Talk:Proportional counter

Untitled

I removed the reference to the 'inventor' of the proportional counter. However, proportional counters were used and so titled for at least a few years before the date given for invention. When a person reads that line, they will be left with the idea that the proportional counter wasn't in existence before 1948, which simply isn't true. Here is a link showing a paper from 1942 as an example of earlier usage. --Mccreary (talk) 03:36, 15 June 2011 (UTC)

I have rewritten quite a bit of this page. The article implied that G-M tubes make use of the avalanche effect but proportional counters do not. In fact, both make use of the Townsend avalanche. The difference is that in a proportional counter, the proportionality between the energy deposited by the original event and the energy detected is preserved. In a G-M tube this proportionality is not preserved. I thought that this was an important point to make.

I also removed

"(a metal wire in the middle of a metal can is positive electrode and the metal can itself is grounded, i.e. it is the zero-voltage electrode)"

since I don't think it really made things any clearer.

Perhaps in the future it would be good to have a chart of pulse amplitude against applied voltage, showing the region of proportionality etc Mumby 23:33, 6 June 2006 (UTC)

Much better now.

I also think if you mention the gain/voltage relation, the article might then also benefit from a mention of some important variants of the Prop counters: position-sensitive and multiwire devices, and also alternate methods of generating high field gradients, such as microdots and microstrips. The article has the potential of getting specialised at that point, but I feel it's important to hint at the variety. Matt Whyndham 16:02, 31 August 2006 (UTC)

The charge is proportional to the deposited energy, not to the kinetic energy of the incident particle. The energy deposited by an incident particle is related to its velocity by the Bethe-Block formula. So it is not true that "By measuring the total charge (time integral of the electric current) between the electrodes, we can find out the particle's kinetic energy, because the number of ion pairs created by the incident ionizing charged particle is proportional to its energy." I think the aforementioned sentence should be removed. —Preceding unsigned comment added by 18.101.16.100 (talk) 20:42, 26 November 2010 (UTC)

Particles, charged particles, and elementary particles

I changed the 'particles' link from elementary particles to the charged particles stub. This is not an ideal solution, but I thought it was important not to imply that elementary particles are the only kind of ionising radiation that a proportional counter might be designed to measure. Mumby 12:23, 20 July 2006 (UTC)

Various improvements

Three new graphics have now been created and added to show the relation of the prop counter to other gasous counters and explain the mechanism of proportionality.Dougsim (talk) 10:16, 31 October 2012 (UTC)

Assessment comment

The comment(s) below were originally left at Talk:Proportional counter/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

Rating Justification: No references, graphics or quantities. No indication of chronology and relative age (obsolescence?) of the technology. Matt Whyndham 14:46, 25 January 2007 (UTC)

Last edited at 14:46, 25 January 2007 (UTC). Substituted at 03:27, 30 April 2016 (UTC)