WE-Heraeus Lorentz Workshop

Advancing Pulsar Science in the Era of Modern Interferometers

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

View Programme Lorentz Center Page

Workshop Highlights

Five Days · Three Communities · One Conversation

Keynotes, tutorials, breakouts & the conference dinner — a glimpse of the week.

Scientific Context

Bridging Gravitational Waves, the ISM & VLBI

The recent milestone detection of the nanohertz gravitational wave background by Pulsar Timing Arrays has opened an entirely new observational window into the Universe. As we move towards the most sensitive datasets ever assembled, the astrophysical interpretation of these signals is limited by two key challenges: poor models of the intervening interstellar medium (ISM), and uncertainties in pulsar distance measurements.

This workshop brings together, for the first time, leading experts in gravitational wave science, interstellar medium studies, and Very Long Baseline Interferometry (VLBI) to collaboratively identify and address these limitations. Through keynote talks, interactive tutorials, and structured breakout sessions, we aim to produce actionable research plans and observing strategies that integrate cutting-edge techniques across all three fields.

The workshop is particularly timely given significant upgrades to the European VLBI Network, the advent of next-generation radio facilities like the SKA and DSA-2000, and the forthcoming third data release of the International Pulsar Timing Array.

Advancing Pulsar Science in the Era of Modern Interferometers — workshop poster

Programme

Five Days of Science

Keynotes, interactive tutorials, and structured breakout sessions designed to produce concrete, actionable outcomes.

Opening Day — Setting the Scene

10:00 – 10:25

Welcome & Workshop Overview

Lorentz Centre introduction + workshop goals (Aditya Parthasarathy & Hao Ding)

10:25 – 11:00

SocialIntroductory Science Sparklers — Session A

~30 participants: 1-minute introductions sharing expertise, interests, and goals for the week

11:00 – 12:00

KeynotePTA / GW Science

The first inroads into the low-frequency gravitational-wave spectrum: Results and Challenges — Michael Keith

12:00 – 13:30

Lunch

13:30 – 14:30

KeynoteISM Propagation

The interstellar medium in space and time: current state-of-the-art in scintillometry and imaging techniques — Stella Ocker

14:30 – 15:00

Coffee Break

15:00 – 16:00

KeynoteVLBI Astrometry

Precision astrometry on compact objects with VLBI and avenues for advancements — Adam Deller

16:00 – 16:30

Coffee Break

16:30 – 17:00

SocialIntroductory Science Sparklers — Session B

~25 participants

17:00 onward

SocialWelcome Reception

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

TutorialVLBI Tutorial Session

Fundamentals and theory — led by Shami Chatterjee & Florian Eppel

10:45 – 11:00

Q&AQuestions on VLBI Tutorial

11:00 – 11:45

TutorialPTA Tutorial Session

Fundamentals and theory — led by Kathrin Grunthal, Aurelien Chalumeau & Sara Manzini

11:45 – 12:00

Q&AQuestions on PTA Tutorial

12:00 – 13:30

Lunch

13:30 – 14:15

TutorialISM Tutorial Session

Fundamentals and theory — led by Nina Gusinskaia & Daniel Baker

14:15 – 14:30

Q&AQuestions on ISM Tutorial

14:30 – 15:10

Keynote 1PTA Foreground Signals

Pulsar Timing Array Foreground Signals: Origins, Models, and Consequences for Gravitational-Wave Astronomy — Daniel Reardon

15:10 – 15:30

DiscussionDiscussion Break A

Moderators prioritise topics emerging from Keynote 1

15:30 – 15:45

Breakout Overview & Team Assignment + Coffee

15:45 – 16:25

Keynote 2Continuous Waves with PTAs

Continuous waves from supermassive black hole binaries: facing the challenge of detection and localisation — Niccolò Veronesi

