25 results on '"Naru Sadakuni"'
Search Results
2. Performance of the Gemini Planet Imager Non-Redundant Mask and spectroscopy of two close-separation binaries HR 2690 and HD 142527
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Tara Cotten, Abhijith Rajan, Mark S. Marley, Rebecca Oppenheimer, Franck Marchis, Inseok Song, Vanessa P. Bailey, Stanimir Metchev, James R. Graham, Pascale Hibon, Stephen J. Goodsell, Schuyler Wolff, Joanna Bulger, Robert J. De Rosa, S. Mark Ammons, Jeffrey Chilcote, René Doyon, Kimberly Ward-Duong, Alexandra Z. Greenbaum, Naru Sadakuni, Lisa Poyneer, Eric L. Nielsen, Dmitry Savransky, Andrew Cardwell, Anand Sivaramakrishnan, Katie M. Morzinski, Laurent Pueyo, Sandrine Thomas, Peter G. Tuthill, Adam C. Schneider, Christian Marois, Patrick Ingraham, Sloane Wiktorowicz, Katherine B. Follette, Maxwell A. Millar-Blanchaer, Gaspard Duchêne, Li-Wei Hung, Marshall D. Perrin, Bruce Macintosh, Fredrik T. Rantakyrö, Jennifer Patience, Quinn Konopacky, David Palmer, Benjamin L. Gerard, Rémi Soummer, Travis Barman, J. Kent Wallace, Jason J. Wang, Michael P. Fitzgerald, Paul Kalas, James E. Larkin, Julien Rameau, Anthony Cheetham, and Jérôme Maire
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Physics ,FOS: Physical sciences ,techniques: high angular resolution ,Astronomy ,Astronomy and Astrophysics ,instrumentation: adaptive optics ,01 natural sciences ,Exoplanet ,Astronomical instrumentation ,010309 optics ,Graduate research ,stars: individual (HR 2690, HD 142527) ,Space and Planetary Science ,0103 physical sciences ,Gemini Planet Imager ,National laboratory ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,010303 astronomy & astrophysics - Abstract
The Gemini Planet Imager (GPI) contains a 10-hole non-redundant mask (NRM), enabling interferometric resolution in complement to its coronagraphic capabilities. The NRM operates both in spectroscopic (integral field spectrograph, henceforth IFS) and polarimetric configurations. NRM observations were taken between 2013 and 2016 to characterize its performance. Most observations were taken in spectroscopic mode with the goal of obtaining precise astrometry and spectroscopy of faint companions to bright stars. We find a clear correlation between residual wavefront error measured by the AO system and the contrast sensitivity by comparing phase errors in observations of the same source, taken on different dates. We find a typical 5-$\sigma$ contrast sensitivity of $2-3~\times~10^{-3}$ at $\sim\lambda/D$. We explore the accuracy of spectral extraction of secondary components of binary systems by recovering the signal from a simulated source injected into several datasets. We outline data reduction procedures unique to GPI's IFS and describe a newly public data pipeline used for the presented analyses. We demonstrate recovery of astrometry and spectroscopy of two known companions to HR 2690 and HD 142527. NRM+polarimetry observations achieve differential visibility precision of $\sigma\sim0.4\%$ in the best case. We discuss its limitations on Gemini-S/GPI for resolving inner regions of protoplanetary disks and prospects for future upgrades. We summarize lessons learned in observing with NRM in spectroscopic and polarimetric modes., Comment: Accepted to AJ, 22 pages, 14 figures
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- 2019
3. 1–2.4 μm near-IR spectrum of the giant planet β Pictoris b obtained with the gemini planet imager
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Andrew Norton, Bruce Macintosh, James E. Larkin, Abhijith Rajan, Zachary H. Draper, James R. Graham, Li-Wei Hung, Quinn Konopacky, Jennifer Patience, Donald T. Gavel, Markus Hartung, Jérôme Maire, Robert J. De Rosa, Rebecca Oppenheimer, Travis Barman, Fredrik T. Rantakyrö, Maxwell A. Millar-Blanchaer, Julien Rameau, Stephen J. Goodsell, Schuyler Wolff, Adam Burrows, Rémi Soummer, Kimberly Ward-Duong, Patrick Ingraham, Katie M. Morzinski, Gaspard Duchene, David Palmer, Andrew Cardwell, Katherine B. Follette, J. Kent Wallace, Michael P. Fitzgerald, Jennifer Dunn, Vanessa P. Bailey, Andrew Serio, Brian J. Bauman, Sandrine Thomas, Dmitry Savransky, Paul Kalas, Leslie Saddlemyer, Adam C. Schneider, Jeffrey Chilcote, Lisa Poyneer, Anand Sivaramakrishnan, Pascale Hibon, Stanimir Metchev, Sebastian Bruzzone, Alexandra Z. Greenbaum, René Doyon, Christine Chen, Joanna Bulger, Inseok Song, Daren Dillon, Jason J. Wang, Tara Cotten, Darren Erikson, Eric L. Nielsen, Naru Sadakuni, Franck Marchis, Mark S. Marley, Jeffrey Vargas, Christian Marois, Sloane Wiktorowicz, Marshall D. Perrin, and Laurent Pueyo
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010504 meteorology & atmospheric sciences ,Brown dwarf ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,adaptive optics [instrumentation] ,Astronomy & Astrophysics ,01 natural sciences ,Luminosity ,0103 physical sciences ,Beta Pictoris ,Astrophysics::Solar and Stellar Astrophysics ,Gemini Planet Imager ,planetary systems ,010303 astronomy & astrophysics ,individual [stars] ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Physics ,Giant planet ,Astronomy and Astrophysics ,Radius ,Effective temperature ,Surface gravity ,13. Climate action ,Space and Planetary Science ,astro-ph.EP ,spectroscopic [techniques] ,Astrophysics::Earth and Planetary Astrophysics ,Astronomical and Space Sciences - Abstract
Using the Gemini Planet Imager (GPI) located at Gemini South, we measured the near-infrared (1.0-2.4 micron) spectrum of the planetary companion to the nearby, young star $\beta$ Pictoris. We compare the spectrum obtained with currently published model grids and with known substellar objects and present the best matching models as well as the best matching observed objects. Comparing the empirical measurement of the bolometric luminosity to evolutionary models, we find a mass of $12.9\pm0.2$ $\mathcal{M}_\mathrm{Jup}$, an effective temperature of $1724\pm15$ K, a radius of $1.46\pm0.01$ $\mathcal{R}_\mathrm{Jup}$, and a surface gravity of $\log g = 4.18\pm0.01$ [dex] (cgs). The stated uncertainties are statistical errors only, and do not incorporate any uncertainty on the evolutionary models. Using atmospheric models, we find an effective temperature of $1700-1800$ K and a surface gravity of $\log g = 3.5$-$4.0$ [dex] depending upon model. These values agree well with other publications and with "hot-start" predictions from planetary evolution models. Further, we find that the spectrum of $\beta$ Pic b best matches a low-surface gravity L2$\pm$1 brown dwarf. Finally comparing the spectrum to field brown dwarfs we find the the spectrum best matches 2MASS J04062677-381210 and 2MASS J03552337+1133437.
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- 2018
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4. Performance of the Gemini Planet Imager’s adaptive optics system
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Daren Dillon, David Palmer, Katherine B. Follette, Alexandra Z. Greenbaum, Dmitry Savransky, S. Mark Ammons, Pascale Hibon, Jason J. Wang, Bruce Macintosh, Marshall D. Perrin, Markus Hartung, Brian J. Bauman, Jean-Pierre Véran, Donald T. Gavel, Naru Sadakuni, Vanessa P. Bailey, Andrew Cardwell, Sandrine Thomas, Fredrik T. Rantakyrö, Anand Sivaramakrishnan, and Lisa Poyneer
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Physics ,Spatial filter ,business.industry ,Image quality ,Materials Science (miscellaneous) ,Bandwidth (signal processing) ,Astrophysics::Instrumentation and Methods for Astrophysics ,Spectral density ,Wavefront sensor ,01 natural sciences ,Industrial and Manufacturing Engineering ,Exoplanet ,010309 optics ,Optics ,0103 physical sciences ,Gemini Planet Imager ,Astrophysics::Earth and Planetary Astrophysics ,Business and International Management ,business ,Adaptive optics ,010303 astronomy & astrophysics ,Remote sensing - Abstract
The Gemini Planet Imager's adaptive optics (AO) subsystem was designed specifically to facilitate high-contrast imaging. A definitive description of the system's algorithms and technologies as built is given. 564 AO telemetry measurements from the Gemini Planet Imager Exoplanet Survey campaign are analyzed. The modal gain optimizer tracks changes in atmospheric conditions. Science observations show that image quality can be improved with the use of both the spatially filtered wavefront sensor and linear-quadratic-Gaussian control of vibration. The error budget indicates that for all targets and atmospheric conditions AO bandwidth error is the largest term.
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- 2016
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5. An M-dwarf star in the transition disk of Herbig HD 142527; Physical parameters and orbital elements
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Stephen J. Goodsell, Rebecca Oppenheimer, F. Rantakyrö, M. Bonnefoy, Marshall D. Perrin, Beth Biller, Th. Henning, James R. Graham, J. H. Girard, Isabelle Baraffe, Pascale Hibon, G. Chauvin, Andrew Cardwell, Anand Sivaramakrishnan, P. Ingraham, Alexandra Z. Greenbaum, Attila Juhasz, Myriam Benisty, Tim D. Pearce, Bruce Macintosh, J.-U. Pott, Eric E. Mamajek, Quinn Konopacky, Sylvestre Lacour, Laurent Pueyo, Anthony Cheetham, Johan Olofsson, Naru Sadakuni, S. Thomas, Sebastian Marino, Aurora Sicilia-Aguilar, Peter G. Tuthill, and University of St Andrews. School of Physics and Astronomy
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Protoplanetary disks ,Dwarf star ,NDAS ,FOS: Physical sciences ,Astrophysics ,visual [Binaries] ,Protoplanetary disk ,01 natural sciences ,0103 physical sciences ,QB Astronomy ,Astrophysics::Solar and Stellar Astrophysics ,010303 astronomy & astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics::Galaxy Astrophysics ,QB ,Physics ,Orbital elements ,010308 nuclear & particles physics ,Herbig Ae/Be ,Astronomy and Astrophysics ,Mass ratio ,Position angle ,Stars ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Orbital motion ,variables: T Tauri [Stars] ,Spectral energy distribution ,Astrophysics::Earth and Planetary Astrophysics ,Planet-disk interactions - Abstract
HD 142527A is one of the most studied Herbig Ae/Be stars with a transitional disk, as it has the largest imaged gap in any protoplanetary disk: the gas is cleared from 30 to 90 AU. The HD142527 system is also unique in that it has a stellar companion with a small mass compared to the mass of the primary star. This factor of ~20 in mass ratio between the two objects makes this binary system different from any other YSO. The HD142527 system could therefore provide a valuable test bed. This low-mass stellar object may be responsible for both the gap and dust trapping observed by ALMA at longer distances. We observed this system with the NACO and GPI instruments using the aperture masking technique. Aperture masking is ideal for providing high dynamic range even at very small angular separations. We present the spectral energy distribution for HD142527A and B. Brightness of the companion is now known from the R band up to the M' band. We also followed the orbital motion of HD 142527B over a period of more than two years. The SED of the companion is compatible with a T=3000+/-100K object in addition to a 1700K blackbody environment (likely a circus-secondary disk). From evolution models, we find that it is compatible with an object of mass 0.13+/-0.03Msun, radius 0.90+/-0.15Rsun, and age $1.0^{+1.0}_{-0.75}$Myr. This age is significantly younger than the age previously estimated for HD142527A. Computations to constrain the orbital parameters found a semi major axis of $140^{+120}_{-70}$mas, an eccentricity of 0.5+/-0.2, an inclination of 125+/-15 degrees, and a position angle of the right ascending node of -5+/-40 degrees. Inclination and position angle of the ascending node are in agreement with an orbit coplanar with the inner disk, not coplanar with the outer disk. Despite its high eccentricity, it is unlikely that HD142527B is responsible for truncating the inner edge of the outer disk., published in A&A; 8 pages
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- 2015
6. Discovery and spectroscopy of the young jovian planet 51 Eri b with the Gemini Planet Imager
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J. Brewster, Kimberly Ward-Duong, Tushar Mittal, J. Lee, Roman R. Rafikov, Naru Sadakuni, Daniel C. Fabrycky, R. Murray-Clay, Franck Marchis, Joanna Bulger, James E. Larkin, Li-Wei Hung, M. Johnson-Groh, James R. Graham, S. Thomas, Bruce Macintosh, Maria Teresa Ruiz, Inseok Song, Tara Cotten, Barry Zuckerman, Z. H. Draper, Dave Palmer, Rebekah I. Dawson, Jennifer Patience, Gaspard Duchêne, Michael R. Line, Sasha Hinkley, Julien Rameau, Stanimir Metchev, Fredrik T. Rantakyrö, Quinn Konopacky, Christine Chen, Christian Marois, Katherine B. Follette, A. Z. Greenbaum, Abhijith Rajan, Jérôme Maire, Steven V. W. Beckwith, Sloane J. Wiktorowicz, Sebastian Bruzzone, René Doyon, Pauline Arriaga, Jeffrey Chilcote, J. J. Fortney, Marshall D. Perrin, Anand Sivaramakrishnan, Didier Saumon, Jean-Baptiste Ruffio, Étienne Artigau, Claire E. Max, Thomas M. Esposito, Max Millar-Blanchaer, Rebecca Oppenheimer, Dmitry Savransky, P. Hibon, Schuyler Wolff, Adam Burrows, R. J. De Rosa, Katie M. Morzinski, Patricio Rojo, Travis Barman, Rémi Soummer, David Lafrenière, Brenda C. Matthews, Ben Burningham, Alex Rudy, Caroline V. Morley, Jason J. Wang, Leslie Saddlemyer, Laurent Pueyo, Douglas Long, Michael P. Fitzgerald, S. Goodsell, M. Salama, Eugene Chiang, Paul Kalas, Mark Ammons, Mark S. Marley, James K. Wallace, Emily L. Rice, Ruobing Dong, Eric L. Nielsen, B. L. Gerard, Patrick Ingraham, Adam C. Schneider, Lisa Poyneer, Gautam Vasisht, and Rahul Patel
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spectroscopy ,photometry ,010504 meteorology & atmospheric sciences ,near infrared spectroscopy ,General Science & Technology ,Astrophysics::High Energy Astrophysical Phenomena ,sun ,Astronomical unit ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,telescope ,01 natural sciences ,Spectral line ,Jovian ,Photometry (optics) ,Planet ,water vapor ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Gemini Planet Imager ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Multidisciplinary ,luminance ,methane ,imaging method ,Astronomy ,molecular weight ,planetary evolution ,Effective temperature ,contrast ,Exoplanet ,astronomy ,air temperature ,planet ,13. Climate action ,Jupiter ,astro-ph.EP ,Astrophysics::Earth and Planetary Astrophysics ,absorption ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Directly detecting thermal emission from young extrasolar planets allows measurement of their atmospheric composition and luminosity, which is influenced by their formation mechanism. Using the Gemini Planet Imager, we discovered a planet orbiting the \$sim$20 Myr-old star 51 Eridani at a projected separation of 13 astronomical units. Near-infrared observations show a spectrum with strong methane and water vapor absorption. Modeling of the spectra and photometry yields a luminosity of L/LS=1.6-4.0 x 10-6 and an effective temperature of 600-750 K. For this age and luminosity, "hot-start" formation models indicate a mass twice that of Jupiter. This planet also has a sufficiently low luminosity to be consistent with the "cold- start" core accretion process that may have formed Jupiter., Comment: 29 pages, 3 figures, 2 tables, and Supplementary Materials. published in Science Express on Aug 13 2015. List of authors and the magnitudes of the star were correted
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- 2015
7. β PICTORIS’ INNER DISK IN POLARIZED LIGHT AND NEW ORBITAL PARAMETERS FOR β PICTORIS b
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Schuyler Wolff, Kimberly Ward-Duong, Gaspard Duchene, Eric L. Nielsen, James R. Graham, Fredrik T. Rantakyrö, Tara Cotten, Alexandra Z. Greenbaum, S. Mark Ammons, Rémi Soummer, Rebekah I. Dawson, Robert J. De Rosa, Katherine B. Follette, Bruce Macintosh, Anand Sivaramakrishnan, Abhijith Rajan, Markus Hartung, James E. Larkin, Katie M. Morzinski, Rebecca Oppenheimer, Christian Marois, Franck Marchis, David Palmer, Quinn Konopacky, Jean-Baptiste Ruffio, Jennifer Dunn, Laurent Pueyo, Andrew Cardwell, J. Kent Wallace, Gautam Vasisht, David Vega, Sandrine Thomas, Sasha Hinkley, Rebecca Jensen-Clem, Christine Chen, Pascale Hibon, Adam C. Schneider, Thomas M. Esposito, Sloane Wiktorowicz, Marshall D. Perrin, Mark S. Marley, Jason J. Wang, Douglas Long, Eugene Chiang, Jeffrey Chilcote, Zachary H. Draper, Dae-Sik Moon, Leslie Saddlemyer, Maxwell A. Millar-Blanchaer, Paul Kalas, Travis Barman, Michael P. Fitzgerald, Jérôme Maire, Patrick Ingraham, Lisa Poyneer, Naru Sadakuni, and Stephen J. Goodsell
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Stellar mass ,Density model ,Astrophysics ,Astronomy & Astrophysics ,Physical Chemistry ,Atomic ,Particle and Plasma Physics ,polarimetric [techniques] ,Disk image ,Phase function ,Nuclear ,Astrophysics::Galaxy Astrophysics ,planet–disk interactions ,Physics ,Orbital elements ,Debris disk ,planet-disk interactions ,Scattering ,techniques-polarimetric ,Molecular ,Astronomy and Astrophysics ,Position angle ,Space and Planetary Science ,individual [planets and satellites] ,Physics::Space Physics ,astro-ph.EP ,astrometry ,Astrophysics::Earth and Planetary Astrophysics ,planets and satellites-individual (β Pic b) ,Astronomical and Space Sciences ,Physical Chemistry (incl. Structural) - Abstract
