Research Interests

• Polarimetry of circumstellar disks
  
• Rapidly rotating hot stars: geometry, variability, and physical conditions of their circumstellar envelopes
• Herbig Ae/Be pre-main sequence stars: circumstellar geometry & disk formation, and relation to proto-planetary systems
• Observational techniques to deduce the nature of circumstellar envelopes; multi-wavelength astronomy
• Observational signatures of variability in winds from massive stars; mass-loss rates due to stellar winds

• Ph.D. Astrophysics, May 1989, University of Colorado, Boulder (Thesis Advisor: Prof. Theodore P. Snow)
• M.S. Astrophysics, Dec 1984, University of Colorado, Boulder
• B.S. Physics, May 1979, University of North Carolina, Chapel Hill

August 2003 - present:
Professor of Astronomy, Ritter Astrophysical Research Center, Department of Physics & Astronomy, University of Toledo, Toledo, OH 43606-3390

August 2000 - August 2003:
Associate Professor of Astronomy, Ritter Astrophysical Research Center, Department of Physics & Astronomy, University of Toledo, Toledo, OH 43606-3390

September 1996 - August 2000:
Assistant Professor of Astronomy, Ritter Astrophysical Research Center, Department of Physics & Astronomy, University of Toledo, Toledo, OH 43606-3390

July 1993 - September 1996:
Associate Scientist, Space Astronomy Laboratory and Department of Astronomy, University of Wisconsin, Madison WI 53706-1390

February 1989 - June 1993:
Assistant Scientist, Space Astronomy Laboratory and Department of Astronomy, University of Wisconsin, Madison WI 53706-1390

June 1983 - February 1989:
Graduate Research Assistant, Center for Astrophysics & Space Astronomy, University of Colorado, Boulder CO 80309

January - December 1986:
Instructor, Astronomy Classes, Front Range Community College, Westminster, CO 80020

January - May 1985; August 1982 - May 1983:
Graduate Teaching Assistant, Department of Astrophysical, Planetary, & Atmospheric Sciences, University of Colorado, Boulder CO 80309

July 1979 - August 1982:
Engineer, Martin Marietta Denver Aerospace, Denver, CO 80201

Brief Summary of Previous Research (incomplete list)

(For a list of publications, see my Bibliography)

• Development of techniques for using spectropolarimetric diagnostics to determine physical characteristics (temperature, density, matter distribution) of circumstellar disks and envelopes
  
• First ultraviolet spectropolarimetry of Be stars (with the Wisconsin Ultraviolet Photo-Polarimeter Experiment - WUPPE); discovered significant differences from theoretical predictions; found that gravity darkening effects alone cannot explain results; suggested that line blanketing by Fe in circumstellar disk may explain differences; used Fe line depolarization to estimate disk temperatures

• Combined optical interferometry and spectropolarimetry to investigate Be star circumstellar envelopes; found that combined data strongly favors very thin disks rather than ellipsoidal envelopes; developed techniques to use modeling to determine disk opening angle and density from observations

• First spectropolarimetric study of a neon nova (Nova Cyg 1992); found evidence from continuum polarization of asymmetries in the ejecta - later confirmed by independent radio observations

• Optical spectropolarimetric survey of northern Be stars; found evidence for polarimetric variability; discovered depolarization effects across optical Fe lines in Zeta Tauri, suggesting that Fe is located outside scattering region but within disk; found evidence for correlations of wind line profile variability, photometric variability, and polarimetric changes in Pi Aqr, suggesting connection between wind & disk

• Extensive survey of UV spectra of Be and normal B stars, including Be stars with strong IR excesses; found evidence that superionized regions in circumstellar envelopes of Be stars may be confined to low latitudes; found that excess C IV absorption in Be stars over normal B stars was primarily due to discrete absorption components; developed technique to derive inclination angles of Be stars using IR photometry and optical polarization measurements

• Collaborated on simultaneous multi-spectral observations of Be, WR, and hot supergiants, including the first radio detection of Be star Psi Persei

• Participated in optical and UV spectropolarimetric studies of Be, WR, supergiant, B[e], and Herbig Ae/Be stars, as well as novae and supernovae; results included: evidence for bipolar flows and mass infall in HD 45677, suggesting that it may be a previously unrecognized young star; evidence for blob ejection in the wind of P Cygni; and evidence for disks around Wolf-Rayet stars

Visiting astronomer at numerous national and international observatory facilities

Acting Director, Ritter Observatory, University of Toledo, June 1999-Aug 2000

Co-Investigator (Astro-2) and project scientist (Astro-1) for the Wisconsin Ultraviolet Photo-Polarimeter Experiment (part of space shuttle Astro payload); worked operations console at Payload Operations Control Center during STS-35/Astro-1 and STS-67/Astro-2 missions; participated in determining science objectives and planning observations; coordinated ground-based support observations; provided scientific support during the mission; analyzed resulting data (lead scientist for Be star observations); Lead WUPPE operations flight controller, responsible for training and oversight of WUPPE operations personnel for Astro-2; assisted in WUPPE-related training of crew astronauts