16:25 – 16:45

DiscussionDiscussion Break B

Moderators finalise shortlist of breakout questions + key ideas

16:45 – 17:00

Breakout Prep

17:00 – 18:00

BreakoutPTA Breakout Sessions

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

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

ISM Moderators Dylan Jow, Jacob Turner, Marten van Kerkwijk

10:00 – 10:40

PitchesPTA Breakout Outcomes

1 reporter per team — tight pitches from Day 2 PTA breakouts

10:40 – 11:30

PlenaryPTA Plenary Discussion

PTA moderators lead guided discussion; define success criteria

11:30 – 12:10

Keynote 1Pulsar Scintillometry

Advances in pulsar scintillometry techniques — Robert Main

12:10 – 12:30

DiscussionDiscussion Break A

Moderators prioritise topics emerging from Keynote 1

12:30 – 14:00

Lunch

14:00 – 14:40

Keynote 2VLBI Astrometry of Scintillation Screens

High-resolution VLBI astrometry of pulsar scintillation screens — Ashley Stock

14:40 – 15:00

DiscussionDiscussion Break B

Moderators finalise breakout questions + key ideas

15:00 – 15:30

Coffee + Breakout Prep

15:30 – 16:30

BreakoutISM Breakout Sessions

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

16:30 – 16:50

Coffee break + teams finalise output

16:50 – 17:30

PitchesISM Breakout Outcomes

1 reporter per team — tight pitches

17:30 – 18:00

PlenaryISM Plenary Discussion

ISM moderators lead guided discussion; define success criteria

Evening

SocialConference Dinner

Arranged at Galerie Café Leidse Lente.

VLBI: Challenges & Solutions

VLBI Moderators John McKean, Robert Wharton, Silke Britzen

10:00 – 10:25

Keynote 1aHeavy Scattering in the Galactic Plane

Heavy Scattering in the Galactic Plane — Andreas Brunthaler

10:25 – 10:40

Keynote 1bFirst Sub-pc SMBH

Detection of the first sub-pc SMBH and its implications for PTA observations — Silke Britzen

10:40 – 11:05

DiscussionDiscussion Break A

Facilitated plenary — prioritise topics emerging from Keynote 1

11:05 – 11:45

Keynote 2The MSPSRπ2 Project

The MSPSRπ2 project: A large-scale astrometric project for millisecond pulsars — Bailee Wolfe (remote)

11:45 – 12:00

DiscussionDiscussion Break B

Plenary finalises shortlist of breakout questions + key ideas

12:00 – 13:30

Lunch

13:30 – 13:45

Breakout Overview & Team Assignment

13:45 – 15:00

BreakoutVLBI Breakout Sessions

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

15:00 – 15:30

Coffee break + teams finalise output

15:30 – 16:10

PitchesVLBI Breakout Outcomes

1 reporter per team — tight pitches

16:10 – 17:00

PlenaryVLBI Plenary Discussion

Moderators lead guided discussion on shortlisted topics; define success criteria

17:00 – 17:30

WorkingPlan of Action for Friday

Discuss the consolidation goals and structure for Day 5

Synthesis & Roadmap

10:00 – 12:00

WorkingConsolidation Sessions

Participants collaboratively draft actionable research plans, grant proposals, and observing strategies based on the week's discussions.

12:00 – 13:30

Lunch

13:30 – 15:00

DiscussionRoadmap & Next Steps

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

The programme is preliminary and subject to change. A detailed schedule with breakout topic cards will be shared closer to the workshop. See the full detailed programme →

Participants

Researchers from Around the World

Experts spanning pulsar timing, ISM studies, VLBI astrometry, and instrumentation.

Scientific Organising Committee

Organisers

Aditya Parthasarathy

Chair · ASTRON & University of Amsterdam

Expert in precision pulsar timing and gravitational wave science. Led key efforts in the European and International PTA collaborations. ERC Starting Grant and NWO-I Veni fellow.