Author(s): Millar-Blanchaer, MA; Graham, JR; Pueyo, L; Kalas, P; Dawson, RI; Wang, J; Perrin, MD; Moon, DS; Macintosh, B; Ammons, SM; Barman, T; Cardwell, A; Chen, CH; Chiang, E; Chilcote, J; Cotten, T; Rosa, RJD; Draper, ZH; Dunn, J; Duchene, G; Esposito, TM; Fitzgerald, MP; Follette, KB; Goodsell, SJ; Greenbaum, AZ; Hartung, M; Hibon, P; Hinkley, S; Ingraham, P; Jensen-Clem, R; Konopacky, Q; Larkin, JE; Long, D; Maire, J; Marchis, F; Marley, MS; Marois, C; Morzinski, KM; Nielsen, EL; Palmer, DW; Oppenheimer, R; Poyneer, L; Rajan, A; Rantakyro, FT; Ruffio, JB; Sadakuni, N; Saddlemyer, L; Schneider, AC; Sivaramakrishnan, A; Soummer, R; Thomas, S; Vasisht, G; Vega, D; Wallace, JK; Ward-Duong, K; Wiktorowicz, SJ; Wolff, SG | Abstract: We present H-band observations of β Pic with the Gemini Planet Imager's (GPI's) polarimetry mode that reveal the debris disk between ∼0.″3 (6 AU) and ∼1.″7 (33 AU), while simultaneously detecting β Pic b. The polarized disk image was fit with a dust density model combined with a Henyey-Greenstein scattering phase function. The best-fit model indicates a disk inclined to the line of sight () with a position angle (PA) (slightly offset from the main outer disk, ), that extends from an inner disk radius of to well outside GPI's field of view. In addition, we present an updated orbit for β Pic b based on new astrometric measurements taken in GPI's spectroscopic mode spanning 14 months. The planet has a semimajor axis of , with an eccentricity The PA of the ascending node is offset from both the outer main disk and the inner disk seen in the GPI image. The orbital fit constrains the stellar mass of β Pic to Dynamical sculpting by β Pic b cannot easily account for the following three aspects of the inferred disk properties: (1) the modeled inner radius of the disk is farther out than expected if caused by β Pic b; (2) the mutual inclination of the inner disk and β Pic b is when it is expected to be closer to zero; and (3) the aspect ratio of the disk () is larger than expected from interactions with β Pic b or self-stirring by the disk's parent bodies.
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- 2015
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8. Gemini Planet Imager Observations of the AU Microscopii Debris Disk: Asymmetries within One Arcsecond
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S. Mark Ammons, James R. Graham, René Doyon, Abhijith Rajan, Andrew Cardwell, Sandrine Thomas, Robert J. De Rosa, Stephen J. Goodsell, Schuyler Wolff, Andrew Serio, Li-Wei Hung, Brenda C. Matthews, Katie M. Morzinski, Christine Chen, Jérôme Maire, Thomas M. Esposito, Kimberly Ward-Duong, Sloane J. Wiktorowicz, Laurent Pueyo, Jeffrey Chilcote, Naru Sadakuni, Markus Hartung, Zachary H. Draper, Gaspard Duchêne, Marshall D. Perrin, Fredrik T. Rantakyrö, Franck Marchis, Joanna Bulger, Eugene Chiang, Anand Sivaramakrishnan, Pascale Hibon, Christian Marois, Bruce Macintosh, Jason J. Wang, Eric L. Nielsen, Jennifer Patience, Max Millar-Blanchaer, Alexandra Z. Greenbaum, Michael P. Fitzgerald, Paul Kalas, James E. Larkin, Patrick Ingraham, Rémi Soummer, Rebecca Oppenheimer, and Sasha Hinkley
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Brightness ,010504 meteorology & atmospheric sciences ,FOS: Physical sciences ,Astrophysics ,adaptive optics [instrumentation] ,Astronomy & Astrophysics ,circumstellar matter ,01 natural sciences ,Submillimeter Array ,Planet ,0103 physical sciences ,data analysis [methods] ,Gemini Planet Imager ,Surface brightness ,010303 astronomy & astrophysics ,individual [stars] ,Space Telescope Imaging Spectrograph ,0105 earth and related environmental sciences ,Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,planet-disk interactions ,Debris disk ,high angular resolution [techniques] ,Astronomy and Astrophysics ,Space and Planetary Science ,astro-ph.EP ,Planetary mass ,Astronomical and Space Sciences ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We present Gemini Planet Imager (GPI) observations of AU Microscopii, a young M dwarf with an edge-on, dusty debris disk. Integral field spectroscopy and broadband imaging polarimetry were obtained during the commissioning of GPI. In our broadband imaging polarimetry observations, we detect the disk only in total intensity and find asymmetries in the morphology of the disk between the southeast and northwest sides. The southeast side of the disk exhibits a bump at 1$''$ (10 AU projected separation) that is three times more vertically extended and three times fainter in peak surface brightness than the northwest side at similar separations. This part of the disk is also vertically offset by 69$\pm$30 mas to the northeast at 1$''$ when compared to the established disk mid-plane and consistent with prior ALMA and Hubble Space Telescope/STIS observations. We see hints that the southeast bump might be a result of detecting a horizontal sliver feature above the main disk that could be the disk backside. Alternatively when including the morphology of the northwest side, where the disk mid-plane is offset in the opposite direction $\sim$50 mas between 0$.''$4 and 1$.''$2, the asymmetries suggest a warp-like feature. Using our integral field spectroscopy data to search for planets, we are 50% complete for $\sim$4 $M_\mathrm{Jup}$ planets at 4 AU. We detect a source, resolved only along the disk plane, that could either be a candidate planetary mass companion or a compact clump in the disk., 14 pages, 4 figures, accepted by ApJ Letters
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- 2015
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9. Polarimetry with the gemini planet imager: Methods, performance at first light, and the circumstellar ring around HR 4796A
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Marshall D. Perrin, Gaspard Duchene, Max Millar-Blanchaer, Michael P. Fitzgerald, James R. Graham, Sloane J. Wiktorowicz, Paul G. Kalas, Bruce Macintosh, Brian Bauman, Andrew Cardwell, Jeffrey Chilcote, Robert J. De Rosa, Daren Dillon, René Doyon, Jennifer Dunn, Darren Erikson, Donald Gavel, Stephen Goodsell, Markus Hartung, Pascale Hibon, Patrick Ingraham, Daniel Kerley, Quinn Konapacky, James E. Larkin, Jérôme Maire, Franck Marchis, Christian Marois, Tushar Mittal, Katie M. Morzinski, B. R. Oppenheimer, David W. Palmer, Jennifer Patience, Lisa Poyneer, Laurent Pueyo, Fredrik T. Rantakyrö, Naru Sadakuni, Leslie Saddlemyer, Dmitry Savransky, Rémi Soummer, Anand Sivaramakrishnan, Inseok Song, Sandrine Thomas, J. Kent Wallace, Jason J. Wang, Schuyler G. Wolff, Space Telescope Science Institute (STSci), Department of Astronomy [Berkeley], University of California [Berkeley], University of California-University of California, Department of Physics and Astronomy [UCLA, Los Angeles], University of California [Los Angeles] (UCLA), Department of Astronomy and Astrophysics [UCSC Santa Cruz], University of California [Santa Cruz] (UCSC), Department of Mathematics [Berkeley], Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), Stanford University, University of Notre Dame [Indiana] (UND), Departement de physique and Observatoire du Mont Megantic, Université de Montréal (UdeM), Gemini Observatory [Southern Operations Center], Association of Universities for Research in Astronomy (AURA), Large Synoptic Survey Telescope (LSST), University of California, University of California [San Diego] (UC San Diego), Carl Sagan Center, SETI Institute, University of Victoria [Canada] (UVIC), Department of Earth and Planetary Science [UC Berkeley] (EPS), Lawrence Livermore National Laboratory (LLNL), Arizona State University [Tempe] (ASU), European Southern Observatory (ESO), Department of Astronomy [Ithaca], Cornell University [New York], University of Georgia [USA], Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Caltech Department of Astronomy [Pasadena], California Institute of Technology (CALTECH), Leiden Observatory [Leiden], and Universiteit Leiden [Leiden]
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Point spread function ,Brightness ,010504 meteorology & atmospheric sciences ,Forward scatter ,Polarimetry ,FOS: Physical sciences ,Astrophysics ,adaptive optics [instrumentation] ,Astronomy & Astrophysics ,01 natural sciences ,Physical Chemistry ,circumstellar matter ,polarimeters [instrumentation] ,Atomic ,Particle and Plasma Physics ,Saturn ,0103 physical sciences ,Gemini Planet Imager ,Nuclear ,010303 astronomy & astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,ComputingMilieux_MISCELLANEOUS ,individual [stars] ,0105 earth and related environmental sciences ,Physics ,[PHYS]Physics [physics] ,Earth and Planetary Astrophysics (astro-ph.EP) ,polarization ,Molecular ,Astronomy and Astrophysics ,First light ,Space and Planetary Science ,astro-ph.EP ,Circumstellar dust ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Instrumentation and Methods for Astrophysics ,high angular resolution [instrumentation] ,Astronomical and Space Sciences ,Astrophysics - Earth and Planetary Astrophysics ,astro-ph.IM ,Physical Chemistry (incl. Structural) - Abstract
