The primary aims of my research are investigation of the spiral
structure of the Milky Way Galaxy, analysis of the stellar content of
star clusters and galaxy nuclei, and the discovery and description of
peculiar and variable stars.
Most astronomers use, in some way, the
fundamental information provided by the classification of stellar
spectra. Spectral classification is an extremely powerful tool for
describing the important astrophysical characteristics of stars and
stellar systems. The MK System, developed by Morgan and Keenan, is
virtually the only one used today, and Toronto is a major centre for
research in this field.
The general thrust of my work has been the development and maintenance
of a centre in the field of MK spectral classification at the David
Dunlap Observatory (DDO). To this end, 6 classification-dispersion
(100 Ångström/mm) spectrographs
have been built and placed at various
facilities around the world, including DDO, the recommissioned El
Leoncito (Argentina) former 60-cm
UTSO (Chile)
telescope, and the
Mexican National Observatory in Baja California. These spectrographs
are being used for taking spectra of many types of stars for
fundamental work on the classification system itself and for surveys
using the system.
Research initiatives now essentially completed by me and my
associates include
-
using the CCD spectrograph in Chile for carefully translating the MK
System of stellar classification from the photographic to the digital
dialect
-
developing and testing computerized pattern-recognition techniques for
automated classification of large numbers of stars, with M. Kurtz
(Center for Astrophysics, Harvard) and J. LaSala (University of
Southern Maine)
Research initiatives actively pursued by me and my associates
include
-
extending the MK classification process to the ultraviolet, red, and
infrared wavelength regions
-
surveying the nearby stars ("NStars") closer than 47 parsecs and of
spectral types earlier than M0
-
defining a hierarchy of standards, in a framework comprising anchor
points, primary standards, secondary standards, and peculiar-star
prototypes
Maintenance and refinement of the MK System is an ongoing process for
a few, needed to keep the system useful for others. Many of the
pitfalls of dealing with digital data have been discovered and
recently accommodated within the system, with the result that the
classification process is fundamentally and dramatically improved. Our
emphasis has now shifted to data and results: I and my associates are
working on several papers using reconnaissance techniques for
discovery and investigation of interesting peculiar stars.
To create a permanent all-presentations record of the 1983 University
of Toronto workshop on stellar classification (the last astronomical
conference attended by both W.W. Morgan and P.C. Keenan), I
edited The MK Process and Stellar Classification. This volume,
published by the David Dunlap Observatory and available on request to
me for the price of postage and handling, is still finding new
readers. Thanks to the quality of many of its papers, it has achieved
a much longer lifespan than is typical for conference proceedings.
Because I am one of the principal workers in the field of MK
spectral classification, I often get requests for MK types from my own
spectra, or for information on types in the literature. I have a very
extensive collection of stellar spectra (comprising photographic and
digital spectra of about 10,000 stars, of which 5,000 have been
published) as well as a catalogue of MK types. This computerized
catalogue, representing a large investment of time, does not appear in
my list of publications. However, the responses to the requests, and
the catalogue data, are useful in many subfields in astronomy. New
stars are being added continually. Indeed, current observations are
essential for the maintenance of the reference frame and the database.
For example, I have supplied types for all stars brighter than
apparent B magnitude 4.5 in the Michigan Spectral Catalogue (the
2-dimensional successor to the HD Catalogue).
My major collaborations during the past two decades have been with
Chris Corbally and Richard Gray.
Selected Articles
Garrison, R. F.
"Comments
on the Method of
Spectroscopic Parallax."
Publications of the
Astronomical Society of the Pacific, 100 (1988): 1036.
Garrison, R. F. "The Use and Abuse of Standard Stars."
In Calibration of
Fundamental Stellar Quantities,
International Astronomical Union Symposium 111 (1985): 17.
Corbally, C.J., and R.F. Garrison. "A Survey for G-Dwarf Stars towards
the South Galactic Pole."
Astronomical Journal, 95 (1988): 739, 745.
Gray, R.O., and R.F. Garrison.
"The Early F-Type Stars:
Refined Classification,
Confrontation with Strömgren Photometry,
and the Effects of Rotation."
Astrophysical Journal Supplement, 69 (1989): 301.
Gray, R.O., and R.F. Garrison.
"The Late A-Type Stars:
Refined Classification,
Confrontation with Strömgren Photometry,
and the Effects of Rotation."
Astrophysical Journal Supplement, 70 (1989): 623.
Garrison, R.F., and B. Beattie.
"The University of Toronto Southern Observatory:
A Discussion of Productivity 1979-1986."
The Journal of the Royal Astronomical Society of Canada, 84 (1990): 246.
Garrison, R.F.
"The Hertzsprung-Russell Diagram."
In The Astronomy and Astrophysics Encyclopedia,
edited by S. Maran,
736-39.
New York: Van Nostrand Reinhold, 1992.
Garrison, R.F.
"The Process of Discovery:
Supernovae, Comets, and Extraterrestrial Life."
Vistas in Astronomy, 35 (1992): 73.
Spence, I., and R.F. Garrison.
"A Remarkable Scatterplot."
The American Statistician, 47 (1993): 12.
Garrison, R.F.,
K.W. Kamper,
A. Ridder, and
Ian Shelton.
"A New CCD for the
Classification Spectrograph
at the University of Toronto Southern Observatory
(UTSO)
in Chile."
The Journal of the Royal Astronomical Society of Canada, 87 (1993): 151.
Garrison, R.F. and C.J. Corbally.
"The Spectra of G Dwarf Stars towards the
Galactic Poles."
