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Letteratura scientifica selezionata sul tema "Near Infrared long-Baseline interferometry"

Autore: Grafiati

Pubblicato: 19 ottobre 2024

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Articoli di riviste sul tema "Near Infrared long-Baseline interferometry"

Pan, Xiaopei, Shri Kulkarni, Michael Shao e M. Mark Colavita. "Narrow-Angle and Wide-Angle Astrometry via Long Baseline Optical/Infrared Interferometers". Symposium - International Astronomical Union 166 (1995): 13–18. http://dx.doi.org/10.1017/s0074180900227769.

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Long baseline optical/infrared interferometers, such as the Mark III Stellar Interferometer1 on Mt. Wilson and the ASEPS-0 Testbed Interferometer2 on Palomar Mountain, California, have good capabilities for narrow-angle and wide-angle astrometry with very high precision. Using the Mark III Interferometer many spectroscopic binaries became “visual” for the first time. The measurement accuracy of angular separation is 0.2 mas, the smallest separation measured between two components is 2 mas, the maximum magnitude difference is 4 mag, and the smallest semimajor axis is 4 mas. Such high angular resolution and dynamic range have been used to determine stellar masses with precision of 2% and differential stellar luminosities to better than 0.05 mag for separations of less than 0.″2. For some binary stars, not only have the systems been resolved, but also the diameter of the primary component has been determined, yielding direct measurements of stellar effective temperature with high accuracy. For parallax determination, the precision is 1 mas or better and is unaffected by interstellar extinction. For wide-angle astrometry with the Mark III interferometer, the observation results yielded average formal 1σ errors for FK5 stars of about 10 mas. Presently a new infrared interferometer, the ASEPS-0 Testbed Interferometer on Palomar Mountain is under construction, and is being optimized to perform high accuracy narrow-angle astrometry using long baseline observations at 2.2 μm, with phase referencing for increased sensitivity. The goal is to demonstrate differential astrometric accuracies of 0.06–0.1 mas3 in order to allow for detection of extra-solar planets in the near future.

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Jankov, S. "Astronomical optical interferometry, II: Astrophysical results". Serbian Astronomical Journal, n. 183 (2011): 1–35. http://dx.doi.org/10.2298/saj1183001j.

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Optical interferometry is entering a new age with several ground- based long-baseline observatories now making observations of unprecedented spatial resolution. Based on a great leap forward in the quality and quantity of interferometric data, the astrophysical applications are not limited anymore to classical subjects, such as determination of fundamental properties of stars; namely, their effective temperatures, radii, luminosities and masses, but the present rapid development in this field allowed to move to a situation where optical interferometry is a general tool in studies of many astrophysical phenomena. Particularly, the advent of long-baseline interferometers making use of very large pupils has opened the way to faint objects science and first results on extragalactic objects have made it a reality. The first decade of XXI century is also remarkable for aperture synthesis in the visual and near-infrared wavelength regimes, which provided image reconstructions from stellar surfaces to Active Galactic Nuclei. Here I review the numerous astrophysical results obtained up to date, except for binary and multiple stars milliarcsecond astrometry, which should be a subject of an independent detailed review, taking into account its importance and expected results at microarcsecond precision level. To the results obtained with currently available interferometers, I associate the adopted instrumental settings in order to provide a guide for potential users concerning the appropriate instruments which can be used to obtain the desired astrophysical information.

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Wittkowski, Markus. "Round Table Summary: Stellar Interferometry as a Tool to Investigate Atmospheres and to Compare Observations with Models". Symposium - International Astronomical Union 210 (2003): 313–21. http://dx.doi.org/10.1017/s0074180900133455.

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Long-baseline interferometry at optical and near-infrared wavelengths is an emerging technology which is quickly becoming a useful tool to investigate stellar atmospheres and to compare observations with models. Stellar atmosphere models have so far mainly been constrained by comparisons with stellar spectra which are integrated over the stellar disks. Interferometric observations provide spatially and spectrally resolved information and can thus provide important complementary observational information which can be compared to model predictions. Here, I summarize the different aspects on this topic which were discussed at a round table on Thursday, June 20, 2002, during IAU Symposium 210. This summary gives an overview on discussed interferometric facilities and techniques, concepts to study atmospheres by optical interferometry, and particular classes of objects. We conclude that more frequent interactions between the efforts of atmosphere modelling and interferometric observations promise to lead to increased confidence in stellar model atmospheres and to further advancement of the field in the next years.

