Konstantin Sukharnikov Scientific instrumentation

A hobby. An independent overview compiled from public sources by a science and space enthusiast. I am not involved in these missions or facilities; my own work is detector electronics at European XFEL. My projects →

Facility · Synchrotrons

PETRA III / PETRA IV

6 GeV storage ring, 2.3 km (PETRA III), to be rebuilt as the fourth-generation source PETRA IV in the same tunnel

Status
Operating
Location
Hamburg, Germany
Operator
DESY
Next
2026–2027 BMFTR decision on funding PETRA IV (expected)

Summary

PETRA III: 6 GeV, 100 mA, a circumference of 2,304 m, horizontal emittance 1.2–1.3 nm·rad (two DESY pages give different values), 25 user beamlines (PETRA III, parameters). PETRA IV would rebuild the ring in the existing tunnel as a fourth-generation source: the beam would be focused 100 to 1,000 times better, with 36 beamlines in four halls (PETRA IV). The cost is about €1.8 billion (2025 prices) over nine years. Together with European XFEL and FLASH, it makes Hamburg the largest centre of X-ray sources; for detector developers, PETRA IV would be another major customer.

Now as of 9 Nov 2026

There is no funding decision yet. On 27 March 2026 the German Science Council (Wissenschaftsrat) rated PETRA IV as scientifically highly relevant, internationally outstanding and strategically important; the final decision lies with the federal research ministry (BMFTR). DESY estimates that with a quick positive decision the project could start as early as 2027, with X-rays for experiments around 2032 (DESY Photon Science, 27 March 2026). DESY had said it was important to have a decision by mid-2026 at the latest (DESY News, 2025); as of November 2026, no decision has been reported. Under the current plan, construction of the experimental hall in Lise-Meitner-Park would start in 2028 and take about two years; it cannot start before the project is approved (PETRA IV — construction).

No date has been announced for shutting down PETRA III. Documents from 2022–2023 mentioned the end of 2026 or January 2027; those dates are out of date.

Key dates

  1. Nov 2019PETRA IV conceptual design reportdone
  2. 17 Nov 2023Bundestag budget committee: €40 million for preparationdone
  3. Jul 2025BMFTR puts PETRA IV on its shortlist of large infrastructuresdone
  4. 27 Mar 2026Positive assessment by the Wissenschaftsratdone
  5. 2026–2027BMFTR funding decisionexpected
  6. 2027Project start (if decided quickly)conditional
  7. 2028Construction of the experimental hall beginsplanned
  8. ≈ 2032PETRA IV X-rays for experimentsplanned

Milestones: PETRA IV milestones.

Timeline

  1. 27 Mar 2026Wissenschaftsrat recommends PETRA IV — DESY, WR, Drs. 3152-26
  2. Jul 2025On the BMFTR shortlist — PETRA IV milestones