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Hubble Science Briefing . Selecting the best targets for JWST: My personal journey as a MIRI team scientist. Margaret Meixner (STScI, JHU) March 7, 2013. Hubble Science Briefing - Margaret Meixner. Outline of Talk. My personal story as a JWST/MIRI science team member
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Hubble Science Briefing Selecting the best targets for JWST: My personal journey as a MIRI team scientist Margaret Meixner (STScI, JHU) March 7, 2013 Hubble Science Briefing - Margaret Meixner
Outline of Talk • My personal story as a JWST/MIRI science team member • Astronomers prepare now to use the power of JWST(James Webb Space Telescope) • Spitzer and Herschel space observatories find thousands of forming stars in the Magellanic Clouds • Large Magellanic Cloud (LMC) • Small Magellanic Cloud (SMC) • My JWST programs on star formation in the Magellanic Clouds • How JWST will discover more forming stars in nearby, but more distant galaxies Hubble Science Briefing – Margaret Meixner 2 7 March 2013
Margaret Meixner: Member of the JWST/MIRI ScienceTeam Hubble Science Briefing – Margaret Meixner 3 7 March 2013
JWST Sensitivity:-typically detects at an order of magnitude fainter than recent and current observatories-lower is better! Hubble Science Briefing – Margaret Meixner 4 7 March 2013
JWST Sensitivity JWST launches in 2018; appropriate target lists must be developed now… Hubble Science Briefing – Margaret Meixner 5 7 March 2013
James Webb Space Telescope (JWST) Hubble Science Briefing – Margaret Meixner 6 7 March 2013
James Webb Space Telescope (JWST) Hubble Science Briefing – Margaret Meixner 7 7 March 2013
James Webb Space Telescope (JWST) Integrated ScienceInstrument Module Hubble Science Briefing – Margaret Meixner 8 7 March 2013
Integrated Science Instrument Module (ISIM) Hubble Science Briefing – Margaret Meixner 9 7 March 2013
Integrated Science Instrument Module (ISIM) Hubble Science Briefing – Margaret Meixner 10 7 March 2013
James Webb Space Telescope: Webb ~2018 NIRSpec MIRI NIRCam NIRISS 11 7 March 2013
The Mid-InfraRed Instrument(MIRI) spectrograph Imager Hubble Science Briefing – Margaret Meixner 12 7 March 2013
MIRI detector Hubble Science Briefing – Margaret Meixner 13 7 March 2013
MIRI Arrives at Goddard Hubble Science Briefing – Margaret Meixner 14 7 March 2013
MIRI Inspected at Goddard Hubble Science Briefing – Margaret Meixner 15 7 March 2013
MIRI Team Hubble Science Briefing – Margaret Meixner 16 7 March 2013
Why the Magellanic Clouds? They act as a good astrophysical laboratory: • They are nearby: ~50 kpc (LMC) and ~60 kpc (SMC) [the Andromeda Galaxy is about 16 times farther away] • Mean metallicity (Z)* is similar to metallicity of the interstellar medium during Universe’s peak star formation epoch (z**~1.5) • LMC: Z~0.5 x Z • SMC: Z~0.2 x Z • Known tidal interactions between LMC and SMC, possibly the Milky Way • Long History of Studies & used as a proving ground: • Ideal Case study for galaxy evolution *metallicity (Z) = percent of elements other than hydrogen and helium **z = redshift Hubble Science Briefing – Margaret Meixner 17 7 March 2013
Spitzer Survey of the Large Magellanic Cloud (LMC): Surveying the Agents of Galaxy Evolution (SAGE) LMC, SAGE- MIPS: 70 m IRAC 3.6 m: old (evolved) stellar populationsIRAC 8.0 m: dust emission from ISMMIPS 24 m: new massive star formation http://sage.stsci.edu/SAGE team Meixner et al. 2006 Hubble Science Briefing – Margaret Meixner 18 7 March 2013 Meixner et al. 2006
Spitzer wavelengths detect dust, stars & gas http://www.spitzer.caltech.edu/images/2627-sig07-011-The-Spitzer-Space-Telescope-Spectrum JWST briefing - Margaret Meixner 19
LMC: Herschel Inventory of The Agents of Galaxy Evolution (HERITAGE) SPIRE 250 m PACS 160 m PACS 100 m HERITAGE Team; Meixner et al. submitted Hubble Science Briefing – Margaret Meixner 20 7 March 2013
SAGE-SMC: Spitzer IRAC & MIPS Imaging ofSmall Magellanic Cloud (SMC) http://sage.stsci.edu/ old (evolved) stellar populations new massive star formation dust emission from ISM SAGE SMC team Gordon et al. 2011 Hubble Science Briefing – Margaret Meixner 21 7 March 2013
SMC: Herschel HERITAGE SPIRE 250 m PACS 160 m PACS 100 m HERITAGE Team; Meixner et al. submitted Hubble Science Briefing – Margaret Meixner 22 7 March 2013
Why is studying dust important? • Goal of Spitzer and Herschel surveys: • to study lifecycle of baryonic matter using infrared and submillimeter emission from dust. • Why is studying dust important? • Dust is present at the key transition points of this life cycle • It is present in the ISM (which is the origin of the cycle) • Dust enshrouds the young stellar objects as they form • Dust is produced in the stellar winds of dying stars and in the explosive supernovae Hubble Science Briefing – Margaret Meixner 23 7 March 2013
