Title: Talbot–Lau x-ray deflectometry phase-retrieval methods for electron density diagnostics in high-energy density experiments

Abstract

Talbot–Lau x-ray interferometry uses incoherent x-ray sources to measure refraction index changes in matter. These measurements can provide accurate electron density mapping through phase retrieval. An adaptation of the interferometer has been developed in order to meet the specific requirements of high-energy density experiments. This adaptation is known as a moiré deflectometer, which allows for single-shot capabilities in the form of interferometric fringe patterns. The moiré x-ray deflectometry technique requires a set of object and reference images in order to provide electron density maps, which can be costly in the high-energy density environment. In particular, synthetic reference phase images obtained ex situ through a phase-scan procedure, can provide a feasible solution. To test this procedure, an object phasemap was retrieved from a single-shot moiré image obtained from a plasma-produced x-ray source. A reference phase map was then obtained from phase-stepping measurements using a continuous x-ray tube source in a small laboratory setting. Ultimately, the two phase maps were used to retrieve an electron density map. A comparison of the moiré and phase-stepping phase-retrieval methods was performed to evaluate single-exposure plasma electron density mapping for high-energy density and other transient plasma experiments. It was found that a combination of phase-retrieval methodsmore » can deliver accurate refraction angle mapping. Once x-ray backlighter quality is optimized, the ex situ method is expected to deliver electron density mapping with improved resolution. The steps necessary for improved diagnostic performance are discussed.« less

Authors:

Valdivia, Maria Pia ^[1]; Stutman, Dan ^[1]; Stoeckl, Christian ^[2]; Mileham, Chad ^[2]; Begishev, Ildar A. ^[2]; Bromage, Jake ^[2]; Regan, Sean P. ^[2]

---

+ Show Author Affiliations

1. Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Physics and Astronomy
2. Univ. of Rochester, NY (United States). Lab. for Laser Energetics

Publication Date:

Wed Jan 03 00:00:00 EST 2018

Research Org.:

Johns Hopkins Univ., Baltimore, MD (United States); Univ. of Rochester, NY (United States)

Sponsoring Org.:

USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:

1430099

Alternate Identifier(s):

OSTI ID: 1415326

Grant/Contract Number:  

NA0002955

Resource Type:

Accepted Manuscript

Journal Name:

Applied Optics

Additional Journal Information:

Journal Volume: 57; Journal Issue: 2; Journal ID: ISSN 1559-128X

Publisher:

Optical Society of America

Country of Publication:

United States

Language:

English

Subject:

70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY