Herschel HIFI | Jürgen Stutzki for the HIFI team | Universität zu Köln| Pag. 1

Herschel HIFI:the Heterodyn Instrument for the Far-Infrared

PI-Institut: SRON, Groningen

– PI/CoPI-Team: Frank Helmich(PI), Thijs de Graauw, SRON Groningen Jürgen Stutzki, KOSMA, Universität zu Köln

Tom Phillips, Caltech, USAEmmanuel Caux, CNRS, Toulouse

– major partner nationsNL, D, USA, F

in total 25 institutes form 13 nations

HIFI Focal Plane Unit

Herschel HIFI | Jürgen Stutzki for the HIFI team | Universität zu Köln| Pag. 2

The heterodyne principle – mixing light

– We mix the sky signal with an ultra-stable local signal such that the difference frequencies can be detected

– This difference signal can be electronically amplified and analysed

– The difference signal contains all information of the sky signal

Herschel HIFI | Jürgen Stutzki for the HIFI team | Universität zu Köln| Pag. 3

Herschel HIFI:Key technologies

– superconducting heterodyne mixers

– at close to quantum-limited operation

– local oscillators, without mechanical tuning elements

– up to frequencies of 2 TeraHz

– compact and low power spectroscopy backends

– complex total setup with 2x7 frontends7 frequency bands

2 polarizations each

only previous heterodyne instruments in space: NASA Submm Wave Astronomy Satellite (60 cm telescope;

557 GHz water ground state transition)

and very similar: ODIN (astro & atmospheric)

Herschel HIFI | Jürgen Stutzki for the HIFI team | Universität zu Köln| Pag. 4

Herschel HIFI:The life-cycle of gas and dust in galaxies

Solar System• Water in Giant

Planets• Chemistry Martian

atmosphere

ISM in Galaxies• Physical conditions• Star formation

Star formation• Physical conditions• Chemistry• Energetics• Dynamics• Role of Water

ISM in the Milky Way• Physical conditions• Chemistry• Energetics• Dynamics• Isotopic gradients

Stellar evolution• Mass loss• Composition

Herschel HIFI | Jürgen Stutzki for the HIFI team | Universität zu Köln| Pag. 5

Herschel HIFI: the need for high spectral resolution

Herschel HIFI | Jürgen Stutzki for the HIFI team | Universität zu Köln| Pag. 5

example 1: bipolar outflow from young starline profile

line width

• thermal velocity-distribution (0.1-1 km/s)

• turbulent motion (3-10 km/s) systematic motions

• outflows (10-100 km/s)

• rotation (3-30 km/s)

• etc.

thus: R = λ/Δλ =C/Δv= 3000 – 3x106 needed

example 2: galaxy rotation

Herschel HIFI | Jürgen Stutzki for the HIFI team | Universität zu Köln| Pag. 6

Herschel HIFI unique science – SPECTRAL SURVEYS

– HIFI is able to scan the complete frequency range between 480-1250 GHz and 1.4-1.9 THz

Caux et al. – IRAS16293HIFI – Instrument Level Test

Herschel HIFI | Jürgen Stutzki for the HIFI team | Universität zu Köln| Pag. 7

Herschel HIFI unique science – SPECTRAL SURVEYS

goals

• To determine physical and chemical conditions

• To determine tracers for different processes going on at the same time

• To determine evolution, based on chemical clocks

• To find new species

• Observations of one typical object per class, three high-mass star-forming regions are chosen.

• Analysis execised with gas-cell data obtained in the laboratory

Herschel HIFI | Jürgen Stutzki for the HIFI team | Universität zu Köln| Pag. 8

HIFI Key Programmeshttp://herschel.esac.esa.int/Key_Programmes.shtml

Star-formationWISH – water is star forming regions HEXOS – Herschel/hifi observations of EXtrordinary Sources: the Orion and Sgr B2 regionsHS3F = HIFI Spectral Surveys of Star-Forming regions

ISM WADI – Warm And Dense ISMPRISMAS – PRobing InterStellar Molecules with Absorption line Studies

ExtragalacticHEXGAL – the HIFI EXtraGALactic key project

Stellar EvolutionHIFISTARS – The physical and chemical properties of the circumstellar environments around evolved stars

HSSO - Herschel Solar System ObjectsWater and related chemistry in the Solar System

THANK YOU

Jürgen Stutzkifor the HIFI teamstutzki@ph1.uni-koeln.de

left out due to the limited time:

• many other exciting scientific opportunities with HIFI• very exciting technological advancements, with spin-off to many other new projects in the field

Looking forward to the continuing discussions today and tomorrow ...

Herschel HIFI