Employment and Practical Training Opportunities

Updated August 5, 2008

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Staff Scientist Positions

Experiment: Position no.: 312570 PHY

Theory: Position no.: 312571 PHY

• NB. Follow the links to submit official application material. Before doing so, however, read on for additional information.

The Physics Division at Argonne National Laboratory invites applications and nominations for two staff positions in Nuclear Astrophysics. The positions are open for immediate occupation. We aim to recruit both an outstanding experimentalist and an outstanding theorist. The succssful candidates will be able to conduct a novel and vigorous research program in nuclear astrophysics with relevance to a future radioactive ion beam facility.

We are seeking candidates with an outstanding record of past accomplishments and great promise for future growth in research. We plan to appoint at the rfank of Asst. Physicist (Ph.D. plus at least two years Postdoc experience). However, an appointment at the level of Physicist (Ph.D. plus at least 3-5 years experience) might be considered should circumstances warrant.

For additional information, applicants should contact

• Craig Roberts
  Physics Division Argonne
  National Laboratory
  Argonne, IL 60439
  Tel: + 1 630 252 4095
  Fax: + 1 630 252 3903
  E-mail: cdroberts@anl.gov

A complete submission will contain a

• curriculum vitae
• list of publications
• list of people prepared to provide a letter of reference on behalf of the applicant and their addresses
• a brief description (not more than 3 pages) of research interests and goals.

As indicated above, the official application material must be submitted on-line.

Argonne is one of the pre-eminent multidisciplinary research facilities in the Nation, located about 25 miles southwest of Chicago. It is a U.S. Department of Energy laboratory managed by UChicago Argonne, LLC. The Physics Division has a staff of about 100, including 33 Ph.Ds and 17 postdoctoral scholars, and has major research programs in low-energy nuclear physics, nuclear and hadron theory, medium energy nuclear physics, and accelerator technology. The division operates the Argonne Tandem-Linac Accelerator Facility (ATLAS) as a national user facility for low-energy nuclear physics. ATLAS is currently being upgraded to increase its capabilities for rare isotope beams via the Californium Rare Isotope Beam Upgrade (CARIBU). The future construction of a major new facility for rare isotope physics is an important strategic goal for the division and the laboratory.

Support Staff Positions

Career opportunities at Argonne may be accessed at http://www.anl.gov/Careers/index.html

Argonne is an equal opportunity employer and we value diversity in our workforce.

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Postdoctoral and Visiting Scientist Appointments

Postdoctoral appointments are available in all the research programs of the Physics Division. The appointments are made for one-year periods but may be extended. Visiting Scientist appointments are available to individuals on leave from their parent institutions who will return on completion of their Argonne assignment. Interested individuals may inquire themselves or be recommended by Physics Division staff.

Low-energy Nuclear Physics:

Information on the low-energy research program may be found at http://www.phy.anl.gov/lep/index.html.

Medium-energy Nuclear Physics:

Information on the medium-energy program may be found at

http://www.phy.anl.gov/mep/index.html.

Theoretical Nuclear Physics:

Current postdoctoral opportunities in the Theoretical Nuclear Physics program may be viewed at http://www.phy.anl.gov/theory/positions.html.

ATLAS Accelerator:

Information on the ATLAS Accelerator may be viewed at http://www.phy.anl.gov/atlas/index.html

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Educational Programs and Student Appointments 

The Physics Division offers college/university faculty and students opportunities to participate in ongoing research projects. The various research participation programs are administered by Argonne’s Division of Educational Programs. Specific information on individual programs may be obtained from the Division of Educational Programs and is available online at http://www.dep.anl.gov.