We present the first results from the polarimetry mode of the Gemini Planet Imager (GPI), which uses a new integral field polarimetry architecture to provide high contrast linear polarimetry with minimal systematic biases between the orthogonal polarizations. We describe the design, data reduction methods, and performance of polarimetry with GPI. Point spread function subtraction via differential polarimetry suppresses unpolarized starlight by a factor of over 100, and provides sensitivity to circumstellar dust reaching the photon noise limit for these observations. In the case of the circumstellar disk around HR 4796A, GPI's advanced adaptive optics system reveals the disk clearly even prior to PSF subtraction. In polarized light, the disk is seen all the way in to its semi-minor axis for the first time. The disk exhibits surprisingly strong asymmetry in polarized intensity, with the west side >9 times brighter than the east side despite the fact that the east side is slightly brighter in total intensity. Based on a synthesis of the total and polarized intensities, we now believe that the west side is closer to us, contrary to most prior interpretations. Forward scattering by relatively large silicate dust particles leads to the strong polarized intensity on the west side, and the ring must be slightly optically thick in order to explain the lower brightness in total intensity there. These findings suggest that the ring is geometrically narrow and dynamically cold, perhaps shepherded by larger bodies in the same manner as Saturn's F ring., 27 pages, 16 figures, submitted to the Astrophysical Journal. A version with full resolution figures is available at http://www.stsci.edu/~mperrin/papers/gpi_polarimetry_and_HR_4796A.pdf
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- 2015
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10. The first H-band spectrum of the giant planet β Pictoris b
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Inseok Song, Naru Sadakuni, Sloane J. Wiktorowicz, Brian J. Bauman, Mark S. Marley, Paul Kalas, Daren Dillon, Dmitry Savransky, Stephen J. Goodsell, Schuyler Wolff, Bruce Macintosh, Andrew Norton, B. R. Oppenheimer, Jennifer Dunn, Andrew Serio, James R. Graham, Pascale Hibon, J. Kent Wallace, Travis Barman, Markus Hartung, Christian Marois, Jennifer Patience, Donald T. Gavel, Jeffrey Chilcote, Michael P. Fitzgerald, Jérôme Maire, Robert J. De Rosa, Andrew Cardwell, Katie M. Morzinski, Laurent Pueyo, Patrick Ingraham, Quinn Konopacky, Adam Burrows, Rémi Soummer, Sandrine Thomas, Marshall D. Perrin, Franck Marchis, Max Millar-Blanchaer, David W. Palmer, Anand Sivaramakrishnan, Lisa Poyneer, Fredrik T. Rantakyrö, René Doyon, James E. Larkin, Leslie Saddlemyer, and Darren Erikson
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Physics ,Gas giant ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Effective temperature ,adaptive optics [instrumentation] ,Astronomy & Astrophysics ,Surface gravity ,Jupiter ,Stars ,13. Climate action ,Space and Planetary Science ,Beta Pictoris ,Astrophysics::Solar and Stellar Astrophysics ,Gemini Planet Imager ,spectroscopic [techniques] ,Astrophysics::Earth and Planetary Astrophysics ,Substellar object ,general [infrared] ,planetary systems ,Astrophysics::Galaxy Astrophysics ,individual [stars] ,Astronomical and Space Sciences - Abstract
© 2015. The American Astronomical Society. All rights reserved. Using the recently installed Gemini Planet Imager (GPI), we have obtained the first H-band spectrum of the planetary companion to the nearby young star β Pictoris. GPI is designed to image and provide low-resolution spectra of Jupiter-sized, self-luminous planetary companions around young nearby stars. These observations were taken covering the H band (1.65 μm). The spectrum has a resolving power of ∼45 and demonstrates the distinctive triangular shape of a cool substellar object with low surface gravity. Using atmospheric models, we find an effective temperature of 1600-1700K and a surface gravity of log(g) = 3.5-4.5 (cgs units). These values agree well with "hot-start" predictions from planetary evolution models for a gas giant with mass between 10 and 12 MJupand age between 10 and 20 Myr.
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- 2015
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11. Gemini planet imager spectroscopy of the HR 8799 planets c and d
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Stephen J. Goodsell, Schuyler Wolff, Daren Dillon, Didier Saumon, Rebecca Oppenheimer, Christian Marois, Lisa Poyneer, Bruce Macintosh, J. Kent Wallace, D. Gavel, Max Millar-Blanchaer, Marshall D. Perrin, Inseok Song, Patrick Ingraham, Jérôme Maire, Sloane J. Wiktorowicz, Fredrik T. Rantakyrö, Laurent Pueyo, Franck Marchis, James R. Graham, Dmitry Savransky, James A. Larkin, Sandrine Thomas, Quinn Konopacky, James McBride, Markus Hartung, Anand Sivaramakrishnan, René Doyon, Brian J. Bauman, Robert J. De Rosa, Naru Sadakuni, Paul Kalas, Katie M. Morzinski, Andrew Norton, Dave Palmer, Adam Burrows, Rémi Soummer, Jeffrey Chilcote, Travis Barman, Pascale Hibon, Michael P. Fitzgerald, Leslie Saddlemyer, Darren Erikson, Mark S. Marley, Jennifer Dunn, and Jennifer Patience
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Earth and Planetary Astrophysics (astro-ph.EP) ,gaseous planets [planets and satellites] ,Opacity ,Metallicity ,Astronomy ,FOS: Physical sciences ,Astronomy and Astrophysics ,adaptive optics [instrumentation] ,atmospheres [planets and satellites] ,Astronomy & Astrophysics ,imaging spectroscopy [techniques] ,Exoplanet ,Spectral line ,Space and Planetary Science ,Planet ,Gemini Planet Imager ,Astrophysics::Earth and Planetary Astrophysics ,Spectroscopy ,Variation (astronomy) ,planetary systems [infrared] ,high angular resolution [instrumentation] ,Astronomical and Space Sciences ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
During the first-light run of the Gemini Planet Imager (GPI) we obtained K-band spectra of exoplanets HR 8799 c and d. Analysis of the spectra indicates that planet d may be warmer than planet c. Comparisons to recent patchy cloud models and previously obtained observations over multiple wavelengths confirm that thick clouds combined with horizontal variation in the cloud cover generally reproduce the planets' spectral energy distributions. When combined with the 3 to 4 um photometric data points, the observations provide strong constraints on the atmospheric methane content for both planets. The data also provide further evidence that future modeling efforts must include cloud opacity, possibly including cloud holes, disequilibrium chemistry, and super-solar metallicity., Comment: Accepted for publication in ApJ
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- 2014
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12. On-sky low order non-common path correction of the GPI calibration unit
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Jennifer Dunn, Fredrik T. Rantakyrö, Paul Langlois, Donald T. Gavel, Stephen J. Goodsell, James K. Wallace, Lisa Poyneer, Sandrine Thomas, Markus Hartung, Daren Dillon, Pascale Hibon, Bruce Macintosh, Dave Palmer, Dmitry Savransky, and Naru Sadakuni
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High contrast imaging ,Wavefronts ,FOS: Physical sciences ,Commissioning phase ,law.invention ,Telescope ,Optics ,law ,Jet Propulsion Laboratory ,Atmospheric corrections ,Gemini Planet Imager ,Adaptive optics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Coronagraph ,Common path ,Focusing ,Physics ,Wavefront ,business.industry ,Wavefront correction ,Wave front sensors ,First light ,Wavefront sensor ,Interferometry ,Extreme adaptive optics ,Calibration ,business ,Astrophysics - Instrumentation and Methods for Astrophysics ,Telescopes - Abstract
