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  • Print publication year: 2012
  • Online publication date: December 2012

10 - Astrometry with ground-based diffraction-limited imaging

from Part III - Observing through the atmosphere

Summary

Introduction

The construction of large ground-based optical and infrared telescopes is driven by the desire to obtain astronomical measurements of both higher sensitivity and higher angular resolution. With each increase in telescope diameter the former goal, that of increased sensitivity, has been achieved. In contrast, the angular resolution of large telescopes (D > 1m), using traditional imaging, is limited not by the diffraction limit (θ ∼ λ/D), but rather by turbulence in the atmosphere. This is typically 1″, a factor of 10–20 times worse than the theoretical limit of a 4-meter telescope at near-infrared wavelengths. This angular resolution handicap has led to both space-based and ground-based solutions. With the launching of the Hubble Space Telescope (HST), a 2.4-m telescope equipped with both optical and infrared detectors, the astronomical community has obtained diffraction-limited images. These optical images, which have an angular resolution of ˜0.″1, have led to exciting new discoveries, such as the detection of a black hole in M87 (Ford et al. 1994) and protostellar disks around young stars in Orion (O'Dell et al. 1993, O'Dell and Wen 1994). However, HST has a modest-sized mirror diameter compared to the 8–10 meter mirror diameters of the largest ground-based telescope facilities.

With the development of techniques to overcome the wavefront distortions introduced by the Earth's atmosphere, diffraction-limited observations from the ground have become possible. These techniques cover a wide range of complexity and hence expense. Speckle imaging, which provided the earliest and simplest approach, is described in Sections 10.1 and 23.3.1 and adaptive optics, which has more recently become scientifically productive and which is a much more powerful technique, is discussed in Section 10.2.

