www.sron.nl/122-hifi2/hifi.html

07-10-2014
recordaantal-bezoekers-sron-open-dag

Record number of visitors at SRON Open Day

The Open Day of SRON on Sunday, October 5, was a great success: a total of 1300 visitors came to the locations in Utrecht and Groningen. The visitors were very enthusiast and impressed by the many activities of SRON.          More
06-10-2014
athena-industry-day

Athena Industry Day

Athena - the next large X-ray mission of the European Space Agency (ESA)- will be fitted with detectors from SRON. On Friday 7 november the Athena Industry Day takes place. You can subscribe now.        Read more (in dutch)
01-10-2014
mysterious-cloud-on-titan-made-of-hydrogen-cyanide

Mysterious cloud on Titan made of hydrogen cyanide

    Since 2012, an enormous cloud is floating high above the South Pole of Titan, a large moon of Saturn. Astronomers have now discovered that this cloud consists of extremely toxic hydrogen cyanide ice. The ice has probably formed after a rapid cooling of the atmosphere. The results have this week been published in Nature.         More
30-09-2014
ruik-zie-en-hoor-het-heelal

Smell, see and hear the universe

Always wanted to know what space instruments look like and how they are made? Come to the Open Day of space research institute SRON in Utrecht or Groningen on October 5 and immerse yourself in the world of space research. SRON can be visited between 12.00 and 17.00 hr.            Read more (in dutch)
09-09-2014
first-dutch-contribution-to-giant-telescope-e-elt-passes-all-tests

First Dutch contribution to giant telescope E-ELT passes all tests

The first Dutch contribution to the planned European Extremely Large Telescope (E-ELT) has passed the tests succesfully. It concerns the 'chopper', a very versatile little mirror which has been developed by a consortium of Dutch universities, technological institutes and industry. The high tech mirror is an essential part of METIS, the mid-infrared camera annex spectrometer of the giant telecope.        Read more (in dutch)

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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