Download presentation
Presentation is loading. Please wait.
Published byHector Hawkins Modified over 8 years ago
1
Gemini Observatory Giant Telescope Science http://www.gemini.edu http://www.gemini.edu/node/11472 2011.04.05 J. Y. Seok
2
2 Content I.Introduction of the observatory II.Instruments I.GMOS II.ALTAIR III.NIRI IV.T-ReCS III.Key sciences IV.How to use Gemini
3
3 Gemini observatory Two optical/IR 8.1m on the two best sites Built in 2000 Gemini South (right): on 2,737 m at Cerro Pachón Gemini North (left): on 4,214 m at Mauna Kea, Hawai'I 7 nations (US, UK, Canada, Chile, Australia, Brazil, Argentina) Over 750 scientific papers published (at April 15, 2010)
4
Two principal performance goals The best image quality possible from the ground for telescopes of their size. 1.The thin (~20 cm thick) primary mirror of each telescope rests on a bed of 120 hydraulic actuators 2.The 1-meter diameter secondary mirrors are capable of rapid tip-tilt corrective motions 3.Vents on the cylindrical walls of each dome can be opened by as much as 10 meters 4.The telescopes are equipped (or are being equipped) with adaptive optics (AO) systems The cleanest possible (i.e., lowest possible emissivity) telescopes, for optimal infrared observing from the ground. 1.choosing excellent infrared sites for the two telescopes 2.coating all of the Gemini telescope mirrors with silver 4
5
5 Uniqueness Queue scheduling Multi-instrument configuration on GN/GS 3 science ranking bands (SRB) –90% of SRB1 completed in the required condition (if classical, ~35% completion) Targets of Opportunity (ToO) Time-critical events Rapid ToO: current observation interrupted for turnarounds on the order of 15 mins. Silver-coated primary mirrors Reduce thermal IR emission of telescope by a factor of 2-3 compared to Al coatings
6
6 Instruments
7
7 Gemini Multi-Object Spectrographs (GMOS) Camera FoV: 5.5’ 5.5’, Pixel: ~0.073” Grating: 0.36-1.10 µm R: 500 (widest slit) to 4400 (0.5”), and 8800 (0.25”) Filter SDSS filters (& Z,Y) + narrow filters (SII, HeII, Ha, OIII) 3 types of spectroscopy Long-slit –covers the full extent of the CCD package (3 x 2048 pixels) with two small gaps (2.8”). –Width & length: 0.25~5”, 330/108”
8
8 Multi-slit –custom-designed, laser-milled masks. –obtaining spectra of several hundred objects simultaneously Integral field unit (IFU) –0.2” fibers covering a 5” 7” fov Image dither steps of at least 5” in the X-direction
9
9 Near Infrared Imager and Spectrometer (NIRI) Imaging and spectroscopy in the 1-5 micron wavelength region Detector: 1024x1024 ALADDIN InSb array 3 cameras: f/32, f/14, and f/6 Imaging mode –A large number of broad- and narrow band filters are available. Spectroscopy –f/6:1-5 um –f/32: JHK only –Various slit widths –R ~ 450-1650 NIRI+AO system available
10
10 ALTtitude conjugate Adaptive optics for the InfraRed (ALTAIR) Natural/laser guide star (N/LGS) AO system of GN Available for use with NIRI at f/14 or f/32, either with a N/LGS, for all imaging except in the M band Three f/32 grisms covering 1.05-2.41μm also available for use with ALTAIR Field lens option W/O, high quality correction within 5-7” from the guide star W/, up to 25” from the guide star: a factor 20 to 30 increase of area M33 45”
11
11 Thermal-Region Camera Spectrograph (T-ReCS) MIR imager and long-slit spectrograph (8-26 um) Imaging –Broad-band (N, Q) and Narrow-band Filter Imaging –Pixel size = 0.09" (fixed) –Field of view = 28.8"×21.6" –# of filters: currently 20, capacity for 24 Spectroscopy –Low resolution: R ~ 100 near 10 µm, R ~ 80 near 20 µm –Medium: R ~ 1000 near 10 µm –Pixel size in spatial direction: 0.09" (fixed) –Slit length & width: 21.6”, 0.21" to 1.32” –LR at 10 µm = 0.022 µm/pix, ∆ = 7.1 µm (entire N band) –LR at 20 µm = 0.033 µm/pix, ∆ = 10.6 µm (entire Q band) –HR at 10 µm = 0.0019 µm/pix, ∆ = 0.6 µm
12
12 lambda/D slits –generally provide the best spectral resolution in good seeing 2*lambda/D slits –better in poor seeing or for fainter sources Similar to Michelle (GN) Ozone band at ~9.5 µm –variable with time and direction –So strong! –Removal using a telluric calibration is essential for N-band spectra.
13
13 Key science Gemini’s First Data, the Galactic Center: page 6 Monitoring the Solar System: page 8 Outer Solar System and Minor Bodies: page 12 Exoplanet Imaging: page 16 Dwarf Objects: page 20 Stellar Disks: page 24 Active Galactic Nuclei: page 28 Supernovae: page 32 Star Formation in the Early Universe: page 36 Early Galaxy Evolution: page 40 Gamma-ray Bursts: page 44
14
14 Monitoring solar system On-going ToO program to monitor and observe the weather on Saturn’s moon Titan With IRTF & a 0.5 m robotic telescope at Lowell observatory “Deep impact” mission Comet 9P/Temple 1 (9P) Collied w/ comet’s nucleus MIR: MICHELLE & T- ReCS Evolution of sillicate feature during impact
15
Exoplanet imaging The first direct image of a planetary family around a normal star K-band AO image of the HR 8799 (~1.5 M , 5 L , much young) planetary system Counterclockwise Keplerian orbital motion seen for all three planets The stellar flux has been subtracted using Angular Differential Imaging (ADI) technique.
16
AGN GMOS IFU NIFS NIFS IFU observation with AO toward NGC 4151 (one of the closest AGN, 13.3 Mpc) Unprecedented, diffraction-limited image Mapped excitation & kinematics of the gas: to study feeding & feedback near the core Most ionized gas originates in a biconical outflow (i.e. mapping AGN feedback), but most molecular gas in the galaxy plane (i.e. source of AGN feeding)
17
SNe GMOS image of M-74 (NGC 628) L: pre-explosion star R: the supernova six months after it exploded (Isaac Newton Telescope) Identified and characterized the progenitor star’s T, L, R, & M: a normal, massive, red supergiant SN 2003gd: normal Type II SN SST image The first time that a RSG progenitor star had been identified on its deathbed prior to going supernova
18
Early Galaxy Evolution Gemini Deep Deep Survey By GMOS multi-object spec mode from 2002: ~100 spectra in single pointings
19
Gamma-ray bursts ToO program (after Swift alert) GRB 090423 IR afterglow shown in NIRI Y, J, & H-band images The most distant object known ever (z=8.2): ~630 million yr of Big Bang (4.6% age of Universe)
20
How to use Gemini Proposal Prepare for 2012A (deadline will be September, 2011) Archival data http://www2.cadc-ccda.hia-iha.nrc-cnrc.gc.ca/gsa/
21
Thank you!
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.