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Kraus, S., Th Preibisch e K. Ohnaka. "The inner gaseous accretion disk around a Herbig Be star revealed by near- and mid-infrared spectro-interferometry". Proceedings of the International Astronomical Union 3, S243 (maggio 2007): 337–44. http://dx.doi.org/10.1017/s1743921307009696.

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AbstractHerbig Ae/Be stars are pre-main-sequence stars of intermediate mass, which are still accreting material from their environment, probably via a disk composed of gas and dust. Here we present a recent study of the geometry of the inner (AU-scale) circumstellar region around the Herbig Be star MWC 147 using long-baseline interferometry. By combining for the first time near- and mid-infrared spectro-interferometry on a Herbig star, our VLTI/AMBER and VLTI/MIDI data constrain not only the geometry of the brightness distribution, but also the radial temperature distribution in the disk. The emission from MWC 147 is clearly resolved and has a characteristic physical size of ∼1.3 AU and ∼9 AU at 2.2 μm and 11 μm respectively. This increase in apparent size towards longer wavelengths is much steeper than predicted by analytic disk models assuming power-law radial temperature distributions. For a detailed modeling of the interferometric data and the spectral energy distribution of MWC 147, we employ 2-D frequency-dependent radiation transfer simulations. This analysis shows that passive irradiated Keplerian dust disks can easily fit the SED, but predict much lower visibilities than observed, so these models can clearly be ruled out. Models of a Keplerian disk with emission from an optically thick inner gaseous accretion disk (inside the dust sublimation zone), however, yield a good fit of the SED and simultaneously reproduce the observed near- and mid-infrared visibilities. We conclude that the near-infrared continuum emission from MWC 147 is dominated by accretion luminosity emerging from an optically thick inner gaseous disk, while the mid-infrared emission also contains strong contributions from the passive irradiated dust disk.

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Dexter, J. "Event horizon scale emission models for Sagittarius A*". Proceedings of the International Astronomical Union 9, S303 (ottobre 2013): 298–302. http://dx.doi.org/10.1017/s1743921314000775.

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AbstractVery long baseline interferometry observations at millimeter wavelengths have detected source structure in Sgr A* on event horizon scales. Near-infrared interferometry will achieve similar resolution in the next few years. These experiments provide an unprecedented opportunity to explore strong gravity around black holes, but interpreting the data requires physical modeling. I discuss the calculation of images, spectra, and light curves from relativistic MHD simulations of black hole accretion. The models provide an excellent description of current observations, and predict that we may be on the verge of detecting a black hole shadow, which would constitute the first direct evidence for the existence of black holes.

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Cruzalèbes, P., R. G. Petrov, S. Robbe-Dubois, J. Varga, L. Burtscher, F. Allouche, P. Berio et al. "A catalogue of stellar diameters and fluxes for mid-infrared interferometry★". Monthly Notices of the Royal Astronomical Society 490, n. 3 (7 ottobre 2019): 3158–76. http://dx.doi.org/10.1093/mnras/stz2803.

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Abstract We present the Mid-infrared stellar Diameters and Fluxes compilation Catalogue (MDFC) dedicated to long-baseline interferometry at mid-infrared wavelengths (3–13 $\mu$m). It gathers data for half a million stars, i.e. nearly all the stars of the Hipparcos-Tycho catalogue whose spectral type is reported in the SIMBAD data base. We cross-match 26 data bases to provide basic information, binarity elements, angular diameter, magnitude and flux in the near and mid-infrared, as well as flags that allow us to identify the potential calibrators. The catalogue covers the entire sky with 465 857 stars, mainly dwarfs and giants from B to M spectral types closer than 18 kpc. The smallest reported values reach 0.16 $\mu$Jy in L and 0.1 $\mu$Jy in N for the flux, and 2 microarcsec for the angular diameter. We build four lists of calibrator candidates for the L and Nbands suitable with the Very Large Telescope Interferometer (VLTI) sub- and main arrays using the MATISSE instrument. We identify 1621 candidates for L and 44 candidates for N with the Auxiliary Telescopes (ATs), 375 candidates for both bands with the ATs, and 259 candidates for both bands with the Unit Telescopes (UTs). Predominantly cool giants, these sources are small and bright enough to belong to the primary lists of calibrator candidates. In the near future, we plan to measure their angular diameter with 1 per cent accuracy.

