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HIFI H eterodyne I nstrument for the F ar I nfrared (The high resolution spectrometer for Herschel). Michel Fich. Outline. HIFI science goals Water! Key Projects instrument characteristics the Canadian instrument contribution: the LSU
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HIFI Heterodyne Instrument for the Far Infrared (The high resolution spectrometer for Herschel) Michel Fich HIFI: Submm Workshop, 15 Aug, 2006
Outline • HIFI science goals • Water! • Key Projects • instrument characteristics • the Canadian instrument contribution: the LSU • how to use HIFI – observing modes, integration times • proposing for HIFI time • support for Canadian astronomers • the Canadian HIFI team • tools HIFI: Submm Workshop, 15 Aug, 2006
Herschel Main Scientific Objectives Formation and evolution of galaxies and clusters in the early universe • Star formation rates, bolometric luminosities, AGN structure • Evolution of chemical elements Formation of stars & planets and physics of the interstellar medium • Tracers of structure, kinematics, chemistry in star forming regions • Circulation/enrichment of the interstellar medium • Astrochemistry – WATER • Detailed studies of nearby resolvable galaxies Cometary, planetary, and satellite atmospheres • History of the solar system • Pristine material in comets • Water activity HIFI: Submm Workshop, 15 Aug, 2006
HIFI Core Science • ISM in Galaxies: • Normal galaxies • Physical properties • of star-forming ISM • ISM in the Milky Way: • Structure • Dynamics (pressure) • Composition (gradients) • Dense cores and star-formation: • Dynamics • Role of Water • Disks • Late stages of stellar evolution: • Winds • Shells • Asymmetries • Composition • Solar System: • Water in Giant Planets • Chemistry Martian atmosphere HIFI: Submm Workshop, 15 Aug, 2006
Science with HIFI – Water HIFI: Submm Workshop, 15 Aug, 2006
Science with HIFI – Water SWAS result HIFI: Submm Workshop, 15 Aug, 2006
Example – WATER in intermediate mass star forming region • define intermediate mass as 100 – 1000 Lsun • spherical core, –1.5 power-law • assumed water abundance 10-6 H2 • all frozen out at T < 20 K • Monte Carlo solution to radiative transfer (RATRAN) • run until “lowest” 7 lines in HIFI bands converged with S/N=5 • convolve to HIFI beam appropriate for line frequency • at centre of core • sample spectra shown for 1000 Lsun (left) and 100 Lsun (right), 100 Msun (top) and 10 Msun (bottom) HIFI: Submm Workshop, 15 Aug, 2006
557 GHz ortho (2-1) 61K HIFI: Submm Workshop, 15 Aug, 2006
1670 GHz ortho (3-1) 114K HIFI: Submm Workshop, 15 Aug, 2006
1661 GHz ortho (4-3) 194K HIFI: Submm Workshop, 15 Aug, 2006
1163 GHz ortho (7-6) 305K HIFI: Submm Workshop, 15 Aug, 2006
Molecular Lines visible with HIFI Plus lines of HD, HD+, H2D, 6LiH, 7LiH, CH, CH+, NH, NH+, NeH+, HF, SH, SH+, HCl, FeH, SiH, SiH+, CH2, NH2, NH3, … plus many lines from larger molecules HIFI: Submm Workshop, 15 Aug, 2006
Science with HIFI – [CII] in distant galaxies HIFI: Submm Workshop, 15 Aug, 2006
HIFI Key Projects (Guaranteed Time) • water in star forming regions • low mass: pre-stellar, Class 0, Class 1, outflows • intermediate mass: embedded (led by Doug Johnstone) • high mass: pre-stellar, hot cores, maps • disks • hydrides • Ori B maps and spectral surveys • Ori KL, Ori-South (led by Rene Plume), bar maps • warm ISM • PDRs, diffuse, shocks, low-UV, hydrides, C-clusters (Peter Martin on team) • Solar System • comets, mars, outer solar system • evolved stars • extragalactic • galactic centre, star bursts, ultra-luminous, AGNs, Cen A, metal-poor HIFI: Submm Workshop, 15 Aug, 2006
HIFI Instrument Characteristics • HIFI designed for: • - Spectral Scans and Spectral line surveys • - Very high spectral resolution • - Widest possible coverage in the unexplored FIR/Submm range • Frequency coverage: • 480 – 1250 GHz (625-240 m) • 1410 – 1910 GHz (212-157 m) • 2. Sensitivity • Near-quantum noise limit sensitivity • IF bandwidth/Resolution: • - 4 GHz (in 2 polarisations) • - 140 – 280 kHz –0.5 and 1 MHz • 3. Calibration Accuracy: 10% baseline; 3% goal HIFI Implementation: Heterodyne spectroscopy • single pixel on the sky • very high spectral resolution • 7 dual-pol mixer bands • 480-1250 GHz (625-240 mm) 5x2 SIS mixers, IF 4-8 GHz • 1410-1910 GHz(212-157 mm; 2x2 HEB mixers, IF 2.4-4.8 GHz • 14 LO sub-bands • LO source unit in common • LO multiplier chains • 2 spectrometer systems; • for each polarisation - auto-correlator spectrometer - acousto-optical spectrometer HIFI: Submm Workshop, 15 Aug, 2006
