AAC2020 welcomes international participants; this page gives some practical information.
Attendees from many countries will be eligible for the Visa Waiver Program (VWP).
To take advantage of VWP, you need to register with the Electronic System for Travel Authorization (ESTA) before your trip.
Consumer Protection Notice: Third parties who charge money for a "service" related to ESTA are not actually capable of expediting approval. The link shown above takes you to the official US Government site, which explains the process and provides everything you need to enroll online in ESTA for a small fee.
In general you will need either a machine-readable passport or an e-passport containing a chip in order to visit the US without a visa. Most countries have been issuing them for the last several years. Here is the US Department of Homeland Security's illustrated guide to the eligible generations of passports.
Canada, Mexico, and Bermuda
The US has special arrangements with adjoining nations and Bermuda.
Citizens of countries not participating in the Visa Waiver Program would request a Business (B-1) visa at the nearest U.S. Consulate. Call them to set up an appointment. When you go to the Consulate, take a copy of your invitation and (if you have already registered) your Conference Registration Notice, along with your valid passport. We urge you to apply as soon as you can, because the process can take time.
Usually you would apply for a B-1 visa as a nonsponsored attendee of an international scientific workshop. The B-2 visa is for tourism and might be appropriate for companions who are not attending the conference.
The Travel site at the U.S. Department of State is the official source for information on visas and everything else you should know about visiting the US. Be sure to apply early!
Visa Letters and Other Helpful Documentation
As this is a by-invitation workshop, your invitation letter should serve for visa purposes. These letters do not imply financial support.
If you are giving a talk or poster, you will receive an acceptance letter when your abstract is in the system. Only submitting and presenting authors, not other co-authors, get an acceptance letter.
Copies of your round-trip itinerary, a printout of your paid registration, evidence of your stature as a scholar (such as your curriculum vitae, including publications list), and evidence of your binding ties to your home country are also known to be helpful in obtaining a visa.
Further helpful advice can be found on the National Academies website.
Local Contact
If you need to specify a "local contact" or "host" for your visa or institutional paperwork, we suggest
Wes Tabler
Administrative coordinator, Advanced Accelerator Concepts Workshop 2020
LBNL, 1 Cyclotron Road, Mailstop 71R0259
Berkeley, CA 94720 USA
+1 510.486.6710 voice, +1 510.486.7981 fax
Monterey, like all of California, is in the Pacific Time Zone, and AAC2020 will be held during the months of Daylight Savings Time, so the UTC (GMT) offset is -7.