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GPI Data Pipeline Downloads

The GPI data pipeline allows users to reduce and calibrate raw GPI data into spectral and polarimetric datacubes, and apply various PSF subtraction methods to those data.

It is written in IDL by members of the GPI instrument collaboration. Source code is available for users who have copies of IDL, and a compiled version is available for all others.

Users of the GPI data pipeline should please cite one of the following papers:

Perrin, Maire, Ingraham,  et al. “Gemini Planet Imager Observational Calibrations I: Overview of the GPI Data Reduction Pipeline”  Proc. SPIE, 2014, 9147

Maire, Perrin, Doyon, et al. “Test Results for the Gemini Planet Imager Data Pipeline”, Proc. SPIE, 2012, 8451

Maire, Perrin, Doyon, et al. “Data Reduction Pipeline for the Gemini Planet Imager”, Proc SPIE, 2010, 7735

Downloads

GPI Data pipeline version 1.4.0 (released 2016 July 15). ZIP files:

Documentation

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Exiled exoplanet likely kicked out of star’s neighborhood

Exiled exoplanet likely kicked out of star’s neighborhood

UC Berkeley Press Release published on December 1, 2015
Written by Robert Sander, Media Relations

A planet discovered last year sitting at an unusually large distance from its star – 16 times farther than Pluto is from the sun – may have been kicked out of its birthplace close to the star in a process similar to what may have happened early in our own solar system’s history.

Images from the Gemini Planet Imager (GPI) in the Chilean Andes and the Hubble Space Telescope show that the star has a lopsided comet belt indicative of a very disturbed solar system, and hinting that the planet interactions that roiled the comets closer to the star might have sent the exoplanet into exile as well.

A wide-angle view of the star HD 106906 taken by the Hubble Space Telescope and a close-up view from the Gemini Planet Imager reveal a dynamically disturbed system of comets, suggesting a link between this and the unusually distant planet (upper right), 11 times the mass of Jupiter. Click image for hi-res versions & caption. Paul Kalas image, UC Berkeley.

A wide-angle view of the star HD 106906 taken by the Hubble Space Telescope and a close-up view from the Gemini Planet Imager reveal a dynamically disturbed system of comets, suggesting a link between this and the unusually distant planet (upper right), 11 times the mass of Jupiter. Click image for hi-res versions & caption. Paul Kalas image, UC Berkeley.

The planet may even have its own ring of debris that it dragged along with it.

“We think that the planet itself could have captured material from the comet belt, and that the planet is surrounded by a large dust ring or dust shroud,” said Paul Kalas, an adjunct professor of astronomy at the University of California, Berkeley. “We conducted three tests and found tentative evidence for a dust cloud, but the jury is still out.”

“The measurements we made on the planet suggest it may be dustier than comparison objects, and we are making follow-up observations to check if the planet is really encircled by a disk – an exciting possibility,” added Abhi Rajan, a graduate student at Arizona State University who analyzed the planet images.

Such planets are of interest because in its youth, our own solar system may have had planets that were kicked out of the local neighborhood and are no longer among of the eight planets we see today.

“Is this a picture of our solar system when it was 13 million years old?” asks Kalas. “We know that our own belt of comets, the Kuiper belt, lost a large fraction of its mass as it evolved, but we don’t have a time machine to go back and see how it was decimated. One of the ways, though, is to study these violent episodes of gravitational disturbance around other young stars that kick out many objects, including planets.”

The disturbance could have been caused by a passing star that perturbed the inner planets, or a second massive planet in the system. The GPI team looked for another large planet closer to the star that may have interacted with the exoplanet, but found nothing outside of a Uranus-sized orbit.

Kalas and Rajan will discuss the observations during a Google+ Hangout On Air at 7 a.m. Hawaii time (noon EST) on Dec. 1 during Extreme Solar Systems III, the third in a series of international meetings on exoplanets that this year takes place on the 20th anniversary of the discovery of the first exoplanet in 1995. Viewers without Google+ accounts may participate via YouTube.

A paper about the results, with Kalas as lead author, was published in the The Astrophysical Journal on Nov. 20, 2015.