The Gemini Planet Imager (GPI) entered on-sky commissioning phase, and had its First Light at the Gemini South telescope in November 2013. Meanwhile, the fast loops for atmospheric correction of the Extreme Adaptive Optics (XAO) system have been closed on many dozen stars at different magnitudes (I=4-8), elevation angles and a variety of seeing conditions, and a stable loop performance was achieved from the beginning. Ultimate contrast performance requires a very low residual wavefront error (design goal 60 nm RMS), and optimization of the planet finding instrument on different ends has just begun to deepen and widen its dark hole region. Laboratory raw contrast benchmarks are in the order of 10-6 or smaller. In the telescope environment and in standard operations new challenges are faced (changing gravity, temperature, vibrations) that are tackled by a variety of techniques such as Kalman filtering, open-loop models to keep alignment to within 5 mas, speckle nulling, and a calibration unit (CAL). The CAL unit was especially designed by the Jet Propulsion Laboratory to control slowly varying wavefront errors at the focal plane of the apodized Lyot coronagraph by the means of two wavefront sensors: 1) a 7x7 low order Shack-Hartmann SH wavefront sensor (LOWFS), and 2) a special Mach-Zehnder interferometer for mid-order spatial frequencies (HOWFS) - atypical in that the beam is split in the focal plane via a pinhole but recombined in the pupil plane with a beamsplitter. The original design goal aimed for sensing and correcting on a level of a few nm which is extremely challenging in a telescope environment. This paper focuses on non-common path low order wavefront correction as achieved through the CAL unit on sky. We will present the obtained results as well as explain challenges that we are facing., Adaptive Optics Systems IV, June 22-27, 2014, Series: Proceedings of SPIE; no. 9148
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- 2014
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13. The Gemini planet imager: first light and commissioning
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Lisa Poyneer, Vlad Reshetov, Laurent Pueyo, Michael P. Fitzgerald, Jérôme Maire, Brian J. Bauman, Kathleen Labrie, John Pazder, Markus Hartung, Rebecca Oppenheimer, Jason J. Wang, Franck Marchis, Jeffery Chilcote, Donald T. Gavel, Andrew Cardwell, Robert J. De Rosa, Carlos Quiroz, Patrick Ingraham, Sandrine Thomas, Naru Sadakuni, James E. Larkin, Kris Caputa, Ramon Galvez, David Palmer, Malcolm Smith, Bruce Macintosh, Dmitry Savransky, Sloane Wiktorowicz, Alexandra Z. Greenbaum, Marshall D. Perrin, René Doyon, Darren Erickson, Andre Anthony, Daren Dillon, Quinn Konopacky, Les Saddlemyer, Rémi Soummer, James R. Graham, Max Millar-Blanchaer, Andrew Serio, Christian Marois, James K. Wallace, Jenny Atwood, Arturo Nunez, Anand Sivaramakrishnan, Stephen J. Goodsell, Schuyler Wolff, Jason Weiss, Dan Kerley, Fredrik T. Rantakyrö, Katie M. Morzinski, Pascale Hibon, and Jennifer Dunn
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Physics ,business.industry ,Astronomy ,Wavefront sensor ,First light ,Exoplanet ,law.invention ,Telescope ,Optics ,Integral field spectrograph ,law ,Gemini Planet Imager ,business ,Adaptive optics ,Coronagraph - Abstract
The Gemini Planet Imager (GPI) is a facility extreme-AO high-contrast instrument – optimized solely for study of faint companions – on the Gemini telescope. It combines a high-order MEMS AO system (1493 active actuators), an apodized pupil Lyot coronagraph, a high-accuracy IR post-coronagraph wavefront sensor, and a near-infrared integral field spectrograph. GPI incorporates several other novel features such as ultra-high quality optics, a spatially-filtered wavefront sensor, and new calibration techniques. GPI had first light in November 2013. This paper presnets results of first-light and performance verification and optimization and shows early science results including extrasolar planet spectra and polarimetric detection of the HR4696A disk. GPI is now achieving contrasts approaching 10-6 at 0.5” in 30 minute exposures.
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14. On-sky performance during verification and commissioning of the Gemini Planet Imager's adaptive optics system
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Brian J. Bauman, Jeffrey Chilcote, Bruce Macintosh, Stephen J. Goodsell, D. Gavel, Markus Hartung, Jean-Pierre Véran, Dmitry Savransky, Marshall D. Perrin, Robert J. De Rosa, Lisa Poyneer, David Palmer, Pascale Hibon, Naru Sadakuni, Fredrik T. Rantakyrö, Andrew Cardwell, Sandrine Thomas, and Daren Dillon
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Wavefront ,Spatial filter ,business.industry ,Computer science ,Wavefronts ,Wave front reconstruction ,Wave front sensors ,FOS: Physical sciences ,Kalman filter ,Wavefront sensor ,Linear-quadratic-Gaussian control ,Gemini Planet Imager ,Control theory ,Modal gain ,LQG control ,business ,Adaptive optics ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Computer hardware - Abstract
The Gemini Planet Imager instrument's adaptive optics (AO) subsystem was designed specifically to facilitate high-contrast imaging. It features several new technologies, including computationally efficient wavefront reconstruction with the Fourier transform, modal gain optimization every 8 seconds, and the spatially filtered wavefront sensor. It also uses a Linear-Quadratic-Gaussian (LQG) controller (aka Kalman filter) for both pointing and focus. We present on-sky performance results from verification and commissioning runs from December 2013 through May 2014. The efficient reconstruction and modal gain optimization are working as designed. The LQG controllers effectively notch out vibrations. The spatial filter can remove aliases, but we typically use it oversized by about 60% due to stability problems., Adaptive Optics Systems IV, June 22-27, 2014, Series: Proceedings of SPIE; no. 9148
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- 2014
15. Automated alignment and on-sky performance of the Gemini planet imager coronagraph
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Markus Hartung, Bruce Macintosh, Daren Dillon, Pascale Hibon, Stephen J. Goodsell, Andrew Cardwell, Sandrine Thomas, Lisa Poyneer, Andrew Serio, Jennifer Dunn, Fredrik T. Rantakyrö, Dmitry Savransky, and Naru Sadakuni
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high contrast imaging ,Computer science ,media_common.quotation_subject ,FOS: Physical sciences ,law.invention ,adaptive optics ,Optics ,Integral field spectrograph ,Observatory ,law ,Planet ,extrasolar planets ,Gemini Planet Imager ,Adaptive optics ,automated operations ,Coronagraph ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,media_common ,Earth and Planetary Astrophysics (astro-ph.EP) ,business.industry ,Cassegrain reflector ,alignment ,Exoplanet ,astronomy ,GPI ,Sky ,business ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The Gemini Planet Imager (GPI) is a next-generation, facility instrument currently being commissioned at the Gemini South observatory. GPI combines an extreme adaptive optics system and integral field spectrograph (IFS) with an apodized-pupil Lyot coronagraph (APLC) producing an unprecedented capability for directly imaging and spectroscopically characterizing extrasolar planets. GPI's operating goal of 10-7 contrast requires very precise alignments between the various elements of the coronagraph (two pupil masks and one focal plane mask) and active control of the beam path throughout the instrument. Here, we describe the techniques used to automatically align GPI and maintain the alignment throughout the course of science observations. We discuss the particular challenges of maintaining precision alignments on a Cassegrain mounted instrument and strategies that we have developed that allow GPI to achieve high contrast even in poor seeing conditions., Ground-Based and Airborne Instrumentation for Astronomy V, June 22-26, 2014, Series: Proceedings of SPIE; no. 9147
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- 2014
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16. The Integral Field Spectrograph for the Gemini Planet Imager
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Ian S. McLean, Carlos Quiroz, Bruce Macintosh, Brian J. Bauman, James E. Larkin, Quinn Konopacky, Jérôme Maire, James R. Graham, Chris Johnson, Daren Dillon, Markus Hartung, Simon Thibault, George Brims, Marshall D. Perrin, John Canfield, Evan Kress, Naru Sadakuni, Pascale Hibon, Leslie Saddlemyer, David Palmer, Philippe Vallée, Jennifer Dunn, Andrew Cardwell, Michael P. Fitzgerald, Sandrine Thomas, René Doyon, Theodore Aliado, Andrew Serio, Fredrik T. Rantakyrö, Jeffrey Chilcote, Kenneth G. Magnone, Patrick Ingraham, Stephen J. Goodsell, and Jason Weiss
