Skip to main content
SpringerLink
Log in

On the Photometric Accuracy of RHESSI Imaging and Spectrosocopy

  • Published:
Solar Physics Aims and scope Submit manuscript

Abstract

We compare the photometric accuracy of spectra and images in flares observed with the Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) spacecraft. We test the accuracy of the photometry by comparing the photon fluxes obtained in different energy ranges from the spectral-fitting software SPEX with those fluxes contained in the images reconstructed with the Clean, MEM, MEM-Vis, Pixon, and Forward-fit algorithms. We quantify also the background fluxes, the fidelity of source geometries, and spatial spectra reconstructed with the five image reconstruction algorithms. We investigate the effects of grid selection, pixel size, field of view, and time intervals on the quality of image reconstruction. The detailed parameters and statistics are provided in an accompanying CD-ROM and web page. We find that Forward-fit, Pixon, and Clean have a robust convergence behavior and a photometric accuracy in the order of a few percent, while MEM does not converge optimally for large degrees of freedom (for large field of view and/or small pixel sizes), and MEM-Vis suffers in the case of time-variable sources. This comparative study documents the current status of the RHESSI spectral and imaging software, one year after launch.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Alexander, D. and Metcalf, T. R.: 1997, Astrophys. J. 489, 442.

    Article  ADS  Google Scholar 

  • Aschwanden, M. J., Brown, J. C., and Kontar, E. P.: 2002, Solar Phys. 210, 383.

    ADS  Google Scholar 

  • Aschwanden, M. J., Schmahl, E., and RHESSI Team, 2002, Solar Phys. 210, 193.

    ADS  Google Scholar 

  • Brown, J. C., Aschwanden, M. J., and Kontar, E. P.: 2002, Solar Phys. 210, 373.

    Article  ADS  Google Scholar 

  • Hurford, G. J., Schmahl, E. J., Schwartz, R. A., Conway, A. J., Aschwanden, M. J., Csillaghy, A., Dennis, B. R., Johns-Krull, C., Krucker, S., Lin, R. P., McTiernan, J., Metcalf, T. R., Sato, J., and Smith, D. M.: 2002, Solar Phys. 210, 61.

    ADS  Google Scholar 

  • Kontar, E. P., Brown, J. C., and McArthur, G. K.: 2002, Solar Phys. 210, 419.

    Article  ADS  Google Scholar 

  • Krucker, S. and Lin, R. P.: 2002, Solar Phys. 210, 229.

    ADS  Google Scholar 

  • Lin, R. P. and 65 co-authors: 2002, Solar Phys. 210, 3.

    ADS  MATH  Google Scholar 

  • Metcalf, T. R., Hudson, H. S., Kosugi, T., Puetter, R. C., and Pina, R. K.: 1996, Astrophys. J. 466, 585.

    Article  ADS  Google Scholar 

  • Smith, D. M. et al.: 2002, Solar Phys. 210, 33.

    Article  ADS  Google Scholar 

  • Schmahl, E. J. and Hurford, G. J.: 2003, Adv. Space Res. (COSPAR Proc.), in press.

  • Schwartz, R. A., Csillaghy, A., Tolbert, A. K., Hurford, G. J., McTiernan, J., and Zarro, D.: 2002, Solar Phys. 210, 165.

    Article  ADS  Google Scholar 

  • Sui, L., Holman, G. D., Dennis, B. R., Krucker, S., Schwartz, R. A., and Tolbert, K.: 2002, Solar Phys. 210, 245.

    Article  ADS  Google Scholar 

  • Vilmer, N., Krucker, S., Lin, R. P., and RHESSI Team: 2002, Solar Phys. 210, 261.

    Article  ADS  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Lockheed Martin Advanced Technology Center, Solar & Astrophysics Laboratory, Dept. L9-41, Bldg.252, 3251 Hanover, St., Palo Alto, CA , 94304, U.S.A

    Markus J. Aschwanden & Thomas R. Metcalf

  2. Space Sciences Laboratory, University of California at Berkeley, Berkeley, CA , 94720-7450, U.S.A

    Säm Krucker & G.J. Hurford

  3. Dept. of Physics, Montana State University, Bozeman, MO , 59717, U.S.A

    Jun Sato

  4. Dept. Physics and Astronomy, The Open University, Milton, Keynes, MK7 6AA, U.K

    Andrew J. Conway

  5. Solar & Astrophysics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD~, 20770, U.S.A

    Edward J. Schmahl

  6. Astronomy Dept, University of Maryland, College Park, MD~, 20742, U.S.A

    Edward J. Schmahl

Authors
  1. Markus J. Aschwanden
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Thomas R. Metcalf
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Säm Krucker
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Jun Sato
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Andrew J. Conway
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. G.J. Hurford
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Edward J. Schmahl
    View author publications

    You can also search for this author in PubMed Google Scholar

Electronic supplementary material

Rights and permissions

Reprints and permissions

About this article

Cite this article

Aschwanden, M.J., Metcalf, T.R., Krucker, S. et al. On the Photometric Accuracy of RHESSI Imaging and Spectrosocopy. Sol Phys 219, 149–157 (2004). https://doi.org/10.1023/B:SOLA.0000021801.83038.aa

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1023/B:SOLA.0000021801.83038.aa

Keywords

Search

Navigation