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References
Babcock, H. W. (1953). The possibility of compensating astronomical seeing. PASP, 65, 229.
Balega, I. I. and Balega, Y. Y. (1988). Binary star measurements using digital speckle interferometer of 6-m telescope. JPRS Rep. Sci. Technol. USSR Space, 6, 508.
Balega, I. I., Balega, Y. Y., Hofmann, K.-H., et al. (2002). Speckle interferometry of nearby multiple stars. A&A, 385, 87.
Balega, I. I., Balega, Y. Y., Hofmann, K.-H., et al. (2006). Orbits of new Hipparcos binaries. II. A&A, 448, 703.
Brandner, W. and Koehler, R. (1998). Star formation environments and the distribution of binary separations. ApJ Lett, 499, 79.
Brandner, W., Alcala, J. M., Kunkel, M., Moneti, A., and Zinnecker, H. (1996). Multiplicity among T Tauri stars in OB and T associations. Implications for binary star formation. A&A, 307, 121.
Cady, E., Macintosh, B., Kasdin, N. J., and Soummer, R. (2009). Shared pupil design for the Gemini Planet Imager. ApJ, 698, 938.
Cameron, P. B., Britton, M. C., and Kulkarni, S. R. (2009). Precision astrometry with adaptive optics. AJ, 137, 83.
Do, T., Ghez, A. M., Morris, M. R., Yelda, S., et al. (2009a). A near-infrared variability study of the Galactic black hole: a red noise source with NO detected periodicity. ApJ, 691, 1021.
Do, T., Ghez, A., Morris, M. R., Lu, J. R., et al. (2009b). High angular resolution integralfield spectroscopy of the Galaxy's nuclear cluster: a missing stellar cusp?ApJ, 703, 1323.
Douglass, G. G., Hindsley, R. B., and Worley, C. E. (1997). Speckle interferometry at the US Naval Observatory. I. ApJ S, 111, 289.
Duchêne, G., Beust, H., Adjali, F., Konopacky, Q. M., and Ghez, A. M. (2006). Accurate stellar masses in the multiple system T Tauri. A&A, 457, L9.
Dupuy, T. J., Liu, M. C., and Ireland, M. J. (2009). Dynamical mass of the substellar benchmark binary HD 130948BC. ApJ, 692, 729.
Dyck, H. M., Simon, T., and Zuckerman, B. (1982). Discovery of an infrared companion to T Tauri. ApJ Lett, 255, 103.
Eckart, A. and Genzel, R. (1997). Stellar proper motions in the central 0.1 pc of the Galaxy. MNRAS, 284, 576.
Eckart, A., Genzel, R., Ott, T., and Schödel, R. (2002). Stellar orbits near Sagittarius A*. MNRAS, 331, 917.
Eckart, A., Baganoff, F. K., Schödel, R., et al. (2006). The flare activity of Sagittarius A*: new coordinated mm to X-ray observations. A&A, 450, 535.
Eisenhauer, F., Genzel, R., Alexander, T., et al. (2005). SINFONI in the Galactic center: young stars and infrared flares in the central light-month. ApJ, 628, 246.
Ford, H. C., et al. (1994). Narrowband HST images of M87: evidence for a disk of ionized gas around a massive black hole. ApJ Lett, 435, L27.
Fried, D. L. (1966). Optical resolution through a randomly inhomogeneous medium for very long and very short exposures. J. Optical Soc. America (1917–1983), 56, 1372.
Frogel, J. A., Alcock, C., Bolte, M., et al. (2009). Frontier science and adaptive optics on existing and next-generation telescopes. Astro 2010: The Astronomy and Astrophysics Decadal Survey, Position Papers, no. 16.
Fugate, R. Q., et al. (1994). J. Opt. Soc. Am.A, 11, 310.
Genzel, R., Eckart, A., Ott, T., and Eisenhauer, F. (1997). On the nature of the dark mass in the centre of the Milky Way. MNRAS, 291, 219.
Genzel, R., Schödel, R., Ott, T., et al. (2003). Near-infared flares from accreting gas around the supermassive black hole at the Galactic centre. Nature, 425, 934.
Ghez, A. M., Neugebauer, G., and Matthews, K. (1993). The multiplicity of T Tauri stars in the star forming regions Taurus–Auriga and Ophiuchus–Scoprius: a 2.2 micron speckle imaging survey. AJ, 106, 2005.
Ghez, A. M., Weinberger, A. J., Neugebauer, G., Matthews, K., and McCarthy, D. W. Jr., (1995). Speckle imaging measurements of the relative tangential velocities of the components of T Tauri binary stars. AJ, 110, 753.
Ghez, A. M., McCarthy, D. W., Patience, J. L., and Beck, T. L. (1997). The multiplicity of pre-main-sequence stars in southern star-forming regions. ApJ, 481, 378.
Ghez, A. M., Klein, B. L., Morris, M., and Becklin, E. E. (1998). High proper-motion stars in the vicinity of Sagittarius A*: evidence for a supermassive black hole at the center of our Galaxy. ApJ, 509, 678.
