Near field science with the Roman High Latitude Wide Area Survey

The Nancy Grace Roman Space Telescope’s High Latitude Wide Area Survey (HLWAS) will enable transformative studies of the Milky Way and nearby galaxies with its near-infrared observations of Milky Way satellites, stellar streams, globular cluster populations, and extragalactic stellar halos. These structures, all of which lie in the footprint of the HLWAS, will:

• trace the gravitational imprint of dark matter substructure, revealing the hidden architecture of our cosmic neighborhood;
• disentangle the hierarchical assembly of nearby galaxies through precise metallicity measurements of individual resolved stars, placing the Milky Way’s history in context;
• reconstruct the star formation histories of faint satellite galaxies and extragalactic stellar halos, delineating the gravitational interplay between baryonic and dark matter.

These topics represent just a fraction of the anticipated scientific legacy of the Roman HLWAS for near-field cosmology. With the release of the fiducial survey strategy from the ROTAC, and the upcoming first Roman call, now is the time to explore and advocate for the awesome potential of Roman’s flagship survey.

This 3-day workshop will convene members of the High Latitude Imaging Survey Cosmology Project Infrastructure Team, responsible for the HLWAS core science, and the community of near-field cosmologists to:

• understand how choices in executing the survey will affect its usefulness for near-field science,
• make concrete recommendations for maximizing this usefulness in the context of the survey’s core goals, and
• plan analyses of the first year of HLWAS data for near-field science.

Activities will include:

• Invited talks highlighting Roman’s near-field science potential, with updates from teams on survey design, data pipelines, and preparatory science.
• Dedicated discussions to refine scientific strategies, prioritize key goals, and establish community expectations for data products.
• Tutorials on Roman image simulation, mock data, and the Roman Research Nexus.

This gathering aims to foster collaboration between infrastructure teams and researchers, ensuring the community is prepared to harness Roman’s data upon its 2026 launch. 

We are committed to facilitating a meeting that is productive and enjoyable for everyone. In support of this, all invited speakers and participants are expected to review in advance and to adhere to the meeting code of conduct and all attendees will be held accountable to these stated principles.

Thanks to everyone who completed the form. We are happy to announce that this meeting has no registration fee. Attendance confirmation requests were sent on July 10, 2025, and registration closed on July 31, 2025. If you have filled out the form and not received any email, or for any late registration request, please contact us via the provided contact form.

Invited speakers will be added to the program as they are confirmed.

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Day 1

Morning – Introduction to the HLWAS

8:30-9 Coffee, Pastries & Registration

9-10:20 Invited talks

• 9-9:10 Welcome and motivation – Robyn Sanderson
• 9:10-9:30 Roman status & capabilities – Julie McEnery
• 9:30-10 Overview of HLWAS committee document supporting ROTAC plan – David Weinberg
• 10-10:20 Discussion: Data products for HLWAS

10:20-10:40 Coffee break

10:40-11:20 Small group Q&A between PIT and near-field researchers
11:20-11:50 Report from small groups

12-13:30 Lunch

Afternoon – The Milky Way/Local Group

13:30- Invited Talks

• 13:30-13:50 Overview of useful things we’ve learned from RINGS/WINGS – Ben Williams
• 13:50-14:10 Astrometry with Roman – Robyn Sanderson
• 14:10-14:30 Roman-Gaia crossmatching for astrometry – Kevin McKinnon
• 14:30-14:50 Dwarf galaxies with Roman HLWAS – Burcin Mutlu-Pakdil
• 14:50-15:10 Transient searches with Roman – Dave Sand

15:10-15:30 Coffee

15:30-16:15 Small Group Discussion: What should be observed with the first epoch of the HLWAS? 

16:15-16:45 Report from small groups

16:45-17:00 Summary & Logistics

~18-20h Workshop dinner

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Day 2

Morning – The Local Volume

9-9:30 Coffee, Pastries & Registration

Invited Talks

• 9:30-9:50 The Local Volume in DESI, LSST, and Euclid – Aaron Romanowsky
• 9:50-10:10 Stellar halos in the Local Volume – Eric Bell
• 10:10-10:30 SphereX synergy – Olivier Doré

10:40-11 Coffee Break

11-11:40 Discussion: Synergies

11:40-12 Summary

12-13:30 Lunch

Afternoon – Roman tools for near-field science

• 13:30-14:30 Roman Research Nexus and the Roman image simulators
  • Nexus – Vihang Mehta
  • STIPS – Justin Otor
  • Roman I-Sim – Tyler Desjardins
• 14:30-14:50 Py-ananke – Adrien Thob
• 14:50-15:10 Image simulation for low surface brightness – Jiaxuan Li 李嘉轩
• 15:10-15:30 Crowded-field photometry for Roman – Adam Smercina

15:30-15:50 Coffee

15:50-16 Organization: into small groups for practice, & unconference for Friday

16++ Practice with Roman tools

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Day 3

Morning – followup

We will schedule additional discussions and/or “unconference” sessions as needed.
Coffee and workspace will be available in the venue.
Meeting ends at lunchtime

Interested in participating remotely? Register at https://bit.ly/hlwas_remote.

• Talks will be broadcast live and recordings/slides posted to this page, unless otherwise requested by the speaker.
• Discussions will not have a hybrid component, but notes from the sessions will be posted, as will oral summaries.
• Software workshops will not have a hybrid component, but we will post information about alternatives as it becomes available.

(Hidden-block)

The organizers are committed to making this meeting productive and enjoyable for everyone, regardless of gender, sexual orientation, disability, physical appearance, body size, race, national origin or religion. We will not tolerate harassment of participants in any form. Please review this code of conduct before stating your interest for this meeting.

Please follow these guidelines:

Behave professionally. Harassment, sexist, racist, or exclusionary comments or jokes are not appropriate. Harassment includes sustained disruption of talks or other events, inappropriate physical contact, sexual attention or innuendo, deliberate intimidation, stalking, and photography or recording of an individual without consent. It also includes offensive comments directed towards an individual or group.

All communication should be appropriate for a professional audience including people of many different backgrounds. Sexual language and imagery is not appropriate.  Be kind to others. Do not insult or put down other attendees. Critique ideas, not people.

If participants wish to share photos or contents of talks/slides of any attendee or speaker on social media, we ask that they first get permission.

Participants asked to stop any inappropriate behavior are expected to comply immediately. Attendees violating these rules may be asked to leave the event at the sole discretion of the organizers.

Any participant who wishes to report a violation of this policy is asked to speak, in confidence, to any member of the SOC, or report anonymously from the meeting website.

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This code of conduct is based on the “London Code of Conduct”, as originally designed for the conference “Accurate Astrophysics. Correct Cosmology”, held in London in July 2015.  The London Code of Conduct was adapted with permission by Andrew Pontzen and Hiranya Peiris from a document by Software Carpentry, which itself derives from original Creative Commons documents by PyCon and Geek Feminism.

Our code of conduct aligns with the principles outlined in NASA’s guidelines, which can be found at: https://cor.gsfc.nasa.gov/docs/HQ/NASA-Astrophysics-Statement-of-Principles-Nov2022.pdf 

If you have any questions, please email us at near-field-roman-hlwas@googlegroups.com or contact us below and we’ll respond promptly

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SOC: Benjamin Williams (UW), Robyn Sanderson (UPenn), Adrien Thob (UPenn), Lee Armus (IPAC; local host) on behalf of the High Latitude Imaging Survey Cosmology PIT.