Spectral Line Selection for HMI

Bibcode
2006ASPC..358..193N
Norton, A. A.; Pietarila Graham, J. D.; Ulrich, R. K.; Schou, J.; Tomczyk, S.; Liu, Y.; Lites, B. W.; López Ariste, A.; Bush, R. I.; Socas-Navarro, H.; Scherrer, P. H.
Bibliographical reference

Solar Polarization 4, ASP Conference Series, Vol. 358, Proceedings of the conference held 19-23 September, 2005, in Boulder, Colorado, USA. Edited by R. Casini and B. W. Lites, p.193

Advertised on:
12
2006
Number of authors
11
IAC number of authors
0
Citations
2
Refereed citations
2
Description
We present information on two spectral lines, Fe I 6173 Å and Ni I 6768 Å, that were candidates for use in the Helioseismic and Magnetic Imager (HMI) instrument. Both Fe I and Ni I profiles have clean continuum and no blends that threaten performance. The higher Landé factor of Fe I means its operational velocity range in regions of strong magnetic field is smaller than for Ne I. Fe I performs better than Ni I for vector magnetic field retrieval. Inversion results show that Fe I consistently determines field strength and flux more accurately than the Ni I line. Inversions show inclination and azimuthal errors are recovered to ≈2° above 600 Mx/cm2 for Fe I and above 1000 Mx/cm2 for Ni I. The Fe I line was recommended, and ultimately chosen, for use in HMI.
Type
Non-refereed

It may interest you

  • Non-refereed
    ROSALIA: ROman Sky Analyst for Low surface brightness Imaging & Astronomy
    Diffuse emission in the outskirts of galaxies, such as stellar tidal streams, galaxy stellar halos and intracluster light, provides important constraints on the structure and evolution of the Universe. However, such low surface brightness diffuse emission can be up to thousands of times dimmer (>29 AB mag/[square arcseconds]) than the sky
    Laine, Seppo et al.

    Advertised on:

    6
    2024
    Bibcode
    2024AAS...24412902L
    Citations
    0
  • Non-refereed
    A Systematic Search for and Characterization of White Dwarf Binaries Across the H-R Diagram
    White dwarfs (WDs) are the endpoint of evolution for 97% of stars. Most of these stars are in multiple systems, and a significant fraction of those are compact enough to exchange mass, altering the structures and subsequent evolution of both stars. The physical mechanisms that facilitate these mass exchanges include common envelope evolution, Roche
    Anguiano, Borja et al.

    Advertised on:

    6
    2024
    Bibcode
    2024AAS...24410807A
    Citations
    0
  • Non-refereed
    Deep HST Imaging Favors the Bulgeless Edge-on Galaxy Explanation for the Hypothetical Stellar Wake Created by a Runaway Supermassive Black Hole
    A long linear structure recently discovered could be the stellar wake produced by the passage of a runaway supermassive black hole (SMBH) or, alternatively, a bulgeless edge-on galaxy. We report on new very deep Hubble Space Telescope imaging that seems to be in tension with the SMBH runaway scenario but is consistent with the bulgeless edge-on
    Montes, Mireia et al.

    Advertised on:

    6
    2024
    Bibcode
    2024RNAAS...8..150M
    Citations
    0