arcseconds respectively. The position angles, separations and differential V magnitudes were compared with WDS figures. It was determined that only 29% _+ 5% of the observed pairs had undergone significant movement since the last previous measurement, which agrees with the results of a survey of the WDS. A statistical study of 1q77 pairs found that the spread of calculated separations agreed with those found by other authors, while the distribution of periods, while falling within the range(s) calculated by other authors, were significantly longer. A short-arc fitting program was tested using data derived from the published orbit of Centauri before being applied to seven observed pairs. Orbits could be calculated for six of the seven pairs. For four of these pairs the observed movement may be due to proper motion rather than orbital motion
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Bauer, Christina. "Astrometric observations of wide southern double stars /". View thesis, 1995. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030827.113613/index.html.

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Pasquato, Ester. "Effects of stellar surface inhomogeneities on astrometric accuracy". Doctoral thesis, Universite Libre de Bruxelles, 2011. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209872.

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Surface brightness asymmetries are a very common feature of stars. Among other effects they cause a difference between the projected centre of mass and the photocentre. The evolution of those surface features makes this difference time-dependent. In some cases the displacement can be a non-negligible fraction of the star radius R, and if R>1 AU, of the parallax. We investigate the impact of surface brightness asymmetries on the Gaia astrometric solution and on the data processing flow. In particular we derive analytical expressions for the change in the derived astrometric parameters for a single-star, with respect to the parameters for a uniformly-bright star, as a function of the characteristics of the surface brightness asymmetries. These predictions are confirmed by the results of the processing of simulated astrometric Gaia data where a photocentre motion caused by surface brightness asymmetries has been added using a Gaussian Markovian model.

In the case of a red supergiant star, the average photocentre shift is about 0.1 AU. Such a photocentric noise translates in a 10% inaccuracy on the parallax (independently of the distance), which becomes larger than the statistical error on the parallax derived from the data reduction for stars that are up to about 4 kpc away. For the most nearby stars, we derive an inaccuracy on the parallax that can be 10 times its statistical error. Finally we estimate that up to about 4000 stars among red supergiants and bright giants may have astrometric parameters that are inaccurate at levels bigger than expected because of the surface brightness asymmetries. In the determination of this number, a crucial role is played by the Gaia observable magnitude range. The fact that Gaia will not observe stars brighter than 5.6 in the Gaia G band means that the closest stars will not be observed. Yet, the impact of the surface brightness asymmetries is proportional to their angular size, meaning that the stars whose astrometric accuracy would be most affected are not observed.

Various non-Gaussian spot models (as applicable in the case of magnetic spots) have been implemented and analytical predictions for the effects of such magnetic spots are computed for the most representative classes of magnetic stars.

Another effect of the presence of surface brightness asymmetries is their impact on Gaia data processing flow. The quality of the fit of the data is evaluated with the F2 parameter that is a transformation of χ2 such that it has a unit normal distribution when the model is adequate and it is independent of the number of measurements. If the goodness-of-fit F2 of the single-star solution is not good enough (F2>3), a chain of solution of growing complexity is tried until a satisfactory one (with F2<3) is obtained. If no good solution is found, a so-called stochastic solution is computed where a "cosmic" error is added to the data in order to obtain a single-star solution with F2=0. We show that the photocentre noise induces an increase in the goodness-of-fit parameter, causing this chain of solutions to be entered. Depending on the characteristics of the photocentre noise, a variable fraction of the stars in our simulations end up with a non-single-star solution. Yet, we show that these (orbital) solutions are not acceptable because non-significant or non-physical. Finally, an important fraction of stars is assigned a stochastic solution with a cosmic noise matching well the photocentric noise.

/

Les asymétries de brillance de surface sont une caractéristique commune des étoiles. Parmi d'autres effets, elles provoquent une différence entre la projection du centre de masse et le photocentre. L'évolution de ces structures de surface rend cette différence variable avec le temps. Dans certains cas, le déplacement du photocentre peut être une fraction non négligeable du rayon de l'étoile R et, si R>1 UA, de la parallaxe. Nous examinons l'impact des asymétries de brillance de surface sur la solution astrométrique de Gaia et sur le processus de traitement des données. En particulier nous dérivons des expressions analytiques pour le changement des paramètres astrométriques déerivées pour une étoile simple, par rapport aux paramètres pour une étoile uniformément lumineuse, en fonction des caractéristiques des asymétries de brillance de surface. Ces prévisions sont confirmées par les résultats de simulations du traitement des données astrométriques de Gaia, auxquelles des mouvements du photocentre causés par des asymétries de brillance de surface ont été ajoutés en utilisant un modèle gaussien markovien.