Young, 13-million-year-old star

The star, HD 106906, is located 300 light years away in the direction of the constellation Crux and is similar to the sun, but much younger: about 13 million years old, compared to our sun’s 4.5 billion years. Planets are thought to form early in a star’s history, however, and in 2014 a team led by Vanessa Bailey at the University of Arizona discovered a planet HD 106906 b around the star weighing a hefty 11 times Jupiter’s mass and located in the star’s distant suburbs, an astounding 650 AU from the star (one AU is the average distance between Earth and the sun, or 93 million miles).

Planets were not thought to form so far from their star and its surrounding protoplanetary disk, so some suggested that the planet formed much like a star, by condensing from its own swirling cloud of gas and dust. The GPI and Hubble discovery of a lopsided comet belt and possible ring around the planet points instead to a normal formation within the debris disk around the star, but a violent episode that forced it into a more distant orbit.

Kalas and a multi-institutional team using GPI first targeted the star in search of other planets in May 2015 and discovered that it was surrounded by a ring of dusty material very close to the size of our own solar system’s Kuiper Belt. The emptiness of the central region – an area about 50 AU in radius, slightly larger than the region occupied by planets in our solar system – indicates that a planetary system has formed there, Kalas said.

He immediately reanalyzed existing images of the star taken earlier by the Hubble Space Telescope and discovered that the ring of dusty material extended much farther away and was extremely lopsided. On the side facing the planet, the dusty material was vertically thin and spanned nearly the huge distance to the known planet, but on the opposite side the dusty material was vertically thick and truncated.

“These discoveries suggest that the entire planetary system has been recently jostled by an unknown perturbation to its current asymmetric state,” he said. The planet is also unusual in that its orbit is possibly tilted 21 degrees away from the plane of the inner planetary system, whereas most planets typically lie close to a common plane.

Kalas and collaborators hypothesized that the planet may have originated from a position closer to the comet belt, and may have captured dusty material that still orbits the planet. To test the hypothesis, they carefully analyzed the GPI and Hubble observations, revealing three properties about the planet consistent with a large dusty ring or shroud surrounding it. However, for each of the three properties, alternate explanations are possible.

The investigators will be pursuing more sensitive observations with the Hubble Space Telescope to determine if HD 106906b is in fact one of the first exoplanets that resembles Saturn and its ring system.

The inner belt of dust around the star has been confirmed by an independent team using the planet-finding instrument SPHERE on the ESO’s Very Large Telescope in Chile. The lopsided nature of the debris disk was not evident, however, until Kalas called up archival images from Hubble’s Advanced Camera for Surveys.

The GPI Exoplanet Survey, operated by a team of astronomers at UC Berkeley and 23 other institutions, is targeting 600 young stars, all less than approximately 100 million years old, to understand how planetary systems evolve over time and what planetary dynamics could shape the final arrangement of planets like we see in our solar system today. GPI operates on the Gemini South telescope and provides extremely high-resolution, high-contrast direct imaging, integral field spectroscopy and polarimetry of exoplanets.

Among Kalas’s coauthors are UC Berkeley graduate student Jason Wang. The research was supported by the National Science Foundation and NASA’s Nexus for Exoplanet System Science (NExSS) research coordination network sponsored by NASA’s Science Mission Directorate.

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Gemini Planet Imager Exoplanet Survey — One Year Into The Survey

The Gemini Planet Imager Exoplanet Survey (GPIES) is an ambitious three-year study dedicated to imaging young Jupiters and debris disks around nearby stars using the GPI instrument installed on the Gemini South telescope in Chile. On November 12 2015, at the 47th annual meeting of the AAS’s Division for Planetary Sciences in Washington DC, Franck Marchis, Chair of the Exoplanet Research Group of the SETI Institute and a scientist involved in the project since 2004, will report on the status of the survey, emphasizing some discoveries made in its first year.

Led by Bruce Macintosh from Stanford University, the survey began a year ago and has already been highly successful, with several findings already published in peer-reviewed journals.

“This very large survey is observing 600 young stars to look for two things: giant planets orbiting them and debris disks. In our first year, we have already found what GPI was designed to discover — a young Jupiter in orbit around a nearby star,” said Marchis. This discovery was announced in an article published in Science on Oct. 2, 2015 [http://www.sciencemag.org/content/350/6256/64], with an impressive list of 88 co-authors from 39 institutions located in North and South America. “This is modern astronomy at its best,” said Marchis. “These large projects gather energy and creativity from many groups of researchers at various institutions, enabling them to consider different strategies to improve the on-sky efficiency of the instrument and its scientific output.”