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Petersen, Eric, e Charles Gammie. "Non-thermal models for infrared flares from Sgr A*". Monthly Notices of the Royal Astronomical Society 494, n. 4 (1 maggio 2020): 5923–35. http://dx.doi.org/10.1093/mnras/staa826.

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ABSTRACT Recent observations with mm very long baseline interferometry (mm-VLBI) and near-infrared (NIR) interferometry provide mm images and NIR centroid proper motion for Sgr A*. Of particular interest are the NIR flares that have more than an order of magnitude higher flux density than the quiescent state. Here, we model the flares using time-dependent, axisymmetric, general relativistic magnetohydrodynamic (GRMHD) simulations with an electron distribution function that includes a small, variable, non-thermal component motivated by magnetic reconnection models. The models simultaneously match the observed mm mean flux density, mm image size, NIR quiescent flux density, NIR flare flux density, and NIR spectral slope. They also provide a better fit to the observed NIR flux density probability density function than previously reported models by reproducing the power-law tail at high flux density, though with some discrepancy at low flux density. Further, our modelled NIR image centroid shows very little movement: centroid excursions of more than 10 μas (the resolution of GRAVITY) are rare and uncorrelated with flux.

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Wittkowski, Markus, David A. Boboltz, Malcolm D. Gray, Elizabeth M. L. Humphreys, Iva Karovicova e Michael Scholz. "Radio and IR interferometry of SiO maser stars". Proceedings of the International Astronomical Union 8, S287 (gennaio 2012): 209–16. http://dx.doi.org/10.1017/s1743921312006989.

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AbstractRadio and infrared interferometry of SiO maser stars provide complementary information on the atmosphere and circumstellar environment at comparable spatial resolution. Here, we present the latest results on the atmospheric structure and the dust condensation region of AGB stars based on our recent infrared spectro-interferometric observations, which represent the environment of SiO masers. We discuss, as an example, new results from simultaneous VLTI and VLBA observations of the Mira variable AGB star R Cnc, including VLTI near- and mid-infrared interferometry, as well as VLBA observations of the SiO maser emission toward this source. We present preliminary results from a monitoring campaign of high-frequency SiO maser emission toward evolved stars obtained with the APEX telescope, which also serves as a precursor of ALMA images of the SiO emitting region. We speculate that large-scale long-period chaotic motion in the extended molecular atmosphere may be the physical reason for observed deviations from point symmetry of atmospheric molecular layers, and for the observed erratic variability of high-frequency SiO maser emission.

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Christou, J. C. "Speckle Interferometry". Highlights of Astronomy 8 (1989): 561–62. http://dx.doi.org/10.1017/s1539299600008340.

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Speckle interferometry is a technique which utilizes the full diffraction-limited imaging potential of ground-based telescopes. Short exposure images, or specklegrams, with an exposure time less than that of the atmospheric correlation time (~5- 50 ms) preserve the high-spatial frequency information lost in long exposure imaging. In 1970, Labeyrie computed the power spectrum of a set of specklegrams and showed that they contained diffraction-limited information. Since then the field has grown with improvements in both instrumentation and the phase recovery algorithms necessary for imaging. It has been applied at both visible and near-infrared wavelengths although, until recently, the latter has used slit-scanning techniques with single pixel detectors because of the lack of array detectors. The current state of speckle interferometry has been well covered in the proceedings of two recent joint National Optical Astronomy Observatories – European Southern Observatory workshops on Interferometric Imaging in Astronomy (Oracle, 1987 & Garching, 1988).

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Choquet, É., J. Menu, G. Perrin, F. Cassaing, S. Lacour e F. Eisenhauer. "Comparison of fringe-tracking algorithms for single-mode near-infrared long-baseline interferometers". Astronomy & Astrophysics 569 (settembre 2014): A2. http://dx.doi.org/10.1051/0004-6361/201220223.

