WAMTAS | Beiwa

Workshop on Angular Momentum Transfer Across Scales

Motivation

Angular momentum is present and is transferred across a large variety of scales during the formation and evolution of stars. In recent years, a new generation of observations and simulations have enabled us to study with unprecedented detail processes where an adequate description of angular momentum is crucial, e.g., formation of binaries/multiples and protostellar jets. At the same time, rotation plays a critical role in the mixing processes which take place during the evolution of stars, and significantly affect the evolution, fate and yields of stars, and in particular of massive stars. The main goal of this workshop is to bring together experts on star formation and stellar evolution across several scales: clouds, disks/outflows and stellar interiors, in order to discuss recent advances in understanding angular momentum transfer, and how to better integrate our communities to better address the remaining challenges of this topic.

Participation

Due to the limited space available (max. 60 people) and the diverse target audiences of the workshop, participation is by invitation only. A limited number of slots will be offered to contact persons from different international research groups, and the contact persons will have the freedom to propose participants (both junior and/or senior) that best represent the work done within the group.

Once final, the list of participants will be published here.

Schedule

There will be three sessions, covering different scales: clouds, disks-jets, and stellar evolution, including the role of multiples in every scale. An excursion to one of Costa Rica's touristic destinations is planned for one of the days of the conference. Every effort possible will be made to accommodate the schedule such that flight departures for the direct Europe-bound flights on Friday, 26th of February are possible in case you want to take them. We strongly recommend visiting our many national parks ( https://www.sinac.go.cr ) in the weeks prior and after the conference (please take into account long travel times by road within Costa Rica). More information will follow.

Once final, the schedule will be published here.

Costs

As this is an invitation-only conference, every effort possible is being made not to ask for a participation fee. Coffee breaks are covered by the organization, but not lunches. The (optional) excursion will likely require a participation fee. More details will follow.

Venue and dates

The workshop will take place from the 22nd until the 26th of February 2027 in the Mini-Auditorium #1, Faculty of Engineering (FIng), Finca 2, University of Costa Rica (San José, Costa Rica).

Getting here

The closest airport is SJO (Juan Santamaría International Airport serving San José, Costa Rica, and located in Alajuela). There are direct flights from several cities in Europe and North America. Here some examples (not sponsored, please check with every company):

Madrid - SJO: all-year daily direct flights (Iberia)
Frankfurt - SJO: all-year direct flights, planned to be 5 times per week around the conference time (Lufthansa)
Zürich - SJO: all-year direct flights, 3 times per week (Edelweiss)
Paris CDG - SJO: all-year direct flights, there are even two flights per day during some days around the conference time (Air France)
London LHR - SJO: seasonal direct flights almost every day between October and March (British Airways)
Amsterdam - SJO: all-year direct flights, 5 times per week around the conference time (KLM)
Mexico City - SJO: multiple departures per day (Aeromexico, Avianca)
New York EWR - SJO: multiple departures per day (United Airlines)
Toronto - SJO: multiple departures per day (Air Canada, Air Transat, Porter)
Montreal - SJO: several departures per week (Air Canada, Air Transat)
San Francisco, Los Angeles - SJO: one flight per day (United Airlines, Alaska Airlines)
From Japan, we suggest flights with a stop in the US (Dallas, LAX) or via Mexico (NRT-MEX-SJO for the outbound flight and SJO-MEX-MTY-NRT on the return flight, Aeromexico). There are plans for flights via Panama, but they are unlikely to be ready for the time of the conference.

Please note that there is another international airport in Costa Rica, the Guanacaste Airport (LIR). Travel times by road between the two airports can reach up to 6 hours, in part due to ongoing construction work (scheduled to finish around the time of the conference, but unconfirmed).

General visa information: according to the latest info from the Immigration Office (17th of Nov 2025), passport holders of the following countries are exempt from visa:

Germany, Andorra, Argentina, Australia, Austria, Bahamas, Barbados, Belgium, Brazil, Bulgaria, Canada, Croatia, Chile, Cyprus, Denmark, United Arab Emirates, Slovakia, Slovenia, Spain, Qatar, United States of America, Estonia, Finland, France, Hungary, Ireland, Iceland, Israel, Italy, Japan, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Mexico, Montenegro, Norway, New Zealand, Netherlands (Holland), Panama, Paraguay, Poland, Portugal, Principality of Monaco, San Marino, Peru, Puerto Rico, Serbia, South Africa, United Kingdom of Great Britain and Northern Ireland, Czech Republic, Republic of Korea (South Korea), Hellenic Republic (Greece), Romania, Holy See (Vatican City), Singapore, Sweden, Switzerland, Trinidad and Tobago, Ukraine, Uruguay, Antigua and Barbuda, Belize, Bolivia, Dominica, El Salvador, Brunei, Russia, Philippines, Fiji, Grenada, Guatemala, Guyana, Honduras, Northern Mariana Islands, Marshall Islands, Solomon Islands, Kiribati, Malaysia, Maldives, Mauritius, Micronesia (Federated States), Nauru, Palau, Kingdom of Tonga, Samoa, Saint Kitts and Nevis, Saint Vincent and the Grenadines, Saint Lucia, São Tomé and Príncipe, Seychelles, Suriname, Taiwan (Region), Tuvalu, Turkey, Vanuatu.

Passport holders of other countries (such as Colombia, Ecuador, Armenia, Nicaragua, India, People's Republic of China and Venezuela) might need a visa to enter Costa Rica. However, there is a very important exception: if you hold a residence permit or certain visa types from the US or Canada, or if you hold a residence permit or certain visa types from the UK or any country in the Schengen Area, then you don't need a visa to visit Costa Rica for the conference. Official information is found in https://migracion.go.cr/visas/ (in Spanish).

Detailed instructions on how to reach the venue in San José will follow.

Scientific organizing committee

	André Oliva University of Costa Rica andre.oliva @ ucr.ac.cr
	Rolf Kuiper University of Duisburg-Essen (Germany)

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