Projectile Fragmentation Products, D.J.Morrissey
Modern accelerators can provide beams of large nuclei with kinetic energies that
are much larger than the repulsive Coulomb potential. When these energetic particles
react with a target nucleus, the projectile nucleus moves forward along a straight
lines past, or perhaps through, the edge of the target nucleus and is broken into
smaller parts. We have shown that the pieces of the projectile from such processes,
called projectile fragmentation reactions, are rather well described
by simple geometrical cross sections when coupled to statistical deexcitation
calculations of the intermediates. The momenta, or velocities, of the fragments
are very similar to the initial velocity of the beam and also can be described
by simple models. Probably the most important feature of these reactions is that
the forward-going fragments can be passed through an isotope separator that removes
the unreacted primary beam and other unwanted fragments to produce a secondary
beam of radioactive ions.
The National Superconducting Cyclotron Laboratory has a large fragment separator
(called the A1900) that we are using to produce and study
unknown exotic nuclei. In one of the first experiments using the A1200, the
predecessor of the A1900 device now retired, we observed several new nuclei
at the limit of nuclear stability. Such studies have extended our knowledge
of the most unstable nuclei with atomic numbers in the range of 30 to 50. We
have expanded our studies of these very exotic nuclei to include measurements
of the beta-decay half-lives of the most exotic nuclei and exotic decay modes.
Others have developed the technique of relativistic coulomb excitation for these
fast fragments and the fusion of exotic nuclei has been investigated.
Current Poster by E. Kwan: 
References
- Identification of New Nuclei Near the Proton-Drip Line for 30 -Z- 37,
M.F. Mohar, D. Bazin, W. Benenson, D.J. Morrissey, N.A. Orr, B.M. Sherrill,
D. Swan, J.A. Winger, A. Mueller, D. Guillemaud-Mueller, Phys. Rev. Lett.
66, 1571, (1991).
- New Nuclei near the Proton Drip Line around Z = 40, S.J. Yennello,
J.A. Winger, T. Antaya, W. Benenson, M.F. Mohar, D.J. Morrissey, N.A. Orr,
and B.M. Sherrill, Phys. Rev. C 46, 2620 (1992).
- The Identification of New Nuclei Near the Proton-drip Line, M. Hencheck,
R.N. Boyd, M. Hellstrom, D.J. Morrissey, M.J. Bables, F.R. Chloupek, M. Fauerbach,
C.A. Mitchell, R. Pfaff, C. Powell, G. Raimann, B.M. Sherrill, M. Steiner,
J. Vandergriff, and S.J. Yennello, Phys. Rev. C 50 , 2219 (1994).
- Projectile-like Fragment Momentum Distributions from 86 Kr
+ Al at 70 MeV/nucleon, R. Pfaff, D.J. Morrissey, M. Fauerbach, M. Hellstrom,
J.H. Kelley, R.A. Kryger, B.M. Sherrill, M. Steiner, J.S. Winfield, J.A. Winger,
S.J. Yennello, and B.M. Young, Phys. Rev.C 51, 1348 (1995).
- A New Search for 26O, M. Fauerbach, D.J. Morrissey, W.
Benenson, M. Hellstroem, J.H. Kelley, R.A. Kryger, R. Pfaff, C.F. Powell,
and B.M. Sherrill, Phys. Rev. C 53, 647 (1996).
- Fragmentation of 78-Kr Projectiles, R. Pfaff, D.J. Morrissey, M.
Fauerbach, M. Hellstroem, C.F. Powell, M. Steiner, and J.A. Winger, Phys.
Rev.C 53, 1753 (1996). --
Color Particle ID Figure
- Fusion Enhancement with Neutron-rich Radioactive Beams, K.E. Zyromski,
W. Loveland, G.A. Souliotis, D.J. Morrissey, C.F. Powell, O. Batenkov, K.
Aleklett, R. Yanez, I. Forsberg, M. Sanchez-Vega, J.R. Dunn, and B.G. Glagola,
Phys. Rev. C 55, R562 (1997).