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Più fonti

Tesi sul tema "Near Infrared long-Baseline interferometry"

Ogden, Chad E. "A prototype visible to near-infrared spectrograph for the CHARA array a long-baseline stellar interferometer /". unrestricted, 2005. http://etd.gsu.edu/theses/available/etd-11282005-121433/.

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Thesis (Ph. D.)--Georgia State University, 2005.
Theo A. ten Brummelaar, committee chair; Brian D. Thoms, Todd J. Henry, William G. Bagnuolo, Douglas R. Gies, Harold A. McAlister, committee members. Author's name from thesis t.p. Electronic text (548 p. : ill.) : digital, PDF file. Description based on contents viewed June 27, 2007; title from title screen. Includes bibliographical references (p. 539-548).

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Ogden, Chad Elliott. "A Prototype Visible to Near-Infrared Spectrograph for the CHARA Array, a Long-Baseline Stellar Interferometer". Digital Archive @ GSU, 2006. http://digitalarchive.gsu.edu/phy_astr_diss/4.

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This work is a description of the Visible to near Infrared Spectrograph system for the CHARA array. The CHARA Array is a 6-telescope interferometer at the Mount Wilson Observatory in the mountains north of Pasadena, California. It combines the light from the 1-meter telescopes, and measures the visibility of the resulting interference fringes, which gives information about the source intensity distribution on the sky. The resolution of the instrument is proportional to the telescope separation, or baseline, divided by the wavelength. The VIS system operates in the 600-1000~nm wavelength range, a factor of 3 to 4 shorter than the standard operating wavelength at CHARA, 2.13 um. An introduction to interferometry is given, with a description of the CHARA Array. The effects of diffraction through the system combined with atmospheric turbulence are described, and the results of a computer model given. The VIS system design is described, and results of the first fringe data are presented, including system visibility and throughput estimates.

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Pourré, Nicolas. "Détection par interférométrie optique d'exoplanètes géantes jeunes à l'échelle de l'unité astronomique". Electronic Thesis or Diss., Université Grenoble Alpes, 2024. http://www.theses.fr/2024GRALY032.

