The Advanced Photon Source
a U.S. Department of Energy Office of Science User Facility

APSUO Bylaws

The Advanced Photon Source User Organization Bylaws  

This set of bylaws defines the membership, responsibilities, structure, and function of the Advanced Photon Source Users Organization (APSUO) and the APSUO Steering Committee.


The Advanced Photon Source Users Organization is responsible for advising the Associate Laboratory Director (ALD) for Photon Sciences in the following areas:

  • The Organization will serve as an advocacy group for the Advanced Photon Source (APS) user community and the APS facility.
  • The Organization will provide advice to the ALD on matters affecting the user community.
  • The Organization will assure good communication between the APS user community and the APS management.

Users Organization Membership

Membership is automatically granted to all badged users of the Advanced Photon Source.

Users Organization Steering Committee

The Steering Committee is charged with conducting the business of the APSUO. In general, the Steering Committee shall have up to 13 regular members, consisting of the Chair, Vice Chair, Past Chair, and up to 10 other regular members. The regular members of the Steering Committee must not be a current member of the APS staff. Each regular member has a three-year term, except for the Past Chair who may have up to a four-year term on the Steering Committee. Steering Committee members may be re-elected. The Steering Committee shall also include a position for a graduate student or postdoctoral fellow, if elected within two years of completing Ph.D. This position shall have a two-year term. All committee members are voting positions.

Four members shall be elected by the APSUO members each year, except in years when the student/postdoctoral fellow position is being filled, when up to five members may be elected. In case of resignation, death, or disability of a Steering Committee member, a replacement will be appointed by the Steering Committee to complete the term: the candidate from the immediately preceding election slate who received the highest number of votes but was not elected.  This appointed member may stand for re-election.

Steering Committee members will be elected to the APSUO Steering Committee through an electronic voting procedure conducted at the time of the annual Users Meeting. The open election period shall precede the Users Meeting by no less than two weeks and will close at the Users Meeting. All APSUO members are eligible to vote. 

The Steering Committee is responsible for facilitating a slate of candidates via a call for nominees and providing advance notice of the election to the APSUO membership. Any APSUO member may nominate candidates or self-nominate. Candidates must be APSUO members at the time of election. The candidates shall possess the highest personal and professional ethics, integrity, and values, and be committed to representing the interests of APSUO and APS mission and values. The candidates must be willing to devote sufficient time to fulfilling their duties and responsibilities, shall they be elected.

To promote representation of smaller interest groups, a weighted system of voting shall be used. Each ballot may select the number of candidates that equals to the number of expected vacancies, with the first choice assigned a number that equals to the number of expected vacancies, the second choice assigned a number that equals to the number of expected vacancies minus one, and so on. Tie votes shall be decided by a coin toss.

Student/postdoc member shall be elected in conjunction with the regular member election as needed.


The officers of the APSUO Steering Committee shall include.

  1. The Chair: The Chair shall serve for one year and enforce due observance of the rules and perform duties as directed by the Steering Committee and as the office may require. To assure continuity, the Chair shall continue to serve on the Steering Committee as Past Chair for a subsequent one-year term in an advisory role to the current Chair. If the Past Chair has already finished a three-year term, the Past Chair will remain as a voting member of the Steering Committee until the following Users Meeting.
  2. The Vice Chair: The Vice Chair shall serve for one year and be elected by the voting members of the Steering Committee after the Users Meeting. The Vice Chair shall be responsible for organizing the scientific program for the next Users Meeting. At that Users Meeting, the Vice-Chair will become the Chair. The Vice Chair shall stand in for the Chair if the Chair is unavailable.

Officers' terms on the Steering Committee shall be extended as needed to perform the above services.


Should the Chair resign, the current Vice Chair shall assume the responsibility of Chair for the remainder of the term, and then serve in the normal sequence of succession. The Steering Committee shall elect a replacement for Vice Chair. Any other vacancy on the Steering Committee shall be filled following procedures specified in the Users Organization Steering Committee section of APSUO Bylaws.



  1. The APSUO Steering Committee, in collaboration with Photon Sciences Directorate, shall organize an annual Users Meeting. The APSUO Steering Committee shall be responsible for the programs of the Users Meetings. APSUO members shall receive appropriate advance notice of the Users Meetings.
  2. The APSUO Steering Committee shall meet at intervals of approximately three months, with no fewer than four regular meetings per year, one of them in combination with the Users Meeting. Argonne National Laboratory will be responsible for providing administrative and financial support for these regular meetings as needed.
  3. Additional APSUO Steering Committee meetings may be called at the Chair’s discretion or by a majority of the APSUO Steering Committee.
  4. Announcement of all meetings shall be made in advance to all APSUO Steering Committee members.
  5. Minutes of all APSUO Steering Committee meetings shall be recorded by the User Office Liaison present. After approval by the APSUO Steering Committee, the minutes shall be made available to members of APSUO upon request. 
  6. The APSUO Steering Committee shall be responsible for collecting nominations for APSUO Awards and selecting the Awardees.


A quorum of the APSUO Steering Committee requires the presence of at least half of the members, which must include either the Chair or Vice-Chair or both. Issues are voted upon and decided by the majority of the members present. In case of a tie, the Chair has the deciding vote.


Proposed changes to the Bylaws shall be presented by the Steering Committee to the APSUO membership with facility access approval within the past 5 years, who will cast votes through electronic means. An open voting period of no less than two weeks is required. These bylaws shall be amended by a favorable vote of two-thirds of ballots cast.

  • Revision 5
  • Adopted February 8, 2021
  • Fan Zhang, Chair, APSUO

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