SUPERCONDUCTING HEAVY-ION LINAC "ATLAS"

The Physics Division is the home of the world’s first superconducting ion accelerator, the Argonne Tandem Linac Accelerator Systems, ATLAS. This accelerator is based on superconducting radio-frequency resonators and can accelerate any ion from ones as light as protons (atomic mass 1) to ones as heavy as uranium (atomic mass 238). ATLAS is a Department of Energy National User’s Facility that provides high quality ion beams for basic research in nuclear science as described in the next section. The accelerator physics staff based at ATLAS is active in a variety of research and development projects. The topics include superconducting radio-frequency resonator, ion sources based on microwave-heated plasmas, ion beam dynamics simulations, computer control systems, and other related topics. Much of the present research and development is directed towards the components of a proposed advanced accelerator called the Rare Isotope Accelerator, RIA. It is based on extensions of the present ATLAS technology and involves extending superconducting heavy ion linear accelerators to much higher energies and beam power. Topics currently being pursued for this new project also include the design and testing of high-power targets and associated ion sources for the production, extraction, and ionization of short-lived radioisotopes. Novel methods are also being developed for the efficient acceleration of these rare isotopes.

NUCLEAR REACTIONS AND NUCLEAR STRUCTURE STUDIES BY HEAVY IONS

Nuclear structure and reactions are studied in collisions between complex nuclei with heavy-ion beams mostly from the Argonne Tandem-Linac Accelerator (ATLAS), a national heavy-ion users' facility. The major thrusts of this program are three-fold: (a) the understanding of the nucleus as a many-body system built of protons and neutrons and governed by the strong force, (b) the exploration of the origin of the chemical elements and their role in shaping the reactions that occur in the cataclysmic events of the cosmos and (c) tests of the limits of validity of the Standard Model, the fundamental theory that currently best represents our understanding of the laws and fundamental symmetries of Nature. The specific current research topics include the development and acceleration of short-lived nuclei and their use in measurements of cross-sections of astrophysics interests as well as in nuclear structure and reaction dynamics studies; the production and study of nuclei at the very limits of stability, including the discovery of new proton emitters near the drip line, and the study of the properties of very heavy elements (actinide and transfermium (Z>100) nuclei), the study of exotic nuclear shapes; the delineation of the essential parameters governing dynamics of reactions between heavy nuclei; tests of current descriptions of the weak force. These efforts are based on forefront instrumentation available at ATLAS which includes: (1) the Fragment Mass Analyzer, which separates nuclear reaction products from the beam and transports them to a detection station; (2) the Canadian Penning Trap, which measures nuclear masses with unsurpassed accuracy; (3) a magnetic spectrograph for the detection of high-velocity reaction products; (4) a large, versatile reaction chamber; and (5) a number of gamma-ray detectors including Compton-suppressed germanium spectrometers and NaI and BaF2 scintillators. At the present time, Gammasphere, the national gamma-ray facility composed of 110 Compton-suppressed, large volume Ge detectors is also installed at ATLAS. There are always opportunities for research participants to be involved in every aspect of the program from the development of detectors to the actual running of experiments, and from the analysis of data to the development of simulations and/or calculations to assist in the interpretation of the results.

NUCLEAR PHYSICS AT INTERMEDIATE ENERGIES

The origin of the basic nuclear force between nucleons is explored in our program of Nuclear Physics at Intermediate Energies. In particular, the role of the constituents of the nucleons, i.e. quarks and gluons in a fundamental description of nuclear forces is examined in experiments primarily utilizing electromagnetic probes. A number of studies are currently in progress at the TJNAF (Thomas Jefferson National Accelerator Facility). Physics Division staff members led in the construction of experimental facilities, serve as spokespersons for a number of experiments, and are actively involved in others. A second major component of our program is the study of the origin of the spin of the nucleon. Physics Division staff play a major role in HERMES, a broadly based international collaboration devoted to the study of the spin structure of the nucleon using internal polarized targets in the HERA storage ring at DESY (Deutsches Elektronen-Synchrotron), Hamburg, Germany. A third component, high energy experiments to probe the structure of the quark sea in the nucleon, to be performed at Fermilab (Fermi National Accelerator Laboratory) are also in the early stages of planning. Opportunities exist for research participants to be involved in all aspects of our work.

