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[Activities of Harvard College Observatory]With support from this grant, we have: 1) Developed techniques for improving wavelengths and f-values for singly and doubly charged ions of the iron group and have improved the accuracy of Fe III wavelengths by an order of magnitude. New Fe II f-values have also resulted from this work. 2) Measured line oscillator strengths and photoabsorption cross sections for UV molecular spectral feature that have been, or could be, used for searches for and detection of molecules in diffuse and translucent interstellar clouds and for determination of molecular column densities there. In addition, we have determined other molecular parameters -- line assignments, wavelengths, and line widths -- that are essential for theoretical descriptions of the abundance, fractionation, and excitation of interstellar molecules and for comparison of predictions with observations. 3) Measured A-values for spin-changing and other weak lines in low-Z ions. When A-values are available, these spectral features are useful for astrophysical plasma density and temperature diagnostics. Such lines are also used in interstellar abundance determinations in cases where the stronger allowed lines are saturated in astronomical spectra. 4) Taken an activist approach to ensuring that, (i), astronomers have ready access to our data, and, (ii), avenues of communication between data users and producers are strengthened.
Document ID
20030067745
Acquisition Source
Headquarters
Document Type
Contractor or Grantee Report
Authors
Dalgarno, A.
(Harvard Coll. Observatory Cambridge, MA, United States)
Smith, Peter L.
(Harvard Coll. Observatory Cambridge, MA, United States)
Stark, G.
(Harvard Coll. Observatory Cambridge, MA, United States)
Yoshino, K.
(Harvard Coll. Observatory Cambridge, MA, United States)
Date Acquired
August 21, 2013
Publication Date
January 1, 2002
Subject Category
Astrophysics
Funding Number(s)
CONTRACT_GRANT: NAG5-4348
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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