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Les observations directes fournissent des informations capitales sur les systèmes exoplanétaires. Par l'analyse de la position des planètes à différentes époques, nous pouvons déterminer leur orbite et remonter à l'histoire dynamique des systèmes. Par l'analyse de leur spectre en émission, nous pouvons déterminer la température des exoplanètes ainsi que la composition chimique de leur atmosphère, contenant des traceurs de leur mécanisme de formation.Seulement, les observations directes sont actuellement limitées. Les limites de résolution angulaire nous permettent d'observer uniquement les exoplanètes les plus éloignées de leur étoile, généralement à plus de 10 unités astronomiques. Aussi, les limites de contraste avec l'étoile hôte nous permettent d'observer uniquement des exoplanètes géantes jeunes, de moins de 15 Myr, dont le rayonnement thermique infrarouge est encore fort du fait de leur formation récente. Pour mieux comprendre la formation et l'évolution des systèmes planétaires, ces limites doivent être repoussées pour permettre des observations directes de géantes gazeuses à l'échelle de l'unité astronomique.Depuis 2019, l'instrument GRAVITY installé sur le Very Large Telescope Interferometer au Chili permet d'observer des exoplanètes à des séparations angulaires jusqu'ici inatteignable par les instruments d'imagerie directe classique. Récemment, l'instrument a permis de réaliser les premières observations directes des planètes β Pictoris c et HD 206893 c, respectivement de 8.2 et 12.7 masses de Jupiter et à 2.7 et 3.5 unités astronomiques de leur étoile.Dès l'été 2024, la mise à jour GRAVITY+ va installer des nouvelles optiques adaptatives cruciales pour obtenir un meilleur contraste et réaliser des observations d'exoplanètes moins massives et plus proches de leur étoile. En 2026, le télescope spatial Gaia publiera une nouvelle liste d'exoplanètes découvertes autour de 2 unités astronomiques de leur étoile par méthode d'astrométrie absolue. GRAVITY+ sera un instrument de choix pour caractériser ces planètes, mesurer leur masse et leur spectre à des longueurs d'onde proche de 2 µm.Ma thèse consiste à comprendre les limites actuelles de l'instrument GRAVITY et à préparer la mise à jour GRAVITY+ afin de permettre l'observation directe de "Jupiters-jeunes'' au plus proche de leur étoile. Pour ceci, ma thèse s'est découpée en trois parties.Premièrement, j'ai analysé des données d'observations passées pour quantifier les limites actuelles de GRAVITY en contraste et séparation angulaire. J'ai pu déterminer que l'instrument nous permettait d'observer des exoplanètes 30 000 fois moins brillantes que leur étoile, et ce jusqu'à 50 milli-arcseconde.Deuxièmement, j'ai travaillé sur la réduction des données d'observations afin de comprendre la source de bruits systématiques qui polluent les spectre d'exoplanètes. J'ai pu déterminer à quelles conditions ces bruits apparaissent et leur impact sur les observations.Troisièmement, j'ai travaillé directement sur l'instrument à l'implémentation d'un mode haut-contraste pour GRAVITY+. Ce mode spécifique pour les observations d'exoplanètes implique une correction des aberrations optiques ainsi qu'un contrôle du front d'onde. Le mode haut-contraste limitera l'impact de la lumière des étoiles hôtes et donc d'observer des exoplanètes moins massives et moins jeunes.Dans les années à venir, la synergie entre Gaia et GRAVITY+ va permettre de caractériser finement de nombreuses exoplanètes géantes jeunes, et certainement transformer notre vision de la manière dont les systèmes planétaires se forment et comment ils évoluent
Direct observations provide key information about exoplanetary systems. By analyzing the position of planets at different times, we can determine their orbits and trace the dynamic history of the systems. By analyzing their emission spectra, we can determine the temperature of exoplanets, as well as the chemical composition of their atmosphere, containing tracers of their formation mechanism.However, direct observations are currently limited. Angular resolution limits allow us to observe only the exoplanets furthest from their star, generally more than 10 astronomical units away. Also, the limits of contrast with the host star mean that we can only observe young giant exoplanets, less than 15 Myr, whose infrared thermal radiation is still strong due to their recent formation. To better understand the formation and evolution of planetary systems, these limits must be pushed back to enable direct observations of gas giants on the scale of the astronomical unit.Since 2019, the GRAVITY instrument installed on the Very Large Telescope Interferometer in Chile has made it possible to observe exoplanets at angular separations previously unattainable by conventional direct imaging instruments. Recently, the instrument enabled the first direct observations of the planets β Pictoris c and HD 206893 c, respectively 8.2 and 12.7 masses from Jupiter and 2.7 and 3.5 astronomical units from their star.In summer 2024, the GRAVITY+ upgrade will install new adaptive optics crucial for obtaining better contrast and making observations of less massive exoplanets closer to their star. In 2026, the Gaia space telescope will publish a new list of exoplanets discovered around 2 astronomical units from their star using absolute astrometry. GRAVITY+ will be an instrument of choice for characterizing these planets, measuring their mass and spectrum at wavelengths close to 2 µm.My thesis involves understanding the current limitations of GRAVITY, and preparing the GRAVITY+ upgrade to enable direct observation of "young Jupiters" as close as possible to their star. My thesis was divided into three parts.Firstly, I analyzed data from archival observations to quantify GRAVITY's current limitations in contrast and angular separation. I was able to determine that we could observe exoplanets 30,000 times fainter than their star, down to 50 milli-arcseconds.Secondly, I worked on observational data reduction to understand the source of systematic noise that pollutes exoplanet spectra. I was able to determine the conditions under which these noises appear and their impact on observations.Thirdly, I worked directly on the instrument to implement a high-contrast mode for GRAVITY+. This specific mode for exoplanet observations involves optical aberration correction and wavefront control. The high-contrast mode will limit the impact of host starlight, enabling us to observe less massive and younger exoplanets.In the years to come, the synergy between Gaia and GRAVITY+ will allow us to finely characterize many young giant exoplanets, and certainly transform our vision of how planetary systems form and how they evolve

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Grellmann, Rebekka. "Massive star formation as seen by infrared long-baseline interferometry". Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-149346.

