Low Energy Ion Ring (LEIR)

LEIR is meant to stack several (typically 7) $^{208}Pb^{54+}$ (about 206.5 times greater mass than the proton) injections at 4.2 MeV/u to 72 MeV/u.

References

SY-BI EDMS repository EDMS
2020 D.Gamba et al, Discussion on LEIR cooler diagnostics, indico
2018 G.Tranquille, 40 Years of Electron Cooling at CERN, IPAC2018 MOZGBF3
- It contains several references
2018 O. Marqversen, LEIR Schottky measurements and a proposal for using a distributed BPM system for Schottky measurements in ELENA, indico
2016 LHC Injectors Upgrade - Vol 2 - Ions CERN-ACC-2016-0041
2008 G.Tranquille et al., ELECTRON COOLING EXPERIMENTS AT LEIR, 2008, LHC-PROJECT-REPORT-1111
- Extensive overview of measurements of cooling performance with different settings of the e-cooler
2007 G.Tranquille, Cooling Results from LEIR, COOL2007 TUM1I01
- Several results, most of which also presented in 2008 review by Gerard (LHC-PROJECT-REPORT-1111)
2006 G.Tranquille et al., LEIR ELECTRON COOLER STATUS, 2006, lhc-project-report-944
First report on e- beam current as a function o grid and control
- Some details about magnetic field correction
2006 G.Tranquille et al., COMMISSIONING OF THE LEIR ELECTRON COOLER WITH Pb+54 IONS, rupac2006, webo01
- Several details about commissioning (e.g. issue with vacuum?!), with some references.
- It states that pancake solenoids allow to achieve better than $B_\perp/B < 10^{-4}$ .
2008 G.Tranquille et al., COOLED BEAM DIAGNOSTICS ON LEIR, EPAC08, TUPC102
2006 Valentin Bocharov et al., First Tests of LEIR — Cooler at BINP, 2006, COOL2006
- Several details, not found elsewhere
2004 G.Tranquille, Specification of a new electron cooler for the low energy ion accumulator ring, LEIR NIMA.2004.06.072
2002 Feasibility study for the design, construction and testing of an electron cooler for LEIR (CERN), EDMS #2323592
- Details of implementation of LEIR e-cooler, including derivation of forces/effects/cooling times...
2002 THE ELECTRON GUN WITH VARIABLE BEAM PROFILE FOR OPTIMIZATION OF ELECTRON COOLING, EPAC2002, WEPRI049
- Some details about e- gun designed for CSR with ULTRASAM/measurement of beam profile. Same gun should be in LEIR
1997 S.A.Baird et al., Recent Results on Lead-Ion Accumulation in LEAR for the LHC. CERN-PS-97-003-DI
- Details about lifetime measurement using Pb52+ Pb53+ Pb54+ Pb55+ as well as e-cooler e- beam neutralisation
1996 J. Bosser, Review of recente work on electron cooling at LEAR CERN-PS-97-037-HP
- Details about lifetime measurement using Pb52+ Pb53+ Pb54+ Pb55+ as well as e-cooler e- beam neutralisation
1993 P. Lefevre, and D. Mohl, A low energy accumulation ring of ions for LHC (a feasibility study), CERN-LHC-Note-259
- Contains several details about the machine, but also formulas and estimates for cooling times etc...

LEIR E-COOLER

The LEIR cooler e- gun is immersed in a high magnetic field (up to about 2.3 kGs or 0.23 T), while the drift is at about 750 Gs (0.075 T), giving the possibility to arrive to expansion factor of about 3, which corresponds to $\sqrt{3}$ max increase in with respect to the cathode radius of about 14 mm, i.e. up to about 24 mm of e-beam radius for k=3.

Gun settings

See G. Tranquille notes:

Powering scheme

Detailed electrical schematics available here (by A. Frassier)

E-cooler parameters

Parameter	Value
`(Main) Ion particle`	$^{208}Pb^{54+}$
`Momentum`	~88 MeV/c/u
`Electron energy`	2.3 keV (<6.5keV)
`Relativistic beta`	0.094
`Electron current`	600 mA
`Cooler length`	2.5 m
`Ring length`	78.54 m (about $25\pi$ )
`Gun magnet field`	Up to 2.3 kG
`Drift magnet field`	750 G
`Electron beam radius`	14-25 mm