Dans le cas d'une étoile super-géante rouge, le décalage moyen du photocentre est d'environ 0.1 UA. Un bruit photocentrique de cette amplitude se traduit dans une imprécision de 10% sur la parallaxe (indépendamment de la distance), qui peut devenir plus grande que l'erreur statistique sur la parallaxe déerivée par la réduction des données, pour les étoiles plus proches d'environ 4 kpc. Pour les étoiles les plus proches, nous évaluons une imprécision sur la parallaxe qui peut être 10 fois leur erreur statistique. Finalement, nous estimons que jusqu'à environ 4000 étoiles parmi les super-géantes rouges et géantes brillantes peuvent avoir des paramètres astrométriques inexactes à des niveaux plus grands que prévu en raison des asymétries de brillance de surface. Dans la détermination de ce nombre, la gamme de magnitudes observables par Gaia joue un rôle crucial. Le fait que Gaia n'observera pas les étoiles plus brillantes que 5.6 mag (en bande Gaia) signifie que les étoiles les plus proches ne seront pas observées. Pourtant, l'impact des asymétries de brillance de surface est proportionnel à leur taille angulaire, ce qui signifie que les étoiles dont la précision astrométrique seraient la plus affecté ne seront pas observées.

Différents modèles de taches ont été réalisés et des prédictions analytiques pour les effets de ces taches magnétiques sont calculés pour les classes les plus représentatives des étoiles magnétiques.

Un autre effet de la présence des asymétries de brillance de surface est leur impact sur le traitement des données de Gaia. La qualité de l'ajustement des données est évaluée avec le paramètre F2 qui est une transformation de χ2 telle qu'il ait une distribution normale lorsque le modèle est adéquat. Si la qualité de l'ajustement F2 de la solution étoile-simple n'est pas acceptable (F2>3), une chaîne de solutions de complexité croissante est essayée jusqu'à ce qu'une solution satisfaisante (avec F2<3) soit obtenue. Si aucune solution satisfaisante n'est trouvée, une solution dite stochastique est calculée où une erreur "cosmique" est ajoutée aux données afin d'obtenir une solution étoile-simple avec F2=0. Nous montrons que le bruit du photocentre induit une augmentation de F2, ce qui provoque l'activation de cette chaîne de solutions. Selon les caractéristiques du bruit du photocentre, une solution étoile-non-simple est obtenue pour une fraction variable des étoiles dans nos simulations. Nous montrons que ces solutions (orbitales) ainsi obtenues ne sont pas acceptables car non significatives ou non-physiques. Enfin, une fraction importante d'étoiles se voient attribuer une solution stochastique avec un bruit cosmique correspondant au bruit photocentrique.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Andrei, Alexandre Humberto. "Observed and predicted data in radio astrometric observations". Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279145.

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Colavita, Michael Mark. "Atmospheric limitations of a two-color astrometric interferometer". Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/15223.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1985.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.
Bibliography: leaves 381-389.
by Michael Mark Colavita.
Ph.D.
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Huang, Chunsheng. "Design and analysis of the Astrometric Telescope Facility". Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/184994.

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The Astrometric Telescope Facility (ATF) is designed to be a space-based facility searching for planets and extra solar planetary systems. In order to be able to positively identify other planetary systems such as Uranus/Neptune-class planets, the ATF is required to be capable of surveying approximately 100 stars within about 10 parsecs of the earth, of measuring a change in the relative position of stars to an accuracy of 10 microarcseconds, and of being stable for about 10 to 20 years. The ATF approach to astrometry is to modulate the intensity on the focal plane of the telescope by a moving Ronchi ruling or grating and then to determine the relative star positions from the phases of the modulated signals. This approach reduces boise from background stray light and reduces random noise by averaging over many measurements. The optical performance of the ATF system has been modeled mathematically using the concept of the system transfer function. Each subsystem has been studied analytically. The relationship between the measured parameter and aberrations of the system has been established analytically. Error sources from the system have been identified and calibration for the system is provided. Design and optimization for the astrometric telescope and gratings have been investigated. The key issues to reach the 10 microarcseconds are addressed.
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Eriksson, Urban. "Stellar Surface Structures and the Astrometric Serach for Exoplnaets". Licentiate thesis, Kristianstad University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-235229.