Nataliya Porayko

Sternberg Astronomical Institute & MPIfR

Specialist in gravitational wave science and dark matter searches with PTAs. Executive committee member of the EPTA, steering committee of the IPTA.

Pikky Atri

ASTRON

Expert in VLBI astrometry and compact object studies. WISE fellow leading observing campaigns with major VLBI facilities worldwide.

Tim Sprenger

MPIfR, Germany

Specialist in pulsar scintillation and novel data analysis methods. Developing theoretical models for anisotropic interstellar scattering screens.

Hao Ding

National Astronomical Observatories of China

Precision radio astrometry using VLBI. Led the largest astrometric survey of millisecond pulsars. IAU PhD Prize honourable mention.

Workshop Coordinator: Emmy Verlek-Hage, Lorentz Center · verlek@lorentzcenter.nl · +31 71 527 5659

Practical Information

Logistics

Everything you need to know about attending the workshop in Leiden.

📍 Venue

Lorentz Center@Omega
Niels Bohrweg 1, Leiden (Bio Science Park)
2nd floor of the Snellius building

For navigation systems, please use destination: Niels Bohrweg 4, or plan your route via 9292.nl.

✈️ Getting There

By train: A direct train leaves from Schiphol Airport to Leiden Central Station every 15 minutes. From Leiden station:

  • Walk: approx. 25-minute walk from Central Station to the Lorentz Center
  • Taxi: about 10 minutes, costs approx. €15
  • Bus: nearest stops are Bio Science Park-Oost / Plesmanlaan, Wassenaarseweg/Corpus, or Niels Bohrweg

Plan your journey at 9292.nl

By car: Please email the organisers by 11 May to register for parking lot access.

🏨 Accommodation

If you have requested a hotel, an updated hotel confirmation will be mailed to you. Please check this carefully and notify the workshop coordinator of any changes. Do not contact the hotel directly — the workshop coordinator is the contact person for the hotel.

🍲 Meals & Social

Lunch vouchers: At the start of the workshop you will receive lunch vouchers for the week, usable in the restaurant on the first floor of the Snellius building.

Welcome reception: On Monday afternoon we will host a welcome reception at the Lorentz Center.

Workshop dinner: A dinner has been arranged for Wednesday evening at Galerie Café Leidse Lente. A sign-up list will circulate at the start of the workshop where you can confirm attendance and dietary requirements.

💻 Presentations & Internet

Bring your own device: You need your own laptop to present in the lecture room.

ClickShare: Share your presentation wirelessly. Please download the ClickShare app before the workshop. USB and HDMI connections are also available.

Internet: Wireless internet via eduroam is available throughout the Lorentz Center. You will receive an automated email from Leiden University with temporary login credentials.

🚲 Bikes

Bicycle rental is available at the Lorentz Center for €5 per person per day (cash only, limited availability). Ask upon arrival. ATMs are available at the airport and near the train station.

📹 Zoom (Remote Participants)

This workshop is partially open to specific online participants. Please download the Zoom app (laptop/PC recommended over tablet or phone). The Zoom link will be shared via email.

♥️ Facilities & Code of Conduct

The Lorentz Center is accessible to people with disabilities. A quiet/prayer room and a nursing room are available — please don't hesitate to ask.

Please review the Lorentz Center Code of Conduct ahead of the workshop.

Updates

Announcements

May 2026

Programme v.2 posted

The programme has been updated: all three tutorials (VLBI, PTA, ISM) are now consolidated on Tuesday morning; the Day-2 afternoon focuses on PTA keynotes and breakouts; Day 3 includes the PTA wrap-up plenary alongside the ISM session. Moderator and trainer assignments for each track are now listed. See the detailed programme.

March 2026

Detailed programme & breakout topic cards

The full programme with breakout topic assignments, interactive session details, and topic cards has been posted. See the detailed programme.

March 2026

Workshop website launched

The workshop website is now live. Programme details and logistics information will be updated as we approach May.