Low reflective index silica aerogel was developed by Chiba University group. Low reflective index silica aerogel was developed by Chiba University group

Low reflective index silica aerogel was developed by Chiba University group.

• Low reflective index silica aerogel was developed by Chiba University group.

• To use as AC veto Counter, we tested this sillica aerogel by beam at LEPS .

• 2008/4/21,22
• Tabata, Saito, Kawai, Chiba University, Kon

• Detection efficiency and mean # of photoelectron was estimated about index n = 1.015, 1.0082 and 1.0027.

Aerogel Counter:

• Aerogel Counter:

• Cerenkov effect
• Photomultiplier
• Emission of photoelectrons from cathode obey Poisson statistics.

• Detection efficiency:

Light guide box: width 125 x hight 260 x thickness 65

• Light guide box: width 125 x hight 260 x thickness 65

• Covered by reflector Alminized mylar & Gore-tex sheet.

• 4 Photomultiplier: Fine mesh type (Hamamatsu Photonics H6614-70)

• Aerogel was arranged by hangging in midair by strings.

Cerenkov angle:

• Cerenkov angle:

• Beam: electron

• In very low index point, Cerenkov angle is a few degrees.

n=1.015

• n=1.015