Orbital motion of 51 Eri b detected between two H-band observations taken with the Gemini Planet Imager in December 2014 and September 2015. From this motion, and additional observations of the system, the team of astronomers confirmed that this point of light below the star is indeed a planet orbiting 51 Eri and not a brown dwarf passing along our line of sight. (credit: Christian Marois & the GPIES team)

Orbital motion of 51 Eri b detected between two H-band observations taken with the Gemini Planet Imager in December 2014 and September 2015. From this motion, and additional observations of the system, the team of astronomers confirmed that this point of light below the star is indeed a planet orbiting 51 Eri and not a brown dwarf passing along our line of sight. (credit: Christian Marois & the GPIES team)

The survey was officially launched in November 2014. Eight observing runs allowed the study of approximately 160 targets, or a quarter of the sample. Other parts of the survey are more frustrating, though. Due to the incipient El Nino, weather in Chile is worse than expected, with clouds, rain, snow, and atmospheric turbulence too severe even for GPI to fix. Since late June, out of the last 20 nights that team members have spent at the telescope, they’ve only gotten a few hours of good quality data Despite this loss, over which the team of course had no control, they have already published ten peer-reviewed papers in the last year. Two of the findings are described below.

GPI data has revealed that 51 Eri b, the recently discovered Jupiter-like exoplanet around the nearby star 51 Eridani [http://www.gemini.edu/node/12403], indeed has an atmosphere of methane and water, and likely has a mass twice that of Jupiter. The team has continued to observe this planetary system, and observations recorded on Sept. 1, 2015, are most consistent with a planet orbiting 51 Eri and not a brown dwarf passing along our line of sight.

“Thanks to GPI’s incredible precision, we can demonstrate that the odds are vanishingly small that 51 Eri b is actually a brown dwarf that has a chance alignment with this star. In fact it’s five times more likely that I’ll be struck by lightning this year than future data will show this is not a planet orbiting 51 Eri” said Eric Nielsen, a postdoctoral scholar at the SETI Institute and one of the authors of the paper recently accepted for publication in the Astrophysical Journal Letters [http://arxiv.org/abs/1509.07514]. Another author of this study, SETI Research Experience for Undergraduates student Sarah Blunt, analyzed the motion of 51 Eri b and found it to be completely consistent with a planet on an approximately 40-year orbit around its host star.

GPI detection of dust-scattered star light around HD 131835 in H-band linearly polarized intensity. The focal plane mask (filled black circle) was used to block the light from the star (white x). The stronger forward scattering makes the front (NW) side of the disk more apparent. A weaker brightness asymmetry is detected along the major axis with the NE side being brighter than the SW side. By studying resolved images of debris disks, we hope to better understand the giant planet formation and evolution environment (credits: Li-Wei Hung & the GPIES team)

GPI detection of dust-scattered star light around HD 131835 in H-band linearly polarized intensity. The focal plane mask (filled black circle) was used to block the light from the star (white x). The stronger forward scattering makes the front (NW) side of the disk more apparent. A weaker brightness asymmetry is detected along the major axis with the NE side being brighter than the SW side. By studying resolved images of debris disks, we hope to better understand the giant planet formation and evolution environment (credits: Li-Wei Hung & the GPIES team)

The team has also discovered and imaged disks of dusty debris around several stars. Astronomers believe that these are planetary systems that are still forming their planets. Some have complex structures because they host planets and fragments of the asteroidal and cometary materials that formed those planets. One such system is HD 131835: a massive 15 Myr-old star located 400 light-years from Earth. Using GPI’s high-contrast capability, the team imaged this disk for the first time in near-infrared light in May 2015.

“The disk shows different morphology when observed in different wavelengths. Unlike the extended disk previously imaged in thermal emission, our GPI observations show a disk that has a ring-like structure, indicating that the large grains are distributed differently from the small ones. In addition, we discovered an asymmetry in the disk along its major axis. What causes this disk to be asymmetric is the subject of ongoing investigation, “ said Li-Wei Hung, a graduate student in the UCLA Department of Physics and Astronomy and lead author of the article submitted to the Astrophysical Journal Astrophysical Journal Letters. As asymmetries like the one seen in the system may be due to the gravitational influence of an unseen planet, more detailed observational study could one day confirm its existence.

