277 research outputs found

    Signposts of Planets Observed by SEEDS

    Get PDF
    The Strategic Exploration of Exoplanets and Disks at Subaru (SEEDS) is the first strategic observing program (SSOPs) awarded by the National Astronomical Observatory of Japan (NAOJ). SEEDS targets a broad sample of stars that span a wide range of masses and ages to explore the formation and evolution of planetary systems. This survey has been awarded 120 nights over five years time to observe nearly 500 stars. Currently in the second year, SEEDS has already produced exciting new results for the protoplanetary disk AB AUf, transitional disk LkCa15, and nearby companion to GJ 758. We present the survey architecture, performance, recent results, and the projected sample. Finally, we will discuss planned upgrades to the high contrast instrumentation at the Subar

    SEEDS Moving Groups and CHARIS Status Updates

    Get PDF
    We present the status update for the SEEDS Moving Groups category. To date, we have observed 59 targets and currently have more than 20 candidates. We also present the expected scientific capabilities of CHARIS, the Coronagraphic High Angular Resolution Imaging Spectrograph, which is being built for the Subaru 8.2 m telescope of the National Astronomical Observatory of Japan. CHARIS will be implemented behind the new extreme adaptive optics system at Subaru, SCExAO, and the existing 188-actuator system AO188. CHARIS will offer three observing modes over near~infrared wavelengths from 0.9 to 2.4 microns (the y-, J-, H-, and K-bands), including a low-spectral-resolution mode covering this entire wavelength range and a high-resolution mode within a single band. With these capabilities, CHARIS will offer exceptional sensitivity for discovering giant exoplanets, and will enable detailed characterization of their atmospheres, CHARIS, the only planned high-contrast integral field spectrograph on an 8m-class telescope in the Northern Hemisphere, will complement the similar instruments such as Project 1640 at Palomar, and GPI and SPHERE in Chile

    SEEDS Moving Group Status Update

    Get PDF
    I will summarize the current status of the SEEDS Moving Group category and describe the importance of this sub-sample for the entire SEEDS survey. This presentation will include analysis of the sensitivity for the Moving Groups with general a comparison to other the other sub-categories. I will discuss the future impact of the Subaru SCExAO system for these targets and the advantage of using a specialized integral field spectrograph. Finally, I will present the impact of a pupil grid mask in order to produce fiducial spots in the focal plane that can be used for both photometry and astrometry

    Exoplanetary Science: Instrumentation, Observations, and Expectations

    Get PDF
    More than 700 exoplanets have been discovered and studied using indirect techniques, leading our field into the exciting new era of comparative exoplanetology. However, the direct detection of exoplanetary systems still remains at the sensitivity limits of both ground- and space-based observatories. The development of new technologies for adaptive optics systems and high contrast instruments continues to increase the ability to directly study exoplanets. The scientific impact of these developments has promising prospects for both short and long timescales. In my talk, I will discuss recent highlights from the SEEDS survey and the current instrumentation in use at the Subaru telescope. SEEDS is a high contrast imaging strategic observing program with 120 nights of time allocated at the NAOJ's flagship optical and infrared telescope. I will also describe new instrumentation I designed to improve the SEEDS capabilities and efficiency. Finally, I will briefly discuss the conceptual design of a transiting planet camera to fly as a potential second generation instrument on-board NASA's SOFIA observatory

    Subaru SEEDS Survey of Exoplanets and Disks

    Get PDF
    The Strategic Exploration of Exoplanets and Disks at Subaru (SEEDS) is the first strategic observing program (SSOPs) awarded by the National Astronomical Observatory of Japan (NAOJ). SEEDS targets a broad sample of stars that span a wide range of masses and ages to explore the formation and evolution of planetary systems. This survey has been awarded 120 nights over five years time to observe nearly 500 stars. Currently in the second year, SEEDS has already produced exciting new results for the protoplanetary disk AB Aur, transitional disk LkCa15, and nearby companion to GJ 758. We present the survey architecture, performance, recent results, and the projected sample. Finally, we will discuss planned upgrades to the high contrast instrumentation at the Subaru Telescop