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Wavefronts ,Astronomy ,FOS: Physical sciences ,Physics::Optics ,Chromatic aberration ,Optics ,Integral field spectrograph ,Speckle ,Spectrographs ,Optical systems ,Gemini Planet Imager ,Dual-polarizations ,Spectral resolution ,Adaptive optics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Spectrograph ,Astrophysics::Galaxy Astrophysics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Wavefront ,Physics ,business.industry ,Speckle suppression ,Astrophysics::Instrumentation and Methods for Astrophysics ,Prisms ,Wollaston prism ,Diffraction limited ,Extrasolar planets ,Aberrations ,Wavelength ranges ,Prism ,Astrophysics::Earth and Planetary Astrophysics ,Complex optical systems ,business ,Astrophysics - Instrumentation and Methods for Astrophysics ,RMS wavefront error ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The Gemini Planet Imager (GPI) is a complex optical system designed to directly detect the self-emission of young planets within two arcseconds of their host stars. After suppressing the starlight with an advanced AO system and apodized coronagraph, the dominant residual contamination in the focal plane are speckles from the atmosphere and optical surfaces. Since speckles are diffractive in nature their positions in the field are strongly wavelength dependent, while an actual companion planet will remain at fixed separation. By comparing multiple images at different wavelengths taken simultaneously, we can freeze the speckle pattern and extract the planet light adding an order of magnitude of contrast. To achieve a bandpass of 20%, sufficient to perform speckle suppression, and to observe the entire two arcsecond field of view at diffraction limited sampling, we designed and built an integral field spectrograph with extremely low wavefront error and almost no chromatic aberration. The spectrograph is fully cryogenic and operates in the wavelength range 1 to 2.4 microns with five selectable filters. A prism is used to produce a spectral resolution of 45 in the primary detection band and maintain high throughput. Based on the OSIRIS spectrograph at Keck, we selected to use a lenslet-based spectrograph to achieve an rms wavefront error of approximately 25 nm. Over 36,000 spectra are taken simultaneously and reassembled into image cubes that have roughly 192x192 spatial elements and contain between 11 and 20 spectral channels. The primary dispersion prism can be replaced with a Wollaston prism for dual polarization measurements. The spectrograph also has a pupil-viewing mode for alignment and calibration., Ground-Based and Airborne Instrumentation for Astronomy V, June 22-26, 2014, Series: Proceedings of SPIE; no. 9147
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- 2014
17. Gemini Planet Imager Observational Calibrations V: Astrometry and Distortion
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Leslie Saddlemyer, James R. Graham, Katie M. Morzinski, Paul Kalas, Ben R. Oppenheimer, Jeffrey Chilcote, Jason J. Wang, Marshall D. Perrin, James E. Larkin, Daniel C. Fabrycky, Laurent Pueyo, Jérôme Maire, Patrick Ingraham, Sasha Hinkley, Michael P. Fitzgerald, Franck Marchis, Sandrine Thomas, Christian Marois, Anand Sivaramakrishnan, Jennifer Patience, Stephen J. Goodsell, Thomas M. Esposito, Bruce Macintosh, Quinn Konopacky, Robert J. De Rosa, Naru Sadakuni, Daren Dillon, Ramsay, Suzanne K., McLean, Ian S., and Takami, Hideki
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High contrast imaging ,Astronomy ,FOS: Physical sciences ,Field of view ,Astrophysics ,Pixels ,Integral Field Spectroscopy ,Integral field spectrograph ,Spectrographs ,Distortion ,Gemini Planet Imager ,Adaptive optics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Pixel ,Astrophysics::Instrumentation and Methods for Astrophysics ,Monte Carlo methods ,Astrometry ,Exoplanet ,GPI ,Calibration ,astrometry ,Astrophysics::Earth and Planetary Astrophysics ,Distortion (waves) ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We present the results of both laboratory and on sky astrometric characterization of the Gemini Planet Imager (GPI). This characterization includes measurement of the pixel scale∗ of the integral field spectrograph (IFS), the position of the detector with respect to north, and optical distortion. Two of these three quantities (pixel scale and distortion) were measured in the laboratory using two transparent grids of spots, one with a square pattern and the other with a random pattern. The pixel scale in the laboratory was also estimate using small movements of the artificial star unit (ASU) in the GPI adaptive optics system. On sky, the pixel scale and the north angle are determined using a number of known binary or multiple systems and Solar System objects, a subsample of which had concurrent measurements at Keck Observatory. Our current estimate of the GPI pixel scale is 14.14 ± 0.01 millarcseconds/pixel, and the north angle is -1.00 ± 0.03°. Distortion is shown to be small, with an average positional residual of 0.26 pixels over the field of view, and is corrected using a 5th order polynomial. We also present results from Monte Carlo simulations of the GPI Exoplanet Survey (GPIES) assuming GPI achieves ∼1 milliarcsecond relative astrometric precision. We find that with this precision, we will be able to constrain the eccentricities of all detected planets, and possibly determine the underlying eccentricity distribution of widely separated Jovians., Ground-Based and Airborne Instrumentation for Astronomy V, June 22-26, 2014, Series: Proceedings of SPIE; no. 9147
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- 2014
18. Gemini Planet Imager Observational Calibrations VII: On-Sky Polarimetric Performance of the Gemini Planet Imager
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Dmitry Savransky, Andrew Cardwell, Sloane Wiktorowicz, Marshall D. Perrin, Inseok Song, Sandrine Thomas, Stephen J. Goodsell, Jeffrey Chilcote, Bruce Macintosh, Zachary H. Draper, James R. Graham, Patrick Ingraham, Jérôme Maire, Fredrik T. Rantakyrö, Naru Sadakuni, Pascale Hibon, Max Millar-Blanchaer, Markus Hartung, and Michael P. Fitzgerald
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010504 meteorology & atmospheric sciences ,media_common.quotation_subject ,Polarimetry ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,law.invention ,Telescope ,law ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Gemini Planet Imager ,010303 astronomy & astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,media_common ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Linear polarization ,Astrophysics::Instrumentation and Methods for Astrophysics ,Polarization (waves) ,Exoplanet ,Stars ,13. Climate action ,Sky ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We present on-sky polarimetric observations with the Gemini Planet Imager (GPI) obtained at straight Cassegrain focus on the Gemini South 8-m telescope. Observations of polarimetric calibrator stars, ranging from nearly unpolarized to strongly polarized, enable determination of the combined telescope and instrumental polarization. We find the conversion of Stokes $I$ to linear and circular instrumental polarization in the instrument frame to be $I \rightarrow (Q_{\rm IP}, U_{\rm IP}, P_{\rm IP}, V_{\rm IP}) = (-0.037 \pm 0.010\%, +0.4338 \pm 0.0075\%, 0.4354 \pm 0.0075\%, -6.64 \pm 0.56\%)$. Such precise measurement of instrumental polarization enables $\sim 0.1\%$ absolute accuracy in measurements of linear polarization, which together with GPI's high contrast will allow GPI to explore scattered light from circumstellar disk in unprecedented detail, conduct observations of a range of other astronomical bodies, and potentially even study polarized thermal emission from young exoplanets. Observations of unpolarized standard stars also let us quantify how well GPI's differential polarimetry mode can suppress the stellar PSF halo. We show that GPI polarimetry achieves cancellation of unpolarized starlight by factors of 100-200, reaching the photon noise limit for sensitivity to circumstellar scattered light for all but the smallest separations at which the calibration for instrumental polarization currently sets the limit., Comment: 11 pages, 3 figures. Proceedings of the SPIE, 9147-305
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19. Gemini Planet Imager Observational Calibrations I: Overview of the GPI Data Reduction Pipeline
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Markus Hartung, Jean-Baptiste Ruffio, Patrick Ingraham, Christian Marois, James R. Graham, David Lafrenière, Mathilde Beaulieu, David Palmer, Naru Sadakuni, Fredrik T. Rantakyrö, Michael P. Fitzgerald, Abhijith Rajan, Jason J. Wang, Sandrine Thomas, Jeffrey Chilcote, Pascale Hibon, Anand Sivaramakrishnan, James E. Larkin, Alexandra Z. Greenbaum, Laurent Pueyo, Max Millar-Blanchaer, Jennifer Patience, Marshall D. Perrin, Stephen J. Goodsell, Schuyler Wolff, Robert J. De Rosa, Jean-François Lavigne, Dmitry Savransky, Zachary H. Draper, Kimberly Ward-Duong, Rémi Soummer, Franck Marchis, Jérôme Maire, Sloane J. Wiktorowicz, Bruce Macintosh, Quinn Konopacky, Kathleen Labrie, René Doyon, Space Telescope Science Institute (STScI), Dunlap Institute for Astronomy and Astrophysics, Univ. of Toronto (Canada), Kavli Institute for Particle Astrophysics and Cosmology, Stanford Univ. (United States), Center for Radiophysics and Space Research, Cornell University (CRSR), Department of Physics and Astronomy, University of Toronto, Johns Hopkins University (JHU), SETI Institute (United States), Univ. of California, Berkeley (United States), Department of Physics and Astronomy, University of Victoria, Gemini Observatory, Southern Operations Center, National Research Council of Canada (NRC), Arizona State University, University of California, Los Angeles (UCLA), Univ. de Montreal (Canada), Lawrence Livermore National Laboratory (LLNL), Gemini Observatory, Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA), ABB, Inc. (Canada), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), NASA Ames Research Center (ARC), and University of California, Santa Cruz (UCSC)
