1. Design and construction of SMART Presented by Seigo Kato Nov. 12, 2005 http://www.quark.kj.yamagata-u.ac.jp/~kato

2. Characteristics of a fixed-angle spectrometer Advantages cascade mode selectable resolution future extension (3-rd dipole) zero-degree measurement (beam stop at first stage) trace back to the target by double position detection no need of rotation mechanism and space heavy shield for detectors neutron TOF Disadvantages need of beam swinger need of arbitrary-angle twister beam dump to be discussed in this report

3. Layout of the experimental halls The concrete is not strong here.

4. Layout of SMART

5. Selectable resolution 41 % 20 msr 1/4000 4 % 10 msr 1/13000

6. Possible extension: a super-high-resolution mode

7. Ray-tracing

8. Beam swinger For the angular dependence measurements, the incoming beam direction is changed instead of the outgoing particle direction. pre-assembling at manufacturer’s factory configuration: DQQD bending: - 45 and +135 deg designed by H. Shimizu

9. Arbitrary-angle beam twister Because the direction of the dispersion in the beam swinger has to be within the median plane, we need a beam image rotator for arbitrary angles. effect of rotator S(  ) invert-rotator T(  )

10. before inversion after inversion Graphical understanding of the invert-rotator T(  ) is easy to obtain and is not inferior toas a rotator.

11. vertical inverter Trotation matrix R of the reference system invert-rotator T(  ) Calculation

12. Q-triplet is an incomplete inverter because we cannot specify * ’s. A Q-septet rotated by  /2 can rotate the beam image by  after vertical inversion. Q-septet is a complete inverter. reference: S. Kato, Nucl. Instr. & Meth. A254(1987)487 How to make a vertical inverter

13. Asymmetric quadrupole magnets between horizontal and vertical directions Bottom yokes of Q 1 and Q 2 are open for the beam dump. Q1Q1 Q2Q2 Q3Q3 left halves: field line curves right halves: field strength contours (convenient for Q-magnets)

14. Quadrupole magnets before installation Q 1 magnet being painted Q 3 (left) and Q 2 (right)

15. Total system installed

16. reference: T. Ichihara et al, Nucl. Phys. A569(1994)287c Performances

17. What was SMART for me from technical viewpoint? A big challenge to overcome many problems Hints to subsequent spectrometers QQD spectrometers such as BBS, HKS, HES fixed spectrometer proposed for GSI eA-collider Farewell to SMART I would like to express my thanks to the collaborators