Author Topic: soft x-ray generation and measurements  (Read 5240 times)

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Re: soft x-ray generation and measurements
« Reply #9 on: February 26, 2017, 17:25:18 pm »
steve the xray detection principle may be the same as the geiger counter but maybe the range is not favorable...

a tube having a noble gas will ionize under xray making the gas conductive... measuring the change in resistance would be a way to detect the xrays but mainly this detectors works with stages to be more sensitive... called multipliers

another way to do it is with photoelectric measurements, you also need a tube that has a filament covered with a low workfunction material so apply a voltage to the plate and measure the current when xray come there should be a current

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Re: soft x-ray generation and measurements
« Reply #10 on: March 01, 2017, 19:19:22 pm »
X-ray production whenever electrons of high energy strike a heavy metal target, like tungsten or copper. When electrons hit this material, some of the electrons will approach the nucleus of the metal atoms where they are deflected because of there opposite charges (electrons are negative and the nucleus is positive, so the electrons are attracted to the nucleus). This deflection causes the energy of the electron to decrease, and this decrease in energy then results in forming an x-ray.

Another one:
You can also get some X-ray production via field emission, whereby electrons escape a cold metal due to very high local electric fields (the Schottky effect).

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Re: soft x-ray generation and measurements
« Reply #11 on: March 02, 2017, 05:21:28 am »
I  got a course at the university about chemistry of radiation i learned about ionizing radiation of many types and xray was part of it, from what i remember the electrons get into the metal electrosphere and knock out an electron at a inner orbit so the atom is not it is not stable so an electron from an upper orbit must go down to the inner orbit thereto it will  emit the xray , its energy will depend on the orbital reached..

another way to generate xrays is to use particle accelerators and an arrange of magnetic fields to make the particle oscillate and emit radiation.

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Re: soft x-ray generation and measurements
« Reply #12 on: March 02, 2017, 09:47:29 am »
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Re: soft x-ray generation and measurements
« Reply #13 on: March 03, 2017, 13:19:22 pm »
Dear all, here some valuable information.
I measured with my geiger counter a radiation coming of the HV unit with sparkgap. The gap radiates.
The bigger the gap the longer distance the radiation reaches.

1mm gap = 3.5cm distance
1cm gap = 11 cm distance
2cm gap = 19 cm distance

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Re: soft x-ray generation and measurements
« Reply #14 on: March 03, 2017, 14:24:45 pm »




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Re: soft x-ray generation and measurements
« Reply #15 on: March 03, 2017, 15:42:38 pm »
this is strange... because it should not generate xray on such small gap... the collisions with air molecules would not allow the electrons to impact with enough energy at the target...

is your geiger counter based on a ionization tube? or is a electronic sensor?

the mean free path at ambient pressure is too small to electrons to gain enough energy...

i´m afraid you are picking up electromagnetic noise at your counter... or i could be totally wrong

i see all the electronics of your counter exposed... thats why i´m thinking about this...

my pll circuit when not shield properly also picks strange behavior...

« Last Edit: March 03, 2017, 16:03:27 pm by sebosfato »