Cecil J. Waddington

I am a member of three collaborations studying various aspects of cosmic ray physics. Members of these collaborations include individuals from Washington University, St. Louis, Goddard space Fight Center, and CalTech. We have completed the TIGER program to study heavy nuclei in the cosmic radiation by making flights in Antarctica. The results from this experiment have been submitted to Ap J for publication. NASA has recently funded for a period of 5 years the SUPER TIGER program which will enhance the tiger program with a much larger and more powerful detector. Building of this detector is just beginning. NASA also funded us, together with colleagues from NASA Huntsville, to prepare a proposal OASIS which will include the ENTICE experiment, which will study the entire charge spectrum of nuclei in the cosmic radiation above Fe, including the actinides.

These programs are described in a series of abstract that will be submitted to the forthcoming Cosmic Ray Conference in Poland this summer. Preliminary copies of two of these are included.

ENTICE

Session OG1.5
Poster paper

Title: The Energetic Trans-Iron Nuclei Experiment (ENTICE)

W.R. BINNS, M.H. ISRAEL, Washington University, St. Louis, MO 63130, A.C.
CUMMINGS, A.W. LABRADOR, R.A. MEWALDT, R.A. LESKE, E.C. STONE, California
Institute of Technology, Pasadena, CA 91125, M.E. WIEDENBECK, Jet Propulsion
Laboratory, E.R. CHRISTIAN, G.A. DENOLFO, T. HAMS, J.T. LINK, J.W. MITCHELL,
M. SASAKI, NASA/Goddard Space Flight Center, Greenbelt, MD 20771, J.H.
ADAMS, NASA/Marshall Space Flight Center, Huntsville, AL, C.J. WADDINGTON,
Univ. of Minnesota, Minneapolis, MN 55455

The ENTICE experiment is one of two instruments that comprise the "Orbiting Astrophysical Spectrometer in Space (OASIS)" which is presently undergoing a NASA "Astrophysics Strategic Mission Concept Study." ENTICE is designed to make high precision measurements of the abundances of individual elements from neon through the actinides and, in addition, will search for possible superheavy nuclei in the galactic cosmic rays. The ENTICE instrument utilizes silicon detectors, aerogel and acrylic Cherenkov counters, and a scintillating optical fiber hodoscope to measure the charge and energy of these ultra-heavy nuclei for energies greater than 0.3 GeV/nucleon. It is a large instrument consisting of four modules with a total effective geometrical factor of ~20 m2sr. Measurements made in space for a period of 3 years with ENTICE will enable us to determine if cosmic rays include a component of recently synthesized heavy elements (Pu and Cm), what the age of that component is, and test the model of the OB association origin of galactic cosmic rays. Additionally, it will enable us to study how diffusive shock acceleration of cosmic rays operates differently on interstellar grains and gas.

This research was supported by NASA under Grant NNM08AA10A


SUPER TIGER

"Identifying Galactic Cosmic Ray Origins with Super-TIGER"


G.A. de Nolfo, W.R. Binns, M.H. Israel, E.R. Christian, J.W. Mitchell,T.Hams, J.T. Link, M. Sasaki, A.W. Labrador, R.A. Mewaldt, E.C. Stone, M.E. Wiedenbeck, C.J. Waddington

Super-TIGER (Super Trans-Iron Galactic Element Recorder) is a new long-duration balloon-borne instrument designed to test and clarify the emerging model of cosmic-ray origin in OB associations as well as models for atomic processes by which nuclei are selected for acceleration. A sensitive test of the origin of cosmic rays is the measurement of ultra heavy elemental abundances (Z ³ 30). Super-TIGER is a large-area (2.50 m2 sr ) instrument designed specifically to measure the elements of atomic number Z in the interval 30≤ Z≤ 42 with individual-element resolution and high statistical precision, and extend the range through Z=56. It will also measure with high statistical accuracy the energy spectra of the more abundant elements of 14≤ Z≤ 29 at energies 0.8≤ E≤ 10 GeV/nucleon. These spectra will give a sensitive test of the hypothesis that microquasars or other sources could superpose spectral features on the otherwise smooth energy spectra previously measured with less statistical accuracy. Super-TIGER builds on the heritage of the smaller TIGER, successfully flown from Antarctica in 2001 and 2003 for total of 50 days of data and producing the first well-resolved measurements of elemental abundances of the elements 31Ga, 32Ge, and 34Se. In addition, Super-TIGER is a forerunner of a similar instrument, the Energetic Trans-Iron Composition Experiment (ENTICE), that is a part of the Orbiting Astrophysical Spectrometer in Space (OASIS), one of the NASA Astrophysics Strategic Mission Concept Studies. ENTICE would have sufficient exposure and resolution to measure even the rarest individual elements including the actinides, 90Th, 92U, 94Pu, and 96Cm. We present the Super-TIGER design, schedule, and progress to date, and discuss the relevance of UH measurements to cosmic-ray origins.