Detailed Programme

18 – 22 May 2026 · Lorentz Center@Omega, Leiden

Day 1

Monday 18 May

Opening Day — Setting the Scene

10:00 – 10:25 25 min

Welcome & Workshop Overview

Lorentz Centre introduction (15 min) + workshop goals (Aditya Parthasarathy & Hao Ding, 10 min)
10:25 – 11:00 35 min

Social Introductory Science Sparklers — Session A

~30 participants: short ~1-minute introductions — who you are, expertise, what you want from the workshop
11:00 – 12:00 60 min

Keynote 1 PTA / GW Science

The first inroads into the low-frequency gravitational-wave spectrum: Results and Challenges
Michael Keith (40 min talk + 20 min Q&A)
12:00 – 13:30 90 min

Lunch
13:30 – 14:30 60 min

Keynote 2 ISM Propagation

The interstellar medium in space and time: current state-of-the-art in scintillometry and imaging techniques
Stella Ocker (40 min + 20 min Q&A)
14:30 – 15:00 30 min

Coffee break
15:00 – 16:00 60 min

Keynote 3 VLBI Astrometry

Precision astrometry on compact objects with VLBI and avenues for advancements
Adam Deller (40 min + 20 min Q&A)
16:00 – 16:30 30 min

Coffee break
16:30 – 17:00 30 min

Social Introductory Science Sparklers — Session B

~25 participants
17:00 onward —

Social Welcome Reception

Day 2

Tuesday 19 May

Tutorials (morning, all tracks) · PTA: Challenges & Solutions (afternoon)

PTA Moderators Rutger van Haasteren, Caterina Tiburzi, Matthew Miles, James Cordes

PTA Trainers Kathrin Grunthal, Aurelien Chalumeau, Sara Manzini

ISM Trainers Nina Gusinskaia, Daniel Baker

VLBI Trainers Shami Chatterjee, Florian Eppel

10:00 – 10:45 45 min

Tutorial VLBI Tutorial Session

Fundamentals and theory of VLBI — led by Shami Chatterjee & Florian Eppel
10:45 – 11:00 15 min

Q&A Questions on VLBI Tutorial
11:00 – 11:45 45 min

Tutorial PTA Tutorial Session

Fundamentals and theory of pulsar timing arrays — led by Kathrin Grunthal, Aurelien Chalumeau & Sara Manzini
11:45 – 12:00 15 min

Q&A Questions on PTA Tutorial
12:00 – 13:30 90 min

Lunch
13:30 – 14:15 45 min

Tutorial ISM Tutorial Session

Fundamentals and theory of the interstellar medium — led by Nina Gusinskaia & Daniel Baker
14:15 – 14:30 15 min

Q&A Questions on ISM Tutorial
14:30 – 15:10 40 min

Keynote 1 PTA Foreground Signals

Pulsar Timing Array Foreground Signals: Origins, Models, and Consequences for Gravitational-Wave Astronomy
Daniel Reardon (30 min + 10 min Q&A)
15:10 – 15:30 20 min

Discussion Discussion Break A

Moderators prioritise topics/questions emerging from Keynote 1
15:30 – 15:45 15 min

Breakout Overview & Team Assignment + Coffee
15:45 – 16:25 40 min

Keynote 2 Continuous Waves with PTAs

Continuous waves from supermassive black hole binaries: facing the challenge of detection and localisation
Niccolò Veronesi (30 min + 10 min Q&A)
16:25 – 16:45 20 min

Discussion Discussion Break B

Moderators finalise shortlist of breakout questions + key ideas
16:45 – 17:00 15 min

Breakout Prep

Teams settle, assign roles, review topic cards
17:00 – 18:00 60 min

Breakout PTA Breakout Sessions

8 teams of 6–7: one PTA challenge + actionable solution

Day 3

Wednesday 20 May

PTA wrap-up (morning) · ISM: Challenges & Solutions

ISM Moderators Dylan Jow, Jacob Turner, Marten van Kerkwijk

ISM Trainers Nina Gusinskaia, Daniel Baker

10:00 – 10:40 40 min

Breakout Outcomes PTA Breakout Pitches

1 reporter per team — tight pitches from Day 2 PTA breakouts
10:40 – 11:30 50 min

Plenary PTA Plenary Discussion

PTA moderators lead guided discussion on the shortlisted topics; define success criteria
11:30 – 12:10 40 min

Keynote 1 Pulsar Scintillometry

Advances in pulsar scintillometry techniques
Robert Main (30 min + 10 min Q&A)
12:10 – 12:30 20 min

Discussion Discussion Break A

Moderators prioritise topics/questions emerging from Keynote 1
12:30 – 14:00 90 min