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Grellmann, Rebekka [Verfasser], e Thomas [Akademischer Betreuer] Preibisch. "Massive star formation as seen by infrared long-baseline interferometry / Rebekka Grellmann. Betreuer: Thomas Preibisch". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2012. http://d-nb.info/1027842380/34.

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Millan-Gabet, Rafael. "Investigation of Herbig Ae /Be stars in the near -infrared with a long baseline interferometer". 1999. https://scholarworks.umass.edu/dissertations/AAI9950188.

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We have conducted the first systematic study of Herbig Ae/Be stars using the technique of long baseline spatial interferometry in the near-infrared, with the objective of characterizing the distribution and properties of the circumstellar dust responsible for the excess near-infrared fluxes observed in these systems. The observations for this work have been conducted at the Infrared Optical Telescope Array (IOTA). The interferometer resolves the source of infrared excess in 11 of the 15 systems surveyed. A new binary, MWC 361-A, has been detected interferometrically for the first time. The visibility data for all the sources has been interpreted within the context of four models which represent the range of plausible representations for the brightness distribution of the source of excess emission: a Gaussian distribution, a narrow uniform ring, an accretion disk, and an infrared companion. We find that the sizes of the near-infrared emitting regions are larger than previously thought (0.5–5.9 AU). We also find that none of the sources (except the new binary) shows varying visibilities as the orientation of the interferometer baseline changes, indicative of circularly symmetric brightness distributions. The observed symmetry of the sources of near-infrared excess strongly favors, for the data taken as an ensemble, models in which the circumstellar dust is distributed in spherical envelopes (the Gaussian model) or thin shells (the ring model). This interpretation is supported by the result that the measured sizes, combined with the excess near-infrared fluxes, imply optically thin emission, as required by the fact that the central stars are optically visible. We also find that the measured sizes and brightness do not correlate strongly with the luminosity of the central star. Moreover, the same excess results from circumstellar structures that differ in size by more than a factor of two, and surround essentially identical stars. Therefore, different physical mechanisms for the near-infrared emission may be at work in different cases, or alternatively, a single underlying mechanism with the property that the same infrared excess is produced on very different physical scales. For this work, a new fringe detection system for near-infrared wavelengths based on a NICMOS3 array has been developed. The noise performance achieved is among the lowest known for this type of instrument, and results in magnitude limits for fringe detection at the IOTA of about 8 in J and H bands and 6.5 in K′ band.

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Capitoli di libri sul tema "Near Infrared long-Baseline interferometry"

Danchi, W. C., M. Bester, P. R. McCullough e C. H. Townes. "Infrared Long Baseline Interferometry". In Highlights of Astronomy, 563–64. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0977-9_89.

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Paresce, F. "Ground-Based Optical/IR Long Baseline Interferometry". In Infrared Space Interferometry: Astrophysics & the Study of Earth-Like Planets, 85–95. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5468-0_13.

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Atti di convegni sul tema "Near Infrared long-Baseline interferometry"

Rajagopal, Jayadev K., Ryan Lau, Isack Padilla, Stephen T. Ridgway, Choahan Cui, Brittany McClinton, Aqil Sajjad et al. "Towards quantum-enhanced long-baseline optical/near-IR interferometry". In Optical and Infrared Interferometry and Imaging IX, a cura di Stephanie Sallum, Joel Sanchez-Bermudez e Jens Kammerer, 58. SPIE, 2024. http://dx.doi.org/10.1117/12.3019518.

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Cheriton, Ross, Volodymyr Artyshchuk, Erin Tonita, Glen Herriot, Brent Carlson, Thushara Gunaratne, Zoran Ljusic et al. "Silicon photonic aperture synthesis for long baseline near-infrared interferometry". In Optical and Infrared Interferometry and Imaging IX, a cura di Stephanie Sallum, Joel Sanchez-Bermudez e Jens Kammerer, 31. SPIE, 2024. http://dx.doi.org/10.1117/12.3019093.

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Kuś, Arkadiusz. "Dual-wavelength, near-infrared holographic tomography". In Digital Holography and Three-Dimensional Imaging, W4A.33. Washington, D.C.: Optica Publishing Group, 2024. http://dx.doi.org/10.1364/dh.2024.w4a.33.