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High contrast imaging ,010504 meteorology & atmospheric sciences ,Infrared ,Computer science ,Pipeline (computing) ,Astronomy ,Polarimetry ,FOS: Physical sciences ,01 natural sciences ,Integral Field Spectroscopy ,Integral field spectrograph ,Software ,Spectrographs ,Computer graphics (images) ,Scientific analysis ,0103 physical sciences ,Gemini Planet Imager ,010303 astronomy & astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,0105 earth and related environmental sciences ,Pipelines ,Earth and Planetary Astrophysics (astro-ph.EP) ,Data reduction ,business.industry ,Reduction systems ,Open source software ,Data handling ,Exoplanet ,Polarization modes ,Extrasolar planets ,Calibration ,Exo-planets ,business ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Instrumentation and Methods for Astrophysics ,Polarimeters ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The Gemini Planet Imager (GPI) has as its science instrument an infrared integral field spectrograph/polarimeter (IFS). Integral field spectrographs are scientificially powerful but require sophisticated data reduction systems. For GPI to achieve its scientific goals of exoplanet and disk characterization, IFS data must be reconstructed into high quality astrometrically and photometrically accurate datacubes in both spectral and polarization modes, via flexible software that is usable by the broad Gemini community. The data reduction pipeline developed by the GPI instrument team to meet these needs is now publicly available following GPI's commissioning. This paper, the first of a series, provides a broad overview of GPI data reduction, summarizes key steps, and presents the overall software framework and implementation. Subsequent papers describe in more detail the algorithms necessary for calibrating GPI data. The GPI data reduction pipeline is open source, available from planetimager.org, and will continue to be enhanced throughout the life of the instrument. It implements an extensive suite of task primitives that can be assembled into reduction recipes to produce calibrated datasets ready for scientific analysis. Angular, spectral, and polarimetric differential imaging are supported. Graphical tools automate the production and editing of recipes, an integrated calibration database manages reference files, and an interactive data viewer customized for high contrast imaging allows for exploration and manipulation of data., Ground-Based and Airborne Instrumentation for Astronomy V, June 22-26, 2014, Series: Proceedings of SPIE; no. 9147
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- 2014
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20. On-sky vibration environment for the Gemini Planet Imager and mitigation effort
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Gaston Gausachs, Pascale Hibon, Ramon Galvez, Andrew Cardwell, Daren Dillon, Markus Hartung, Les Saddlemyer, Lisa Poyneer, Andrés Guesalaga, Stephen J. Goodsell, Andrew Serio, Chas Cavedoni, Kent Wallace, Myung Cho, Fredrik T. Rantakyrö, Naru Sadakuni, James E. Larkin, Jeffrey Chilcote, Dmitry Savransky, Paul Collins, Bruce Macintosh, Dave Palmer, and Thomas L. Hayward
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High contrast imaging ,FOS: Physical sciences ,Specific frequencies ,law.invention ,Telescope ,Vibration absorber ,law ,Gemini Planet Imager ,Adaptive optics ,Coronagraph ,LQG ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Remote sensing ,Wavefront ,Physics ,Instrument Data ,Vibration environment ,Telescope structures ,Exoplanet ,Tilt (optics) ,Extreme adaptive optics ,Integral field spectrograph ,Astrophysics - Instrumentation and Methods for Astrophysics ,Kalman filters ,Telescopes - Abstract
The Gemini Planet Imager (GPI) entered on-sky commissioning and had its first-light at the Gemini South (GS) telescope in November 2013. GPI is an extreme adaptive optics (XAO), high-contrast imager and integral-field spectrograph dedicated to the direct detection of hot exo-planets down to a Jupiter mass. The performance of the apodized pupil Lyot coronagraph depends critically upon the residual wavefront error (design goal of 60nmRMS with, Adaptive Optics Systems IV, June 22-27, 2014, Series: Proceedings of SPIE; no. 9148
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- 2014
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21. Gemini Planet imager Observational Calibrations X: Non-Redundant Masking on GPI
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Patrick Ingraham, Andrew Serio, Stephen J. Goodsell, Schuyler Wolff, Markus Hartung, Alexandra Z. Greenbaum, M. D. Perrin, Lisa Poyneer, Anthony Cheetham, Naru Sadakuni, Anand Sivaramakrishnan, Peter Tuthill, Laurent Pueyo, B. Norris, Andrew Cardwell, Fredrik T. Rantakyrö, Dmitry Savransky, Sandrine Thomas, Pascale Hibon, and Bruce Macintosh
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Wavefront ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Pixel ,business.industry ,FOS: Physical sciences ,01 natural sciences ,law.invention ,010309 optics ,Interferometry ,Optics ,law ,0103 physical sciences ,Calibration ,Gemini Planet Imager ,Astrophysics - Instrumentation and Methods for Astrophysics ,business ,Adaptive optics ,010303 astronomy & astrophysics ,Coronagraph ,Spectrograph ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The Gemini Planet Imager (GPI) Extreme Adaptive Optics Coronograph contains an interferometric mode: a 10-hole non-redundant mask (NRM) in its pupil wheel. GPI operates at $Y, J, H$, and $K$ bands, using an integral field unit spectrograph (IFS) to obtain spectral data at every image pixel. NRM on GPI is capable of imaging with a half resolution element inner working angle at moderate contrast, probing the region behind the coronagraphic spot. The fine features of the NRM PSF can provide a reliable check on the plate scale, while also acting as an attenuator for spectral standard calibrators that would otherwise saturate the full pupil. NRM commissioning data provides details about wavefront error in the optics as well as operations of adaptive optics control without pointing control from the calibration system. We compare lab and on-sky results to evaluate systematic instrument properties and examine the stability data in consecutive exposures. We discuss early on-sky performance, comparing images from integration and tests with the first on-sky images, and demonstrate resolving a known binary. We discuss the status of NRM and implications for future science with this mode., Comment: 14 pages, 14 figures. Proceedings of the SPIE, 9147-135
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- 2014
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22. Characterization of the Atmospheric Dispersion Corrector of the Gemini Planet Imager
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Ramon Galvez, Vincent Fesquet, Markus Hartung, Andrew Cardwell, Jennifer Atwood, Les Saddlemyer, Bruce Macintosh, Sandrine Thomas, Dan Kerley, Marshall D. Perrin, Jennifer Dunn, Kayla Hardie, Pascale Hibon, Stephen J. Goodsell, Fredrik T. Rantakyrö, Andrew Serio, James R. Graham, Carlos Quiroz, Dmitry Savransky, Gaston Gausachs, and Naru Sadakuni
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Earth and Planetary Astrophysics (astro-ph.EP) ,media_common.quotation_subject ,Instrumentation ,FOS: Physical sciences ,First light ,Atmospheric dispersion modeling ,law.invention ,Telescope ,Sky ,law ,Dispersion (optics) ,Environmental science ,Gemini Planet Imager ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Zenith ,Astrophysics - Earth and Planetary Astrophysics ,Remote sensing ,media_common - Abstract
An Atmospheric Dispersion Corrector (ADC) uses a double-prism arrangement to nullify the vertical chromatic dispersion introduced by the atmosphere at non-zero zenith distances. The ADC installed in the Gemini Planet Imager (GPI) was first tested in August 2012 while the instrument was in the laboratory. GPI was installed at the Gemini South telescope in August 2013 and first light occurred later that year on November 11th. In this paper, we give an overview of the characterizations and performance of this ADC unit obtained in the laboratory and on sky, as well as the structure of its control software., Comment: 16 pages, 12 figures. Proceedings of the SPIE, 9147-183
