Astrophysics

About Us

The Astrophysics Group has carried out studies from high altitude balloons and from spacecraft. The principal UNH satellite-based studies were carried aboard the Solar Maximum Mission and the Gamma Ray Observatory satellites. The UNH detectors measured emissions from the sun and from a number of galactic sources. Galactic gamma rays often are produced by the most dynamic and highest temperature plasmas in the universe. Efforts have concentrated on identifying and mapping sources, on studying the time dependence of emissions, on determining the spectrum and line structure of the sources, and on studies of the cosmic diffuse background radiation. 

X-Calibur Telescope
This multi-institute project team is preparing the X-Calibur telescope for a stratospheric balloon flight launched from McMurdo (Antarctica) in December 2018. The telescope will be used to observe the X-Ray emission from a sample of black holes, neutron stars, and pulsars in our Milky Way galaxy. X-Calibur will measure the polarization  (the plane in which the electric field of the X-rays oscillates) of the high-energy X-ray emission. The polarization holds information about how and where the X-Ray emission originates. The team hopes to gain new insights into how black holes in a binary orbit with stars grow by gobbling up stellar matter. Furthermore, they will observe X-rays from neutron stars – 12-km-radius objects with masses exceeding the mass of our sun.

Advanced Scintillator Compton Telescope (ASCOT)
This project uses modern scintillator materials read out by silicon photomultipliers to create a sensitive gamma-ray telescope for astronomical observations.  A prototype instrument was flown on a NASA scientific balloon in July 2018.

Above: Tejaswita Sharma, Peter Bloser, and Jason Legere at the launch of ASCOT in July 2008.

The Compton Telescope on CGRO (COMPTEL)
We continue to analyze data from the COMPTEL instrument on the Compton Gamma Ray Observatory (CGRO), which flew on orbit from 1991-2000. In particular, we have recently been studying polarization of GRBs and solar flares, and are also studying atmospheric neutrons.

Field Deployable Imaging Neutron Detector (FIND)
Funded by the Defense Threat Reduction Agency, this project is using modern organic scintillators read out by silicon photomultipliers to construct a portable camera for fast neutrons and gamma rays suitable for military and homeland security-related applications.

Diamond Scattering Detectors for Compton Telescopes
We are investigating whether artificial single-crystal diamond detectors may be used as Compton scattering elements in advanced Compton telescopes. Diamond detectors offer the prospect of improved energy and position resolution while maintaining the fast timing of scintillators.

Gamma-Ray Concentrator
We are investigating whether thin-film multilayer structures may be used to channel and concentrate soft gamma rays from a large collecting area to a small detector.  This technique has the potential to dramatically improve the sensitivity of future gamma-ray telescopes.

Gamma Ray Polarimeter Experiment (GRAPE)
Theoretical models show that a more complete understanding of the inner structure of γ-ray bursts (GRBs), including the geometry and physical processes close to the central engine, requires the exploitation of γ-ray polarimetry. Over the past several years, we have developed the Gamma Ray Polarization Experiment (GRAPE) to measure the polarization of γ-rays from GRBs over the energy range of 50 to 500 keV. GRAPE is a large FoV instrument with a sensitive energy range covering the peak energy distribution of GRBs. The design is based on an array of independent modules, each of which consists of an array of (high-Z and low-Z) scintillator elements read out by a multi-anode PMT (MAPMT). Our eventual goal is to fly GRAPE on a long duration balloon (LDB) platform to collect data on a significant sample of GRBs. Our experience with two balloon flights (in 2011 and 2014), coupled with further design efforts focused on orbital payloads, has led to an improved polarimeter concept that represents a natural evolution of the current design. 

Ph.D. Thesis Projects

Dr. Richard Woolf
Graduation Date: 2010 
Advisor: James Ryan
Thesis Title: Development and Characterization of a Fast Neutron Imaging Telescope (FNIT) for 1-20 MeV Neutrons from the Sun and Nuclear Material
Current Position : Naval Research Laboratory, Washington, D.C.

