The SFXC workshop

21 Sept 2025, 17:00 → 23 Sept 2025, 19:00 Europe/Amsterdam

The SFXC workshop is aimed at individuals interested in using the Super FX Correlator ("SFXC") for software correlation of data from their own VLBI instruments (or other long-ish baseline radio interferometers), as well as scientists who want to exploit SFXC's advanced features by doing their own correlation.

The workshop will take place over of two days, mixing theory and practical hands-on sessions at JIVE's host institute ASTRON in Dwingeloo, The Netherlands. There will also be room for discussion about future developments of SFXC (including GPU-based correlation) and suggestions for improving the SFXC documentation.

The number of participants is limited to twenty (20) to enable a useful teacher-to-student ratio for the practical sessions. If we receive more than 20 registrations by the registration deadline of May 25th 2025, we will select participants based on the survey in the registration form. Selected participants will receive confirmation before June 6th 2025. Please hold off making travel arrangements until your participation has been confirmed!

Lectures will be delivered by the SFXC developers, JIVE's in-house experts, and external users already using SFXC for their own data processing. Topics will include: correlator models; correlation preparation; mixed-bandwidth correlation; geodetic correlation; real-time correlation; post-processing of correlator output; using SFXC for space science; and using SFXC for FRB localization.

We expect each participant to bring a laptop with an ssh client installed, to have some experience with radio interferometry, and to be familliar with a UNIX/Linux shell command-line environment and  programming in Python.

The workshop is offered free of charge, but no travel, lodging, sustenance, or other form of financial support will be available. A block booking of hotel rooms at the nearby Hotel de Borken has been made and bicycles will be provided to commute between the hotel and ASTRON's premises.

An ice-breaker event will be organised on Sunday 21 September, and we'll have a conference dinner on one of the nights of the workshop. Lunch/coffee break refreshments will also be provided.

JIVE and ASTRON are dedicated to provide an inclusive and safe environment for everyone: employees and visitors; therefore this workshop is covered by the Dwingeloo code of conduct.

For questions please contact us at sfxc-workshop AT jive DOT eu

Local Organizing Committee (LOC)	Scientific Organizing Committee (SOC)
Mark Kettenis JIVE	Franz Kirsten Chalmers University of Technology
Aard Keimpema JIVE	Jack Radcliffe University of Manchester
Des Small JIVE	Mark Kettenis JIVE
Yvonne Kool JIVE	Aard Keimpema JIVE
Marjolein Verkouter JIVE

Sunday 21 September

1 Ice-breaker reception

Either at ASTRON or at De Börken?

Monday 22 September

Theory 1

2 (VLBI) Correlation 101

Introduction to correlation and correlator basics, history

Speaker: Bob Campbell (JIVE)

3 Correlation preparation

Knowing what (meta)data is needed for correlation, where to get it and how to store/format it.

Speakers: Aard Keimpema (JIVE), Mark Kettenis (JIVE)

10:30 coffee

Hybrid session 1

Theory 2

4 Setting up the correlator

After an introduction to setting up a cluster for running the SFXC distributed correlator, participants will be setting up and verify the operation of their correlation environment.

Speakers: Aard Keimpema (JIVE), Mark Kettenis (JIVE)

12:30 lunch

5 Hands-on 1: Getting everyone's correlator to run

On a simple VLBI observation

Speakers: Aard Keimpema (JIVE), Mark Kettenis (JIVE)

15:00 Tea

6 Hands-on 2: Post-correlation processing

Translating the SFXC output into more standard data format(s) for inspection and export/archiving

Speaker: Mrs Marjolein Verkouter (Joint Institute for VLBI - ERIC)

Q+A

7 Workshop dinner

Tuesday 23 September

Hybrid 3: Pulsar processing

8 Pulsar processing

Introduction

Speakers: Aard Keimpema (JIVE), Franz Kirsten (Onsala)

9 Pulsar gating

Handling a FITS file with pulses in

Speaker: Franz Kirsten (Onsala)

10 Producing filterbank format output + run PSR tools

Speaker: Franz Kirsten (Onsala)

10:30 coffee

Hybrid 4: FRB Processing

11 PRECISE processing

How the PRECISE EVN-lite mode actually works and what it does

Speaker: Franz Kirsten (Onsala)

12 Semi-automated pulse processing

How to use and run the semi-automatic gating system

Speaker: Aard Keimpema (JIVE)

13 SFXC and duct-tape = single dish FRB workflow

How several components can be duct-taped together to form a workflow for unique science

Speaker: Omar Ould-Boukattine (UvA, ASTRON)

12:30 lunch

14 Hybrid 5: Wide-field processing

Bright source, two images, check fringes
Same dataset as Day 1

Speaker: Jack Radcliffe (University of Manchester)

15:00 Tea

15 Hybrid 6: Geodesy

Same dataset as Day 1; check Geo data on flexbuffs @ JIVE
Running "sfxc2mark4", "pulse cal" (aka phase cal tone processing)
Running "fourfit"

Speaker: Mark Kettenis (JIVE)

Future bells & whistles

16 SFXC - the GPU version

Showcasing recent results from porting SFXC to GPU accelated platform(s)

Speaker: Aard Keimpema (JIVE)

17 SKA-VLBI

SKA-VLBI:
- intro (Jack R)
- requires multi-beam processing; planning to implement as multiple
field center correlation w/ extra bookkeeping (Mark K)

Speakers: Jack Radcliffe (University of Manchester), Mark Kettenis (JIVE)

18 User / community input discussion

• knee-jerk feedback from participants/unfiltered comments!
• needs/wishes from the community