Advertisement

Experimental Astronomy

, Volume 37, Issue 2, pp 357–367 | Cite as

Herschel SPIRE FTS spectral mapping calibration

  • Dominique Benielli
  • Edward Polehampton
  • Rosalind Hopwood
  • Ana Belén Griñón Marín
  • Trevor Fulton
  • Peter Imhof
  • Tanya Lim
  • Nanyao Lu
  • Gibion Makiwa
  • Nicola Marchili
  • David Naylor
  • Locke Spencer
  • Bruce Swinyard
  • Ivan Valtchanov
  • Matthijs van der Wiel
Original Article

Abstract

The Herschel SPIRE Fourier transform spectrometer (FTS) performs spectral imaging in the 447–1546 GHz band. It can observe in three spatial sampling modes: sparse mode, with a single pointing on sky, or intermediate or full modes with 1 and 1/2 beam spacing, respectively. In this paper, we investigate the uncertainty and repeatability for fully sampled FTS mapping observations. The repeatability is characterised using nine observations of the Orion Bar. Metrics are derived based on the ratio of the measured intensity in each observation compared to that in the combined spectral cube from all observations. The mean relative deviation is determined to be within 2 %, and the pixel-by-pixel scatter is ∼ 7 %. The scatter increases towards the edges of the maps. The uncertainty in the frequency scale is also studied, and the spread in the line centre velocity across the maps is found to be ∼ 15 km s − 1. Other causes of uncertainty are also discussed including the effect of pointing and the additive uncertainty in the continuum.

Keywords

SPIRE FTS Calibration Repeatability Error 

Notes

Acknowledgments

Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. SPIRE has been developed by a consortium of institutes led by Cardiff University (UK) and including Univ. Lethbridge (Canada); NAOC (China); CEA, LAM (France); IFSI, Univ. Padua (Italy); IAC (Spain); Stockholm Observatory (Sweden); Imperial College London, RAL, UCL-MSSL, UKATC, Univ. Sussex (UK); and Caltech, JPL, NHSC, Univ. Colorado (USA). This development has been supported by national funding agencies: CSA (Canada); NAOC (China); CEA, CNES, CNRS (France); ASI (Italy); MCINN (Spain); SNSB (Sweden); STFC (UK); and NASA (USA).

References

  1. 1.
    Abergel, A., Arab, H., Compiègne, M., et al.: Evolution of interstellar dust with Herschel. First results in the photodissociation regions of NGC 7023. A&A 518, L96 (2010)ADSCrossRefGoogle Scholar
  2. 2.
    Buckle, J.V., Davis, C.J., Di Francesco, J., et al.: The JCMT legacy survey of the gould belt: mapping 13CO and C18O in Orion A. MNRAS 422, 521 (2012)ADSCrossRefGoogle Scholar
  3. 3.
    Davis, S.P., Abrams, M.C., Brault, J.W.: Fourier Transform Spectroscopy, p. 149. Academic, San Diego (2001)Google Scholar
  4. 4.
    Griffin, M.J., Abergel, A., Abreu, A., et al.: The Herschel-SPIRE instrument and its in-flight performance. A&A 518, L3 (2010)ADSCrossRefGoogle Scholar
  5. 5.
    Habart, E., Dartois, E., Abergel, A., et al.: SPIRE spectroscopy of the prototypical Orion Bar photodissociation region. A&A 518, L116 (2010)ADSCrossRefGoogle Scholar
  6. 6.
    Lis, D.C., Schilke, P.: Dense molecular clumps in the orion bar photon-dominated region. ApJ 597, L145 (2003)ADSCrossRefGoogle Scholar
  7. 7.
    Makiwa, G., Naylor, D., Ferlet, M., et al.: Beam profile for the Herschel-SPIRE Fourier transform spectrometer. Appl. Opt. 52, 16 (2013)CrossRefGoogle Scholar
  8. 8.
    Naylor, D.A., Baluteau, J.-P., Barlow, M.J., et al.: In-orbit performance of the Herschel/SPIRE imaging fourier transform spectrometer. In: Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 7731 (2010)Google Scholar
  9. 9.
    Ott, S.: The Herschel data processing system - HIPE and pipelines - up and running since the start of the mission. In: ASP Conference Series, vol. 434 (ADASS XVIII), p. 139 (2010)Google Scholar
  10. 10.
    Pilbratt, G.L., Riedinger, J.R., Passvogel, T., et al.: Herschel space observatory. An ESA facility for far-infrared and submillimetre astronomy. A&A 518, L1 (2010)ADSCrossRefGoogle Scholar
  11. 11.
    Sánchez-Portal M., et al.: this issue (2013)Google Scholar
  12. 12.
    Spencer, L.D., Naylor, D.A., Swinyard, B.M.: Performance evaluation of the Herschel/SPIRE imaging Fourier transform spectrometer through ground-based measurements. Meas. Sci. Technol. 21, 065601 (2010)ADSCrossRefGoogle Scholar
  13. 13.
    Swinyard B., Polehampton E., Hopwood R., et al.: Calibration of the Herschel SPIRE fourier transform spectrometer. MNRAS, submittedGoogle Scholar
  14. 14.
    SPIRE observers manual, version 2.4, available from the Herschel Science Centre (2011)Google Scholar
  15. 15.
    Wilson, T.L., Muders, D., Kramer, C., et al.: Submillimeter CO line emission from orion. ApJ 557, 240 (2001)ADSCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  • Dominique Benielli
    • 1
  • Edward Polehampton
    • 2
    • 3
  • Rosalind Hopwood
    • 4
  • Ana Belén Griñón Marín
    • 2
  • Trevor Fulton
    • 3
    • 5
  • Peter Imhof
    • 3
    • 5
  • Tanya Lim
    • 2
  • Nanyao Lu
    • 6
  • Gibion Makiwa
    • 3
  • Nicola Marchili
    • 7
  • David Naylor
    • 3
  • Locke Spencer
    • 3
  • Bruce Swinyard
    • 2
  • Ivan Valtchanov
    • 8
  • Matthijs van der Wiel
    • 3
  1. 1.Aix Marseille Université, CNRS, LAM (Laboratoire d’Astrophysique de Marseille) UMR 7326MarseilleFrance
  2. 2.RAL Space, Rutherford Appleton LaboratoryDidcotUK
  3. 3.Institute for Space Imaging Science, Department of Physics and AstronomyUniversity of LethbridgeLethbridgeCanada
  4. 4.Physics DepartmentImperial College LondonLondonUK
  5. 5.Bluesky SpectroscopyLethbridgeCanada
  6. 6.NHSC/IPACPasadenaUSA
  7. 7.Dipartimento di Fisica e AstronomiaUniversità di PadovaPadovaItaly
  8. 8.Herschel Science Centre, ESACVillanueva de la CañadaSpain

Personalised recommendations