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- 2014
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23. First light of the Gemini Planet Imager
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Inseok Song, Dmitry Savransky, Sloane Wiktorowicz, Marshall D. Perrin, Stephen J. Goodsell, Schuyler Wolff, Adam Burrows, Ben R. Oppenheimer, Rémi Soummer, Donald T. Gavel, Darren Erikson, Andrew Cardwell, Lisa Poyneer, J. Kent Wallace, Christian Marois, David Palmer, Andrew Norton, Bruce Macintosh, Jeffrey Chilcote, James E. Larkin, Katie M. Morzinski, Naru Sadakuni, Franck Marchis, Andrew Serio, Daren Dillon, Max Millar-Blanchaer, Quinn Konopacky, Robert J. De Rosa, Sandrine Thomas, Jennifer Dunn, James McBride, Patrick Ingraham, René Doyon, Laurent Pueyo, James R. Graham, Pascale Hibon, Anand Sivaramakrishnan, Jennifer Patience, Fredrik T. Rantakyrö, Travis Barman, Michael P. Fitzgerald, Brian J. Bauman, Paul Kalas, Leslie Saddlemyer, Markus Hartung, Jérôme Maire, Mark S. Marley, Lawrence Livermore National Laboratory (LLNL), Astronomy Department, University of California, Berkeley, CA 94720, Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305, Dunlap Institute for Astronomy and Astrophysics, University of Toronto, National Research Council of Canada Herzberg, Victoria, BC, Canada V9E 2E7, Space Telescope Science Institute (STScI), Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, Department of Astrophysical Sciences, Princeton University, Gemini Observatory, Department of Physics and Astronomy, University of California, School of Earth and Space Exploration, Arizona State University, P.O. Box 871404, Tempe, Lick Observatory, University of California, Departement of Physics, McGill University, SETI Institute, Carl Sagan Center, Mountain View, CA 94043, Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), MS 245-3, NASA Ames Research Center, Steward Observatory, University of Arizona, American Museum of Natural History, Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853, Department of Physics, Tbilisi State University, Jet Propulsion Laboratory, California Institute of Technology (JPL), and Department of Physics and Astronomy, Johns Hopkins University
- Subjects
debris disks ,interferometer ,brightness ,diffraction ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,telescope ,satellite imagery ,law.invention ,Fourier transformation ,sensor ,law ,Planet ,gemini planet imager ,Astrophysics::Solar and Stellar Astrophysics ,Beta Pictoris ,Gemini Planet Imager ,Spectral resolution ,Coronagraph ,Astrophysics::Galaxy Astrophysics ,polarimetry ,Physics ,Multidisciplinary ,Exoplanets Special Feature ,extreme adaptive optics ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astrometry ,imaging system ,Position angle ,optics ,Exoplanet ,gravity ,infrared wavefront sensor ,high-contrast imaging ,Astrophysics::Earth and Planetary Astrophysics ,light ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
International audience; The Gemini Planet Imager is a dedicated facility for directly imaging and spectroscopically characterizing extrasolar planets. It combines a very high-order adaptive optics system, a diffraction-suppressing coronagraph, and an integral field spectrograph with low spectral resolution but high spatial resolution. Every aspect of the Gemini Planet Imager has been tuned for maximum sensitivity to faint planets near bright stars. During first-light observations, we achieved an estimated H band Strehl ratio of 0.89 and a 5-sigma contrast of 106 at 0.75 arcseconds and 105 at 0.35 arcseconds. Observations of Beta Pictoris clearly detect the planet, Beta Pictoris b, in a single 60-s exposure with minimal postprocessing. Beta Pictoris b is observed at a separation of 434 ± 6 milliarcseconds (mas) and position angle 211.8 ± 0.5°. Fitting the Keplerian orbit of Beta Pic b using the new position together with previous astrometry gives a factor of 3 improvement in most parameters over previous solutions. The planet orbits at a semimajor axis of 9.0-0.4 0.8 AU near the 3:2 resonance with the previously known 6-AU asteroidal belt and is aligned with the inner warped disk. The observations give a 4% probability of a transit of the planet in late 2017.
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- 2014
- Full Text
- View/download PDF
24. Gemini Planet Imager Observational Calibrations VIII: Characterization and Role of Satellite Spots
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Dmitry Savransky, Stephen J. Goodsell, Jason J. Wang, Joanna Bulger, Abhijith Rajan, Robert J. De Rosa, Marshall D. Perrin, Christian Marois, Ben R. Oppenheimer, Patrick Ingraham, Fredrik T. Rantakyrö, Kimberly Ward-Duong, Anand Sivaramakrishnan, James R. Graham, Jennifer Patience, Alexandra Z. Greenbaum, Laurent Pueyo, Naru Sadakuni, Pascale Hibon, Paul Kalas, Andrew Cardwell, and Sandrine Thomas
- Subjects
Infrared devices ,High contrast imaging ,Brightness ,Satellites ,Astronomy ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,law.invention ,Integral field spectrograph ,law ,Planet ,Astrophysics::Solar and Stellar Astrophysics ,Gemini Planet Imager ,Coronagraph ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Astrophysics::Galaxy Astrophysics ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Signal to noise ratio ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astrometry ,Stars ,Exoplanet ,Extrasolar planets ,GPI ,Spectrophotometry ,astrometry ,Exo-planets ,Satellite ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,Adaptive optics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The Gemini Planet Imager (GPI) combines extreme adaptive optics, an integral field spectrograph, and a high performance coronagraph to directly image extrasolar planets in the near-infrared. Because the coronagraph blocks most of the light from the star, it prevents the properties of the host star from being measured directly. Instead, satellite spots, which are created by diffraction from a square grid in the pupil plane, can be used to locate the star and extract its spectrum. We describe the techniques implemented into the GPI Data Reduction Pipeline to measure the properties of the satellite spots and discuss the precision of the reconstructed astrometry and spectrophotometry of the occulted star. We find the astrometric precision of the satellite spots in an H-band datacube to be 0.05 pixels and is best when individual satellite spots have a signal to noise ratio (SNR) of > 20. In regards to satellite spot spectrophotometry, we find that the total flux from the satellite spots is stable to ∼7% and scales linearly with central star brightness and that the shape of the satellite spot spectrum varies on the 2% level., Ground-Based and Airborne Instrumentation for Astronomy V, June 22-26, 2014, Series: Proceedings of SPIE; no. 9147
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- 2014
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25. The Gemini Planet Imager: integration and status
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F. Rantakyrö, Dan Kerley, Ramon Galvez, Lisa Poyneer, Stephen J. Goodsell, René Doyon, David Palmer, James R. Graham, Jeffery Chilcote, Sandrine Thomas, Jason Weiss, Brian J. Bauman, Andre Anthony, Marshall D. Perrin, Kris Caputa, James E. Larkin, Carlos Quirez, Markus Hartung, J. Kent Wallace, Donald T. Gavel, Leslie Saddlemyer, Kathleen Labrie, Arturo Nunez, Nicolas A. Barriga, Jérôme Maire, John Pazder, Sloane J. Wiktorowicz, Vlad Reshtov, Bruce Macintosh, Jennifer Atwood, Malcolm Smith, J. A. Isaacs, Daren Dillon, Anand Sivaramakrishnan, Quinn Konopacky, Rémi Soummer, Ben R. Oppenheimer, Christian Marois, Max Millar-Blanchaer, Dmitry Savransky, Jennifer Dunn, and Naru Sadakuni
- Subjects
Physics ,business.industry ,Wavefront sensor ,Exoplanet ,law.invention ,Interferometry ,Speckle pattern ,Optics ,Integral field spectrograph ,law ,Gemini Planet Imager ,business ,Adaptive optics ,Coronagraph - Abstract
The Gemini Planet Imager is a next-generation instrument for the direct detection and characterization of young warm exoplanets, designed to be an order of magnitude more sensitive than existing facilities. It combines a 1700-actuator adaptive optics system, an apodized-pupil Lyot coronagraph, a precision interferometric infrared wavefront sensor, and a integral field spectrograph. All hardware and software subsystems are now complete and undergoing integration and test at UC Santa Cruz. We will present test results on each subsystem and the results of end-to-end testing. In laboratory testing, GPI has achieved a raw contrast (without post-processing) of 10-6 5σ at 0.4”, and with multiwavelength speckle suppression, 2x10-7 at the same separation.
- Published
- 2012
- Full Text
- View/download PDF
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