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In this issue:
SLAC First in Hard X-Ray Lasers
Dorfan Today: Planning the Future of Particle Physics
Public Lecture: Joanne Hewett

SLAC Today

Monday - April 24, 2006

(Image - LCLS)
The LCLS will use free electron laser (FEL) technology.

SLAC First in Hard X-Ray Lasers

Research and equipment at SLAC enable it to host the world's first hard x-ray laser. In the Linac Coherent Light Source (LCLS), state-of-the-art technology will harness photons with the shortest wavelength ever corralled into coherence.

Soft x-ray lasers harness photons with wavelengths greater than one nanometer. SLAC will use hard x-rays, whose one nanometer and smaller wavelengths possess higher energies.

In a traditional laser, electrons release photons as they drop to a lower energy orbital around their atoms. Those found in grocery store scanners and laser pointers typically use light within the visible spectrum and require electrons to bounce between mirrors millions of times until they radiate light in phase. But by doing so, the efficiency of the process dwindles.

X-ray lasers escape these constraints by using free electron laser (FEL) technology that uses an electron beam rather then electrons bound to atomic or molecular states.  Read more...

(Director's Column - Dorfan Today)

Planning the Future
of Particle Physics

Competition for U.S. federal funds to support major scientific endeavors has never been keener. Each major field of science must present compelling scientific arguments, backed by sharp-edged peer review and strong community support, to justify their federal budgets. This is as it should be—"entitlement" is no way to run a scientific railroad.

We are in the midst of two major elements in the future planning for the field of particle physics. Last week the Particle Physics Project Prioritization Panel (P5) met both at Fermilab and at SLAC and this week's major event is the release of the final report of the National Academies Committee on Elementary Particle Physics in the 21st Century ("EPP2010") at a public briefing on Wednesday, April 26, 2006.

The Particle Physics Project Prioritization Panel (P5), a subpanel of the High Energy Physics Advisory Panel, has been charged by its parent bodies the Department of Energy and the National Science Foundation with developing a detailed roadmap and a set of priorities for the field of particle physics. The roadmap will cover roughly the next 10 years and should address priorities both for the support of ongoing programs and the investments needed near-term for new projects. Thus the role of P5 is very important to our future and it is our obligation to help P5 to be successful. P5 is made up of eighteen physicists from the US, one from Europe and one from Japan and includes SLAC's Joanne Hewett and Tor Raubenheimer. P5 will submit a detailed report to DOE and NSF by September 2006.  Read more...

Public Lecture:
Space - The Hunt for Hidden Dimensions

Extra dimensions of space may be present in our universe. Their discovery would dramatically change our view of the cosmos and would prompt many questions. How do they hide? What is their shape? How many are there? How big are they? Do particles and forces feel their presence?

In Tuesday's public lecture, SLAC's Joanne Hewett will explain the concept of dimensions and show that current theoretical models predict the existence of extra spatial dimensions which could be in the discovery reach of present and near-term experiments. The manner by which these additional dimensions reveal their existence will be described. Searches for modifications of the gravitational force, astrophysical effects, and collider signatures already constrain the size of extra dimensions and will be summarized. Once new dimensions are discovered, the technology by which the above questions can be answered will be discussed.

Hewett took her first physics class as a sophomore in college, was immediately hooked, and embarked on a career of performing esoteric theoretical calculations. Her research probes the fundamental nature of space, matter, and energy, where she most enjoys devising experimental tests for preposterous theoretical models. She is eagerly awaiting the next round of high energy accelerator experiments to see which theories are present in our universe.

She will present "Space: The Hunt for Hidden Dimensions" on Tuesday, April 25 at 7:30 pm in Panofsky Auditorium. All are welcome to attend. More information...

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