As the GPIES survey enters in its second year, we are collaborating with the Gemini Observatory to continue to improve the instrument. The Gemini South telescope primary mirror was recently re-coated with silver to improve reflectivity, and the GPI instrument was equipped with a new cooling system to optimize performance.

“Continued collaboration between the Gemini Observatory and the GPIES collaboration has worked really well — we’re learning a lot about how it performs in the field and interacts with the atmosphere, and are working to make GPI an even a better instrument to see even fainter and closer planets,” said Bruce Macintosh, principal investigator of the project and professor at Stanford University.

 

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Publications

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Astronomers discover “young Jupiter” exoplanet

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GPI First Light 2014

Press-releases published on January 7th 2014

  • Gemini Observatory

Gemini Planet Imager First Light!
http://www.gemini.edu/node/12113

  • LLNL

Out of this world first light images emerge from Gemini Planet Imager
https://www.llnl.gov/news/newsreleases/2014/Jan/NR-14-01-01.html#.Usw_Z2RDtlM

  • STSCI

STScI Astronomers Help Develop and Operate World’s Most Powerful Planet Finder
http://hubblesite.org/newscenter/archive/releases/2014/08/full/

  • SETI Institute

World’s Most Powerful Planet Finder Turns its Eye to the Sky
http://www.seti.org/seti-institute/press-release/worlds-most-powerful-planet-finder-gemini-planet-imager-first-light-images

  • University of Montreal (in French)

L’imageur d’exoplanètes le plus puissant au monde entame sa mission
http://www.nouvelles.umontreal.ca/recherche/sciences-technologies/20140107-limageur-dexoplanetes-le-plus-puissant-au-monde-entame-sa-mission.html

  • AMNH

Museum-Built Device Helping Astronomers Search for Exoplanets
http://www.amnh.org/explore/news-blogs/research-posts/museum-built-device-helping-astronomers-search-for-exoplanets

  • ASU

ASU professor, students part of Gemini Planet Imager team
https://asunews.asu.edu/20140107-gemini-planet-imager?utm_source=twitterfeed&utm_medium=twitter

  • Gemini Obs-SETI (in Spanish)

El Espectrógrafo y Captador de Imágenes más poderoso del Mundo mira al cielo: la Primera Luz del Captador de Imágenes de Planetas de Gemini
http://www.seti.org/seti-institute/press-release/el-espectr%C3%B3grafo-y-captador-de-im%C3%A1genes-m%C3%A1s-poderoso-del-mundo-mira-al

  • UCSC

World’s most powerful exoplanet camera looks skyward
http://news.ucsc.edu/2014/01/planet-imager.html

  • JPL

Powerful Planet Finder Turns Its Eye to the Sky
http://www.jpl.nasa.gov/news/news.php?release=2014-008

 

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Main Institutions

Details 

AMNH American Museum of Natural History (AMNH): AMNH was leading the design and testing of GPI’s apodized-pupil Lyot coronagraph and part of the EPO.

ASU Arizona State University: This university is hosting a team in charge of the target selection

 

UniversityOfToronto Dunlap Institute of the University of Toronto: The team at Dunlap Institute is providing its expertise in data-processing


gemini_logo_long Gemini Observatory: Gemini Observatory is leading the on-sky commissioning of the GPI instrument

NRC-oval_old Herzberg Institute of Astrophysics (HIA): Canada’s Herzberg Institute was responsible for the opto-mechanical structure (OMSS) of GPI and the top-level computer (TLC) that connects the subsystems to each other and the observatory. HIA is also collaborating on control algorithms for the AO system.

JPL Jet Propulsion Laboratory (JPL): JPL was responsible for the precision infrared wavefront-calibration system.

llnl Lawrence Livermore National Laboratory (LLNL): LLNL is the lead institution for the  GPI instrument, responsible for the overall design and project management, and the real-time adaptive optics system.

Lowell_small Lowell Observatory:The team at Lowell Observatory is providing its expertise in modeling exoplanet atmospheres


NASAAmesLogoNASA Ames: NASA Ames is co-leading the theory effort of the campaign by developing and providing models of exoplanets.