Coordinated observing schedule and planning for Pine Bluff Observatory, University of Wisconsin; developed a means of meshing a number of different observing projects into a coordinated program; supervised and trained observing team (including graduate and undergraduate students)

Telescope/Instrument Experience:
NASA IRTF 3m + MIRLIN IR imager (also + IR bolometer); CTIO 1.5m + CFCCD + polarization module; SAO BTA 6m + PFES; Ritter Obs. 1m + echelle spectrograph; Pine Bluff Obs. 0.9m + HPOL; WUPPE; IUE; Sommers-Bausch Obs. 0.6m + 800x800 TI CCD (imaging and spectroscopy); MDM 2.4m + Wisconsin Echelle; IRAS data; Wyoming IR Obs. 2.4m; KPNO 4m + CryoCam; WIYN 3.5m + HPOL (also + CCD Imager); CCD commissioning team for Sommers-Bausch Obs., Univ. of Colorado (tested and characterized the instrument for spectroscopic use; developed observing techniques for spectroscopy and imaging)

Research Funding

Principal Investigator on NASA Long Term Space Astrophysics (LTSA) grant,  Research Corp. Cottrell Scholar Award, US CRDF grant, NASA ADP grant, 2 NASA IUE Guest Observer grants, and 2 NASA UV-Visible-Gravitational Astrophysics grants

Co-Principal Investigator, NASA Long Term Space Astrophysics (LTSA) grant

Co-Investigator, Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE)

Lead Investigator on 6 NASA IUE, IRAS, & ADP grants

Co-Investigator on 10 other funded NASA Guest Investigator programs (HST, IUE, ISO, EUVE, & ADP) and 1 VLA program (Proposal list available on request)

Teaching Experience

• 7 years teaching undergraduate astronomy courses and graduate seminars at University of Toledo
• 7 years supervising graduate and undergraduate research at University of Toledo
• 7 years supervising undergraduate observing/research at UW Pine Bluff Observatory - worked with undergrads on research projects for senior theses (and publication); guest lecturer, astronomy courses at University of Wisconsin
• 1 year teaching undergrad general astronomy courses at Front Range Community College, Westminster, CO
• 1 year teaching undergraduate general astronomy laboratories at the University of Colorado (as Graduate TA)
• 1 semester as Graduate TA for upper division undergraduate course in Galaxies & Cosmology at University of Colorado

• Master Teacher, 2001-2003, College of Arts & Sciences, University of Toledo
• Sigma Xi/Dion D. Raftopoulos Oustanding Research Award, 2001, University of Toledo
• Cottrell Scholars Award, 1999, Research Corporation
• Dean's Merit Award, 1999, College of Arts & Sciences, University of Toledo
• Dean's Merit Award, 1998, College of Arts & Sciences, University of Toledo
• NASA Group Achievement Award, 1996: Astro-2 Mission Team
• NASA Group Achievement Award, 1991: Astro-1 Payload Science Team
• NASA Group Achievement Award, 1991: Astro-1 Investigators Group
• Colorado Doctoral Fellow, 1982-1988
• Leids Kerkhoven-Bosscha award (research visit to the Netherlands), 1987
• U. of Colorado Graduate Student Foundation Fund Awards, 1983, 1986
• National Merit Scholar 1975; Martin Marietta Scholar 1975-1979

• American Astronomical Society (Member of Publications Board, 1996-99)
• Astronomical Society of the Pacific
• Association for Women in Science
• American Association of Physics Teachers
• American Association for the Advancement of Science
• Sigma Xi
• Sigma Pi Sigma
• Proposal review panels (IUE 1992,93; ADP, 1993; AAS/NSF REU, 1994; OSS 1998)
• Scientific Journal Referee (ApJ, AJ, PASP)
• Chair, Scientific Organizing Committee, Topical Session on Astrophysical Diagnostics from Polarimetry, American Astronomical Society meeting, June 1996.
• Member, Local Organizing Committee, 188th Meeting of the American Astronomical Society, held in Madison, WI, June 1996
• Member, Local Organizing Committee, 104th Annual Meeting of the Astronomical Society of the Pacific, held in Madison, WI, June 1992
• Member, Local Organizing Committee, IAU Colloquium No. 92: The Physics of Be Stars, held in Boulder, CO, August 1986

• Scientist partner, Project ASTRO (Ohio site)
• Scientist, TAPESTRIES program for elementary science education
• Developer and original PI, Universe in the Park program (NASA IDEA grant)
• Public lectures; workshops for elementary and secondary school teachers
• Visit schools to talk to students about astronomy and space sciences
• Served as a "mentor" for students interested in physics/astronomy careers
• Served as an advisor to an Explorer Post for junior high and high school students interested in astronomy and physics

Last updated 04 Jun 2003

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