What makes a Geiger_counter tick?

[Capiert]

 

What is radioactivity?

What is (electrical) insulation?

(Are they opposites? e.g. oppositely proportional?)

 

 

Marie & Pierre Curie

 measured (& compared)

 the amount "time"

 in seconds

 (from a distance)

 that their (charged) capacitor

 discharged (e.g. (to) half its voltage).

 

(The sooner their capacitor was discharged, (meant)

 the more radioactive

 the location was.

=Less (discharging) time

 meant more radioactivity.)

 

A Geiger_Mueller (GM) tube

 is something like

 a piece of coax wire

 acting like a((n air, or gas filled) charged, but

 dischargeable)

 capacitor.

 

(A high voltage supply

 repeatedly recharges

 the capacitor.)

 

(I'll ignore the window on some tube's end,

 but that (window)

 exposes the inner electrode

 to electromagnetic fields

 (e.g. no shielding)).

 

Basically:

The electronics ((audio) amplifier, (like from a stereo music player))

 produces an acoustic signal,

 a "click",

 from a(n input) voltage spike.

 

I've touched the (shielded)

 inside electrode

 of the (GM) tube

 with my finger

 & the amplifier just whistles

 (many "clicks" per second).

 

(Perhaps due to the (background) electromagnetic noise

 on me as a (charged) capacitor

 based on my size, e.g. (as) surface area.?)

 

It seems like

 the air's (electrical insulation) insulating properties

 break down;

 or that an extra voltage

 is (temporarily) present

 that adds

 to lower the (total, insulating) breakdown voltage.

 

That means (to me) a zener diode

 (with its voltage held near (=just below) max breakdown voltage)

 could be used instead,

 but needs a large surface (area)

 (acting like a chargeable capacitor).

 

I've connected a doubled_sided copper circuit board

 to a zener diode,

 acting like a capacitor('s area) in parallel,

 & the background (radiation) count (=clicks rate)

 went up.

 

(I've also done the same with a small GM tube (instead of zener diode)

 & had the same results: click rate increased

 depending on the capacitor plates' size.)

 

I've also noticed

 that the click rate increases (wildly)

 when the Geiger counter (tube)

 gets near a (kopfball) spherical (positive) high_voltage

 vacuum glass discharge lamp=light.

 

(I assume that exposed high voltage (glass) electrode

 is positive(ly charged).)

 

This thread('s question) is more about

 what is (the nature of) radioactivity

 (e.g. ruining electrical insulation),

 considering that we (indirectly) measure that (radioactivity)

 with (simple) electromagnetic instruments (instead).

 

E.g. although we measure voltages (spikes, or pulses),

 they are (really) produced by tiny (electrical) currents.

 

& (=But the whole idea brings up the question:)

 what is electrical insulation?

 

 .. because radioactivity is affecting that (electrical insulation).

 

 

 

Edited November 18, 2017 by Capiert

[studiot]

1967 I built my first geiger.

Gosh was it that long ago? I don't think I even own one now.

 

Anyway here is a good simple explanatory article.

Don't forget geiger tubes use high voltage, when you are thinking about radioactivity.

Yes readioactivity does degrade insulation over time.

[Sensei]

Quote

What makes a Geiger counter tick?

Simplifying, some radioactive decay produces highly accelerated charged particles.

When they pass through medium, they ionize atoms and molecules, and electrons from medium are ejected.

When you will charge capacitor (two electrodes, one will have abundance of electrons, second one will have absence of electrons), and start ionizing medium between them,

current will flow through medium closing your circuit. Use this information for transistor to increase power and then further to speaker, and you have radioactivity meter.

It takes time to load capacitor, it takes some time to discharge capacitor. So it does not tick at every single event on quantum level.

 

Air medium requires high voltage, that's why in circuit presented by Studiot, there is voltage amplifier.

1 hour ago, Capiert said:

 

This thread('s question) is more about

 what is (the nature of) radioactivity

 (e.g. ruining electrical insulation),

 considering that we (indirectly) measure that (radioactivity)

 with (simple) electromagnetic instruments (instead).

Radioactivity can cause ionization of atoms and molecules.

That's the same like with Cloud Chamber.

 

These traces are visible just because electric charged particles passed through medium, ionizing it.

Electric neutral particles don't leave traces.