Astronomical Journal, 106 (1993): 2301.
Evans, N.R.,
J.H. Jiang,
R.F. Garrison,
R.O. Gray,
T.G. Barnes,
and M.L. Frueh.
"HR 9053: A Lightly Reddened G Supergiant."
The Journal of the Royal Astronomical Society of Canada, 88 (1994): 155.
Garrison, R.F., and R.O. Gray.
"The Late B-Type Stars:
Refined Classification,
Confrontation with Strömgren Photometry,
and the Effects of Rotation."
Astronomical Journal , 107 (1994): 1556.
Kurtz, D.W.,
R.F. Garrison,
C. Koen,
G.F. Hofmann,
and N.B. Viranna.
"Metallicism and Pulsation:
The Discovery of Large-Amplitude delta Scuti Pulsation
in a High-Metallicity rho Puppis Star, HD 40765."
Monthly Notices of the Royal Astronomical Society, 276 (1995): 199.
Rucinski, Slavek,
R.F. Garrison,
and Boyd Duffee.
"U-Filter Photometry of AB Doradus."
International Astronomical Union
Information Bulletin on Variable Stars, 4156 (1995): 1.
Garrison, R.F.
"William Wilson Morgan: (1906-1994)."
Publications of the
Astronomical Society of the Pacific, 107 (1995):
507.
Garrison, R.F.
"Spectroscopic Monitoring of HD 49798 : A Hot Subdwarf
with an X-ray Pulsating Companion."
The Journal of the Royal Astronomical Society of Canada, 90 (1996): 319.
Fernie, J. Donald,
Max Faúndez-Abans,
Barry F. Madore,
Mart de Groot,
Richard A. Crowe,
Robert F. Garrison,
and
Jaymie M. Matthews.
"Extracts from the Diaries of the University of Toronto Southern
Observatory. IV. Pot-Pourri."
The Journal of the Royal Astronomical Society of Canada, 90 (1996): 270.
Garrison, Robert F.
"Personalities of Mira Variables as Revealed by
Their Spectra - Verdict: Bizarre!"
Journal of the American Association of Variable Star Observers, 25 (1997): 70.
Garrison, Robert F.
"On the Difficulty of Observing the Sun as a Star."
In Solar Analogs : Characteristics and Optimum Candidates,
edited by Jeffrey C. Hall. Flagstaff, Arizona: Lowell Observatory, 1998.
Wiegert, Paul, and R.F. Garrison.
"A Search for Helium Spectrum Variables."
The Journal of the Royal Astronomical Society of Canada, 92 (1998):
134.
Garrison, R.F.
"Spectroscopic Monitoring of HD 49798: A Hot Subdwarf
with an X-Ray Pulsating Companion."
Proceedings of the Astronomical
Society of the Pacific, 110 (1998):
1315.
Corbally, C.J.,
R.F. Garrison,
W. Rueger,
and C.R. Stagg.
"G-Dwarf Stars in the Galactic Halo."
Astrophysics and Space Science, 265 (1999): 187.
Reprinted in
Galaxy Evolution: Connecting the Distant Universe with the Local Fossil
Record. Proceedings of a Colloquium on This Subject Held at the
Observatoire de Paris-Meudon from 21-25 September 1998,
edited by Monique Spite (Dordrecht: Kluwer, 1999).
Garrison, R.F.
"Spectral Types for Nearby Stars:
What Can We Learn about Our Neighbourhood?"
In Nearby Stars (NStars) Workshop
Proceedings, edited by Dana E. Backman,
Shirley J. Burg, and Todd J. Henry. Moffet Field,
California: NASA Ames Research Center, 2001.
Nearly complete proceedings of this 1999 workshop,
with some post-1999 updates, are available also at
http://nstars.arc.nasa.gov/w_proceedings.cfm.
Garrison, Robert F.
"President's Corner."
A bimonthly column in
The Journal of the Royal Astronomical Society of Canada,
from 2000 August to 2002 June.
Koktay, Tuba, and R.F. Garrison.
"Spectral Classification
of Carbon-Peculiar G Stars."
International Astronomical Union Symposium 177 (2000): 141.
Wing, Robert F., Robert F. Garrison,
and Tuba Koktay.
"Temperatures of Peculiar G-Type Stars from Narrow-Band Near-Infrared
Photometry."
International Astronomical Union Symposium 177 (2000): 588.
Garrison, R.F. "Classification of Stellar Spectra." In
Encyclopedia of Astronomy and Astrophysics, edited by
Paul Murdin, I.351-357. Philadelphia: Institute of Physics, Nature
Publishing Group, 2001. This article is one of the 700 "Main"-category
articles in the four-volume encyclopedia.
Garrison, R.F. "The Brightest Stars." In Observer's
Handbook, edited by R. Bishop. Toronto: The Royal Astronomical
Society of Canada. Article updated annually.
Garrison, R.F.
"Les Étoiles plus brillantes."
In Annuaire astronomique, le ciel,
edited by J.P. Urbain.
Montréal:
Société d'astronomie de Montréal.
Article updated annually.
Garrison, R.F.
"Spectrophotometric and Photometric Catalogues:
Standard Stars and Solar Analogs."
Joint European and National Astronomical Meeting for 2000
(2000 June 5-8), St. Petersburg.
Forthcoming in the publications of
Pulkovo Observatory.
Garrison, R.F.
"The MK Process: A Vision for the Future."
In A Festschrift for R.F. Garrison:
Probing the Personalities of Stars and Galaxies,
edited by C.J. Corbally and R.O. Gray.
Forthcoming at L. Davis Press.
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