A 25 GeV Electron facility for Europe.
Report on the ELFE @ HERA project.
The Concept Design Report (CDR) has been completed.
A PDF version (411 kB)
of this report is available at the NIKHEF site.
A short description of the ELFE proposal is available.
A full report has been published in october 1992:
The ELFE REPORT
An Electron Facility for Europe, edited by J. Arvieux
and E. De Sanctis
After termination of the present physics program with HERA at
DESY, Hamburg, possible use of the ring as a stretcher ring for
ELFE could be considered. In February 1996 an international study
group has been formed by Bernard Frois (Saclay) to study the modification
of the HERA electron ring into a 25 GeV stretcher ring for electrons.
Details of the study group:
The goal of the study group was :
- Investigate the possibility to use TESLA as an injector for
ELFE, an ELectron Facility For Europe.
- Convert the HERA electron ring into a 25 GeV electron stretcher
- Evaluate the performances of the extracted beam in terms of
emittance, energy spread and duty factor.
The main efforts
- Modification of the HERA e-ring lattice for the needs of slow
- Beam extraction : Analysis of possible extraction methods,
simulation of the extraction process, definition of the extraction
- Beam injection: optics and hardware.
- A new RF system in HERA and multibunch instabilities.
- Time structure of the injected beam.
- Compensation of beam loading in the injection linac.
Solutions have been found for these problems, although the
control of beam instabilities will probably not be easy. The achievable
performances of the extracted beam have been calculated assuming
that the effects of machine imperfections could be corrected.
The performance that can be expected:
||15 - 25 |
||1.2 (15 GeV) - 2.2 ( 25 GeV)|
|Macroscopic duty factor ||percent
||2.3 (433 MHz)|
|Min. horizontal emittance ||mm * microrad
||4 (15 GeV) - 12 (25 GeV)|
Therefore, we conclude that HERA can be used in association
with TESLA to produce a high duty factor electron beam for fixed
nuclear target experiments.
ELFE@DESY appears to be feasible
The study group has terminated its activities.
The next activities will be:
- Cost estimate (by Saclay and DESY).
- Publicizing the results of the study.
- Defending the results in scientific meetings.
Updated on *
We welcome your remarks and suggestions.