Accelerator Magnet Technology Division


Indus-1 is a 450 MeV storage ring designed to provide radiation in the range 30 - 2000 Å. It is a small ring having a circumference of 18.96 m. The critical wavelength of the radiation emitted from its four 1.5 T bending magnets is 61 Å. The machine was put regular operation on 26th of September 2002.

The magnetic lattice of the ring consists of 4 super periods, each having one dipole magnet with a field index of 0.5 and two doublets of quadrupoles. The field index of 0.5 in the dipole magnets helps in achieving a larger stability range because it provides weak focussing in radial and vertical planes. Each super-period has a 1.3 m long straight section.

To correct the natural chromaticity of the ring, which arises due to different focusing of different energy particles, is corrected using a pair of sextupoles in each super period. The sextupole field gives rise to nonlinear kicks to the beam.

Major parameters of Indus-1 Dipole magnet

Aperture gap                                                  

  50 mm
Good field region x=± 35mm, z = ± 12.5 mm


1.5 T
Bending angle 90°
Bending radius 1.0 m
Field index   0.5 (± 0.01 random)

Major parameters of Indus-1 Quadrupole magnet

Aperture radius                                    

40 mm

Good field region                                             

x=± 35mm, z = ± 12.5 mm

Quadrupole integrated strength

Qf        -6.0 m-2
Qd       9.0 m-2

Major parameters of Indus-1 Sextupole magnet

Aperture radius

90 mm

Good field region

x=± 35mm, z = ± 12.5 mm

Sextupole integrated strength

Sf         -4.0 m-2
Sd        4.0 m-2

All these magnets were designed using 2-D POISSON/PANDIRA code. Magnetic measurements of Dipole magnets were carried out using Hall probe mounted on a 2-axis computer controlled machine. The quadrupole and sextupole magnets were characterized by using a rotating coil system made by DANFYSIK model 690.

Best viewed in 1024x768 resolution