21A1 U90 - (White Light) Chemical Dynamics (PRT 75%)


Crossed Molecular Beam Machine
The crossed molecular beam machine established at 21A end station consists of three main parts: two rotatable source chambers, a reaction chamber, and an ion detector. The two source chambers fixed at 90o to each other are rotatable from –20o to 110/sup>o relative to the ion detector. For bimolecular reactions two molecular beams cross in the reaction chamber and for photodissociations a photolysis beam intersects a molecular beam. Reaction products after 10-cm free flight are ionized using synchrotron radiation. The desired ions are selected with a quadrupole mass filter and detected with a Daly-type ion counter. As a liquid nitrogen cooler combined with a He-refrigerator is used, the vacuum in the ionization region can be suppressed down to 5 x 10-12 Torr which dramatically increases the signal-to-noise ratio in H2 detection.
Application of VUV Synchrotron Radiation in the Chemical Dynamic Research,

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+886-3-578-0281 Ext. 1211

BL Spokesperson

Lee, Shih-Huang (李世煌)
+886-3-578-0281 Ext. 7317

BL Manager/Local Contact

Chou, Yi-Ming (周弈銘)
+886-3-578-0281 Ext. 3269


  • X-ray Photoelectron Spectroscopies (XPS)


  • Biochemistry

General Information

  • Source: U90
  • Energy Range: 0.5-0.05 eV
  • Focused Spot Size: 1 × 1 mm
  • Status: Operational

National Synchrotron Radiation Research Center

101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu, Taiwan 30076