SETI-Logo SETI Institute: The SETI Institute is co-leading the Education and Public Outreach effort and in charge of setting up and maintaining the remote control room facility. SETI Institute is the lead institution for the GPIES campaign

STScI_logo_1STSCI:The Space telescope Institute is providing the data analysis pipeline to extract planetary signals from GPI data

Logo-UdeMUniversite de Montreal: University de Montreal is providing the data analysis pipeline to extract planetary signals from GPI data, and collaborated with UCLA on the design of the spectrograph.

UCBerkeley_logo University of California, Berkeley (UCB): Several science team members are hosted at this university

UCLA logo University of California, Los Angeles (UCLA): The Infrared Instrumentation Laboratory was responsible for the construction of the GPI science instrument, a near-IR integral field spectrograph and the science team provides expertise in debris disk imaging and polarimetry

Ucsc_logo University of California, Santa Cruz (UCSC): GPI integration and testing has been taken place since 2010 at the UC Santa Cruz Laboratory for Adaptive Optics. A team is providing its expertise in modeling exoplanet atmospheres

UGA_logo University of Georgia: This university is hosting a team in charge of the target selection

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The Team

The GPIES team is led by the Principal Investigator Bruce Macintosh assisted by several Lead co-Investigators including James R. Graham, Travis Barman, Rene Doyon, Daniel Fabrycky, Michael Fitzgerald, Paul Kalas, Quinn Konopacky, Franck Marchis, Mark Marley, Christian Marois,Jennifer Patience, Marshall Perrin, Ben Oppenheimer and Inseok Song. The entire team is composed of ~50 investigators, including several postdoctoral fellows and graduate students, from universities and research centers located in the U.S.A., U.K., Canada, Australia, Argentina, Brazil and Chile.

The team meets regularly through the GPIES Science meetings whose first session was organized at the SETI Institute on October 11-13 2011, and the second one at the University of Toronto on June 13-14 2012. These meeting give an opportunity to the team to discuss the progress on the integration of instrument, design the observing campaign, organize the data processing and analysis pipeline, discuss the latest results in the field of exoplanets.

The picture below shows the attendees at the first GPIES Science Workshop in June 2011. All members of the GPIES team have read and agree to abide by the policies set forth in the Gemini Project Policies Document. We committed to releasing fully processed images, including speckle suppression by our standard pipeline, in incremental releases approximately 18 months after the campaign begins.
Group picture of the June 2011 GPIES Science Meeting (Credit: SETI Institute)

Group picture of the June 2011 GPIES Science Meeting (Credit: SETI Institute)

Group picture of the June 2011 GPIES Science Meeting (Credit: SETI Institute)

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GPI Contrast Curves

These are 5-sigma contrast levels achievable with different wavefront sensor sensitivity levels and one-hour integrations. The simulations are done over two R = 45 spectral channels, where the central wavelength is 1.65 microns and SDI has been applied over the 1.579-1.624 micron region. The dramatic improvement in contrast up to about 0.2 arcsec separation is due to speckle suppression. Click on the image to magnify.

 

These are 5-sigma contrast levels achievable with different wavefront sensor sensitivity levels and one-hour integrations. The simulations are done over two R = 45 spectral channels, where the central wavelength is 1.65 microns and SDI has been applied over the 1.579-1.624 micron region. The dramatic improvement in contrast up to about 0.2 arcsec separation is due to speckle suppression. Click on the image to magnify.

 

The combination of ADI (angular differential imaging) and SDI (spectral differential imaging) speckle suppression techniques greatly improves the contrast achievable with GPI. Contrast depends strongly on the performance of the wavefront sensor: for a star with a given I magnitude, a wavefront sensor that can lock on I = 9 stars will perform much better than one that requires I = 5 stars. Contrast also depends on the spectral type of the target star: since H band data will be taken, later spectral types will be brighter in H band than earlier spectral types for the same I magnitude.

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The Gemini South Telescope

GPI is mounted on a side port of the instrument support structure of the Gemini South telescope. More information about Gemini Telescope may be found here

The Gemini Telescopes are located in Hawaii and in Chile. Both telescopes have primary mirrors that are 8 meters in diameter (Photo: Paul Kalas)

The Gemini Telescopes are located in Hawaii and in Chile. Both telescopes have primary mirrors that are 8 meters in diameter (Photo: Paul Kalas)

The Gemini Observatory is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and SECYT (Argentina).

Geminipartners

The Gemini Observatory is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and SECYT (Argentina).


Gemini’s Mission

To advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.”


 

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