Lunch
14:00 – 14:40 40 min

Keynote 2 VLBI Astrometry of Scintillation Screens

High-resolution VLBI astrometry of pulsar scintillation screens
Ashley Stock (30 min + 10 min Q&A)
14:40 – 15:00 20 min

Discussion Discussion Break B

Moderators finalise shortlist of breakout questions + key ideas
15:00 – 15:30 30 min

Coffee + Breakout Prep
15:30 – 16:30 60 min

Breakout ISM Breakout Sessions

8 teams of 6–7: one ISM challenge + actionable solution
16:30 – 16:50 20 min

Coffee break + teams finalise 1-page / 1-slide output
16:50 – 17:30 40 min

Breakout Outcomes ISM Breakout Pitches

1 reporter per team — tight pitches
17:30 – 18:00 30 min

Plenary ISM Plenary Discussion

ISM moderators lead guided discussion on the shortlisted topics; define success criteria
Evening —

Social Conference Dinner

Arranged at Galerie Café Leidse Lente.

Day 4

Thursday 21 May

VLBI: Challenges & Solutions

VLBI Moderators John McKean, Robert Wharton, Silke Britzen

VLBI Trainers Jack Radcliffe, Florian Eppel

10:00 – 10:25 25 min

Keynote 1a Heavy Scattering in the Galactic Plane

Heavy Scattering in the Galactic Plane
Andreas Brunthaler (20 min + 5 min Q&A)
10:25 – 10:40 15 min

Keynote 1b First Sub-pc SMBH

Detection of the first sub-pc SMBH and its implications for PTA observations
Silke Britzen (12 min + 3 min Q&A)
10:40 – 11:05 25 min

Discussion Discussion Break A

Facilitated plenary — prioritise topics/questions emerging from Keynote 1
11:05 – 11:45 40 min

Keynote 2 The MSPSRπ2 Project

The MSPSRπ2 project: A large-scale astrometric project for millisecond pulsars
Bailee Wolfe (remote — 30 min + 10 min Q&A)
11:45 – 12:00 15 min

Discussion Discussion Break B

Plenary — finalise shortlist of breakout questions + key ideas
12:00 – 13:30 90 min

Lunch
13:30 – 13:45 15 min

Breakout Overview & Team Assignment

Overview of the breakout sessions and assign roles, and topic cards
13:45 – 15:00 75 min

Breakout VLBI Breakout Sessions

8 teams of 6–7: one VLBI challenge + actionable solution
15:00 – 15:30 30 min

Coffee break + teams finalise 1-page / 1-slide output
15:30 – 16:10 40 min

Breakout Outcomes VLBI Breakout Pitches

1 reporter per team — tight pitches
16:10 – 17:00 50 min

Plenary VLBI Plenary Discussion

All participants: moderators lead guided discussion on the shortlisted topics; define success criteria
17:00 – 17:30 30 min

Working Plan of Action for Friday

Discuss the consolidation goals and structure for Day 5

Day 5

Friday 22 May

Synthesis & Roadmap

10:00 – 12:00 120 min

Working Consolidation Sessions

Collaboratively draft actionable research plans, grant proposals, and observing strategies based on the week's discussions.
12:00 – 13:30 90 min

Lunch
13:30 – 15:00 90 min

Discussion Roadmap & Next Steps

Culminating in a community roadmap document to guide future collaborative efforts across PTA, ISM, and VLBI communities.

Day 5 schedule is preliminary and will be adjusted to accommodate participants who may need to travel.

How Breakout Sessions Work

~55 participants split into 8 teams of 6–7, each tackling one challenge with an actionable solution. Each team has a Chair/Timekeeper, Scribe, Reporter, and Skeptic.

70-minute working method:

Example Breakout Topic Cards

Teams will select from topics like these (final selection made during the workshop):

1. Scattering variability → timing bias

Detect, model, and correct profile/TOA biases from time-variable scattering.

2. Robust DM(t,v) modelling

Define a minimum standard across wideband + multi-telescope data.

3. Screen geometry from scintillometry

Turn arcs/anisotropy into constraints on screen distance, velocities, and timing priors.

4. VLBI + scintillometry fusion

Joint observables/products for robust screen localisation and validation.

5. Solar wind vs ISM disentangling

Operational diagnostics to separate heliosphere from ISM propagation.

6. ISM-informed PTA likelihoods

Inject ISM measurements into PTA analyses as priors and nuisance models.

7. Minimal ISM data product spec

Define a realistic, shareable product that lowers barriers across PTAs.

8. Benchmarks & validation datasets

Shared simulations/real-data benchmarks + metrics to compare correction methods.

This programme is preliminary and will be updated as the workshop approaches. Check back regularly or follow announcements on the main page.