LAPPD Figures for Papers and Talks

June22 v11 rev102 gaussfit final

73

The single-PE transit-time spread measured for the $\LAPPD$ stack inside the 8" chamber, derived using the gaussian fit method. The RMS of the arrival times is 63 psec, and the fitted sigma is 56 psec.

June22 v11 rev102 cftfit final

72

The single-PE transit-time spread measured for the $\LAPPD$ stack inside the 8" chamber, derived using the CFD algorithm. The RMS of the arrival times is 67 psec, and the fitted sigma is 56 psec. Given the inherent limitations of these fit methods, the non-Gaussian character of the reconstructed TTS and wider tails compared to the template fit are expected.

Sampletrigtrace

71

An example oscilloscope trace including both the trigger diode and the UV photodiode.

Samplepulse

70

An example of an MCP pulse.

Singlepephd v5

69

he pulse height distribution for a pair of MCPs in single PE mode, overlaid with a polynomial fit to the shape.

Tilebases

68

A pair of demountable tile bases from Joe Gregar (ANL Glass Shop). These consist of a glass sidewall fritted onto a 30-strip `Frugal' glass anode and are used with an O-ring sealed window to test the MCP-spacer stack of the Frugal tile at the APS laser facility. The pump ports are reinforced for mechanical strength.

Fft fixed

67

Frequency spectrum of the MCP signal plus noise (solid red) overlaid on the pure noise spectrum (dashed blue). Signal dominates over noise only up to around 500 MHz.

8inchschematic

66

A schamatic illustration of the 8" MCP test-chamber.

Qecurve

65

Probability of the Ti::Sapphire laser pulse generating an MCP signal on the aluminum photocathode, plotted as a function of pulse energy. At sufficiently high laser intensities, this probability approaches unity; as the laser is attenuated below roughly 10 million UV photons per pulse, the fraction of laser pulses producing an MCP signal begins to drop and eventually approaches zero.

Moneyplot both

64

Differential time resolution as a function of
Noise/Signal, plotted for data collected using the Demountable detector in 2014 (red squares)
and the 8" chamber in 2012 (black circles). Error bars are smaller than the marker size. The intercept of fitted line intersects at 1.6 psec.