THEORY RESEARCH

Theory research in the Physics Division addresses a broad range of important problems in nuclear astrophysics, and nuclear physics involving the structure and dynamics of hadrons and nuclei. There is strong emphasis on comparison with data from Argonne's ATLAS facility, from JLab, and from other laboratories around the world; and identifying and predicting phenomena that can be explored with a rare isotope accelerator. The Theory Group has five principal areas of research: (i) the modeling and application of quantum chromodynamics (QCD) to light- and heavy-hadron structure at zero temperature and density, and at the extremes of temperature and density appropriate to the early universe, neutron stars, and RHIC experiments; (ii) the development of reaction theories for use in exploring hadron structure using the data from meson and nucleon-resonance production experiments at JLab, MIT-Bates and Mainz; (iii) the construction of realistic two-and three-nucleon potentials that give accurate fits to nucleon-nucleon elastic scattering data and properties of light nuclei, and their use in detailed many-body calculations of light and near closed-shell nuclei, nuclear matter and neutron stars, and in a variety of astrophysically important electroweak reactions; (iv) the investigation of nuclear processes that take place in stars, in the big bang, and in interstellar and intergalactic space; and (v) nuclear structure and reaction studies, which include a focus on high-spin deformation and the structure nature's heaviest elements, and coupled-channels calculations of heavy-ion reactions near the Coulomb barrier and calculations of observables in breakup reactions of nuclei far from stability. Additional research is pursued in atomic physics, neutron physics, quantum computing, and fundamental quantum mechanics. Several of our projects involve major numerical simulations using the massively parallel computer systems at Argonne and NERSC. Many projects also involve collaborators, student and staff, at US and foreign universities, and other national laboratories.

CATCHING RARE ATOMS WITH LIGHT

Zheng-Tian Lu

Research homepage: http://www.phy.anl.gov/mep/atta/

The ability to control an atom, both its internal and external degrees of freedom, has improved dramatically since the time of the classic Stern-Gerlach experiment. Rapid progress has occurred in recent years due to exciting developments in the field of laser spectroscopy and laser manipulation of atoms. Using precisely controlled laser beams, an atom can be spatially confined in a trap, cooled so that it barely moves, and induced into a quantum superposition of multiple states. My colleagues and I develop new and improve existing methods of controlling atoms, and use these methods to explore scientific problems in the realm of physics and beyond. The following is a brief description of a few on-going projects of our group.

Testing time-reversal symmetry in atoms and nuclei.

We are searching for a permanent electric-dipole moment (EDM) of the Ra-225 atom. A positive finding would signify the violation of time-reversal symmetry (T) and, under the assumption of CPT invariance, the charge-parity symmetry (CP). CP violation was first discovered by Prof. James Cronin and co-workers in neutral Kaon decays, and can be explained by the Kobayashi-Maskawa (KM) mechanism within the framework of the Standard Model. While the KM mechanism gives rise to a negligible EDM, extensions to the Standard Model such as supersymmetry (SUSY), multi-Higgs models, and left-right symmetric models generally predict a relatively large EDM within the reach of this experiment. Therefore, this experiment provides an outstanding opportunity to search for new physics beyond the Standard Model. The Ra-225 nucleus is an especially good case because it has the characteristics of octupole deformation, which leads to a large enhancement of the T-violating Schiff moment. We have succeeded in realizing laser trapping and cooling of radium atoms (both Ra-226 and Ra-225) for the first time in the world. We plan to transfer the trapped Ra-225 atoms to an optical dipole trap, polarize them through optical pumping, and perform EDM measurements.

Studying exotic nuclear structure.

Although Quantum Chromodynamics (QCD) has been firmly established as the fundamental theory of the strong interaction, it is still technically not possible to calculate the structure of simple nuclei based on QCD. This insufficient understanding offers experimenters the opportunity to participate in the development of nuclear structure models and the possibility of discovering new structure. We are conducting experiments based on precision laser spectroscopy of helium atoms: 1) We have determined the charge radius of the lightest halo nucleus He-6 (t_1/2 = 0.8 s) by performing laser spectroscopy on individual He-6 atoms confined in an atom trap. This result helps reveal the structure of this neutron-rich nucleus and constrain models of the three-nucleon force. A more challenging goal for us is to study He-8 (t_1/2 = 0.1 s), which is the most neutron-rich matter on Earth. (2) We have searched for stable, helium-like strangelets in the Earth’s atmosphere. The null results set stringent upper limits on the abundance of such anomalous particles.

Radio-krypton dating - from dream to practice.