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Dual wavelength interferometry has a long history and broad range of applications in optical measurements of objects, which exhibit phase steps greater than the single measurement wavelength [1–3]. The use of two measurements at slightly different wavelengths allows to extend the measurement range. In case of holographic tomography, the standard measurement of large samples such as organoids fails due to large refractive index differences and phase unwrapping errors. The application of synthetic wavelength allows to decrease the values of phase of the scattered wave for the synthetic wavelength and thus apply Born approximation to objects that exceed the π/2 phase for each of the constituent measurements. In this work holographic tomography is performed with a swept laser source, which additionally allows to fine-tune the synthetic wavelength.

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Rau, Gioia, Kenneth G. Carpenter, Tabetha Boyajian, Michelle J. Creech-Eakman, Julianne Foster, Margarita Karovska, David Leisawitz et al. "Artemis-enabled stellar imager (AeSI): a Lunar long-baseline UV/optical imaging interferometer". In Optical and Infrared Interferometry and Imaging IX, a cura di Stephanie Sallum, Joel Sanchez-Bermudez e Jens Kammerer, 54. SPIE, 2024. http://dx.doi.org/10.1117/12.3028797.

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Merand, Antoine, Pascal Borde e Vincent Coude du Foresto. "A catalog of calibrator stars for 200-meter baseline near-infrared stellar interferometry". In SPIE Astronomical Telescopes + Instrumentation, a cura di Wesley A. Traub. SPIE, 2004. http://dx.doi.org/10.1117/12.550757.

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Noecker, M. C., R. W. Babcock, J. D. Phillips e R. D. Reasenberg. "POINTS: technology for micro-arcsecond optical astrometry". In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/oam.1992.fll1.

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We discuss the technology requirements for the POINTS optical interferometric instrument. Angular resolution of 5 × 10−6 arcsec (25 prad) by using an interferometer with a 2-m baseline requires internal distance metrology at the few picometer level and precise starlight fringe splitting. We have shown long term stability of two picometers in measurements on a Michelson-type distance gauge; we will soon test a design for point- to-point distance measurements. Full-aperture metrology of the starlight path has shown promising results with the first prototype zone-plate mirror, which diffracts part of the incident light to an auxiliary focus. Other applicable technological areas include broadband mirrors and beam splitters with stable phase shift and polarization properties, high-efficiency broadband detector arrays, thermally stable glasses and structural materials, integrated optics, a stable and robust laser source in the near infrared, supersmooth surfaces, and precision glass assemblies.

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Ireland, Michael J., Denis Defrère, Frantz Martinache, John Monnier, Julien Woillez, Peter G. Tuthill e Barnaby Norris. "Image-plane fringe tracker for adaptive-optics assisted long baseline interferometry". In Optical and Infrared Interferometry and Imaging VI, a cura di Antoine Mérand, Michelle J. Creech-Eakman e Peter G. Tuthill. SPIE, 2018. http://dx.doi.org/10.1117/12.2314393.

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Xu, Teng, Yonghui Hou, Zhongwen Hu, Fanghua Jiang, Zhen Wu, Huimin Kang e Wei Wei. "Development progress of the prototype long baseline optical interferometer in China". In Optical and Infrared Interferometry and Imaging VII, a cura di Antoine Mérand, Stephanie Sallum e Peter G. Tuthill. SPIE, 2020. http://dx.doi.org/10.1117/12.2562070.

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Hofmann, Karl-Heinz, Matthias Heininger, Dieter Schertl, Gerd Weigelt, Florentin Millour e Philippe Berio. "Image reconstruction method IRBis for optical/infrared long-baseline interferometry". In SPIE Astronomical Telescopes + Instrumentation, a cura di Fabien Malbet, Michelle J. Creech-Eakman e Peter G. Tuthill. SPIE, 2016. http://dx.doi.org/10.1117/12.2232369.

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Dooley, Jonathan, e Michelle Creech-Eakman. "Initial steps toward a new method of atmospheric characterization over long baseline arrays". In Optical and Infrared Interferometry and Imaging VI, a cura di Antoine Mérand, Michelle J. Creech-Eakman e Peter G. Tuthill. SPIE, 2018. http://dx.doi.org/10.1117/12.2313853.

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