Dr. Trevor Morgan
Graduation Date: 2010
Advisor: James Ryan
Thesis Title: Measurements of the 2001 April 15 and 2005 January 20 Ground-Level Enhancements by the Milargro Water Cerenkov Detector

Dr. Burcin Dönmez
Graduation Date: 2006 
Advisor: James Ryan
Thesis Title: Characterization of Single-Sided CdZnTe Strip Detectors for High Energy Astrophysics Applications
Thesis Availability: 
Astrophysics Data System Entry

Dr. Abe Falcone
Graduation Date: 2001 
Advisor: James Ryan
Thesis Title: Observation and Study of GeV Solar Energetic Particles Using the Milagrito Extensive Air Shower Detector
Thesis Availability:
Astrophysics Data System Entry
Current Position : Senior Research Associate, Dept. of Astronomy and Astrophysics, Penn State University

Dr. C. Alex Young
Graduation Date: 2001 
Advisor: James Ryan
Thesis Title: Solar flare gamma-ray spectroscopy with CGRO-COMPTEL
Thesis Availability
Astrophysics Data System Entry
Current Position: Solar Astrophysicist, NASA Goddard Space Flight Center, Greenbelt, MD

Dr. Martina Arndt
Graduation Date: 2000 
Advisor: James Ryan
Thesis Title: X- and Gamma-Ray Observations of the 15 November 1991 Solar Flare
Current Position: Associate Professor and Chair, Dept. of Physics, Bridgewater State University, Bridgewater, MA

Dr. S. Cheenu Kappadath
Graduation Date: 1998 
Advisor: James Ryan 
Thesis Title: Measurement of the Cosmic Diffuse Gamma-Ray Spectrum from 800 keV to 30 MeV
Astrophysics Data System Entry
Current Position: Assistant Professor, Department of Imaging Physics, Division of Diagnostic Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX

Dr. Benjamin Hersh
Graduation Date: 1996 
Advisor: James Ryan 
Thesis Title: Photometric Studies of Cygnus X-1 from 322-473 keV with the Solar Maximum Mission
Astrophysics Data System Entry

Dr. Richard S. Miller
Graduation Date: 1995 
Advisor: Dr. James M. Ryan 
Thesis Title: A Search for Radiative Neutrino Decay and Its potential Contribution to the Cosmic Diffuse Gamma-Ray Background
Astrophysics Data System Entry
Current Position: Associate Professor, Dept. of Physics, University of Alabama, Huntsville, AL

Dr. R. Marc Kippen
Graduation Date: 1995 
Advisor: James Ryan 
Thesis Title: Locations and Spectra of Cosmic Gamma-Ray Bursts
Astrophysics Data System Entry
Current Position: Project Leader / Technical Staff Member, Space Science & Applications Group, Los Alamos National Laboratory, Los Alamos, NM

Dr. Douglas A. Biesecker
Graduation Date: 1994 
Advisor: James Ryan 
Thesis Title: On the Occurence of Solar Flares Observed with thw Burst and Transient Source Experiment
Astrophysics Data System Entry
Current Position: Solar Physicist, NOAA Space Weather Prediction Center, Boulder, CO

Dr. Debadarshi Bhattacharya
Graduation Date: 1990
Advisor: Dr. Edward Chupp
Thesis Title:Observations of Cosmic Gamma - Ray Sources and Their Contribution to the Diffuse Gamma - Ray Background
Astrophysics Data System Entry

Dr. Renu Saxena
Graduation Date: 1990 
Advisor: James Ryan 
Thesis Title: Ground Level Atmospheric Neutron Flux Measurements in the 10-170 MeV Range
Astrophysics Data System Entry
Current Position: Medical Physicist, Stereotactic Radiosurgery Institute, Gurnee, IL

Dr. Parameswaran Sreekumar
Graduation Date: 1989 
Advisor: John Lockwood 
Thesis Title: Ground Level Atmospheric Gamma Ray Flux Measurements in the 1-6 MeV Range
Astrophysics Data System Entry
Current Position: Head of Space Astronomy and Instrumentation, Indian Space Research Organization, ISRO Satellite Center, Bangalore, India

