Date: Thu, 23 Feb 2012 11:07:59

Author: Paul Nord

Subject: Re: What "Math" Demos among the Physics Demos Do You Like?

Post:

Do you have the raw data? A list of times between successive events? Or, even more basic, we could look at the time each event was collected.

Excel is a horrible tool for making a histogram. (Does anyone have a connection with Microsoft who can bend an ear about this? Spreadsheet programs have always done a bad job with scientific data analysis. Get them to port the Analysis Toolkit to Mac as they promised to do three versions ago.)

Paul


On Feb 23, 2012, at 9:34 AM, George Herold wrote:

> Hi Jerry, OK no plot, but here's the raw data made into 20 uS bins.
>
> Bin Frequency
> 0 0 12
> 20 20 120
> 40 40 108
> 60 60 121
> 80 80 96
> 100 100 102
> 120 120 97
> 140 140 84
> 160 160 98
> 180 180 78
> 200 200 87
> 220 220 87
> 240 240 105
> 260 260 93
> 280 280 96
> 300 300 78
>
> The way excel does bins is a bit weird (for me.) So the first number at
> zero (12) is the number of counts with 'zero' time... Times less than 1
> us. At some point this bin has to be a little lower than expected,
> 'cause of time limits somewhere else in the system. I think the counter
> has a 'dead time' of maybe 20-30 ns. It depends on how 'fat' a pulse
> you send into it....
>
> So then the second bin is number of counts between 1 and 20 us
> Then 21 to 40
>
> Etc.
>
> George H.
>
>> -----Original Message-----
>> From: tap-l-owner@lists.ncsu.edu
>> [mailto:tap-l-owner@lists.ncsu.edu] On Behalf Of Jerry DiMarco
>> Sent: Wednesday, February 22, 2012 5:30 PM
>> To: tap-l@lists.ncsu.edu
>> Subject: Re: [tap-l] What "Math" Demos among the Physics
>> Demos Do You Like?
>>
>> The article states there were nearly 1000 occurrences
>> of time intervals in the 1-200 usec. range. I'd like to see
>> the distribution in that range...
>>
>>
>> Jerry D
>>
>>
>> At 2/22/2012 04:13 PM, you wrote:
>>> Ahh don't you have a guess?
>>>
>>> The most common time between counts is independent of the count rate.
>>> (That's the trick part.) The most common time is zero and
>> exponentially
>>> decreasing from there.
>>>
>>> See figure 14 on the last page of this newsletter.
>>>
>>> http://www.teachspin.com/newsletters/TeachSpin_FEB1_Hat%20Trick.pdf
>>>
>>> George H.
>>>
>>>> -----Original Message-----
>>>> Well, it doesn't look like anyone is going to bite.
>>>> Please don't keep us on the edge of our seats...
>>>>
>>>>
>> Jerry D
>>>>
>>>> At 2/21/2012 10:17 AM, you wrote:
>>>>> ......
>>>>> Here's a 'trick' question.
>>>>> If the count rate is 1000 counts per second what is the most
>>>> common time
>>>>> between counts?
>>>>>
>>>>> George H.
>>>>>
>>>>> (Don't worry I would have answered this question wrong a few
>>>> years ago.)
>>
>>
>>
>



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