Seeking Postdoctoral Researcher or Research & Development Scientist (26-941) Part-time

Postdoctoral Researcher or Research & Development Scientist

Accelerator Group RIKEN Nishina Center for Accelerator-Based Science (Group Director: Osamu Kamigaito)

As the driving force of the RIKEN RI Beam Factory (RIBF) — the world's most advanced heavy-ion accelerator facility — the Accelerator Group is dedicated to the technical development, operation, and maintenance required to provide a diverse range of high-intensity heavy-ion beams with long-term stability.

The Next-Generation Heavy-Ion Accelerator System Development Team is advancing the RIBF Upgrade Program to further increase beam intensity at the RI Beam Factory (RIBF), focusing on the development of the Charge Stripper Ring (CSR). The CSR is a unique accelerator in which an ion beam circulates in the ring while repeatedly undergoing charge exchange until the desired charge state is reached. Our work covers the simultaneous and stable circulation of multi-charge-state beams, gas charge-exchange schemes, and beam control techniques that exploit charge exchange. We also explore a future extension of the CSR concept toward a heavy-ion internal-target ring, referred to as “Chreostron.”

Job title: Postdoctoral Researcher or Research & Development Scientist, one position

Postdoctoral Researcher: In principle, Postdoctoral Researcher is defined as those who obtained a doctoral degree no more than 5 years ago. Receive training and guidance from senior staff; conduct research projects and other activities for Programs or equivalent.

Research & Development Scientist: Research & Development Scientist must have over 5 years of research or practical experience. Conduct technical development research projects and other activities.

The successful candidate will be engaged in a technical development research project for the development and construction of the CSR (Charge Stripper Ring) planned at the RIKEN RI Beam Factory (RIBF), with a view toward its future operation and further upgrading. The CSR is a unique complex accelerator system designed to increase beam intensity by circulating heavy-ion beams in multiple charge states simultaneously in the ring and repeatedly using an internal charge stripper. The main duties will involve part of the device development related to the design and construction of the CSR, mainly in one of the following areas: the charge stripper system, electromagnet systems, vacuum systems, or beam diagnostic systems. After completion of the system, the successful candidate will also undertake research and development to ensure stable operation and improve performance, as well as maintenance of the equipment. These activities will include the application of artificial intelligence and data-science methods to CSR beam tuning and operational optimization.

Qualification: Individuals who have already earned a Ph.D. in a related field, or who are expected to earn a Ph.D. by the hiring date

Work location: RIKEN Wako Campus (2-1 Hirosawa, Wako, Saitama 351-0198) RIKEN may order the employee to change work locations, if necessary.

Salary and Benefits: A one-year fixed-term employment contract, renewable based on evaluation, up to 5 years for Postdoctoral Researcher or up to 7 years for Research & Development Scientist from initial date of hire. RIKEN may adjust the above maximum period of renewability based on a) the employee's abilities, work load at the time of contract completion, performance and work attitude and b) the continuation of the employee's center, laboratory or project and RIKEN's management situation and budget at the time. In principle, employment contracts will not be renewed for individuals older than 70 years old. There will be an interim review around the 3rd year (Postdoctoral Researcher), 5th year (Research & Development Scientist). In principle, the first two months of employment are considered a trial period. Salary will be an annual salary based on experience, ability, and performance, and will consist of a base salary and a variable salary. The variable salary will be determined each fiscal year based on experience, ability, and performance. Discretionary work, commuting and housing allowances will be provided. Social insurance will be applied. The total amount of monthly discretionary work allowance and monthly salary at the time of hiring will be 382,610 JPY or more for Postdoctoral Researcher and 448,990 JPY or more for Research & Development Scientist. RIKEN has a telecommuting system, but this position requires attendance at the work location. Therefore, the telecommuting system is not available for this position, in principle. This position falls under the specialized duties discretionary work system; one working day will be calculated as 7 hours and 30 minutes. Days off include public holidays, New Year's holidays (Dec. 29 – Jan 3), and RIKEN Foundation Day. Paid leave includes annual paid leave (up to 20 days depending on the month of employment), special paid leave (caring for a sick child, family nursing care, etc.), and work life balance holidays (up to 7 days depending on the month of employment). There are also additional leave systems such as maternity leave, childcare leave, and family nursing care leave. Smoking is entirely prohibited on site. These and other provisions are in accordance with RIKEN regulations. Mandatory membership in the RIKEN Mutual Benefit Society (RIKEN Kyosaikai). Eligible to apply for the MEXT Grants-in-Aid for Scientific Research (Kakenhi).

Application and required documents: Complete CV or CV

• Write the RIKEN job ad number “26-941”, indicated in the parentheses next to the job title, in the RIKEN job ad number section in the upper right corner of your CV.

List of research achievement and publications. (Including ResearcherID or Google Scholar ID, if available) A letter of recommendation from the current supervisor (If unavailable, a letter from a substitute reference will be acceptable.)

• Please specify the referee's contact information (Name, affiliation, job title, phone number, and email address)

Summary of major achievements to date and research proposal in future (two pages A4 sized paper, respectively) Agreement on handling of personal information (Handling of personal information based on the Hiring Privacy Policy, the General Data Protection Regulation, and the UK General Data Protection Regulation) Please review the following web page before submitting the consent form.:

• * Hiring Privacy Policy
• * The General Data Protection Regulation (GDPR)
• * Regulation (EU) 2016/679 of the European Parliament and of the Council of 27 April 2016 on the protection of natural persons with regard to the processing of personal data and on the free movement of such data (United Kingdom General Data Protection Regulation)

How to apply: The above documents, except the letters of recommendation, should be combined into a single ZIP file and uploaded to the following link: Accelerator Group Upload Folder. The file name of the ZIP should contain your contact email address. After you upload the ZIP file, please let us (kamigait@riken.jp) know the file name of the upload file. Recommendation letters must be directly submitted from the referees to the following link with the file name *Accelerator Group [applicant's name] (recommendation letters)*. Please specify the applicant's name and referee's name and contact information in the recommendation letters. Accelerator Group Upload Folder. Note: All the submitted documents will not be returned.

Deadline: Application must arrive by October 30, 2026 (JST)

Handling Personal Data: Submitted documents are strictly protected under the RIKEN Privacy Policy and will be used only for the purpose of applicant screening at RIKEN. Personal information will not be disclosed, transferred or loaned to a third party under any circumstances without just cause.

Selection process: Application screening and interview for selected applicants

Notification of hiring decision: The notification of hiring decision (conditional offer of employment) regarding this selection shall be carried out through the presentation of an Employment Contract or a Conditional Offer of Employment issued by RIKEN.

Start of Employment: April 1, 2027 (Negotiable)

Contact Information: Accelerator Group RIKEN Nishina Center for Accelerator-Based Science Group Director: Osamu Kamigaito Email: kamigait@riken.jp Next-Generation Heavy-Ion Accelerator Systems Development Team Team Leader: Hiroshi Imao Email: imao@riken.jp For inquiries, please send an email.