A5030368821- Advanced X-ray Imaging Techniques
- Adaptive optics and wavefront sensing
- Advanced Frequency and Time Standards
- Geophysics and Sensor Technology
- Pulsars and Gravitational Waves Research
- Optical Systems and Laser Technology
- Spacecraft Design and Technology
- Geophysics and Gravity Measurements
- X-ray Spectroscopy and Fluorescence Analysis
- Radio Astronomy Observations and Technology
- Inertial Sensor and Navigation
- Advanced Measurement and Metrology Techniques
- Atomic and Subatomic Physics Research
- Spacecraft and Cryogenic Technologies
- Surface and Thin Film Phenomena
- Scientific Measurement and Uncertainty Evaluation
- Space Satellite Systems and Control
- Surface Roughness and Optical Measurements
- GNSS positioning and interference
- Spacecraft Dynamics and Control
- Superconducting Materials and Applications
- Scientific Research and Discoveries
- Heat Transfer and Boiling Studies
- Satellite Communication Systems
- Calibration and Measurement Techniques
Lawrence Berkeley National Laboratory
2020-2024
Stanford University
2015-2017
This article describes the development and testing of a novel, water-cooled, active optic mirror system (called "REAL: Resistive Element Adjustable Length") that combines cooling with applied auxiliary heating, tailored to spatial distribution thermal load generated by incident beam. technique is theoretically capable sub-nanometer surface figure error control even at high power density. Tests conducted in an optical metrology laboratory synchrotron X-ray beamlines showed ability maintain...
This paper presents a novel cantilevered liquid-nitrogen-cooled silicon mirror design for the first optic in new soft X-ray beamline that is being developed as part of Advanced Light Source Upgrade (ALS-U) (Lawrence Berkeley National Laboratory, USA). The optimized photon energies between 400 and 1400 eV with full polarization control. Calculations indicate that, without correction, this will achieve Strehl ratio greater than 0.85 entire energy ranges beamline. With correction achieved by...
We describe a new space gravitational wave observatory design called LAGRANGE that maintains all important LISA science at about half the cost and with reduced technical risk. It consists of three drag-free spacecraft in most stable geocentric formation, Earth-Moon L3, L4, L5 Lagrange points. Fixed antennas allow continuous contact Earth, solving problem communications bandwidth latency. A 70 mm diameter AuPt sphere 35 gap to its enclosure serves as single inertial reference per spacecraft,...
A realistic wave optics simulation method has been developed to study how wavefront distortions originating from heat load deformations can be corrected using adaptive X-ray optics. Several planned soft and tender insertion-device beamlines in the Advanced Light Source upgrade rely on a common design principle. flat, first mirror intercepts white beam; vertical focusing is provided by variable-line-space monochromator; horizontal comes single, pre-figured, mirror. variety of scenarios cope...
Abstract This report documents evaluation of simultaneous estimation multiple interfacial heat transfer coefficients (HTCs) using transient measurements from an experiment designed for steady-state operation. The design a mirror system directing X-rays under cryogenic conditions requires knowledge the HTC (contact conductance) between silicon and indium. An experimental apparatus was constructed to measure temperatures in stack five 7.62-mm thick pucks separated by 0.1-mm sheets indium,...
We discuss the potential for a small space mission to perform an advanced Kennedy-Thorndike test of Special Relativity using large and rapid velocity modulation available in low Earth orbit. An improvement factor ~100 over present ground results is expected, with additional 10 possible more technology.
A Drag-Free CubeSat mission has been proposed to demonstrate the feasibility of a Gravitational Reference Sensor (GRS) with an optical readout for 3 units (3U) spacecraft. purely drag-free object is defined by absence all external forces other than gravity, which are shielded In real case, TM will still be affected disturbances. Several them passively reduced design housing. This system thick-walled aluminium box that holds shadow sensors and shields TM. The housing effect on mechanical,...
The proposed space mission mini Space-Time Asymmetry Research (mSTAR) aims at a test of special relativity by performing clock-clock comparison experiment in low-Earth orbit. Using clocks with instabilies or below the 1·10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-15</sup> level orbit time, Kennedy-Thorndike coefficient will be measured an up to two orders magnitude higher accuracy than current limit set ground-based experiments. In...
This report presents testing of a prototype cantilevered liquid-nitrogen-cooled silicon mirror. mirror was designed to be the first for new soft X-ray beamlines built as part Advanced Light Source Upgrade. Test activities focused on fracture, heat transfer, modal response and distortion, indicated that functions intended.
Over the last three decades, an exceptionally good science case has been made for pursuing gravitational wave (GW) astronomy. This engendered a worldwide effort to detect extremely weak signals generated by expected sources. With next round of upgrades ground based instruments are likely make first detections sources, and new era astronomy will begin, possibly as early 2017. Inconveniently, due seismic noise baseline length issues, low frequency (<10Hz) part spectrum, where most interesting...
In this paper we provide an update on the development of a novel cantilevered-liquid-nitrogen-cooled-silicon mirror for new insertion device beamline included in Advanced Light Source Upgrade (ALS-U). The goals are to achieve diffraction limited performance, demonstrate reliability, minimize coolant flow induced vibration, and carbon contamination prevention cleaning techniques. summarize design requirements, system, prototype fabrication.
The thorough realization of the advantages new generation x-ray light sources, such as Upgraded Advanced Light Source (ALS˗U) under construction, requires near-perfect optics, capable delivering without significant degradation brightness and coherence. stringent requirements beamline optics drive state art in ex situ optical metrology. Here, we present results ongoing efforts at ALS X-Ray Optics Laboratory to develop a long trace profiler, LTP-2020. We discuss system design that incorporates...
In this paper we report on the modeling and characterization of transmission windows for in-situ interferometric measurements cryogenically cooled mirrors. Specifically, present a model temperature distribution strain in window, corresponding spatial dependence window's index refraction. We also experimental results which characterize effect measurement.
The mini Space Time Asymmetry Research (mSTAR) is a proposed space mission to perform an advanced Kennedy-Thorndike (KT) test of Special Relativity using the large and rapid velocity modulation available in low Earth orbit (LEO).The goal special relativity by performing clock-clock comparison experiment LEO, thereby testing boost dependence speed light.Clocks with stabilities better than 10 15 level at time will allow KT coefficient be measured up two orders magnitude higher accuracy current...
We describe the implementation of realistic, adaptive wavefront correction in high-brightness beamline simulations to study thermal deformation. Several planned soft x-ray and tender insertion-device beamlines Advanced Light Source upgrade, where preservation is paramount, rely on a common design principle.After studying performance 20-channel mirror prototype, at-wavelength with visible-light, we implemented shape-control algorithms software that are designed restore optimize focused beam...