# Presentation: 211946

## Outline of the Report

- I. 		A Confluence of Scientific Opportunities: Why Invest Now in Theory and Computation in the Basic Energy Sciences?
- II.		The Unity of Theory and Computation in the Basic Energy Sciences
- III.	BES Community Input and Assessment
- IV. 	Emerging Themes in BES: Complexity and Control
- V. 	Connecting Theory with Experiment in BES: Accelerating Discoveries and Furthering Understanding
- VI.	The Resources Essential for Success in the BES Theory Enterprise
- VII.	Findings and Recommendations

## Subcommittee concern:

- Balance between tabletop science and large facilities

## Connection (?) of the Theory Program with the large BES Facilities

- APS, ALS, NSLS, IPNS, LANSCE, HFIR, ...
- All have little or no associated theory program
- Users must find theoretical collaborators who are willing and already funded to work on their problems.

**Need stronger coupling of theory and computation with experiments at BES facilities.  -  Committee and Testimony**

## New Major Experimental Facilities

- Theoretical Support and Guidance  -
- Strategy for Success: *Asking the Right Questions and Understanding the Answers*

- 5 Nanoscience Facilities
- Spallation Neutron Source
- Linac Coherent Light Source
- Motivation to integrate theory partnership in the planning stages:  to accelerate discoveries and understanding; to enhance efficacy of facilities.

## Outline of the Report

- I. 		A Confluence of Scientific Opportunities: Why Invest Now in Theory and Computation in the Basic Energy Sciences?
- II.		The Unity of Theory and Computation in the Basic Energy Sciences
- III.	BES Community Input and Assessment
- IV. 	Emerging Themes in BES: Complexity and Control
- V. 	Connecting Theory with Experiment in BES: Accelerating Discoveries and Furthering Understanding
- VI.	**The Resources Essential for Success in the BES Theory Enterprise**
- VII.	Findings and Recommendations

## The Resources Essential for Success in the BES Theory and Computation Enterprise

- The Spectrum of Computational Resources
- New Styles of Support: Scientific Codes as Shared Instruments
- Human Resources:  Training Future Generations

## The Spectrum of Computational Resources “Branscomb pyramid”

## Role of Algorithms and Software

## New Styles of Support: Scientific Codes as Shared Instruments

**Spallation Neutron Source (SNS) ****Center for Nanophase Materials Science (CNMS)****   **

**NERSC **
**3,328-processor **
**5 teraflop/s**

- Facility

- Instrumentation** **

**User Community**

## Human Resources:  Training Future Generations

- “Students and postdoctoral fellows are the lifeblood of Basic Energy Sciences”
- Need to attract and support bright young people
- ...mostly found in University single-PI groups.

## Supplemental

- Findings and Recommendations from V and VI.

## A Broad Recommendation Regarding Coupling Theory and Experimental Programs in BES 

**RECOMMENDATION:** BES should undertake a major new thrust to significantly augment its theoretical and computational programs coupled to experimental research at its major facilities.
- When new experimental facilities (e.g., LCLS) are proposed by BES, the associated theory and computational efforts should be incorporated from the outset.
- BES should seek funding for upgrades to the existing facilities, with the support of their respective user groups, for theory efforts to be associated with the experimental efforts at those facilities. Such theory efforts could include personnel, resources, and support for a shared software infrastructure.
- Increased investments in the BES programs are needed to build theory efforts that strongly couple to science at existing facilities.

## Findings on the Coupling of Theory to Experiment in BES

**FINDING:** The recent trend in certain BES programs, for example at the Nanoscale Science Research Centers, on increasing the coupling of theoretical and experimental activities is both proper and timely.
**FINDING:** At the existing light and neutron sources, there appears to be little conscious or systematic effort by BES to stimulate and support, with targeted resources, theoretical partnerships with experimental efforts. We believe that this situation puts at risk DOE’s ability to extract the maximum scientific benefit from those facilities.
**FINDING:** At the facilities currently under construction (the Nanoscale Science Research Centers and the Spallation Neutron Source), an effort has been made to incorporate theory into the planning for the facilities. However, these efforts are incomplete and uneven in scope.

## Finding and Recommendation on Computational Resources

**FINDING:** Progress in the BES theory enterprise requires increased access to the entire spectrum of computational resources contemplated by the Office of Science for the next ten years: (A) BES is ready for and requires access to leadership-scale computing to perform calculations that cannot be done elsewhere. (B) A large amount of essential BES computation falls between the leadership scale and the desktop scale.
**RECOMMENDATION:** BES should become strongly engaged with the DOE Office of Advanced Scientific Computing Research to ensure that large amounts of time on terascale capacity facilities are available to the BES scientific community. Also, BES should consider supporting some of this capacity with local institutional computing, while ensuring that demand at the higher end of computing power is supplied by larger facilities.

## Finding and Recommendation on an Additional New Style of Support for Theory and Computation

**FINDING:** The current lack of support for the development and maintenance of shared scientific software diminishes the scientific impact of the BES-supported theory community and creates an obstacle to the effective exploitation of high-end computing resources and facilities.
**RECOMMENDATION:** BES should support the development and maintenance of scientific codes in the disciplines in its portfolio, just as it now funds the development of shared beamlines at its experimental facilities, thereby creating new scientific capabilities for the nation. Such investments will also be critical in allowing BES researchers to take full advantage of the capabilities of DOE’s leadership-class computing facilities.