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Measuring stellar parallax, position and proper motion is the task of astrometry. With the development of new and much more accurate equipment, different noise sources are likely to affect the very precise measurements made with future instruments. Some of these sources are: stellar surface structures, circumstellar discs, multiplicity and weak microlensing. Also exoplanets may act as a source of perturbation. In this thesis I present an investigation of stellar surface structures as a practical limitation to ultra-high-precision astrometry. The expected effects in different regions of the HR-diagram are quantified. I also investigate the astrometric effect of exoplanets, since their astrometric detection will be possible with future projects such as Gaia and SIM PlanetQuest. Stellar surface structures like spots, plages and granulation produce small surface areas of different temperatures, i.e. of different brightness, which will influence integrated properties such as the total flux (zeroth moment of the brightness distribution), radial velocity and photocenter position (first moments of the brightness distribution). Also the third central moment of the brightness distribution, interferometrically observable as closure phase, will vary due to irregularities in the brightness distribution. All these properties have been modelled, using both numerical simulations and analytical methods, and statistical relations between the variations of the different properties have been derived. Bright and/or dark surface areas, randomly spread over the stellar surface, will lead to a binomial distribution of the number of visible spots and the dispersion of such a model will be proportional topN, where N is the number of spots or surface structures. The dispersion will also be proportional to the size of each spot, A. The dispersions of the integrated properties are therefore expected to be/ ApN. It is noted that the commonly used spot filling factor, f / AN, is notthe most relevant characteristic of spottiness for these effects. Both the simulations and the analytic model lead to a set of statistical relations for the dispersions or variations of the integrated properties. With ,e.g. knowledge of the photometric variation, m, it is possible to statistically estimate the dispersions for the other integrated properties. Especially interesting is the variation of the observed photocenter, i.e. the astrometric jitter. A literature review was therefore made of the observed photometric and radial-velocity variations for various types of stars. This allowed to map the expected levels of astrometric jitter across the HR diagram. From the models it is clear that for most stellar types the astrometric jitter due to stellar surface structures is expected to be of order 10 μAU or greater. This is more than the astrometric displacement typically caused by an Earth-sized exoplanet in the habitable zone of a long-lived main-sequence star, which is about 1–4 μAU. Only for stars with extremely low photometric variability (< 0.5 mmag) and low magnetic activity, comparable to that of the Sun, will the astrometric jitter be of order 1 μAU, sufficient to allow astrometric detection of an Earth-sized planet in the habitable zone. While stellar surface structure may thus seriously impair the astrometric detection of small exoplanets, it has in general negligible impact on the detection of large (Jupiter-size) planets.
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Brannigan, Emma Leigh. "A spectroscopic and spectro-astrometric study of T Tauri stars". Thesis, University of Hertfordshire, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440155.

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Książki na temat "Astrometric"

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Kopal, Zdeněk, i Jürgen Rahe, red. Astrometric Binaries. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-5343-7.

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Eichhorn, Heinrich K., i Robert J. Leacock, red. Astrometric Techniques. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4676-7.

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Charlie, Sobeck, i Ames Research Center, red. Astrometric telescope facility.: Preliminary systems definition study. Moffett Field, Calif: National Aeronautics and Space Administration, Ames Research Center, 1987.

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Alfano, Roberto. Astrometria Fotografica: Photographic Astrometry. Genoa, Italy: Genoa Astronomical Observatory, 1988.

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Robertson, Douglas Scott. Geodetic and astrometric measurements with very-long-baseline interferometry. [Rockville, Md.]: U.S. Department of Commerce, National Oceanic and Atmospheric Administratrion, 1985.