    Scientific Design of a High Contrast Integral Field Spectrograph for the Subaru Telescope

    Get PDF
    Ground based telescopes equipped with adaptive optics systems and specialized science cameras are now capable of directly detecting extrasolar planets. We present the scientific design for a high contrast integral field spectrograph for the Subaru Telescope. This lenslet based integral field spectrograph will be implemented into the new extreme adaptive optics system at Subaru, called SCExAO

    The 2MASS Wide-Field T Dwarf Search. II. Discovery of Three T Dwarfs in the Southern Hemisphere

    Full text link
    We present the discovery of three new Southern Hemisphere T dwarfs identified in the Two Micron All Sky Survey. These objects, 2MASS 0348-6022, 2MASS 0516-0445, and 2MASS 2228-4310, have classifications T7, T5.5, and T6.5, respectively. Using linear absolute magnitude/spectral type relations derived from T dwarfs with measured parallaxes, we estimate spectrophotometric distances for these discoveries; the closest, 2MASS 0348-6022, is likely within 10 pc of the Sun. Proper motions and estimated tangential velocities are consistent with membership in the Galactic disk population. We also list Southern Hemisphere T dwarf candidates that were either not found in subsequent near-infrared imaging observations and are most likely uncatalogued minor planets, or have near-infrared spectra consistent with background stars.Comment: 12 pages including 4 figures (one as jpeg), accepted to A

    Lenslet Array to Further Suppress Star Light for Direct Exoplanet Detection

    Get PDF
    Direct imaging plays a key role in the detection and characterization of exoplanets orbiting within its host star's habitable zone. Many innovative ideas for starlight suppression and wavefront control have been proposed and developed over the past decade. However, several technological challenges still lie ahead to achieve the required contrast, including controlling the observatory pointing performance, fabricating occulting masks with tight optical tolerances, developing wavefront control algorithms, controlling stray light, advancing single photon detecting detectors, and integrated system-level issues. This paper explores how a lenslet array and pinhole mask may be implemented to further suppress uncorrected starlight that leaks through the occulting mask. An external occulter, or star shade, is simulated to demonstrate this concept, although this approach can be implemented for internal coronagraphs as well. We describe how to use simple relay optics to control the scene near the inner working angle and the level of the suppression expected. Furthermore, if the lenslet array is the input to an integral field spectrograph, as planned for the WFIRST mission, the spectral content of the exoplanet atmospheres can be obtained to determine if the observed planet is habitable and ultimately, if it is inhabited

    A New Brown Dwarf Desert? A Scarcity of Wide Ultracool Binaries

    Get PDF
    We present the results of a deep-imaging search for wide companions to low-mass stars and brown dwarfs using NSFCam on IRTF. We searched a sample of 132 M7-L8 dwarfs to magnitude limits of J∼20.5J \sim 20.5 and K∼18.5K \sim 18.5, corresponding to secondary-primary mass ratios of ∼0.5\sim 0.5. No companions were found with separations between 2{\arcsec} to 31{\arcsec} (∼\sim40 AU to ∼\sim1000 AU). This null result implies a wide companion frequency below 2.3% at the 95% confidence level within the sensitivity limits of the survey. Preliminary modeling efforts indicate that we could have detected 85% of companions more massive than 0.05M⊙0.05 M_{\odot} and 50% above 0.03M⊙0.03 M_{\odot}.Comment: 27 pages, 8 figures, 3 tables: accepted to the Astronomical Journa

    A dual-mask coronagraph for observing faint companions to binary stars

    Full text link
    Observations of binary stars for faint companions with conventional coronagraphic methods are challenging, as both targets will be bright enough to obscure any nearby faint companions if their scattered light is not suppressed. We propose coronagraphic examination of binary stars using an apodized pupil Lyot coronagraph and a pair of actively-controlled image plane masks to suppress both stars simultaneously. The performance is compared to imaging with a band-limited mask, a dual-mask Lyot coronagraph and with no coronagraph at all. An imaging procedure and control system for the masks are also described.Comment: 17 pages, 6 figure
    • …
    corecore