Professor of Physicsfinley@purdue.edu
Office: Physics 302
Telephone: (765) 494-5048
Fax: (765) 494-0706
B.S., Physics 1984 West Chester University
Ph.D., Physics 1990 University of Wisconsin-Madison
Prof. Finley carries out a multi-wavelength research program in astrophysics with a primary emphasis on the physics of compact objects and their interstellar environs. The research program involves data acquired at optical wavelengths (energies ~ eV) through the very high energy gamma-ray (energies ~1012 eV). Compact objects are endpoints of stellar evolution and their extremes of density (p > pNuclear), magnetic field (B ~1012 Gauss), and temperature (TSurface > 106 K) present unique laboratories for the study of matter which can not be duplicated in a terrestrial setting. The physics and astronomy issues which are addressed in this research touch upon many fundamental physics issues: the equation of state of ultradense matter, the nature of matter in the presence of large magnetic fields, the coupling between the stellar matter and the dynamics of the stellar rotation, the electrodynamics of the magnetosphere and the origin of the cosmic rays, the origin of the "pulsar" mechanism, and the nature of the massive compact objects which lie at the heart of active galactic nuclei to name a few. Insight into these issues requires a comprehensive overview of the energetics in the optical, ultraviolet, X-ray, and gamma-ray energy bands of the electromagnetic spectrum. Prof. Finley participated in optical campaigns utilizing large telescopes of the National Optical Astronomy Observatory at both Kitt Peak in Arizona and Cerro Tololo in Chile, the National Observatory of Mexico(UNAM) in Baja California, Mexico and the European Southern Observatory (ESO) at Cerro La Silla in Chile. The ultraviolet, X-ray, and low energy gamma-ray studies have been carried out as a guest observer with several orbiting space based telescopes operated by NASA: the Extreme Ultraviolet Explorer (EUVE) in the UV domain; the Roentgen Satellite (ROSAT), the Advanced Satellite for Cosmology and Astrophysics (ASCA), and Chandra in the soft X-rays; the Rossi X-ray Timing Explorer (RXTE) and the Compton Gamma-Ray Observatory (CGRO) in the hard X-ray/gamma-ray region. At the highest accessible gamma-ray energies, as part of the VERITAS collaboration, Prof. Finley utilizes the 10m telescope at the Fred Lawrence Whipple Observatory on Mt. Hopkins in Southern Arizona.
Future research efforts involve the pursuit of the above outlined avenues of investigation utilizing the next generation of detectors in both the VHE gamma-ray domain and aboard X-ray/Gamma ray satellites. Prof. Finley is presently involved in the construction phase of a large project called VERITAS (the Very Energetic Radiation Imaging Telescope Array System), an array of 7 VHE gamma-ray telescopes which is the next step in ground based gamma-ray astronomy. The array, when complete, will push the sensitivity and energy threshold down by yet another order of magnitude and will overlap in bandpass with space based observatories for the first time. This proposal won an internal Smithsonian competition and construction began in fiscal year 2003 and will extend through fiscal year 2006. Funds in support of the Purdue effort originate with the Department of Energy. Prof. Finley plans to explore advanced detector designs utilizing recent technologies such as avalanche photodiodes (APDs) and hybrid photomultipliers for this effort. This project is expected to have duration well into the second decade of this millennium.
The research which Prof. Finley pursues in the X-ray domain will continue with advanced detectors which are soon to be placed in orbit by NASA. The large bandpass, imaging capabilities, and spectral resolution of CHANDRA will allow the programs which he has been carrying out to become more refined. The expected duration of the CHANDRA mission has a baseline of 10 years and will probably proceed beyond that time frame. The current suite of space based detectors which he has been utilizing as a guest observer will gradually be phased out over the first few years of the CHANDRA mission but will still be viable research tools in the interim.