The ALS-U project is a proposed upgrade to the Advanced Light Source (ALS) at Berkeley Lab that aims to deliver diffraction limited performance and an increase of the beam brightness by two orders of magnitude for soft x-rays compared to the current ALS facility. The storage ring design utilizes a nine-bend achromat lattice, with reverse bending magnets and on-axis swap-out injection from an accumulator ring. This paper will describe the preliminary plans for the installation of a new accumulator ring (AR) in the existing tunnel, and for the removal and replacement of the existing storage ring (SR). The AR will be installed during regular maintenance shutdowns while the ALS continues to operate. The current ALS will be shutdown for a nominal twelve month darktime period, consisting of 9 months of SR removal and installation activities, followed by three months of commissioning.

The ALS-U project to upgrade the Advanced Light Source to a multi bend achromat lattice received CD-1 approval in 2018 marking the end of its conceptual design phase. The ALS-U design promises to deliver diffraction limited performance in the soft x-ray range by lowering the horizontal emittance to about 70 pm rad resulting in two orders of magnitude brightness increase for soft x-rays compared to the current ALS. The design utilizes a nine bend achromat lattice, with reverse bending magnets and on-axis swap-out injection utilizing an accumulator ring. This paper presents recent design progress of the accelerator, as well as new results of the R&D program.

The Advanced Light Source (ALS) at Berkeley Lab remains one of the brightest sources for soft x-rays worldwide. A multiyear upgrade of the ALS is underway, which includes new and replacement x-ray beamlines, a replacement of many of the original insertion devices and many upgrades to the accelerator. The accelerator upgrade that affects the ALS performance most directly is the ALS brightness upgrade [1], which reduces the horizontal emittance from 6.3 to 2.0 nm (2.5 nm effective). Magnets for this upgrade were installed in late 2012 and early 2013 followed by user operation with the reduced emittance.

ALS has been upgraded by adding Top-Off Mode, a new mode of operation to the existing modes of Fill and Stored Beam. The Top-Off Mode permits injection of 1.9GeV electron beam into the Storage Ring, with the safety shutters open, once certain strict conditions are met and maintained. Top-Off Mode enables User operation without an interruption caused by mode switching between the Stored Beam Mode when safety shutters are open, to the Fill Mode with the safety shutters closed and back. The conditions necessary to permit Top-Off Mode are; stored beam is present, the energies are matched between the injector and storage ring, a select set of storage ring lattice magnets are operating at the correct current levels, and radiation losses are minimized. If certain combinations of these conditions are not met, a potentially dangerous condition of injecting electrons down a users beam line can exist. Therefore a system of mode control, energy match, lattice match and stored beam interlocks are needed to control the injected beam prohibiting potentially dangerous conditions. In this paper we will present the Top-Off Mode Beam Interlock system requirements, design, and operational parameters.

An upgrade of the Advanced Light Source to enable top-off operation has been completed during the last four years. The final work centered around radiation safety aspects, culminating in a systematic proof that top-off operation is equally safe as decaying beam operation. Commissioning and transition to full user operations happened in late 2008 and early 2009. Top-off operation at the ALS provides a very large increase in time-averaged brightness (by about a factor of 10) as well as improvements in beam stability. The following sections provide an overview of the radiation safety rationale, commissioning results, as well as experience in user operations.

The purpose of this document is to outline the Advanced Light Source (ALS) approach for preventing a radiation accident scenario on the ALS experimental floor due to top-off operation. The document will describe the potential risks, the analysis, and the resulting specifications for the controls.

There is substantial interest in the potential health effects of workplace flexibility; however, the literature linking flexibility to health is limited. The purpose of this study was to enhance understanding of the potential benefits of flexibility for employee health and well-being. Additionally, this study determines if this association is mediated by work-family balance. Results from longitudinal data obtained from a large multinational company showed that increased flexibility was associated with decreased sickness absence and work-related impairment and improved job commitment over a 1-year period. Furthermore, work-family balance partially mediated the effects of flexibility on impairment and job commitment but not sickness absence. This study strengthens the evidence base for the beneficial health effects of workplace flexibility and suggests that organizations benefit from building a culture of flexibility in the organization.

Objective: To examine the cross-sectional and longitudinal associations between workplace flexibility and health behaviors, and estimate the potential importance of flexibility for effective worksite health promotion programs. Method: Cross-sectional and longitudinal health risk appraisal data were obtained from US based employees of a multinational pharmaceutical company (n = 3193). Examined health behaviors were hours of sleep, physical activity frequency, health education seminar attendance, frequency of practicing personal resilience techniques, and self-appraised lifestyle. Self-reported flexibility in the workplace was the primary independent variable. Results: Each health behavior, except regular attendance in health education seminars, was positively related to perceived flexibility in cross-sectional analyses. Sleep and self-appraised lifestyle were significantly related to changes in perceived flexibility over time. Conclusions: Workplace flexibility may contribute to positive lifestyle behaviors, and may play an important role in effective worksite health promotion programs.

ALS, one of the first third generation synchrotron light sources which has been operating since 1993 at Berkeley Lab has been upgraded from its present operation scenario of injecting the 1.5 GeV electron beam from the Booster ring into the Storage ring every 8 hours, where it is accelerated to the final energy of 1.9 GeV, to full energy (1.9 GeV) injection from the Booster ring into the Storage ring every 3 seconds for filling and every 30-35 seconds for "Top-Off" mode. Additionally the beam current will be increased from the time averaged value of 250 mA to 500 mA to increase the brightness. In this paper we will present the final design of the Booster RF power source and control system upgrades and the performance results of the new ALS injector RF system set-up for Top-Off mode of operation.