Ghez, A. M., Morris, M., Becklin, E. E., Tanner, A., and Kremenek, T. (2000). The accelerations of stars orbiting the Milky Way's central black hole. Nature, 407, 349.
Ghez, A. M., Duchene, G., Matthews, K., et al. (2003). The first measurement of spectral lines in a short-period star bound to the Galaxy's central black hole: a paradox of youth. ApJ Lett, 586, L127.
Ghez, A. M., Wright, S. A., Matthews, K., et al. (2004). Variable infrared emission from the supermassive black hole at the center of the Milky Way. ApJ Lett, 601, L159.
Ghez, A. M., Salim, S., Hornstein, S. D., et al. (2005a). Stellar orbits around the Galactic center. ApJ, 620, 744.
Ghez, A. M., Hornstein, S. D., Lu, J. R., et al. (2005b). The first laser guide star adaptive optics observations of the Galactic center: Sgr A*'s infrared color and the extended red emission in its vicinity. ApJ, 635, 1087.
Ghez, A., Salim, S., Weinberg, N. N., et al. (2008). Measuring distance and properties of the Milky Way's central supermassive black hole with stellar orbits. ApJ, 689, 1044.
Gillessen, S., Eisenhauer, F., Trippe, S., et al. (2009). Monitoring stellar orbits around the massive black hole in the Galactic center. ApJ, 692, 1075.
Haller, J.W., Rieke, M. J., Rieke, G. H., et al. (1996). Stellar kinematics and the black hole in the Galactic center. ApJ, 456, 194.
Hardy, J. W. (1991). Adaptive optics – a progress review. Proc. SPIE, 1542, 2.
Hartkopf, W. I., McAlister, H. A., and Franz, O. G. (1989). Binary star orbits from speckle interferometry. II – Combined visual–speckle orbits of 28 close systems. AJ, 98, 1014.
Henry, T. J. and McCarthy, D.W. Jr., (1990). A systematic search for brown dwarfs orbiting nearby stars. ApJ, 350, 334.
Henry, T. J. and McCarthy, D. W. Jr., (1993). The mass-luminosity for stars of mass 1.0 to 0.08 solar mass. AJ, 106, 773.
Hornstein, S. D., Matthews, K., Ghez, A. M., et al. (2007). A constant spectral index for Sagittarius A* during infrared/X-ray intensity variations. ApJ, 667, 900.
Köhler, R., Kunkel, M., Leinert, C., and Zinnecker, H. (2000). Multiplicity of X-ray selected T Tauri stars in the Scorpius–Centaurus OB association. A&A, 356, 541.
Konopacky, Q. M., Ghez, A. M., Barman, T. S., et al. (2010). High-precision dynamical masses of very low mass binaries. ApJ, 711, 1087.
Labeyrie, A. (1970). Attainment of diffraction limited resolution in large telescopes by Fourier analysing speckle patterns in star images. A&A, 6, 85.
Lacy, J. H., Townes, C. H., Geballe, T. R., and Hollenbach, D. J. (1980). Observations of the motion and distribution of the ionized gas in the central parsec of the Galaxy. II. ApJ, 241, 132.
Leinert, C., Zinnecker, H., Weitzel, N., et al. (1993). A systematic approach for young binaries in Taurus. A&A, 278, 129.
Leinert, C., Richichi, A., and Haas, M. (1997a). Binaries among Herbig Ae/Be stars. A&A, 318, 472.
Leinert, C., Henry, T., Glindemann, A., and McCarthy, D. W. Jr., (1997b). A search for companions to nearby southern M dwarfs with near-infrared speckle interferometry. A&A, 325, 159.
Liu, M. C., Dupuy, T. J., and Ireland, M. J. (2008). Keck laser guide star adaptive optics monitoring of 2MASS J15344984-2952274AB: first dynamical determination of a binary T dwarf. ApJ, 689, 436.
Lohmann, A. W., Weigelt, G., and Wirnitzer, B. (1983). Speckle masking in astronomy – triple correlation theory and applications. Appl. Opt., 22, 4028.
Lu, J. R., Ghez, A. M., Hornstein, S. D., Morris, M. R., Becklin, E. E., and Matthews, K. (2009). A disk of young stars at the Galactic center as determined by individual stellar orbits. ApJ, 690, 1463.
Maoz, D., Sternberg, A., and Ho, L. C. (1998). “Super star clusters” revealed in NICMOS images of circumnuclear rings. A&AS, 193, 7604.
Marois, C., Macintosh, B., Barman, T., et al. (2008). Direct imaging of multiple planets orbiting the star HR 8799. Science, 322, 1348.
Mason, B. D., Douglass, G. G., and Hartkopf, W. I. (1999). Binary star orbits from speckle interferometry. I. Improved orbital elements of 22 visual systems. AJ, 117, 1023.
Mason, B. D., Gies, D. R., Hartkopf, W. I., et al. (1998). ICCD speckle observations of binary stars. XIX – An astrometric/spectroscopic survey of O stars. AJ, 115, 821.
