Ottimizzazione dei materiali per la rivelazione simultanea di luce Cherenkov e di scintillazione Elena Vannuccini Elena Vannuccini 20/06/2014
Outline Ulteriore riflessione sulle proprietà del materiale scintillante necessarie per un’efficiente rivelazione della luce Cherenkov Materiali commerciali, selezionati da cataloghi di alcune ditte: Amcrys, Crytur, Scionix, Detec, Scientific Materials, Saint- Gobain…altri suggerimenti? Scopo: acquistare alcuni campioni per fare dei test mirati Elena Vannuccini 20/06/2014
Cherenkov radiation 𝛽> 1 𝑛 𝑠𝑖𝑛 2 𝜃 𝐶 = 1− 1 𝛽 2 𝑛 2 Velocity threshold 𝛽> 1 𝑛 Directional emission 𝑠𝑖𝑛 2 𝜃 𝐶 = 1− 1 𝛽 2 𝑛 2 Emission spectrum Frank-Tamm formula energy emitted per unit length dx and per unit of angular frequency dω 𝑑𝐸= 𝑍 2 𝑒 2 4𝜋 𝜇 𝜔 𝜔 1− 1 𝛽 2 𝑛 2 𝜔 𝑑𝑥𝑑𝜔 Elena Vannuccini 20/06/2014
Amount of Cherenkov radiation in dielectric media Number of emitted photons 𝑑 𝑁 𝛾 by relativistic particles per unit of w.l. d𝜆 and unit of lenght 𝑑𝑥 𝑑 𝑁 𝛾 ∝ 1− 1 𝑛 2 𝜆 1 𝜆 2 𝑑𝜆 𝑑𝑥 𝑑 𝑁 𝛾 𝑑𝜆 𝑑𝑥 ≈460 ∙ 𝑍 2 𝑠𝑖𝑛 2 𝜃 𝐶𝑚𝑎𝑥 𝜆 𝜇𝑚 2 ∙ 𝜇𝑚 −1 𝑐𝑚 −1 depends on 𝜆 −2 depends on the refractive index of the medium (NB: the light emission for a e+e- pair at close distance (< 1 w.l.) is suppressed comprared to two independent leptons) Elena Vannuccini 20/06/2014
Refractive index vs wavelenght Atomic resonances (absorption) Silica glass Elena Vannuccini 20/06/2014
Refractive index of pure crystals NB! Refractive index of pure crystals ~50% Elena Vannuccini 20/06/2014
1.5X0 Mao,Zhang&Zhu – IEEE TNS 355 (2008) 2425 Elena Vannuccini 20/06/2014
? Mao,Zhang&Zhu – IEEE TNS 355 (2008) 2425 Excitation spectrum Photo-luminescence spectrum Measured transmittance Theoretical limit (internal reflection) Elena Vannuccini 20/06/2014
Mao,Zhang&Zhu – IEEE TNS 355 (2008) 2425 Excitation spectrum Photo-luminescence spectrum Measured transmittance Theoretical limit (internal reflection) Elena Vannuccini 20/06/2014
Refractive index of pure crystals NB! Refractive index of pure crystals BaF2 BGO CsI:Tl Elena Vannuccini 20/06/2014
CsI: Tl-doped, Na-doped, pure Mao,Zhang&Zhu (2008) Absorption cut-off (nm) 50% emission @800 nm Luminescence (nm) CsI:Tl 340 358 550 CsI:Na 300 318 420 CsI 260 280 310 Elena Vannuccini 20/06/2014
Refractive index of pure crystals NB! Refractive index of pure crystals ? CsI CsI:Na CsI:Tl Elena Vannuccini 20/06/2014
Solar-netrino detection Elena Vannuccini 20/06/2014
YAG:Yb Belogurov et al. – NIM A 516 (2004) 48 Elena Vannuccini 20/06/2014
Refractive index of pure crystals BaF2 NB! Refractive index of pure crystals YAG:Yb BGO CsI:Tl Elena Vannuccini 20/06/2014
YAP:Yb Belogurov et al. – NIM A 516 (2004) 48 Elena Vannuccini 20/06/2014
LuAG:Yb Belogurov et al. – NIM A 516 (2004) 48 Elena Vannuccini 20/06/2014
(spessori sottili…) Elena Vannuccini 20/06/2014
Crytur materials Elena Vannuccini 20/06/2014
Crytur materials 0.5 mm 1.0 mm 2.5 mm Elena Vannuccini 20/06/2014
Crytur materials Elena Vannuccini 20/06/2014
Refractive index of pure crystals NB! Refractive index of pure crystals YAG:Yb YAG:Ce Elena Vannuccini 20/06/2014
Good for detecting neutrons! Amcrys materials Good for detecting neutrons! Elena Vannuccini 20/06/2014
Elena Vannuccini 20/06/2014
Elena Vannuccini 20/06/2014
Van Eijk- NIMA-460(2001)1 Elena Vannuccini 20/06/2014
Scionix materials Elena Vannuccini 20/06/2014
DETEC materials Elena Vannuccini 20/06/2014