Two methods for the measurement of the uniformity of the refractive index n within a single block of silica aerogel are described. One is based on the deflection of a laser beam induced by transverse index gradients. The second exploits the Cherenkov effect, measuring the emission angle of photons radiated by 500 MeV electrons traversing the aerogel. The beam can scan the full aerogel surface providing information on point to point variations of n. The measurement of the dispersion law n (λ) is also reported. An Xe lamp coupled to a diffraction grating provides the monochromatic source. The index for each λ is measured by the prism method at a corner of an aerogel sample. A Sellmeier functional form for n (λ) is assumed, and the parameters best fitting the experimental data are given.

Bellunato, T., Calvi, M., Matteuzzi, C., Musy, M., Perego, D., Storaci, B. (2008). Refractive index of silica aerogel: Uniformity and dispersion law. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT, 595(1), 183-186 [10.1016/j.nima.2008.07.072].

Refractive index of silica aerogel: Uniformity and dispersion law

BELLUNATO, TITO FLAVIO
Primo
;
CALVI, MARTA
Secondo
;
MATTEUZZI, CLARA;MUSY, MARCO;PEREGO, DAVIDE LUIGI
Penultimo
;
2008

Abstract

Two methods for the measurement of the uniformity of the refractive index n within a single block of silica aerogel are described. One is based on the deflection of a laser beam induced by transverse index gradients. The second exploits the Cherenkov effect, measuring the emission angle of photons radiated by 500 MeV electrons traversing the aerogel. The beam can scan the full aerogel surface providing information on point to point variations of n. The measurement of the dispersion law n (λ) is also reported. An Xe lamp coupled to a diffraction grating provides the monochromatic source. The index for each λ is measured by the prism method at a corner of an aerogel sample. A Sellmeier functional form for n (λ) is assumed, and the parameters best fitting the experimental data are given.
Articolo in rivista - Articolo scientifico
Cherenkov detectors; Silica aerogel
English
183
186
4
Bellunato, T., Calvi, M., Matteuzzi, C., Musy, M., Perego, D., Storaci, B. (2008). Refractive index of silica aerogel: Uniformity and dispersion law. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT, 595(1), 183-186 [10.1016/j.nima.2008.07.072].
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/155108
Citazioni
  • Scopus 22
  • ???jsp.display-item.citation.isi??? 16
Social impact