Since radiocarbon dating was first demonstrated by Prof. Willard Libby at our university in 1949, the field of trace analyses of long-lived cosmogenic isotopes has seen steady growth in both analytical methods and applicable isotopes. The impact of such analyses has reached a wide range of scientific and technological areas. A new method, named Atom Trap Trace Analysis (ATTA), was developed by our group and used to analyze Kr-81 (t_1/2 = 2.3x10^5 years, isotopic abundance ~ 1x10^-12) in environmental samples. In this method, individual Kr-81 atoms are selectively captured and detected with a laser-based atom trap. 81Kr is produced in the upper atmosphere by cosmic-ray induced spallation and neutron activation of stable krypton isotopes. It is the ideal tracer for dating ice and groundwater in the age range of 10^4-10^6 years. As the first real-world application of ATTA, we have determined the mean residence time of the old groundwater in the Nubian Aquifer located underneath the Sahara Desert. We will continue to improve the ATTA method and expand its applications in Earth sciences and nuclear non-proliferation.

Selected publications

• Tracing Noble Gas Radionuclides in the Environment. P. Collon, W. Kutschera and Z.-T. Lu. Ann. Rev. Nucl. Part. Sci., Vol. 54, 39 (2004). Nucl-ex/0402013.
• Laser spectroscopic determination of the 6He nuclear charge radius. L.-B. Wang et al. Phys. Rev. Lett. 93, 142501 (2004). Nucl-ex/0408008.
• Searches for stable strangelets in ordinary matter: overview and a recent example. Z.-T. Lu et al. Nuclear Physics A754, 361c (2004). Nucl-ex/0402015.
• One million year old groundwater in the Sahara revealed by krypton-81 and chlorine-36. N. C. Sturchio et al. Geophysical Res. Lett. 31, L05503 (2004). Physics/0402092.
• Search for anomalously heavy isotopes of helium in the Earth's atmosphere. P. Mueller et al. Phys. Rev. Lett. 92, 022501 (2004).
• Ultrasensitive isotope trace analyses with a magneto-optical trap. C.Y. Chen, Y.M. Li, K. Bailey, T.P. O'Connor, L. Young, Z.-T. Lu. Science 286, 1139 (1999).

Contact Info
Phone: (630)252-0584
Fax:(630)252-3903
Email:lu@anl.gov
URL:http://www.phy.anl.gov/mep/atta/

 

Available Research Areas for Undergraduates at Argonne Related to the RIA Project

Accelerator Physics for Heavy Ions and Radioactive Beams

The Physics Division at Argonne is the home of the world's first superconducting ion accelerator, the Argonne Tandem Linac Accelerator System, ATLAS. This accelerator is based on superconducting radio-frequency resonators and can accelerate any ion from ones as light as protons (atomic mass 1) to ones as heavy as uranium (atomic mass 238). ATLAS is a Department of Energy National User's Facility that provides high quality ion beams for basic research in nuclear science as described in the next section. The accelerator physics staff based at ATLAS is active in a variety of research and development projects. The topics include superconducting radio-frequency resonators, ion sources based on micro-wave heated plasmas, ion beam dynamics simulations, computer control systems, and other related topics. Much of the present research and development is directed towards the components of a proposed advanced accelerator called the Rare Isotope Accelerator, RIA. It is based on extensions of the present ATLAS technology and involves extending superconducting heavy ion linear accelerators to much higher energies and beam power. Topics currently being pursued for this new project also include the design and testing of high-power targets and associated ion sources for the production, extraction, and ionization of short-lived radioisotopes. Novel methods are also being developed for the efficient acceleration of these rare isotopes. Another area of active research is the development of advanced beam dynamics techniques for heavy ion accelerators and magnetic spectrographs.

Topics available for undergraduate research projects during the summer of 2005 include:

• High power production target and ion source development.
• Beam dynamics development for linear accelerators and magnetic spectrographs.
• Ion source testing and emittance measurements.

This list is not all inclusive and can be adapted depending on the interests of specific students after an orientation period at Argonne.

Description of RIA and additional links:

http://www.anl.gov/ria/ria.htm

 

For additional information please contact:
Allan Bernstein, Asst. Director, Physics Div.
Email bernstein@anl.gov or phone 630-252-6661