BEGIN:VCALENDAR
VERSION:2.0
CALSCALE:GREGORIAN
PRODID:UW-Madison-Physics-Events
BEGIN:VEVENT
SEQUENCE:0
UID:UW-Physics-Event-4780
DTSTART:20180312T170000Z
DURATION:PT1H0M0S
DTSTAMP:20260419T035149Z
LAST-MODIFIED:20180228T210431Z
LOCATION:2241 Chamberlin Hall
SUMMARY:X-ray sources from laser-plasma acceleration: development and 
 applications for high energy density sciences\, Plasma Physics (Physic
 s/ECE/NE 922) Seminar\, Félicie Albert\, Lawrence Livermore National 
 Laboratory
DESCRIPTION:Bright sources of x-rays\, such as synchrotrons and x-ray 
 free electron lasers (XFEL) are transformational<br>
\ntools for many 
 fields of science. They are used for biology\, material science\, medi
 cine\, or industry. Such<br>
\nsources rely on conventional particle a
 ccelerators\, where electrons are accelerated to gigaelectronvolts<br>
 
\n(GeV) energies. The accelerating particles are also wiggled in magn
 etic structures to emit x-ray radiation<br>
\nthat is commonly used fo
 r molecular crystallography\, fluorescence studies\, chemical analysis
 \, medical<br>
\nimaging\, and many other applications. One of the dra
 wbacks of synchrotrons and XFELs is their size and<br>
\ncost\, becaus
 e electric field gradients are limited to about a few 10s of MeV/M in 
 conventional<br>
\naccelerators.<br>
\nThis seminar will review partic
 le acceleration in laser-driven plasmas as an alternative to generate 
 x-rays.<br>
\nA plasma is an ionized medium that can sustain electrica
 l fields many orders of magnitude higher than<br>
\nthat in convention
 al radiofrequency accelerator structures. When short\, intense laser p
 ulses are focused<br>
\ninto a gas\, it produces electron plasma waves
  in which electrons can be trapped and accelerated to GeV<br>
\nenergi
 es. This process\, laser-wakefield acceleration (LWFA)\, is analogous 
 to a surfer being propelled by<br>
\nan ocean wave. Betatron x-ray rad
 iation\, driven by electrons from laser-wakefield acceleration\, has<b
 r>
\nunique properties that are analogous to synchrotron radiation\, w
 ith a 1000-fold shorter pulse. This source<br>
\nis produced when rela
 tivistic electrons oscillate during the LWFA process.<br>
\nAn importa
 nt use of x-rays from laser plasma accelerators we will discuss is in 
 High Energy Density<br>
\n(HED) science. This field uses large laser a
 nd x-ray free electron laser facilities to create in the laboratory<br
 >
\nextreme conditions of temperatures and pressures that are usually 
 found in the interiors of stars and<br>
\nplanets. To diagnose such ex
 treme states of matter\, the development of efficient\, versatile and 
 fast (subpicosecond<br>
\nscale) x-ray probes has become essential. In
  these experiments\, x-ray photons can pass<br>
\nthrough dense materi
 al\, and absorption of the x-rays can be directly measured\, via spect
 roscopy or<br>
\nimaging\, to inform scientists about the temperature 
 and density of the targets being studied.<br>
\nWork performed under t
 he auspices of the U.S. Department of Energy by Lawrence Livermore Nat
 ional Laboratory<br>
\nunder contract DE-AC52-07NA27344\, supported by
  the LLNL LDRD program under tracking code 13-LW-076\,<br>
\n16-ERD-02
 4\, 16-ERD-041\, supported by the DOE Office of Fusion Energy Sciences
  under SCW 1476 and SCW<br>
\n1569\, and by the DOE Office of Science 
 Early Career Research Program under SCW 1575.
URL:https://www.physics.wisc.edu/events/?id=4780
END:VEVENT
END:VCALENDAR