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The criticality safety divisions at Lawrence Livermore National Laboratory (LLNL) and Los Alamos National Laboratory (LANL), in partnership with Dr. Max Fratoni of UC Berkeley, taught the fourth annual nuclear criticality safety course during the fall 2021 semester at UC Berkeley. This course is part of a larger pipeline project designed to stimulate student interest in the field of criticality safety.
We present the analysis of the morphological shape of Berkeley 17, the oldest known open cluster (∼10 Gyr), using the probabilistic star counting of Pan-STARRS point sources, and confirm its core-tail shape, plus an antitail, previously detected with the 2MASS data. The stellar population, as diagnosed by the color–magnitude diagram and theoretical isochrones, shows many massive members in the clusters core, whereas there is a paucity of such members in both of the tails. This manifests mass segregation in this aged star cluster with the low-mass members being stripped away from the system. It has been claimed that Berkeley 17 is associated with an excessive number of blue straggler candidates. A comparison of nearby reference fields indicates that about half of these may be field contamination.
The Berkeley extreme ultraviolet/far ultraviolet shuttle telescope (BEST) will be launched on the Space Shuttle as part of the NASA UVX project. The Berkeley spectrometer will make observations of the cosmic diffuse background in the 600 to 1900 A band, with a spectral resolution of 10 A. The sensitivity and spectral resolution of the instrument make it ideal for the study of components of the interstellar medium in the 10 to the 4th power to 10 to the 6th power K range.
The Berkeley Extreme-ultraviolet Airglow Rocket Spectrometer (BEARS), a multiinstrument sounding rocket payload, made comprehensive measurements of the earth's dayglow. The primary instruments consisted of two near-normal Rowland mount spectrometers: one channel to measure several atomic oxygen features at high spectral resolution (about 1.5 A) in the band passes 980-1040 and 1300-1360 A, and the other to measure EUV dayglow and the solar EUV simultaneously in a much broader bandpass (250-1150 A) at moderate resolution (about 10 A). The payload also included a hydrogen Lyman-alpha photometer to monitor the solar irradiance and goecoronal emissions. The instrument was calibrated at the EUV calibration facility at the University of California at Berkeley, and was subsequently launched successfully on September 30, 1988 aboard a four-stage experimental sounding rocket, Black Brant XII flight 12.041 WT. The calibration procedure and resulting data are presented.
Vince Battaglia leads a behind-the-scenes tour of Berkeley Lab's BATT, the Batteries for Advanced Transportation Technologies Program he leads, where researchers aim to improve batteries upon which the range, efficiency, and power of tomorrow's electric cars will depend. This is the first in a forthcoming series of videos taking viewers into the laboratories and research facilities that members of the public rarely get to see.
This brochure provides an overview of the challenges and successes of Berkeley, CA, a 2007 Solar America City awardee, on the path toward becoming a solar-powered community. Accomplishments, case studies, key lessons learned, and local resource information are given.
Susannah Tringe, who leads the Metagenome Program at the Department of Energy's Joint Genome Institute (JGI), a collaboration in which Berkeley Lab plays a leading role, takes us behind the scenes to show how DNA from unknown wild microbes is extracted and analyzed to see what role they play in the carbon cycle. Tringe collects samples of microbial communities living in the wetland muck of the Sacramento-San Joaquin River Delta, organisms that can determine how these wetlands store or release carbon.
This is the First Annual Berkeley Lab Cultural Festival, sponsored by the Lab-Wide Diversity and Inclusion Council subcommittee.
In this follow-up "Ask Berkeley Lab" video, energy efficiency expert Iain Walker answers some of your questions about home energy efficiency. How do you monitor which appliances use the most energy? Should you replace your old windows? Are photovoltaic systems worth the cost? What to do about a leaky house? And what's the single biggest energy user in your home? Watch the video to get the answers to these and more questions.
Access to synchrotron X-ray facilities has become an important aspect for many disciplines in experimental Earth science. This is especially important for studies that rely on probing samples in situ under natural conditions different from the ones found at the surface of the Earth. The non-ambient condition Earth science program at the Advanced Light Source (ALS), Lawrence Berkeley National Laboratory, offers a variety of tools utilizing the infra-red and hard X-ray spectrum that allow Earth scientists to probe Earth and environmental materials at variable conditions of pressure, stress, temperature, atmospheric composition, and humidity. These facilities are important tools for the user community in that they offer not only considerable capacity (non-ambient condition diffraction) but also complementary (IR spectroscopy, microtomography), and in some cases unique (Laue microdiffraction) instruments. The availability of the ALS’ in situ probes to the Earth science community grows especially critical during the ongoing dark time of the Advanced Photon Source in Chicago, which massively reduces available in situ synchrotron user time in North America.
A high repetition rate, MHz-class, high-brightness electron source is a key element in future high-repetition-rate x-ray free electron laser-based light sources. The VHF-gun, a novel low frequency radio-frequency gun, is the Lawrence Berkeley National Laboratory (LBNL) response to that need. The gun design is based on a normal conducting, single cell cavity resonating at 186 MHz in the VHF band and capable of continuous wave operation while still delivering the high accelerating fields at the cathode required for the high brightness performance. The VHF-gun was fabricated and successfully commissioned in the framework of the Advanced Photo-injector EXperiment, an injector built at LBNL to demonstrate the capability of the gun to deliver the required beam quality. In conclusion, the basis for the selection of the VHF-gun technology, novel design features, and fabrication techniques are described.
The very-high-frequency gun (VHF-Gun) is a new concept photo-injector developed and built at the Lawrence Berkeley National Laboratory (LBNL) for generating high-brightness electron beams capable of driving X-ray free electron lasers (FELs) at MHz-class repetition rates. The gun that purposely uses established and mature radiofrequency and mechanical technologies has demonstrated over the last many years the capability of reliably operating in continuous wave mode at the design accelerating fields and required vacuum and mechanical performance. The conclusions of VHF-Gun technology demonstration were reported elsewhere [Sannibale et al., Phys. Rev. Spec. Top.-Accel. Beams 15, 103501 (2012)]; here in this work, we provide and analyze examples of the experimental results of the first high-brightness beam tests performed at the Advanced Photo-injector EXperiment test facility at LBNL that demonstrated the gun capability of delivering the beam quality required for driving high repetition rate X-ray FELs.
Synchrotron-radiation-based Fourier transform infrared (SR-FTIR or sFTIR) facilities worldwide are probing both live cells and tissues non-destructively under native-like conditions. From Spectroscopic data such as those acquired through the Berkeley Synchrotron Infrared Structural Biology (BSISB) program, spatially and temporally resolved chemical information of molecular classes are obtained. However, these infrared data lack chemical specificity for precise and accurate species identification. Here, high-resolution mass spectrometry (MS) directly contrasts with these IR data attributes in its ability to provide more specific identification of the full range of molecules at the cost of sample destruction.
We present the detection of directional muon beams produced using a PW laser facility at the Lawrence Berkeley National Laboratory. The muon source is a multi-GeV electron beam generated in a laser-plasma accelerator interacting with a high- converter target. The GeV photons resulting from the interaction are converted into a high-flux, directional muon beam via pair production. By employing scintillators to capture delayed events, we were able to identify the produced muons and characterize the source. Using theoretical knowledge of the muon production process combined with simulations that are in excellent agreement with the experiments, we demonstrate that laser-plasma accelerators have the capability of generating electron beams with characteristics suitable to produce GeV-scale muons that offer unique advantages with respect to the cosmic background. Laser-plasma-accelerator-based muon sources can therefore enhance muon imaging applications thanks to their compactness, directionality, and high yields, which reduce the exposure time by orders of magnitude compared to cosmic ray muons. Using the eant4-based simulation code we developed to gain insight into the experimental results, we can design future experiments and applications based on LPA-generated muons.
In Hadzimehmedovicet al.[Phys. Rev. C 84, 035204 (2011)] we have used the Zagreb realization of Carnegie-Melon-Berkeley coupled-channel, unitary model as a tool for extracting pole positions from the world collection of partial-wave data, with the aim of eliminating model dependence in pole-search procedures. In order that the method is sensible, we in this paper discuss the stability of the method with respect to the strong variation of different model ingredients. We show that the Zagreb CMB procedure is very stable with strong variation of the model assumptions and that it can reliably predict the pole positions of the fitted partial-wave amplitudes.
© 2019 SPIE. A 0.5-NA extreme ultraviolet micro-field exposure tool has been installed and commissioned at beamline 12.0.1.4 of the Advanced Light Source synchrotron facility at Lawrence Berkeley National Laboratory. Commissioning has demonstrated a patterning resolution of 13 nm half-pitch with annular 0.35-0.55 illumination; a patterning resolution of 8 nm half-pitch with annular 0.1-0.2 illumination; critical dimension (CD) uniformity of 0.7 nm 1σ on 16 nm nominal CD across 80% of the 200 um x 30 um aberration corrected field of view; aerial image vibration relative to the wafer of 0.75 nn RMS and focus control and focus stepping better than 15 nm.
This software comprises a portable, open-source implementation of a runtime library to support applications written in the Unified Parallel C (UPC) language. This library implements the UPC-specific functionality, including shared-memory allocation and distributed locks. The network-dependent functionality is implemented as a thin wrapper around the separate GASNet (Global-Address Space Networking) library, which is required for operation. This software implements the "Berkeley UPC Runtime Specification", which is targeted by at least four separate UPC compiler front-ends. The implementation is highly portable and runs over hardware ranging from laptops to custom supercomputers. An external library is required for certain local memory allocation operations; a well-defined interface allows for multiple implementations of this library, but at present the "umalloc" library from LBNL is the only compatible implementation.
This program is a portable, open-source, compiler for the UPC language. It is based on the Open64 framework and has extensive support for optimizations. This compiler operates by translating UPC into ANSI/ISO C for compilation by a native compiler and linking with the UPC Runtime Library. This design eases portability to both shared- and distributed-memory parallel architectures. For proper operation it requires the "Berkeley Unified Parallel C (UPC) Runtime Library" and its dependencies.