Online Muon Capture and Decay Experiment

Megan Alexander, Daniel Miner, Wojtek Skulski, Frank Wolfs

University of RochesterWork funded by a grant from the APS WYP

2005 and a grant from the NSF.

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Overview

Purpose: To capture and share data from cosmic muons, making a “real” physics experiment accessible to the public.

In this talk:Experimental detailsWebsite tour

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Motivation

Time dilation (special relativity)Classic experiment, popular in advanced physics labsOutreachMount Washington, NH

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Detector(Scintillator + PMT)

Experiment Setup

InternetInternet

DDC-8 Circuit Board

(DSP)

Cosmic Muons

ToolsXilinxCypress EZ-USB

BlackBoxApache

XML/SWF Charts

AWStats

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DDC-8Developed by Wojtek Skulski.

Diagnostic OUT40 MHz * 10 bits

JTAG connector

FPGA

ADC 40 MHz * 10 bits (8 channels)

16 bidirectional TTL lines + 1 in(pool of extra logic I/O)

Analogsignal IN8 channels (only 1 used)withdigital offsetand gain control

RS-232

Logic connectors NIM 16 lines IN, 8 lines OUT

USB

RAM500 kB

ECL clock IN(optional)

microprocessor

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Typical Muon Signals

Stopping Muons:Passing Muons:

μ+

μ+

e+

μ+

ve

μ+

vμ

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Web View: Waveforms

Time constant: 2.1 μs

http://wolfspc.pas.rochester.edu/muon/daq.html

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Web View:Energy Spectra

http://wolfspc.pas.rochester.edu/muon/EnergySpectra.html

• Conventional muon lifetime experiments do not exploit DSP for particle ID: this one does!

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Downloadable Data

http://wolfspc.pas.rochester.edu/muon/DLData.html

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Downloadable Data

View from Excel, MATLAB

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Summary and Conclusion

Physics outreach enabled by hardware, software, web tools.Total unique visitors: