Operative Unit

Insertion Devices

A range of insertion devices has been designed, built and installed in the storage ring starting from 1992. Most of them employ the permanent magnet technology. The only exception is one electromagnetic variably polarised wiggler/undulator.

The main parameters of the ELETTRA insertion devices are listed in the following table:

ID	type	straight section	Period (mm)	No. periods	Bo (T)	Deflection parameters	gap (mm)
EU10.0	PM/Elliptical	1	100.36	20+20	1.021 0.626 0.775	Ky=9.6 Kh=5.9 Kx=7.3	19
U5.6	PM/Linear	2	56.36	3 x 27	0.693	Ky=3.6	19
U12.5	PM/Linear	3	125.16	3 x 12	0.506	Ky=5.9	32
EEW	EM/Elliptical	4	212.0	16	0.50.1	Ky=10.0 Kx= 2.0	18
W14.0	HYB/Linear	5	140.0	3 x 9.5	1.501	Ky=19.6	22
U12.5	PM/Linear	6	125.16	3 x 12	0.560	Ky=6.55	30
U8.0	PM/Linear	7	80.36	19	0.710	Ky=5.6	26
EU4.8	PM/Elliptical	8	48.36	44	0.584 0.296 0.343	Ky=2.6 Kh=1.3 Kx=1.6	19
EU7.7	PM/Elliptical	8	77.16	28	0.915 0.528 0.636	Ky=6.6 Kh=3.8 Kx=4.6	19
EU6.0	PM/Elliptical	9	60.36	36	0.781 0.419 0.510	Ky=4.4 Kh=2.4 Kx=2.9	19
EU12.5	PM/Elliptical	9	125.00	17	0.771 0.465 0.595	Ky=9.0 Kh=5.4 Kx=6.9	18.6
FEU	PM/Figure-8	10	140.00	16+16	0.9 (v) 0.1 (h)	Kx=3.4 Ky=9.4	19
SCW	SC/Linear	11	60.00	24.5	3.5	Ky=19.6	19.6

Abbreviations and symbols:

	PM	Permanent Magnet
	HYB	Hybrid
	EM	Electomagnetic
	SC	Superconducting
	Ky, Kh, Kx	deflection parameter for horizontal, circular and vertical polarization modes

The insertion devices can be divided in three categories:

Conventional (vertical field) undulators and wiggler. They represent the 'first generation' of magnets built for ELETTRA, and provide fixed polarisation.
The Electromagnetic Elliptical Wiggler (EEW). Designed to allow circular polarisation with fast helicity switching.
Elliptical undulators. The development of these 'second generation' devices was stimulated by strong users' demand for variable polarisation sources.

Also shown in red in the above table are two new magnets (presently under construction):

The Figure-8 undulator (FEU), a source of low energy (5 eV) photons with reduced on-axis power compared to a conventional device. It will be used for Inelastic UV Scattering experiments.
The Superconducting Wiggler (SCW), which will extend the useful spectrum at high energies (>10 KeV) for X-Ray Diffraction applications.

Additionally, a prototype short undulator has been recently completed. It will be installed in a dispersive section as a test of the feasibility of adding new radiation sources in the short straights of the storage ring.

Operative Unit

Insertion Devices

Contacts