 

1 hour ago, Capiert said:

 

I've also noticed

 that the click rate increases (wildly)

 when the Geiger counter (tube)

 gets near a (kopfball) spherical (positive) high_voltage

 vacuum glass discharge lamp=light.

Which gas is ionized in your discharge tube?

They produce UV ionizing photons.

 

ps. Why is it in Speculation? So far there was no speculation (and I hope so it'll remain this way!), so it should be in mainstream physics section instead.

ps2. +1 for interesting subject to discuss.

 

Edited November 18, 2017 by Sensei

[Capiert]

1 hour ago, studiot said:

1967 I built my first geiger.

Good stuff.

Quote

Gosh was it that long?

I guess so. (Time will tell.)

Quote

I don't think I even own one now.

I purchased a proportional counter too

 because I was fascinated

 by the linear (distance) response

 of a wire

 between a parallel plate capacitor;

 instead of GM coax form.

Quote

Anyway here is a good simple explanatory article.

The author's name looks like a distant relative.

Quote

Don't forget geiger tubes use high voltage, when you are thinking about radioactivity.

Can you elaborate (please)?

Quote

Yes readioactivity does degrade insulation over time.

I was more concerned with the (instant) real_time phenomena,

 

 (the opposite of what you (all) call ionization, i.e. electrical insulation, (atomic work potential?)

 e.g. what makes an atom insulate (electricity)?

What is (electrical) insulation?

E.g. What is resistance, atomically?

Why do things insulate (electrically)?)

 

 not necessarily the (long_term) accumulated damage.

Perhaps that's why Senei did NOT recognize my speculation?

The breakdown voltage decreases

 near radioactivity (=a radioactive substance)

 but recovers (almost instantly=immediately, after)

 when the radioactive substance

 is removed (=taken far away);

 (excluding that little bit of the GM tube

 that remains radioactive).

Quote

The authors name looks like a distant relative.

Thanks for the article.

Edited November 18, 2017 by Capiert

[Sensei]

16 minutes ago, Capiert said:

 

Perhaps that's why Senei did NOT recognize my speculation?

The breakdown voltage decreases

 near radioactivity (=a radioactive substance)

 but recovers (almost instantly=immediately, after)

 when the radioactive substance

 is removed (=taken far away);

 

It's inverse square law.

https://en.wikipedia.org/wiki/Inverse-square_law

Unstable point particle can decay randomly uniformly in the all directions. When they pass through medium, they ionize it, and electrons from negatively charged electrode find path through medium (air or other gas typically), to positive electrode. Yes, smaller breakdown voltage is needed to initiate flow of electrons. Because there are electric charged particles in medium, which helps electrons to flow through it.

 

Edited November 18, 2017 by Sensei

[Capiert]

11 minutes ago, Sensei said:

 

It's inverse square law.

https://en.wikipedia.org/wiki/Inverse-square_law

Unstable point particle can decay randomly uniformly in the all directions. When they pass through medium, they ionize it, and electrons from negatively charged electrode find path through medium (air or other gas typically), to positive electrode. Yes, smaller breakdown voltage is needed to initiate flow of electrons. Because there are electric charged particle in medium, which helps electrons to flow through it.

 

Yes, but I'm still asking what resistance & insulation are.

E.g. With radioactivity

 some of that resistance

 & insulation does NOT exist.

 

Without radioactivity

 the insulators (will) insulate (again)

 as normal (=natural).

Edited November 18, 2017 by Capiert

[Sensei]

16 minutes ago, Capiert said:

Yes, but I'm still asking what resistance & insulation are.

It's experimental physics. You read it from the table. Different mediums, different gases, different mixtures of gases, will have slightly different breakdown voltage. It'll also change with pressure, so at altitude 10 km it won't be the same as here on the ground. It's often used in obsolete electronics, vacuum tubes (or with some gas evacuated partially) - decrease gas pressure and have smaller voltage needed to cause flow of electrons. Just buy vacuum pump ($300-$500) on eBay or lab equipment store and you will be playing with it. High voltage you can make using Cockcroft-Walton generator. Different quantity of diodes - different voltage.

 

Edited November 18, 2017 by Sensei

[Capiert]

1 hour ago, Sensei said:

Simplifying, some radioactive decay produces highly accelerated charged particles.

When they pass through medium, they ionize atoms and molecules, and electrons from medium are ejected.

