Concept Study of the Heterodyne Spectroscopy Instrument (HSI) for the proposed Far-IR Spectroscopy Space Telescope (FIRSST)
Artikel i vetenskaplig tidskrift, 2026

The Heterodyne Spectroscopy Instrument (HSI) is a focal plane array receiver (FPA) for the Far-IR Spectroscopy Space Telescope (FIRSST), a proposal submitted to NASA's APEX call. Though FIRSST was not selected for further study, the receiver design allowed us to quantitatively demonstrate that small (few to few tens of pixels) heterodyne FPAs are now feasible for space missions, can be built with high TRL components, are reliable and fit within the mass/volume/power constraints of medium to large missions. The design also identified the challenges and critical design considerations, in particular that great care needs to be taken to minimize the cryogenic heat load of the cryogenic IF amplifiers and to keep the power consumption of the spectrometer backends low. The HSI was designed primarily to study the trail of water from the Interstellar Medium (ISM) to planets and to observe the important low-lying transitions of water and its isotopes between 500 and 2000 GHz undetectable from the ground due to Earth's atmosphere. HSI has a spectral resolving power of up to 107 (0.03 km/s), ideal for kinematic studies or line tomography. HSI has six 5-pixel-arrays covering 3 frequency bands and 2 linear polarizations. The concept study showed that heterodyne array receivers such as HSI can be built today even for fast missions and that they are powerful and versatile instruments, with low-risk technology capable of opening up the THz sky at very high spectral resolving power for new discoveries.

heterodyne receivers

Far-IR space instruments

THz astronomy

Heterodyne instruments

array receivers

THz detectors

Författare

M.C. Wiedner

Université Paris Descartes

A. M. Baryshev

Rijksuniversiteit Groningen

P. K. Grimes

Harvard-Smithsonian Center for Astrophysics

Victor Belitsky

Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium

Vincent Desmaris

Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium

Y. Delorme

Université Paris Descartes

J. D. Gallego

Observatorio de Yebes (IGN)

Cristina García-Miró

Observatorio de Yebes (IGN)

U. Gorti

SETI Institute

P. Hartogh

Max-Planck-Gesellschaft

N. Honingh

Universität zu Köln

Benjamin Klein

Max-Planck-Gesellschaft

Fachhochschule Bonn-Rhein-Sieg

J. M. Krieg

Université Paris Descartes

G. J. Melnick

Harvard-Smithsonian Center for Astrophysics

Sebastiano Ligori

Istituto nazionale di astrofisica (INAF)

B. K. Tan

University of Oxford

B. Thomas

RPG Radiometer Physics GmbH

Europeiska rymdorganisationen (ESA)

V. Tolls

Harvard-Smithsonian Center for Astrophysics

J. Treuttel

Université Paris Descartes

Jérôme Valentin

Observatoire de Paris

D. L. Clements

Imperial College London

R. Blundell

Harvard-Smithsonian Center for Astrophysics

A. Cooray

University of California

M. Macgregor

Johns Hopkins University

Ronald J. Vervack

Johns Hopkins University

IEEE Transactions on Terahertz Science and Technology

2156-342X (ISSN) 21563446 (eISSN)

Vol. In Press

Ämneskategorier (SSIF 2025)

Annan elektroteknik och elektronik

Astronomi, astrofysik och kosmologi

DOI

10.1109/TTHZ.2026.3671953

Mer information

Senast uppdaterat

2026-03-19