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

User Administration

The APS User Office staff are in a hybrid work mode, with some staff in the office daily. All staff are available via e-mail during normal office hours.

APS User Office hours: 8:00 a.m. - 4:30 p.m., Monday-Friday

General inquiries:

From on-site phones, dial 2 and the last four numbers listed below.

Location: Building 401, ground floor (left of elevators)



Susan White-DePace

  • Manager, User Programs
  • Phone: 630-252-7172
  • Email:

Constance Vanni

  • Assistant Manager, User Programs
  • Phone: 630-252-0909
  • Email:

Jacki Flood

Jessi Krzemien

Kim Toerpe

  • User administration, general user proposals, Users Meeting
  • Phone: 630-252-1783
  • Email:

Tony Killelea

  • User check-in, training, user correspondence
  • Phone: 630-252-6974
  • Email:
Lauren Ambrose
  •  Financial user accounts
  •  Phone: 630-252-1244
  •  Fax: 630-252-9250
  •  Email:
Rebecca Sikes
  • Foreign visits and assignments, registrations
  •  Phone: 630-252-7858
  •  Email:

Nathan Rogers



Mailing Address
  • Advanced Photon Source
    Argonne National Laboratory
    9700 S. Cass Avenue
    Building 401
    Lemont, IL 60439



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