February 28, 2013
Final Review Report
Initiative Research Scientist
Song Changyong
Kohei Tamao, Chair
Initiative Research Scientist Program Promotion & Review Committee
This is a report on the final review, conducted by email and carried out in accordancewith Article 13 (Evaluation) of the RIKEN Regulations for the Initiative Research Unit
Program, of the Song Initiative Research Unit, which is scheduled to end its 5-year term onFebruary 28, 2013.
Research topic: Atomic Resolution Coherent X-ray Diffraction Imaging
utilizing the Japan XFEL
Term: March 1, 2008 to February 28, 2013

Final email review
1. Date: February 26, 2013
2. Review committee:
Chair: Kohei Tamao, Director, RIKEN ASI
Deputy Chair : Masaki Takada, Deputy Director, RIKEN SPring-8 CenterMembers: Yoshiyuki Amemiya, Professor, Graduate School of Frontier
Science, University of Tokyo：Masayoshi Nakasato, Professor, Department of Physics, Faculty ofScience and Technology, Keio University：Katsumi Midorikawa, Deputy Director, ASI

3. Review process:
Reviewers were asked to comment by email on the unit’s final report, submitted onJanuary 31, 2013. Reviewers were also given a list of review criteria and a selfevaluation as reference. The reviewers’ comments were summarized in a one-page
report.
4. Review results:
The final review report and comments of individual reviewers are attached.

February 26, 2013
Final Review Report
Initiative Research Scientist
Song Changyong

Kohei Tamao, Chair
Initiative Research Scientist Program
Promotion & Review Committee
This document summarizes the comments provided by peer reviewers on the project,“Atomic Resolution Coherent X-ray Diffraction Imaging utilizing the Japan XFEL”
conducted by the Song Changyong Initiative Research Unit. This unit is scheduled to end its
research activity on February 28, 2013.The reviewers are listed separately in the appendix.
The Song Initiative Research Unit was launched within the RIKEN Frontier Research
System (FRS) in March 2008, and immediately thereafter moved to the RIKEN AdvancedScience Institute, which was established in April 2008. In October 2009, the unit was moved
again to the RIKEN SPring-8 Center (RSC). Over the past five years, this unit has worked toachieve coherent X-ray diffraction imaging (CDI) for atomic resolution, making full use ofSPring-8 and the RIKEN XFEL facility SACLA. The unit has a number of majorachievements, among them:(1) New wet-CDI imaging technique enabling high-resolution imaging of live cells(2) Multiple-application x-ray imaging chamber (MAXIC) for single-particle imaging,pump-probe ultrafast imaging, nano-crystallography, and other diverse applications
making use of the SACLA X--‐ray pulses and coherence.
(3)

Liquid-jet and aerodynamic-jet injectors enabling single-particle CDI structural analysis(4) New CDI scheme for surface and thin film observation(5) Fixed target, single-particle CDI imaging

The originality, creativity and academic significance of these successful achievements
have already been highly evaluated in the unit’s 2011 Interim Review, and the unit has
made further progress since then. In addition, Initiative Researcher Song has chaired anumber of international workshops for SACLA utilization, expanding the user network andleading the way for research making use of this key national technology. The lab’s
management was also highly evaluated at that time and we have seen no need to add newevaluation criteria in this regard.
This Initiative Research Unit has consistently achieved excellent results, despite its
frequent change in affiliation from one RIKEN organization to another, and we are pleased
that Song will stay at RIKEN as a team leader within the RSC where he will be able tocontinue his work in research and development.
The comments of the individual review committee members which were submitted to
the review committee chair are attached to this report. These comments are based on theReview Criteria distributed to the committee members prior to the review.

