A Caltech Library Service

The Molecular Spectrum of Sunspots


Webber, John Clinton (1970) The Molecular Spectrum of Sunspots. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/FKJP-0C31.


The sunspot spectrum shows many molecular lines, of which some have been identified. These lines are formed farther out in the sunspot atmosphere than the atomic lines or the continuum, and are thus useful for probing the outer layers. Photographic spectrograms were obtained for three different sunspots under carefully selected seeing conditions, showing molecular absorption lines due to MgH, CaH, and TiO. Analysis led to estimates of the effective rotational temperatures of each; in the case of CaH, no definite conclusions could be drawn. Predicted rotational temperatures and observational f-values were calculated on the basis of model umbral atmospheres due to several authors. A new model was derived from the molecular lines measured here, and shown to differ widely from previous models. The usefulness of photographic spectra for this purpose is seriously questioned, and suggestions are made for new observations.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:(Astronomy, Physics and English)
Degree Grantor:California Institute of Technology
Division:Physics, Mathematics and Astronomy
Major Option:Astronomy
Minor Option:English
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Zirin, Harold
Group:Astronomy Department
Thesis Committee:
  • Unknown, Unknown
Defense Date:2 September 1969
Record Number:CaltechETD:etd-05012008-151521
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:1568
Deposited By: Imported from ETD-db
Deposited On:16 May 2008
Last Modified:22 May 2024 18:42

Thesis Files

PDF (Webber_jc_1970.pdf) - Final Version
See Usage Policy.


Repository Staff Only: item control page