Tracing the Lifecycle of Baryonic Matter: Intermediate mass stars High mass stars credit: http://hea-www.cfa.harvard.edu/CHAMP/EDUCATION/PUBLIC/ICONS/ Hubble Science Briefing – Margaret Meixner 24 7 March 2013
Tracing the Lifecycle of Baryonic Matter: Intermediate mass stars High mass stars YSOs credit: http://hea-www.cfa.harvard.edu/CHAMP/EDUCATION/PUBLIC/ICONS/ Hubble Science Briefing – Margaret Meixner 25 7 March 2013
Young Stellar Object Evolutionary Stages Young Protostar: Main Accretion Phase Herschel Spitzer Evolved Accreting Protostar Thick disk, accreting, HerbigAe/Be Hubble & JWST Hubble & JWST Thin disk, T-Tauri time Hubble Science Briefing – Margaret Meixner 26 7 March 2013
Spitzer Discovers One Thousand Young Stellar Objects in the SMC ~1100 YSO candidates; ~900 new N 66 8.0 mm NGC 346 NGC 602 Sewilo et al. submitted JWST briefing - Margaret Meixner Hubble Science Briefing – Margaret Meixner 27 7 March 2013
Spitzer Discovers Two Thousand Young Stellar Objects in the LMC SAGE IRAC 8 mm Pre-Spitzer: ~20 protostars known Spitzer: ~1000 YSO candidates Whitney, Sewilo et al. (2008) ~1200 YSO candidates Gruendl & Chu (2009) ~1800 unique sources Star Formation Rate: ~0.1M/yr Hubble Science Briefing – Margaret Meixner 28 7 March 2013
Spitzer Discovers Two Thousand Young Stellar Objects in the LMC SAGE IRAC 8 mm Pre-Spitzer: ~20 protostars known Spitzer: ~1000 YSO candidates Whitney, Sewilo et al. (2008) ~1200 YSO candidates Gruendl & Chu (2009) ~1800 unique sources Star Formation Rate: ~0.1 M/yr Hubble Science Briefing – Margaret Meixner 29 7 March 2013
Detailed study by Spitzer finds low-mass YSOs(circles) Carlson et al.2012 30
Detailed study by Herschel finds YSO candidates (red squares) JWST simulation region (next slide) Carlson et al.2012 31
JWST will detect solar-like stars with planet forming disks in the LMC! Seale & Meixner JWST imaging tiles on N113 star formation region Hubble Science Briefing – Margaret Meixner 32 7 March 2013
But it would be useful to get HST data of a field first,as we have for an SMC source NGC 602 SAGE SMC team Gordon et al. 2011 Hubble Science Briefing – Margaret Meixner 33 7 March 2013
Spitzer & HST image of NGC 602 Circles= YSOs Unclassified Stage I Stage I/II Stage II Carlson, et al. 2010 MIPS 24µm IRAC 8.0µm IRAC 3.6µm, 4.5µm, 5.8µm Blue= HST Optical JWST briefing - Margaret Meixner Hubble Science Briefing – Margaret Meixner 34 34
HST image of NGC 602 Hubble Science Briefing – Margaret Meixner 35 35 7 March 2013
JWST will acquire simultaneous spectral and spatial information Hubble Science Briefing – Margaret Meixner 36 7 March 2013
JWST NIRSpec & MIRI Spectroscopy of selected YSOs Example: N113, a massive young stellar object Seale, Sewilo, Meixner Hubble Science Briefing – Margaret Meixner 37 7 March 2013
LMC N113: Spitzer spectrum reveals a hot massive star MIRI Seale et al. 2009 Hubble Science Briefing – Margaret Meixner 38 7 March 2013
JWST: NIRSpec & MIRIIFU spectroscopyreveals the environmental composition of forming stars ISO SWS spectrum Whittet et al. 1996 Hubble Science Briefing – Margaret Meixner 39 7 March 2013
JWST can measure a spectrum of any source detected with Spitzer • In the LMC, we detected 6 million sources • With Spitzer we measured spectra of only 2000 • The faintest sources were unreachable with Spitzer • In the time of 10 seconds to 2 hours, we can measure a spectrum of any source. Hubble Science Briefing – Margaret Meixner 40 7 March 2013
Pursuing SAGE-like studiesin nearby Galaxies • With Spitzer, we imaged the Magellanic Clouds with one minute per pointing. • With JWST MIRI, we can detect the same types of forming stars in galaxies as far away as 1 Mpc in one minute per pointing. • The best galaxies should be well studied by Herschel and Spitzer. • the ISM should be mapped in atomic and molecular gas • the stars should be measured and their past well understood Hubble Science Briefing – Margaret Meixner 41 7 March 2013
M31: angular size of galaxy: 190’x60’ Hubble Science Briefing – Margaret Meixner 42 7 March 2013
M31: 190’ x 2’ strip: total time is ~80 hrs Hubble Science Briefing – Margaret Meixner 43 7 March 2013
M33: 0.889 Mpc, 71’x42’ 44 7 March 2013 Hubble Science Briefing – Margaret Meixner
NGC 6822: 0.490 Mpc, 16’x14’ Hubble Science Briefing – Margaret Meixner 45 7 March 2013
Summary of Talk • Preparing appropriate target lists for JWST, to launch in 2018 • Spitzer and Herschel space observatories discovered thousands of forming stars in the Magellanic Clouds • Hubble has surveyed some fields; need more to prepare for JWST • With JWST I will learn about the nature of the material in forming stars in the Magellanic Clouds: • Do they contain a similar amount of water and organic materials? • Do the solar mass stars have enough circumstellar dust to form planets? • With JWST, I will discover more forming stars in nearby, but more distant galaxies, like M31, M33 and NGC 6822 Hubble Science Briefing – Margaret Meixner 46 7March2013