When you will charge capacitor (two electrodes, one will have abundance of electrons, second one will have absence of electrons), and start ionizing medium between them,

current will flow through medium closing your circuit. Use this information for transistor to increase power and then further to speaker, and you have radioactivity meter.

It takes time to load capacitor, it takes some time to discharge capacitor. So it does not tick at every single event on quantum level.

 

Air medium requires high voltage, that's why in circuit presented by Studiot, there is voltage amplifier.

Radioactivity can cause ionization of atoms and molecules.

That's the same like with Cloud Chamber.

 

These traces are visible just because electric charged particles passed through medium, ionizing it.

Electric neutral particles don't leave traces.

 

Which gas is ionized in your discharge tube?

I'll assume it's (evacuated) air.

Otherwise no info available.

1 hour ago, Sensei said:

They produce UV ionizing photons.

I guess so,

 the arcing is blue,

 & fleshy magenta

near the glass when touching

 ~10 cm outer glass ball.

1 hour ago, Sensei said:

ps. Why is it in Speculation? So far there was no speculation (and I hope so it'll remain this way!), so it should be in mainstream physics section instead.

I'm trying to figure out what insulation is,

 & e.g. why radioactivity changes that.

I'm afraid they might send me back here,

 because it's NOT a typical explaination

e.g. (radioactivity) wrt insulation.

 

Judging from detector response with repect to

 touching the middle electrode,

 & the positive discharge lamp,

I get the idea

that radioactivity might have a large positive

charge_density.

We know the nucleus is largely positive (protons).

It's also interesting,

 that oil (an insulator) (also wax)

can stop some (nuclear) radiations (a bit).

1 hour ago, Sensei said:

ps2. +1 for interesting subject to discuss.

Thanks.

[Sensei]

Quote

2 hours ago, Sensei said:

Which gas is ionized in your discharge tube?

I'll assume it's (evacuated) air.

Otherwise no info available.

Discharge tubes are filled by gas. Different colors, different gases.

14 minutes ago, Capiert said:

I guess so,

 the arcing is blue,

 & fleshy magenta

near the glass when touching

 ~10 cm outer glass ball.

Are you talking about plasma globe.. ?

https://en.wikipedia.org/wiki/Plasma_globe

"Although many variations exist, a plasma lamp is usually a clear glass sphere filled with a mixture of various gases (most commonly neon, sometimes with other noble gases such as argon, xenon and krypton) at nearly atmospheric pressure."

 

Edited November 18, 2017 by Sensei

[Capiert]

2 hours ago, Sensei said:

Discharge tubes are filled by gas. Different colors, different gases.

If I didn't know better,

 I'd say it's N2.

Quote

Are you talking about this?

https://en.wikipedia.org/wiki/Plasma_globe

Yes, exactly!

Quote

"Although many variations exist, a plasma lamp is usually a clear glass sphere filled with a mixture of various gases (most commonly neon, sometimes with other noble gases such as argon, xenon and krypton) at nearly atmospheric pressure."

That globe makes my proportional detector whistle!

Like when touching the (detector's) inner electrode with my finger.

(Wrongly?) interpretted, that means both (globe; & finger) are radioactive. (?)

They produce similar results on the detector,

 that radioactivity would.

 

But I have not reversed the experiment:

 I have not brought a radioactive source near (only) the globe.

I would expect the globe would go crazy,

 conducting, with much more light

 (near(est) the source).

Edited November 18, 2017 by Capiert

[Sensei]

1 hour ago, Capiert said:

(Wrongly?) interpretted, that means both (globe; & finger) are radioactive. (?)

No. Geiger is detecting ionization. It does not tell what is source of ionization.

Organic matter (your body) is slightly radioactive because of presence of radioactive isotopes of Carbon-14 and Potassium-40.

Either Carbon-14 and Potassium-40 are decaying via beta decay minus, emitting electron and antineutrino (ionizing radiation).

 

1 hour ago, Capiert said:

If I didn't know better,

 I'd say it's N2.

Do you have prism? Try splitting light to see spectral lines..

 

Plasma globe is toy, but discharge tubes are equipment for scientists-to-be.

Light from them you split on prism to see spectral lines.

 

 

Edited November 18, 2017 by Sensei

[studiot]

Like the pics of the discharge tubes, thanks +1 Sensei.