Mason, B. D., Hartkopf, W. I., and Wycoff, G. L. (2008). Speckle interferometry at the US Naval Obervatory. XIV. AJ, 136, 2223.
Max, C. E., Avicola, K., Brase, J. M., et al. (1994). Design, layout, and early results of a feasibility experiment for sodium-layer laser-guide-star adaptive optics. J. Opt. Soc. Am.A, 11, 813.
Max, C. E., Olivier, S. S., Friedman, H. W., et al. (1997). Image improvement from a sodium-layer laser guide star adaptive optics system. Science, 277, 1649.
McAlister, H. A. (1977). Speckle interferometric measurements of binary stars. I. ApJ, 215, 159.
McAlister, H. A., Hartkopf, W. I., Hutter, D. J., and Franz, O. G. (1987). ICCD speckle observations of binary stars. II – Measurements during 1982–1985 from the Kitt Peak 4 m telescope. AJ, 93, 688.
McAlister, H. A., Mason, B. D., Hartkopf, W. I., Roberts, L. C. Jr., and Shara, M. M. (1996). ICCD speckle observations of binary stars. XIV. A brief survey for duplicity among white dwarf stars. AJ, 112, 1169.
McCarthy, D. W. Jr., Henry, T. J., McLeod, B., and Christou, J. C. (1991). The low-mass companion of Gliese 22A – first results of the Steward Observatory infrared speckle camera. AJ, 101, 214.
McGinn, M. T., Sellgren, K., Becklin, E. E., and Hall, D. N. B. (1989). Stellar kinematics in the Galactic center. ApJ, 338, 824.
Meyer, L., Do, T., Ghez, A., et al. (2008). A 600 minute near-infrared light curve of Sagittarius A*. ApJ Lett, 688, L17.
Moretti, A., Piotto, G., Arcidiacono, C., et al. (2009). MCAO near-IR photometry of the globular cluster NGC 7388: MAD observations in crowded fields. A&A, 493, 539.
O'Dell, C. R. and Wen, Z. (1994). Postrefurbishment mission Hubble Space Telescope images of the core of the Orion Nebula: Proplyds, Herbig-Haro objects, and measurements of a circumstellar disk. ApJ, 436, 194.
O'Dell, C. R., Wen, Z., and Hu, X. (1993). Discovery of new objects in the Orion nebula on HST images – shocks, compact sources, and protoplanetary disks. ApJ, 410, 696.
Patience, J., Ghez, A. M., Reid, I. N., Weinberger, A. J., and Matthews, K. (1998). The multiplicity of the Hyades and its implications for binary star formation and evolution. AJ, 115, 1972.
Patience, J., Ghez, A. M., Reid, I. N., and Matthews, K. (2002). A high angular resolution multiplicity survey of the open clusters α Persi and Praesepe. AJ, 123, 1570.
Paumard, T., Genzel, R., Martins, F., et al. (2006). The two young star disks in the central parsec of the Galaxy: properties, dynamics, and formation. ApJ, 643, 1011.
Peterson, D. M., and Solensky, R. (1988). 51 Tauri and the Hyades distance modulus. ApJ, 333, 256.
Petr, M. G., Coude, Du Foresto V., Beckwith, S. V. W., Richichi, A., and McCaughrean, M. J. (1998). Binary stars in the Orion Trapezium cluster core. ApJ, 500, 825.
Preibisch, T., Balega, Y., Hofmann, K.-H., Weigelt, G., and Zinnecker, H. (1999). Multiplicity of the massive stars in the Orion Nebula cluster. New Astron., 4, 531.
Roddier, F. J., Anuskiewicz, J., Graves, J. E., Northcott, M. J., and Roddier, C. A. (1994). Adaptive optics at the University of Hawaii I: current performance at the telescope. Proc. SPIE, 2201, 2.
Schödel, R., Ott, T., Genzel, R., et al. (2002). A star in a 15.2-year orbit around the supermassive black hole at the centre of the Milky Way. Nature, 419, 694.
Schödel, R., Ott, T., Genzel, R., et al. (2003). Stellar dynamics in the central arcsecond of our Galaxy. ApJ, 596, 1015.
Sellgren, K., McGinn, M. T., Becklin, E. E., and Hall, D. N. B. (1990). Velocity dispersion and the stellar population in the central 1.2 parsecs of the Galaxy. ApJ, 359, 112.
Stolte, A., Ghez, A. M., Morris, M., et al., (2008). The proper motion of the Arches cluster with Keck laser-guide star adaptive optics. ApJ, 675, 1278.
Torres, G., Stefanik, R. P., and Latham, D. W. (1997). The Hyades binaries Theta 1 Tauri and Theta 2 Tauri: the distance to the cluster and the mass-luminosity relation. ApJ, 485, 167.
Weigelt, G. P. (1977). Modified astronomical speckle interferometry ‘speckle masking’. Opt. Commun., 21, 55.
Weigelt, G., Balega, Y., Preibisch, T., et al. (1999). Bispectrum speckle interferometry of the Orion Trapezium stars: detection of a close (33 mas) companion to Theta (1) ORI C. A&A, 347, L15.