2014 ATLAS User’s Meeting: May 15-16, 2014

Dear Colleagues,

The ATLAS accelerator complex at Argonne National Laboratory restarted operation after an extended shutdown to complete its intensity and efficiency upgrade. This upgrade project consisted of a reconfigured injection line and a positive-ion injector that now includes a high-intensity CW RFQ for initial acceleration. In addition, a major reconfiguration of the booster section was also part of the project. A new cryostat with state-of-the-art cavities has been installed and a number of older cavities were consolidated. These modifications, together with additional changes to the beam transport, result in a rejuvenated ATLAS facility capable of handling much higher beam intensities. Operation of the low-energy section of the accelerator, including the new RFQ and the positive ion injector, restarted in mid-January. The full accelerator, including the totally reconfigured booster section, restarted operation in March and has been reliably delivering beam to experiments, including a number of GRETINA experiments, since then. In addition, a new 1.7 Ci Californium source is being installed at CARIBU. This source should greatly improve the extracted yields for neutron-rich exotic beams.

The ATLAS facility made available to the Users after this upgrade has significantly improved capabilities. As a result, it is expected that the research program will evolve to take full advantage of new physics opportunities with a suitable suite of experimental equipment. Significant work has already gone into improvements of existing experimental systems (e.g.; digital Gammasphere, digital FMA, new HELIOS detectors) and into developing new equipment (AGFA, AIRIS) through fruitful collaborations between Users and in-house staff. At this point, it is important to gather further input from the ATLAS User community. To this end, the Executive Committee of the ATLAS Users group and ATLAS management are organizing a User Meeting to take place at ANL on May 15-16, 2014. The meeting will focus on delineating the goals of the physics program for the next decade, and on defining the experimental equipment required to meet these objectives. An updated strategic plan for ATLAS will be developed as a result. Contributions from the ATLAS user community will play an important role in the formation of this strategic plan.

Information on the two-day meeting is now posted at https://www.phy.anl.gov/atlas/workshop14/, together with a preliminary program and registration forms. The meeting will be mostly devoted to discussions on the path forward for the main physics programs at ATLAS and on the required experimental equipment. The meeting schedule includes a number of discussion sessions where the main physics topics in the ATLAS program will be covered. Groups or individuals are encouraged to bring forward new initiatives (physics and experimental equipment) and, to this end, are encouraged to contact the session conveners as soon as possible so that the required discussion time can be incorporated in the program. The session conveners are listed below, together with the e-mail addresses where they can be reached:

- Nuclear Structure: P. Fallon (pfallon@lbl.gov), W. Reviol (reviol@wustl.edu), M.P. Carpenter (carpenter@phy.anl.gov)
- Single-particle structure and reactions: S. Pain (stevenpain@nuclearemail.org), B. Kay (Kay@phy.anl.gov)
- Astrophysics: C. Deibel (deibel@phys.lsu.edu), J. Clark (jclark@phy.anl.gov)
- Fundamental Interactions: N. Scielzo (scielzo1@llnl.gov), P. Mueller (pmueller@anl.gov)
- Applications: P. Collon (Philippe.A.Collon.1@nd.edu), E. McCutchan (mccutchan@bnl.gov)

Also available on the meeting website is a directory containing one page descriptions of a number of new experimental and machine initiatives that provide their basic characteristics and capabilities. These are a starting point for gathering information about some of the possibilities for future experiments with these devices at ATLAS.

We are counting on your presence and active participation to this workshop as it will define the strategic plan guiding the future of the ATLAS facility for the next decade. We look forward to seeing you all at ANL in May.

Alan Wuosmaa, Chair of the ATLAS Users Executive Committee
Guy Savard, Scientific Director of ATLAS