HIFI Design block diagram HIFI: Submm Workshop, 15 Aug, 2006
HIFI Local Oscillator Source Unit (LSU) The Canadian Hardware Contribution to HIFI • Flight Model assembled, undergoing tests. Due to be shipped to SRON first week of Sept. 2006 • the LSU dimensions are 265(H) x 424(L) x 286(W) mm. HIFI: Submm Workshop, 15 Aug, 2006
Latest update LO chain performance:Bands 1-4 by RPG; Bands 5, 6L, 6H by JPL HIFI: Submm Workshop, 15 Aug, 2006
HIFI Flight Mixer Performanceat Unit level (open symbols) and after integration in the FPU HIFI: Submm Workshop, 15 Aug, 2006
Band-3 SIS Noise Temperature as function of IF Band-6 HEB Noise Temperature as function of IF • IN HIFI: ONE FREQUENCY Band is working at a time with 2 mixers; • In orthogonal polarisation, also for redundancy. • One LO band, with 2 sub-bands, match the corresponding mixer band HIFI: Submm Workshop, 15 Aug, 2006
WBO FM with 1.1 MHz resolution and 4GHz bandwidth HIFI: Submm Workshop, 15 Aug, 2006
HIFI-HRS (auto-correlator) FM Capabilities 2 HRS FM modules HIFI: Submm Workshop, 15 Aug, 2006
HIFI Observing Modes • Dual Beam Switch with internal copper and telescope nod • Position Switch efficiency depending on off-position slew • Frequency Switch with switching LSU • Optimum AOT depends on stability of Telescope-Instrument System HIFI: Submm Workshop, 15 Aug, 2006
HIFI Band Sensitivities HIFI: Submm Workshop, 15 Aug, 2006
Estimating integration times • Time estimate recipe available on web at http://www.sron.rug.nl/hifi_icc/time_estimator.html • overheads not well known until after launch • slew times: large distances, scanning, small distances (beam-switching) • pointing/focus/calibration times • re-tuning times: within band and changing bands • data downloads and command uploads HIFI: Submm Workshop, 15 Aug, 2006
Updated Herschel Observing Proposal AO Timeline • AO KP (GT and OT) issue 1/02/2007 • KP GT proposal deadline 5/04/2007 • KP GT result official 5/07/2007 • KP OT proposal deadline 1/11/2007 • KP OT result official 28/02/2008 • AO ‘regular’ GT cycle 1 issue 28/02/2008 • AO ‘regular’ GT cycle 1 proposal deadline 3/04/2008 • GT result official 5/06/2008 • AO OT issue 1/02/2009? AO = Announcement of Opportunity KP = Key Project GT = Guaranteed Time OT = Open Time HIFI: Submm Workshop, 15 Aug, 2006
Support for Canadian Astronomers • Canadian HIFI Steering Committee • Michel Fich* (University of Waterloo) Canadian Lead Co-Investigator • Doug Johnstone* (NRC/HIA) • Peter Martin* (University of Toronto) • Henry Matthews (NRC/HIA/DAO/DRAO) • Bill McCutcheon (University of British Columbia) • Rene Plume* (University of Calgary) * “Astronomy Co-Investigator” - member of the international HIFI Science Team • Canadian HIFI staff members of HIFI Instrument Control Centre (ICC) • Science support specialist (University of Waterloo): job available! • Instrument support specialist (SRON): Kevin Edwards HIFI: Submm Workshop, 15 Aug, 2006
Tools for HIFI • Observing tool is HSPOT (Herschel adaptation of Spitzer SPOT tool) • Analysis tool is HICLASS (HIFI adaptation of CLASS) • Tools based on Linux and Windows platforms but Canadian contribution is Mac OSX version – not fully functional because database not available for Macs • may need to learn some Jython (Java/Python implementation) to write observing scripts, etc. HIFI: Submm Workshop, 15 Aug, 2006
Canadian HIFI strategy is to maximize success rate on Open Time (OT) Proposals • Canadian staff and Science Team members available as a resource to all Canadian astronomers to help with proposals • Canadian HIFI Workshop for potential users in mid-2009 • observing assistance, data analysis advice and software support will be available • http://astro.uwaterloo.ca/HIFI • email: hifi@astro.uwaterloo.ca HIFI: Submm Workshop, 15 Aug, 2006