14th Collaboration Workshop on Longitudinal Diagnostics

29 Sept 2025, 08:30 → 1 Oct 2025, 14:30 Europe/Berlin

Building 3, Meeting Room BAH1 (DESY Campus, Hamburg)

This workshop series focuses on joint developments of longitudinal diagnostics for ultra-short electron bunches and THz pulses in current and future accelerators.

The program contains overview talks with updates on different machines and systems, tutorial-style talks on specific topics and most of the time will be organized in working groups. 

As a registered participant you are encouraged to actively contribute to the working group(s) with the aim of exchanging ideas and planning of collaborations or joint measurements.

Morevoer, you have the opportunity to present a poster, including a 3 min speed talk.

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Part of this event was kindly sponsored by the European XFEL GmbH. 

CWLD Mailing-list Info

DESY-Campus-eng-hh.pdf

Poster_CWLD14.pdf

XFEL-Campus-map.pdf

Monday 29 September

08:30 → 09:00 Registration with Coffee & Snacks

09:00 → 10:20 Welcome & Introduction

facility / project overview talks

09:00 Welcome & Organizational Topics

Speakers: Bernd Steffen (MSK (Strahlkontrollen)), Marie Kristin Czwalinna (DESY, MSK)

09:15 Recent Upgrades and News from Accelerators at DESY

Speaker: Marie Kristin Czwalinna (DESY, MSK)

09:35 Safety Instruction for Visitors

All guests entering the European XFEL facility (accelerator or photon tunnel) must be informed of general safety measures.
For access to the round tunnel sections deep underground, a so-called oxy-box must be carried at all times; a special training is mandatory.
(The oxy-box is a safety device that provides oxygen in the unlikely event of a smoke or fire emergency, ensuring safe passage to the nearest emergency exit from the tunnel.)

Every DESY employee who has access to XFEL tunnels, you won't have to attend this safety instruction.
However, please remember to bring your DACHS card, your personal dosimeter & (if possible) a transponder.

safety-instr-intro.pdf

10:20 → 11:20 Brunch Break

11:30 → 12:30 Connection: Transition to EuXFEL Schenefeld Campus

HVV group tickets will be handed out at the workshop.
you do not need to buy your own single-trip tickets.

connectionHVV-option-1.pdf

connectionHVV-option-2.pdf

connectionHVV-option-3.pdf

connectionHVV-option-4.pdf

12:45 → 12:55 Welcome at European XFEL

Speaker: Jan Gruenert (Eur.XFEL (European XFEL))

2025-09-29 EuXFEL Welcome for Workshop.pptx

13:05 → 13:45 Visit Experimental Hall

13:45 → 14:00 Refreshments

Tea, Water, juice

14:00 → 16:00 Presentations (Mon Sep 29)

14:00 Development and Challenges for Room-Temperature Operable THz Detection Systems

Over the past few decades, significant progress has been made in the Terahertz (THz) domain, closing the gap between the electronics and optics regions of the electromagnetic spectrum. Especially the development of sources and detectors is of great importance for enhancing the capabilities to explore the THz spectrum to its fullest extent. THz radiation sources based on accelerators offer new avenues for studying physical matter and its applications. To fully explore the potential of this spectrum, THz detection systems, such as THz detectors, are necessary. In this overview talk, we present recent developments and challenges encountered as we advance the technology to a mature level. The summarized room-temperature operable THz detectors are presented, along with other competent technologies. The key factors for improving THz detector performance, along with the selected necessary THz electronics, are discussed. The idea is to bring developers and users of THz technology to a common platform to discuss needs and pave the way for a future roadmap that enriches the THz domain for all.

Speaker: Rahul Yadav (Terahertz Devices and Systems, IMP , TU Darmstadt)

14:30 Facility report - HZDR

tbc

Speaker: Michael Kuntzsch (HZDR)

Kuntzsch_HZDR.pdf

14:50 Facility development highlight - STERN

The EuXFEL R&D project, STERN, is exploring beam-based radiation generation methods using Cherenkov waveguides and diffraction radiation to satisfy these user requirements.

Speaker: Francois Lemery (MXL (XFEL))

STERN_CWLD14.pptx

15:10 Science highlight - An X-ray - optical pulse arrival monitor based on THz emission

Speaker: Robert Carley (Eur.XFEL (European XFEL))

THz-timing-tool-2025-09-29_v3.pptx

15:40 Photon Diagnostics at European XFEL

A brief overview of photon diagnostic stations which you will be shown during the tour.

Speaker: Jan Gruenert (Eur.XFEL (European XFEL))

2025-09-29 Longitudinal Diagnostics Workshop - Photon Diagnostics - Grünert.pptx

16:00 → 17:00 Reception & Snacks

17:15 → 18:00 Walk-through tour Photon Tunnel

sightseeing tour with a stop at the photon beam diagnostics and an experimental station.