[Appendices]
Comments from individual review committee members● Dr. C Song has made effort on the research program of x-ray diffraction imaging at
SACLA (single-shot imaging), Spring-8(3D bio-imaging) and SCSS.
He constructed computer facilities with reconstruction algorithms for rapid data analysis
and versatile imaging platform at single-pulse SACLA by introducing Multiple Applications
X-ray Imaging Chamber (MAGIC) in order to host many domestic and foreign users.
He also developed liquid jet single particle-injector with 3 microns diameter, which is
required for live cell imaging and nano-crystallography. He is currently developing gas-jetinjector.
In addition to the construction of the above infrastructure, he has performed thefollowing experiments and published the results in the scientific journals.
1. 3D imaging of a mouse nucleus with a resolution of better than 50 nm at SPring-8,
which will be a basis for the 3D imaging of human nuclei and immune-labeled humanchromosomes.
2. Demonstration of single-shot diffraction of DNA molecules using SCSS, including theassessment of FEL radiation damage for the first time.
3. Proof-of-principle experiments on single-shot diffraction imaging in reflection
geometry at SCSS with an aim to transplant the technique at SACLA for high resolution.
4. CDI experiment of wet specimens with a resolution of better than 40 nm, which will bea basis for high-resolution bio-imaging in native conditions.
5. R&D experiment of ultrafast pump-probe x-ray diffraction imaging at SACLA using
MAXIC, with an aim to pursue ultrafast phenomena in materials science and life science.
The above achievements are very important so as to make the best use of SACLA in the
coming very near future. They also reflect Dr. Song’s good leadership and governance of histeam.
I am convinced that Dr. C. Song has played an important role in the research anddevelopment of CDI for use with SACLA and hope that his research will be further
developed in collaboration with users at SACLA.
● 1. Scientific achievement
The mission of Song Initiative Research Unit (IRU) is the application of coherent X-ray
diffraction imaging (CXDI) for non-crystalline particles using coherent X-rays provided bySPring-8 and SACLA. Through 5-years project, the IRU has achieved significant advancesin the methodology and application of CXDI, and provided key techniques to promote
cutting-edge researches using SPring-8 and SACLA. The research results from the IRU
open new venues in structural analyses of non-crystalline materials, which are never
crystallized, from biological and material science field.
For instance, visualization of cells at a resolution of better than 50 nm under wet
condition is a great advance in the CXDI field. Until mid-term review, Dr. Song succeededin the visualization of spore yeast cell at a resolution of 50 nm. However, the sample wasdried under non-physiological condition. Because biologists require the structures of cellsand molecules in fully hydrated condition, Dr. Song and his collaborators developed aspecial CXDI chamber dedicated for experiments under wet condition necessary to maintaintheir functional structures. The equipment works well, and the research group succeeds inthe visualization of some cellular imaging. The results will open new science andtechnology based on CXDI imaging of biological non-crystalline objects. Furthermore, Dr.
Song developed the MAXIC chamber for single-shot diffraction imaging using XFEL pulse
from SACLA. This chamber can mount the sample particles fixed on membrane films,single-particle liquid injectors developed in collaboration with Professor Mafune of The
University of Tokyo.
Taking his contribution to the CXDI field, it is clear that Dr. Song is one of leaders in theworld as indicated by the number of invited lectures in international symposium on CXDI
(19 in 5 years), the six publications in top journals and one invited review paper. The
experimental techniques including data analysis proposed by the IRU are unique and would
be one of worldwide standard of CXDI researches.
2. Management
The IRU unit consists of PI, one research scientist, two post-doctoral researchers, one
IPA student and one part-time technical assistant. Dr. Song recruited the research scientist
and two post-doctoral fellows, who were expert in X-ray diffraction imaging usingsynchrotron X-ray. As a result of these recruitment, the well organized role-sharing
arrangement in the IRU was possible in carrying out researches including collaborativeprojects with laboratories outside RIKEN. In addition, Dr. Song received competitive grants,
Kakenhi from JSPS (2010-2011) and CELA/GIST fund of Korea (2011-2012).
The Unit has several collaborative projects with university laboratories of domestic andoversea countries. Regarding the application of well-established CXDI technique, Dr. Songpromotes collaborative projects with sample suppliers to extend the possibilities of CXDI.
On the other hand, for novel experimental techniques requiring R&D, the IRU interacts
with the professionals. For instance, the collaboration with professor Mafune of theUniversity of Tokyo would be a key to develop the liquid injector method in SACLA
single-shot CXDI experiments. Thus, two types of collaboration promoted by Dr. Song arequite effective to extend the methodology and application of CXDI.
3. Summary
In the past five years, Dr. Song and his staffs performed outstanding developments ofequipments and data processing, CXDI experiments for wet biological samples andpromotions of several collaborative projects in CXDI. The research progresses are being
made timely, properly and nicely with high impacts. Thus, it is concluded that the Song IRU
has made great contribution to the development and application of CXDI at SPring8/SACLA.
● Dr. C Song engaged in researches on the x-ray diffraction imaging using synchrotron
radiation at UCLA. Making full use of his carrier, he has been developing a variety ofinfrastructures including x-ray diffraction imaging devices specialized for SACLA, Spring-8
and EUV-FEL, computer facilities for data acquisition and analysis, and multiple-application
X-ray imaging chamber to further pursue his research. It should be specially noted that thosedevices are contributing to the advancement of x-ray imaging research by SACLA andSPring-8. Especially, a single-particle injector is highly evaluated because this injector isindispensable for single-shot diffraction imaging and nano crystallography by SACLA,
which are expected to bring a breakthrough for biology and drug design.
In parallel to the construction of infrastructures, he has achieved three remarkable research
results, which are・3D imaging with 50 nm resolution
・Wet-CDI of fully hydrated biological specimens
・Single-shot diffraction imaging by FEL and assessment of radiation damage
These achievements are timely and published in high-impact, prestigious journals. He
presented 19 invited talks in his tenure. These facts prove his high performance and excellent
ability.
I am convinced that Dr. C. Song plays a key role of the future use of SACLA for x-ray
imaging and hope that he continues his research activity at Spring-8 facility.