Dr. Mark L. McConnell
Graduation Date: 1987 
Advisor: Edward Chupp 
Thesis Title: Gamma Ray Imaging Observations of the Crab and Cygnus Regions
Astrophysics Data System Entry
Current Position: Professor, Dept. of Physics, University of New Hampshire

M.S. Thesis Projects

Jason Legere
Graduation Date: 2005 
Advisor: Mark McConnell
Thesis Title: Developing a Compton Polarimeter to Measure Polarization of Hard X-Rays in the 50-300 keV Energy Range
Thesis Availability:
Current Position: Project Manager, Space Science Center, University of New Hampshire

Mickel McClish
Graduation Date: 2002 
Advisor: James Ryan
Thesis Title: The Characterization of Orthogonal Coplanar Strip CZT Detectors of 5 and 10 mm Thickness
Current Position: Staff Scientist, Radiation Monitoring Devices, Watertown, MA

Kipp Larson
Graduation Date: 2000
Advisor: Dr. Alen D. Drake (Electrical Engineering)
Thesis Title: Analog Circuit for Measuring the Depth of Interaction of Gamma - Ray Events in a CZT Strip Detector with Coplanar Anodes
Current Position: Deputy Mission Operations Manager for Kepler Spacecraft, Ball Aerospace, Boulder, CO

Cornelia B. Wunderer
Graduation Date : 1997 
Advisor: James Ryan 
Thesis Title: Feasibility Study of SONTRAC - A Neutron Tracking Telescope for Solar, Atmospheric and Other Applications
Current Position: German Electron Synchrotron Radiation Facility (DESY), Hamburg, Germany 

C. Alex Young
Graduation Date: 1996 
Advisor: Dawn Meredith (Physics) 
Thesis Title: Wavelet Based Analysis of Cosmic Gamma-Ray Burst Time Series
Current Position: Solar Astrophysicist, NASA Goddard Space Flight Center, Greenbelt, MD

Brian K. Dann
Graduation Date: 1996 
Advisor: Allen Drake (Electrical Engineering) 
Thesis Title: Front End Electronics Development for the Minute-of-Arc Resolution Gamma-Ray Imaging Experiment

Sandra J. Fletcher
Graduation Date: 1995 
Advisor: Mark McConnell 
Thesis Title: The Search for Celestial 2.2 MeV Neutron Capture Line
Thesis Availability:

Raid M. Suleiman
Graduation Date: 1995 
Advisor: James Ryan 
Thesis Title: COMPTEL Measurements of Nuclear Gamma-Ray Lines in Solar Flares
Current Position: Solar & Stellar Physics Division, Harvard-Smithsonian Center for Astrophysics, Cambridge, MA

R. Marc Kippen
Graduation Date: 1991 
Advisor: James Ryan 
Thesis Title: Monte Carlo Simulation of the COMPTEL Gamma-Ray Telescope
Current Position: Project Leader / Technical Staff Member, Space Science & Applications Group, Los Alamos National Laboratory, Los Alamos, NM

Kent Reinhard
Graduation Date: 1989 
Advisor: James Ryan 
Thesis Title: Neureal Network Approach to Event Location with an Anger Camera for Gamma-Ray Astronomy
Thesis Availability:
Current Position: Physics, Astronomy & Engineering Instructor, Southeast Community College, Lincoln, NE

Senior Thesis Projects

Shirley Dame
Graduation Date: 2011
Advisor: Mark McConnell
Project Title:A Study of the Orbital Neutron Albedo Flux with COMPTEL

Tuyen Nguyen
Graduation Date: 2008
Advisor: Mark McConnell
Project Title: INTEGRAL Analysis of a 2.2 MeV Source Candidate

Procheta Mallik
Graduation Date: 2005
Advisor: James Ryan
Project Title: Analysis and Design Optimization of FNIT - A Fast Neutron Imaging Telescope

Eric Foley
Graduation Date: 2003
Advisor: Mark McConnell
Project Title: Imaging the Gamma-Ray Sky at 2.2 MeV

Leila Mizouni
Graduation Date: 2002
Advisor: Mark McConnell
Project Title: A Study of Gamma-Ray Emissions from a Black Hole Binary System