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

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)
27-08-2014
thermonuclear-x-ray-bursts-on-neutron-stars-set-speed-record

Thermonuclear X-ray bursts on neutron stars set speed record

A new study of thermonuclear X-ray bursts on neutron stars reveals that, on very rare occasions, shells can be expelled at relativistic speeds - up to 30% of the speed of light. These velocities are the highest ever measured for a cosmic thermonuclear event, including novae and thermonuclear supernovae. This phenomenon, discovered in only 0.1 second worth of data in 40 years of space-based X-ray astronomy, sheds new light on how nuclear flames spread over surfaces of neutron stars. The research results have been published in Astronomy & Astrophysics.         More
25-07-2014
chandra-and-letg-celebrate-15th-anniversary

Chandra and LETG celebrate 15th anniversary

Fifteen years ago, NASA's Chandra X-ray Observatory was launched into space aboard the Space Shuttle Columbia. Since its deployment on July 23, 1999, Chandra has helped revolutionize our understanding of the universe through its unrivalled X-ray vision. SRON provided the Low Energy Transmission Grating (LETG) for Chandra in collaboration with the Max Planck Institut für Extraterrestrische Physik (MPE) in Garching (near München). With this grating, astronomers were able to take a closer look at high energetic processes around astronomical objects, such as black holes, for the very first time.         More
09-07-2014
sron-annual-magazine-2012-2013

SRON annual magazine 2012-2013

Welcome to the first digital annual magazine from SRON Netherlands Institute for Space Research. In words and images this magazine provides an overview of the most important developments, scientific highlights, technological breakthroughs and new instruments in 2012 and 2013.         More
02-07-2014
jelle-kaastra-appointed-professor-at-leiden-university

Jelle Kaastra appointed honorary professor at Leiden University

SRON-researcher Jelle Kaastra has been appointed honorary professor of High Energy Astrophysics at Leiden University. The appointment is per 1 April 2014.         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