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C, Perryman M. A., European Space Agency i FAST Consortium, red. The Hipparcos and Tycho catalogues: Astrometric and photometric star catalogues derived from the ESA Hipparcos Space Astrometry Mission. Noordwijk, Netherlands: ESA Publications Division, 1997.

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Nishioka, Kenji. An astrometric facility for planetary detection on the space station. Moffett Field, Calif: National Aeronautics and Space Administration, Ames Research Center, 1987.

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C, Perryman M. A., Leeuwen Floor van 1952-, Guyenne T. D, Royal Greenwich Observatory i European Space Agency, red. Future possibilities for astrometry in space: A workshop organised jointly by the Royal Greenwich Observatory and the European Space Agency, Cambridge, UK, 19-21 June 1995. Noordwijk, The Netherlands: European Space Agency, 1995.

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United States. National Aeronautics and Space Administration., red. Astrometric observations of comets and asteroids and subsequent orbital investigations: Final report. [Washington, D.C.?: National Aeronautics and Space Administration, 1989.

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Marel, H. van der. On the "great circle reduction" in the data analysis for the astrometric satellite Hipparcos. Delft, The Netherlands: Rijkscommissie voor Geodesie, 1988.

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Części książek na temat "Astrometric"

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Benedict, G. Fritz. "Astrometric Planets". W Encyclopedia of Astrobiology, 113–15. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-11274-4_121.

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Latham, David W. "Astrometric Orbit". W Encyclopedia of Astrobiology, 113. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-11274-4_122.

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Benedict, G. Fritz, i Nader Haghighipour. "Astrometric Planets". W Encyclopedia of Astrobiology, 192–95. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-44185-5_121.

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Latham, David W., i Nader Haghighipour. "Astrometric Orbit". W Encyclopedia of Astrobiology, 191–92. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-44185-5_122.

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Colavita, M. M. "Astrometric Techniques". W Planets Outside the Solar System: Theory and Observations, 177–88. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-011-4623-4_13.

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Benedict, G. Fritz, i Nader Haghighipour. "Astrometric Planets". W Encyclopedia of Astrobiology, 1–4. Berlin, Heidelberg: Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-642-27833-4_121-8.

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Benedict, G. Fritz, i Nader Haghighipour. "Astrometric Planets". W Encyclopedia of Astrobiology, 1–4. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-27833-4_121-7.

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Latham, David W., i Nader Haghighipour. "Astrometric Orbit". W Encyclopedia of Astrobiology, 1. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-27833-4_122-3.

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Dommanget, J. "HIPPARCOS Astrometric Binaries". W Astrometric Binaries, 47–63. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-5343-7_5.

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Reasenberg, Robert D. "Microarcsecond Astrometric Interferometry". W Astrometric Techniques, 321–30. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4676-7_40.

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Streszczenia konferencji na temat "Astrometric"

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Hutter, Donald J. "USNO Astrometric Interferometer". W 1994 Symposium on Astronomical Telescopes & Instrumentation for the 21st Century, redaktor James B. Breckinridge. SPIE, 1994. http://dx.doi.org/10.1117/12.177229.

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Horner, Scott D., Marvin E. Germain, Frederick H. Harris, Mark S. Johnson, Kenneth J. Johnston, David G. Monet, Marc A. Murison i in. "Full-sky Astrometric Mapping Explorer: an optical astrometric survey mission". W Astronomical Telescopes and Instrumentation, redaktorzy James B. Breckinridge i Peter Jakobsen. SPIE, 2000. http://dx.doi.org/10.1117/12.394030.

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Phillips, James D. "Spectrometer for astrometric interferometry". W SPIE's 1995 Symposium on OE/Aerospace Sensing and Dual Use Photonics, redaktor Robert D. Reasenberg. SPIE, 1995. http://dx.doi.org/10.1117/12.212990.

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Swartz, Raymond. "The SIM astrometric grid". W Astronomical Telescopes and Instrumentation. SPIE, 2003. http://dx.doi.org/10.1117/12.460861.

