www.sron.nl/122-lea/hifi.html

01-09-2015
european-citizens-measure-air-pollution-with-their-smartphones

European citizens measure air pollution with their smartphones

A successful Dutch initiative that enlisted the general public to contribute to the understanding of air pollution is being scaled up and running during the International Year of Light and Light-based Technologies 2015 its first Europe-wide citizen campaign: iSPEX-EU. From 1 September to 15 October 2015, thousands of citizens in major European cities will take to their streets, squares and parks to measure air pollution with their smartphone. Participating cities include: Athens, Barcelona, Belgrade, Berlin, Copenhagen, London, Manchester, Milan, and Rome.        Read more (in dutch)
17-07-2015
toward-a-new-picture-of-cosmic-structure-formation-history

Toward a new picture of cosmic structure formation history

SRON astronomer Hiroki Akamatsu will receive a Veni grant from NWO (250 thousand euros) to establish a new picture of structure formation history. To achieve this Akamatsu will make use of observations with the Japanese space telescope Astro-H. He will also participate in the development of a novel imaging spectrometer for its big successor, the space telescope Athena (ESA).         More
15-07-2015
ariel-mission-to-unravel-exoplanet-atmospheres

ARIEL mission to unravel exoplanet atmospheres

An ambitious European mission is being planned to answer fundamental questions about how planetary systems form and evolve. ARIEL will investigate the atmospheres of several hundreds planets orbiting distant stars. It is one of three candidate missions selected last month by the European Space Agency (ESA) for its next medium class science mission, due for launch in 2026. The ARIEL mission concept has been developed by a consortium of more than 50 institutes from 12 countries including the Netherlands. The mission will be presented today at the Pathways 2015 conference in Bern, Switzerland.           More
13-07-2015
the-netherlands-delivers-earth-observation-instrument-tropomi

The Netherlands delivers Earth observation instrument Tropomi

After a succesful building and development phase the Dutch Earth observation instrument Tropomi has been integrated with the Sentinel 5 Precursor satellite. The completion of the integration in the cleanroom of Airbus Defence and Space in Stevenage, Engeland, is a milestone in the European Earth observation mission, which will gather data globally on our climate and air quality. The results of many months with calibration tests confirm that the space instrument will deliver very accurate measurements of the Earth's atmosphere.        Read more (in dutch)
09-07-2015
student-lays-technology-foundation-for-balloon-mission-camera

Student lays technology foundation for balloon mission camera

Last week TU Delft student XuXiang Liu obtained his Msc degree in Electrical Engineering. XuXiang, who graduated with cum laude, was the very first student in Electrical Engineering who did his graduation project at SRON. At SRON he laid a solid technology foundation for the proposed cameras of the NASA balloon borne observatory GUSTO.                         More

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Summary

HIFI's superb spectral resolution coupled with its ability to observe thousands of molecular, atomic and ionic lines at submillimeter wavelengths make it the instrument of choice to address many of the key  questions in modern astrophysics related to the cyclic interaction of stars and the interstellar medium:
  1. HIFI will probe the physics, kinematics and energetics of star forming regions through their cooling lines, including H2O, the major coolant.
  2. HIFI will survey the molecular inventory of such diverse regions as shocked molecular clouds, dense Photon-Dominated Regions (PDRs), diffuse atomic clouds, Hot Cores and proto-planetary disks around newly formed stars, winds from dying stars and toroids interacting with AGN engines.
  3. HIFI is uniquely suited to search for low-lying ro-vibrational transitions of complex species such as PAHs and, thus, to investigate the origin and evolution of the molecular universe.
  4. HIFI can provide the out-gassing rate of comets through H2O rotational lines and determine the vertical distribution of H2O in the giant planets and on Mars.
  5. HIFI can measure the mass-loss history of stars which, rather than nuclear burning, regulates stellar evolution after the main sequence, and dominates the gas and dust mass balance of the ISM.
  6. HIFI will measure the FIR line spectrum of nearby galaxies as templates for distant, possibly primordial galaxies.

The main reason to build HIFI was because the above sketched science cannot be done from the ground, since atmospheric water lines block all radiation coming from space. On the right plots are given of the atmospheric transmission.

HIFI is optimised to address the astronomical key questions given above. All of these require high spectral resolving powers and sensitivity. Combining the high spectral resolving power of the radio heterodyne technique with quantum-noise limited detection from superconductor physics and state-of-the-art microwave technology, has made it possible to develop an instrument with a continuous frequency coverage from 480 to 1250 GHz in five bands, plus a sixth band providing coverage for 1410-1910 GHz at an unrivalled spectral resolution and ultimate sensitivity. This instrument is able to perform rapid and complecte spectral line surveys with resolving powers from 103 up to 107 (300 - 0.03 km/s) and deep line observations.

HIFI Band

1

2

3

4

5

6

Coverage (GHz)

480-
640

640-
800

800-
960

960-
1120

1120-
1250

1410-
1910

Half Power
Beamwidth
(arcsec)

39

30

25

21

19

13

Rec. Noise
(DSB) in K
Baseline values

110

145

175

210

370

800