# Presentation: 017383

## LCLS Update 

***Eric A. Rohlfing***
***BESAC Meeting***
***August 2, 2001***

***Office of Basic Energy Sciences***
***Office of Science, U.S. Department of Energy***

## Scientific Case for the LCLS

**   ****Reviews**
- Presented to and discussed by BESAC in October 2000
- Unanimous vote to recommend that BES approve CD0,  ***contingent***** **upon positive external peer review
- External peer review completed in November 2000

-   **“****LCLS:  The First Experiments”**
- Scientific case directly tied to decision on proceeding with LCLS construction (Critical Decision 0 - Conceptual Design)
- Aimed at defining (in some detail) the first classes of experiments that would be mounted on the LCLS
- Basis for experimental requirements for the LCLS CDR
- Assembled through the LCLS Scientific Advisory Committee

**Reviews not sufficiently strong to proceed with CD0**

## Path Forward in Feb. 2001

* *** ****BES delayed approval of CD0**
- Strong support for the LCLS project, but....
- Scientific case and level of “community” support not yet sufficient

**BES Workshop on Scientific Applications of Ultrafast, Intense, Coherent X-Rays**
**Organizers:**  Eric Rohlfing and Pedro Montano, BES
**Focus:**  scientific applications of source with LCLS specifications with emphasis on ultrafast dynamics, nonlinear optics, x-ray imaging
**Participants:**  20-25 scientists; LCLS “veterans” with newcomers
**Logistics:**  May 4-5, 2001; Wardman Park Marriott, Washington, DC
**Output:**  report that complements and broadens LCLS scientific case

## BES Workshop Agenda

**Friday, May 4**
- 8:15 am**	***Introductory Remarks*
- 	**Eric Rohlfing**
**Session I****	**Chair:**  Eric Rohlfing**
- 8:30 am	 *LCLS Technical Overview*
**	****John Galayda**
- 	*Discussion of* “*LCLS:  The First Experiments”*
- 9:05 am 	*Chemistry, Condensed Matter and Biology*
**	****Jo Stohr **
- 9:35 am	*Atomic and Plasma Science*
**	****Phil Bucksbaum**
- 10:00 am	*X-Ray Laser Physics*
**	****Jerry Hastings**
- 10:20 am	*Generation of Ultra-short X-Ray Pulses*
**	****Claudio Pelligrini**
- 10:30 am		**** Break ****
- 11:00 am	*Femtosecond X-Ray Diffraction with Table-Top *
*	**Laser-driven* *K-alpha Sources*
**	****Craig Siders**
- 11:30 am	*Ultrafast Science with Femtosecond X-ray Pulses*
**	****Robert Schoenlein**
**Session II****	**Chair:**  Pedro Montano **
- 1:30 pm	*Small-Scale Coherent Short-Wavelength Sources*
**	****Henry Kapteyn**
- 2:00 pm	*Producing and Probing Unique Plasmas with the LCLS using Atomic *
*	**Cluster Targets*
- 	**Todd Ditmire**
- 2:30 pm	*Time-Resolved X-ray Spectroscopies; Nonlinear Response Functions and **	**Liouville-Space Pathways*
- 	**Shaul Mukamel**
- 3:00 pm	*New Ordered States of Dense Excited Matter*
- 	**Charles Rhodes**
- 3:30 pm	**** Break ****
- 4:00 pm	*Open Discussions*
- 	**All Participants**

**	****	****Saturday, May 5**
**Session III****	**Chair:**  Eric Rohlfing **
- 8:30 am	*LCLS Applications in Microscopy*
**	****Chris Jacobsen**
- 9:00 am	*Prospects for Correlation Spectroscopy at the LCLS*
**	****Simon Mochrie**
- 9:30 am	*Time Domain Structural Studies of Chemical Reactions *
*	**Using Pulsed X-Rays*
**	****James Norris**
- 10:00 am		**** Break ****
- 10:30 am	**Discussion Session I:*****  Ultrafast Phenomena***
**	****Leader:  Steve Leone**
- 1:30 pm	**Discussion Session II:*****  Coherence and Imaging***
**	****Leader:  Simon Mochrie**
- 3:00 pm	**** Break ****
- 3:30 pm	**Discussion Session III:*****  Atomic Physics/Nonlinear Optics***
**	****Leader:  Phil Bucksbaum**
- 5:00 pm	**** Adjourn ****

## Highlights of BES Workshop

**  ****Shorter LCLS pulse still highly desirable**
- To extend x-ray probes into the time regime of atomic motion in molecules and solids
- To “beat” destruction of the electronic and molecular structure in imaging experiments
- There are realistic proposals for shortening the LCLS pulse

**More clearly defined the areas of science that LCLS (baseline operation) can potentially impact**
- Multiple core level excitation or multiphoton processes in atoms
- Volumetric excitation of nanoscale matter by x-rays
- Structural determinations for large biomolecules or nanocyrstals via x-ray imaging
- Dynamics in condensed phases

## Impact of BES Workshop

**  ****Decision to proceed with CD-0 in June, 2001**
- CD-0 signed by the Acting Director, Office of Science
- Preliminary project budget validation completed (TEC = $175M)

**Realization that the scientific community has been sufficiently canvassed to develop the best scientific case**
- No more workshops!  (at least for a while)
**BUT!**  Scientific program for the LCLS will continue to evolve and be very strongly coupled to advances in XFEL physics

**LCLS collaboration now authorized to prepare Conceptual Design Report (CDR)**
- With good progress and funding availability, project engineering and design could start in FY03 and construction in FY04

## LCLS CD-0

**CD-0, Approve Mission Need**
**for the**
**Linac Coherent Light Source (LCLS)**
**Office of Basic Energy Sciences**
**Office of Science**
**A.  Justification of Mission Need**
- 1.  Office of Basic Energy Sciences Program Mission
- The mission of the Office of Science is “To advance basic research and the instruments of science that are the foundations for DOE’s applied missions, a base for U.S. technology innovation, and a source of remarkable insights into our physical and biological world and the nature of matter and energy.”  The Linac Coherent Light Source (LCLS) project is a unique opportunity for a major advance in carrying out that mission.
- The Office of Basic Energy Sciences (BES) within the DOE Office of Science currently operates four major synchrotron facilities:  the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory, the Stanford Synchrotron Radiation Laboratory (SSRL) at the Stanford Linear Accelerator Center (SLAC), the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory and the Advanced Photon Source (APS) at Argonne National Laboratory.  These four facilities provide world-class X-ray probes of matter to an enormous user community that spans a broad range of the physical and biological sciences.  BES is dedicated to the stewardship of the current light sources, as evidenced by the ongoing upgrades to SSRL, and to advancing the state-of-the art in X-ray probes of matter through the development of next-generation sources and instruments.
- In the early 1990s, it became clear that the next-generation X-ray light source would be based on a linac-driven, x-ray free electron laser (XFEL).  As early as 1992, workshops began to better define the properties of such an XFEL and the science that would be enabled.  In 1994, the National Research Council published a study, *Free Electron Lasers and Other Advanced Sources of Light, Scientific Research Opportunities*, that reached the conclusion that FELs were not competitive with conventional lasers for scientific applications *except* in the X-ray region.