- Coulomb Excitation of the One Neutron Halo Nucleus 11 Be,
M. Fauerbach, M.J. Chromik, T. Glasmacher, P.G. Hansen, R.W. Ibbotson, D.J.
Morrissey, H. Scheit, P. Thirolf, and M. Thoennessen, Phys. Rev. C 56,
(1997).
- Collectivity in 44S, T. Glasmacher, B.A. Brown, M.J.
Chromik, P.D. Cottle, M. Fauerbach, R.W. Ibbotson, K.W. Kemper, D.J. Morrissey,
H. Scheit, D.W. Sklenicka, and M. Steiner, Phys. Lett. B 395 , 163
(1997).
- Single Neutron Emission Following 11Li beta-Decay , D.J.
Morrissey, K.N. McDonald, D. Bazin, B.A. Brown, R. Harkewicz, N.A. Orr, B.M.
Sherrill, G.A. Souliotis, M. Steiner, J.A. Winger, S.J. Yennello, B.M. Young,
and S. Lukyanov, G. Chubarian, and Yu.Ts. Oganessian, Nucl. Phys. A 627
(1998) 222.
- Radioactive Nuclear Beam Facilities Based on Projectile Fragmentation,
D.J. Morrissey and B.M. Sherrill, Proc. Royal Soc. A 356 (1998) 1985.
- Heavy Residue Formation in 20 MeV/nucleon 197Au-12
C and 197Au-27Al Collisions, G.A. Souliotis, K.
Hanold, W. Loveland, D.J. Morrissey, A.C. Veeck, and G.J. Wozniak, Phys. Rev.
C 57 3129 (1998).
- Measurement of 81Kr in present-day and pre-nuclear atmospheric krypton
with accerator mass spectrometry, P. Collon, B. Davids, M. Fauerbach, R. Harkewicz, W. Kutschera, D.J. Morrissey, R. Pardo, M. Paul,
B.M. Sherrill, and M. Steiner, Radiochimica ACTA 85 (1999)
13.
- Direct Mass Measurements of Proton-rich Ge, As, Se, and Br Isotopes, G.F. Lima, A. L'epine-Szily, G. Audi, W. Mittig, M. Chartier, N.A.Orr, R. Lichtenhaler, J.C. Angelique, J.M. Casandjian, A. Cunsolo, C. Donzeaud, A. Foti, A. Gillibert, M. Lewitowicz, S. Lykynaov, M. MacCormick, D.J. Morrissey, A.N. Ostrowski, B.M. Sherrill, C. Stephan, T. Suomij"arvi, L. Tassan-Got, D.J. Vieira, A.C.C. Villari, and J.M. Wouters, Phys. Rev. C65 (2002) 044618.
- Heavy Residue Formation in 20 MeV/nucleon 197Au+90Zr Collisions,
G.A. Souliotis, W. Loveland, K. Hanold, G.J. Wozniak, and D.J. Morrissey,
Nucl. Phys. A 705, (2002) 279.
- First search for 16Be, T. Baumann, N. Frank, B.A. Luther, D.J. Morrissey,
J.P. Seitz, B.M. Sherrill, M. Steiner, J. Stetson, A. Stolz, M. Thoennessen,
and I. Wiedenhoever, Phys. Rev. C 67, 061303 (2003).
- Commissioning the A1900 Projectile Fragment Separator, Intl. Conf. on
Electromagnetic Separators and Ion Sources, D.J. Morrissey, B.M. Sherrill,
M. Steiner, A. Stolz, and I. Weidenhoever, EMIS14, Victoria, Canada, 6-10
May 2002, J. D'Auria, J. Thomson, M. Comyn, Eds., Nucl. Instrum. Meth. B
204 (2003) 90.
- In-Flight Separation of Projectile Fragments, D.J. Morrissey and
B.M. Sherrill, The Euroschool Lectures on Exotic Beams, J.S. Al-Khilili
and E. Roeckl, Editors, Lect. Notes Phys. 651 (2004) 113.
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