18:00 → 18:30 Transition from Schenefeld to DESY Campus

(for everyone who does not participate in the long walk through XTL)

18:00 → 19:15 Walk through XFEL (from Schenefeld Campus back to DESY Campus)

9 min - check into gate
45 min - walk ( 3 km) + sightseeing
6 min - back to EG and check out through gate

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sum = 01:00h

(a bit faster if by bike)

18:30 → 19:15 Tour XFEL Injector

8 min - check into gate and go to UG7
20 min - tour through injector
10 min - look into XTL
6 min - back to EG and check out through gate

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sum = 00:40h

Tuesday 30 September

08:30 → 09:00 Breakfast Snack / Coffee

09:00 → 09:40 Facility Reports

09:00 Highlights of MAX IV

Speaker: Oliver Grimm (Lund University, MAX IV Laboratory)

09:20 News from KIT (Flute, C-Start)

Speaker: Gudrun Niehues (KIT)

09:40 → 10:00 Focus Topic - A Compact Transverse Deflecting system based on THz streaking

Split ring resonator

Speaker: Michael Nasse (Karlsruhe Institute of Technology)

10:00 → 10:15 Coffee Refill

10:15 → 11:00 Speed Talks - Poster Presentation

each Poster presentation will be accompanied by a short advertisement of up to 3min length.

WS2025_Speedtalks.pdf

11:00 → 12:00 Poster Presentations

Time to visit the posters and discuss specific topics with the experts.
Posters will be accessible throughout the whole event, in the hallway of Bldg.3, ground floor.

Please view the list of contributions in this session for details on the presented topics.

12:00 → 13:00 Working Lunch Break & Poster Session continued

13:00 → 14:20 Parallel working groups: Part 1

working groups

13:00 Working Group - Arrivaltime / sub-pC detection

13:00 Working Group - Spectral Domain

13:00 Working Group - Time Domain / EO

14:20 → 14:40 Coffee Break

14:40 → 16:00 Parallel working groups: Part 2 https://desy.zoom.us/j/97740113556?pwd=aEY4cnJWOFN3QjlwU0VEZlFzVnZjUT09

talks / special topics

14:40 Working Group - LPS reconstruction

14:40 Working Group - New THz power detectors / redesign Pyro-box

14:40 Working Group - space for spontaneously appearing hot topics

Scanned Document 30.09.2025 at 15.50.35.pdf

16:00 → 16:45 Refreshments & Snacks - served 16:00 to 18:30

time buffer before "Guest Talk" and afterwards to bridge the time before going to Hamburg Harbour

16:45 → 17:45 Guest Talk - AI Technology Transfer: Unlocking the Potential of Small and Medium-Sized Enterprises

Artificial Intelligence (AI) is emerging as a key enabling technology that is transforming a wide range of business sectors . It allows companies to increase efficiency, gain deeper insights from their data, and explore entirely new business opportunities. Companies that fail to engage with AI now risk falling behind in competitiveness and innovation capacity.
This talk presents practical insights from the KI.SH project, in which universities collaborate with small and medium-sized enterprises (SMEs) to support the introduction and application of AI solutions. Selected case examples will illustrate how technology transfer from academia to industry can create real-world value in the context of SMEs. Beyond practical results, the talk also shares lessons learned from this process that may be valuable for future scientific and academic work.

Speaker: Nils Lockmann

18:45 → 19:30 Transfer to Hamburg Harbour

Transfer with public transport (HVV).
If we all go together, we can offer group tickets (1x for groups of 5 persons)

If you prefer to organize you own trip: you get single and day tickets in the Online Shop https://www.hvv.de/en/tickets/onlineshop or via the hvv Apps https://www.hvv.de/en/service/hvv-apps with a discount of 7%.

Tickets can only be bought in the bus, with an HVV pre-paid card. (better option is the Online or App ticket).

Fare zone = "Hamburg AB"

going from DESY to Hamburg Harbour:

Take the bus line 1 from "Zum Hünengrab (DESY)" in direction of Bf. Altona.
and then

1. either change after 2 stops at "Trabrennbahn, Bahrenfeld" to bus line 2 in direction of U S Berliner Tor,
2. or change after 5 stops at "S Othmarschen" from bus line 1 to "S Bahn" line S1 in direction of Ohlsdorf.

Get off the bus or S Bahn train at "Landungsbrücken".

The trip takes about 30min (with either option).

From there, it is a short stroll along the harbour to the location of the restaurant.

Maps_path_SLandungsbrücken_Restaurant-Fischerhaus.jpg

19:30 → 22:00 Social Get-together

After a short stroll along the Elbe river-side we will convene at 20:00 for dinner at the Fischerhaus restaurant.
(each person will pay their own bill)

Fischerhaus_Menu_de.pdf

Fischerhaus_Menu_eng.pdf

Wednesday 1 October

08:30 → 08:45 Breakfast Snacks & Coffee

08:45 → 09:30 Preparation time for the WG summaries

Coffee and Snacks are served from 08:30 onwards.
Meeting room is also opened by then, in case you need the time to prepare or finish the working group summaries.

09:30 → 10:10 Beam diagnostics at rings

09:30 Diagnostics for ring injection

Speaker: Erik Mansten (MAX IV Laboratory, Lund University)

09:50 Longitudinal diagnostics R&D at KARA for short bunches in storage rings

Speaker: Micha Reißig (Karlsruher Institut für Technologie (KIT))

10:15 → 11:05 Working group summaries

Working Group Conveners: Please upload your summary as document, slides or simple notes text file to the according sub-contribution in Indico.

2025-09-30_WG-Detectors_Introduction.pdf

Bunch Length Measurement in SLS 2.pptx

SummaryLPS.pdf

Summary_WG_subpCbunches.pdf

Summary_Workgroup_Detectors.pdf

Working Group_SpectralDomain.pptx

11:15 → 12:00 Brunch Break

12:00 → 12:45 Workshop Results: Exchange on new collaboration topics and upcoming joint measurement campaigns.

Exchange on new collaboration topics and joint measurement campaigns.

cwld14_wrapup.pdf

12:45 → 13:00 Summary & Close-out