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Cranney, Jesse, Israel Vaughn, Dionne Haynes, Trevor Mendel, Stephanie Monty, Davide Greggio, David Brodrick i François Rigaut. "MAVIS: astrometric calibration technique". W Adaptive Optics Systems VIII, redaktorzy Dirk Schmidt, Laura Schreiber i Elise Vernet. SPIE, 2022. http://dx.doi.org/10.1117/12.2629678.

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Vondrák, J., V. Štefka, Vasile Mioc, Cristiana Dumitrache i Nedelia A. Popescu. "Combination of space- and ground-based astrometric observations to create astrometric catalogs". W EXPLORING THE SOLAR SYSTEM AND THE UNIVERSE. AIP, 2008. http://dx.doi.org/10.1063/1.2993626.

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Busonero, Deborah. "Astrometric instrument modeling in the context of Gaia astrometric verification: tasks and activities". W SPIE Astronomical Telescopes + Instrumentation, redaktorzy George Z. Angeli i Philippe Dierickx. SPIE, 2012. http://dx.doi.org/10.1117/12.926703.

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Wiramihardja, S. D., M. I. Arifyanto, Y. Sugianto, C. Kunjaya, Manuel de León, D. M. de Diego i R. M. Ros. "Astrometric Study of Lo 1339". W MATHEMATICS AND ASTRONOMY: A JOINT LONG JOURNEY: Proceedings of the International Conference. AIP, 2010. http://dx.doi.org/10.1063/1.3506078.

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Phillips, James D., Robert W. Babcock, Marc A. Murison, Robert D. Reasenberg, Allen J. Bronowicki, Milton H. Gran, Charles F. Lillie, William McKinley i Robert J. Zielinski. "Newcomb: a small astrometric interferometer". W SPIE's 1995 Symposium on OE/Aerospace Sensing and Dual Use Photonics, redaktor Robert D. Reasenberg. SPIE, 1995. http://dx.doi.org/10.1117/12.212993.

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Korsch, Dietrich. "Design Optimization Of Astrometric Reflectors". W SPIE 1989 Technical Symposium on Aerospace Sensing, redaktor Dietrich G. Korsch. SPIE, 1989. http://dx.doi.org/10.1117/12.955570.

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Raporty organizacyjne na temat "Astrometric"

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Kaplan, G. H. A Comparison of Radio and Optical Astrometric Reduction Algorithms. Fort Belvoir, VA: Defense Technical Information Center, styczeń 1998. http://dx.doi.org/10.21236/ada423227.

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Perlmutter, S. An astrometric search for a stellar companion to the sun. Office of Scientific and Technical Information (OSTI), listopad 1986. http://dx.doi.org/10.2172/6484337.

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Taff, Laurence G. The Analysis of Near-Earth Satellite Astrometric Data at the ETS. Fort Belvoir, VA: Defense Technical Information Center, grudzień 1985. http://dx.doi.org/10.21236/ada163902.

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Tucker, Douglas. The Photometric and Astrometric Properties of DECam as Enablers of Precision Science. Office of Scientific and Technical Information (OSTI), styczeń 2018. http://dx.doi.org/10.2172/1460564.

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Johnston, K. J. Astrometry and Reference Frames. Fort Belvoir, VA: Defense Technical Information Center, sierpień 1999. http://dx.doi.org/10.21236/ada389881.

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Johnston, Kenneth J. The Future of Space Astrometry. Fort Belvoir, VA: Defense Technical Information Center, marzec 2000. http://dx.doi.org/10.21236/ada435796.

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Henry, Todd J., David G. Monet, Paul D. Shankland, Mark J. Reid, William van Altena i Norbert Zacharias. Ground-Based Astrometry 2010-2020. Fort Belvoir, VA: Defense Technical Information Center, styczeń 2010. http://dx.doi.org/10.21236/ada524845.

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Johnston, Kenneth J. Advances in Astrometry and Geophysics Made Possible by Radio Interferometry. Fort Belvoir, VA: Defense Technical Information Center, styczeń 1998. http://dx.doi.org/10.21236/ada400378.

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Winter, L. SIM Grid Star Observations: Astrometry With a New High Dynamic Range Imaging Device. Fort Belvoir, VA: Defense Technical Information Center, marzec 2000. http://dx.doi.org/10.21236/ada435793.

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