High energy astrophysics (X-ray, gamma-ray and cosmic-ray astronomy) offers an insight into some of the most energetic processes that take place in the universe. Through the development and use of a series of balloon-borne and space-borne experiments, my research attempts to explore some of these phenomena.
For my thesis research (at UNH), I worked on the development of a balloon-borne gamma-ray telescope. After completing my PhD in 1987, I spent the next two years as a postdoc at the Max Planck Institute for Extraterrestrial Physics near Munich, Germany, after which I returned to UNH. The focus of my early post-graduate research was the Compton Telescope experiment (COMPTEL) on NASA's Compton Gamma-Ray Observatory (CGRO). Launched by the Space Shuttle Atlantis in April of 1991, CGRO remained in orbit until it was de-orbited by NASA in June of 2000. My scientific studies with CGRO focused on research involving the accretion of matter onto compact objects (such as neutron stars and black holes), along with studies of high energy radiations from solar flares. Over the years, I have continued my research in high energy phenomena using data from several different satellite missions, including ROSAT, INTEGRAL, RHESSI, and Fermi.
In addition to analyzing data from numerous satellite missions, I have continued to be active in the development of new detector technologies for high energy missions. I have been especially interested in the development of technologies for studying X-ray and gamma-ray polarization from astrophysical sources. Studies of polarization from high energy sources should provide information on the geometry of the particle acceleration process and shed some light on the precise nature of the acceleration mechanism. The culmination of these efforts is a balloon experiment that we refer to as GRAPE. The first flight of the GRAPE payload is scheduled for the fall of 2011. The scientific goals of GRAPE include studies of pulsars, gamma-ray bursts and solar flares.
Other experimental efforts have included work with solid state gamma-ray detectors (such as CdZnTe), new scintillator technologies for gamma-ray detection (such as Lanthanum Bromideand Lanthanum Chloride) and various types of neutron detectors. Although the motivation for these developments is the study of astrophysical sources, several of these technologies may also have more practical applications. Our solid state gamma-ray detectors, for example, might be useful in several types of medical imaging applications. Our neutron telescope promises to be a useful tool for studying atmospheric radiations that adversely impact computers and other electrical equipment, particularly at high altitudes. They may also be useful as a monitor for nuclear waste management and for homeland security applications. As part of our research, we are exploring these other areas where our newly-developed technologies may prove valuable.
All of this research maintains a very active student involvement.Students play an integral part in all aspects of our work. This includes not only graduate students, but also undergraduate
Ph.D., Physics, University of New Hampshire
B.S., Physics, Case Western Reserve University
PHYS 400: Freshman Seminar
PHYS 405: Intro to Modern Astronomy
PHYS 407: General Physics I Recitation
PHYS 408: General Physics II Recitation
PHYS 444: The Final Frontier
PHYS 999: Doctoral Research
McConnell, M. L. (2017). High energy polarimetry of prompt GRB emission. New Astronomy Reviews, 76, 1-21. doi:10.1016/j.newar.2016.11.001
Bloser, P. F., Legere, J. S., Bancroft, C. M., Ryan, J. M., & McConnell, M. L. (2016). Balloon flight test of a Compton telescope based on scintillators with silicon photomultiplier readouts. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 812, 92-103. doi:10.1016/j.nima.2015.12.047
Bloser, P. F., Legere, J. S., Bancroft, C. M., Jablonski, L. F., Wurtz, J. R., Ertley, C. D., . . . Ryan, J. M. (2014). Testing and simulation of silicon photomultiplier readouts for scintillators in high-energy astronomy and solar physics. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 763, 26-35. doi:10.1016/j.nima.2014.06.016
Hunter, S. D., Bloser, P. F., Depaola, G. O., Dion, M. P., DeNolfo, G. A., Hanu, A., . . . Stecker, F. W. (2014). A pair production telescope for medium-energy gamma-ray polarimetry. Astroparticle Physics, 59, 18-28. doi:10.1016/j.astropartphys.2014.04.002
Ertley, C., Bloser, P., Connor, T., Legere, J., McConnell, M. L., & Ryan, J. M. (2012). Measuring the Polarization of Hard X-Ray Solar Flares with GRAPE. AGU Fall Meeting Abstracts.
McConnell, M. L., Zdziarski, A. A., Bennett, K., Bloemen, H., Collmar, W., Hermsen, W., . . . Strong, A. W. (2002). The Soft Gamma‐Ray Spectral Variability of Cygnus X‐1. The Astrophysical Journal, 572(2), 984-995. doi:10.1086/340436
Kuiper, L., Hermsen, W., Cusumano, G., Diehl, R., Schönfelder, V., Strong, A., . . . McConnell, M. L. (2001). The Crab pulsar in the 0.75-30 MeV range as seen by CGRO COMPTEL. Astronomy & Astrophysics, 378(3), 918-935. doi:10.1051/0004-6361:20011256
Atkins, R., Benbow, W., Berley, D., Chen, M. L., Coyne, D. G., Dingus, B. L., . . . Yodh, G. B. (2000). Evidence for T[CLC]e[/CLC]V Emission from GRB 970417[CLC]a[/CLC]. The Astrophysical Journal, 533(2), L119-L122. doi:10.1086/312629
Briggs, M. S., Band, D. L., Kippen, R. M., Preece, R. D., Kouveliotou, C., van Paradijs, J., . . . Wijers, R. A. M. J. (1999). Observations of GRB 990123 by theCompton Gamma Ray Observatory. The Astrophysical Journal, 524(1), 82-91. doi:10.1086/307808
Schoenfelder, V., Aarts, H., Bennett, K., de Boer, H., Clear, J., Collmar, W., . . . Winkler, C. (1993). Instrument description and performance of the Imaging Gamma-Ray Telescope COMPTEL aboard the Compton Gamma-Ray Observatory. The Astrophysical Journal Supplement Series, 86, 657. doi:10.1086/191794