¿ªÔÆÌåÓý

ctrl + shift + ? for shortcuts
© 2025 Groups.io
  1. XRF
  2. Topics

Testing valididty of Niobium Ka peaks in radioactive rocks.

 

Equipment used-
Amptek CdTe low energy X-Ray sensor with Amptek PX4 power supply/ MCA unit.
The sensor/preamplifier head plus sampleare inside a Pb-Cd-Cu graded shield with a total of 1" thickness.

First a10 minute precision calibration scan was made by using Am-241 to? excite XRF characteristic X-Rays from a pure Nb metal sample. (Scan No.1)

Immediately following calibration as Gamma Scan was taken of a radioactive rock we have been calling "Columbite" in these early tests. (Scan No.2)

Next we overlaid both together at once in Amptek's ADMCA program, with the green outline of the calibration peak going slightly taller. Filled-in red peaks are the gamma scan. Peaks around 16.5 are abundant from the higher daughters of Uranium decay, ranging from Ac @15.71 keV to Pa @ 16.70 keV

An NaI(Tl) probe would have difficulty separating them. Switching to Kb XRF @ 18.62 might be a little better but not with NaI(Tl).
It took a full 4096 channels to view this sufficiently closely with enough exactness to make a determination, however going to 8k channels made calibration harder to do and was abandoned.Likewise extensive tests with 1k and then 2k channels quickly showed peaks to be insufficiently spaced out to make a determination.

CdTe_study_of_possible_Nb_Ka_X-Rays_in_ore.png

.

No.1-Nb-Peak_Study-XRF-Am_X8-Pure-Nb-Metal-PreciseRe--Calibration-10min-4kChan.mca
No.1-Nb-Peak_Study-XRF-Am_X8-Pure-Nb-Metal-PreciseRe--Calibration-10min-4kChan.mca
No.2-Nb-Peak_Study-Gamma-Spec--Columbite-PreciseRe--Calibration-10min-4kChan.mca
No.2-Nb-Peak_Study-Gamma-Spec--Columbite-PreciseRe--Calibration-10min-4kChan.mca
CdTe_study_of_possible_Nb_Ka_X-Rays_in_ore.png

 

It looks to me like your CdTe has enough resolution to say for sure that this does not have Nb.

Charles


On Thu, Dec 26, 2019 at 6:12 PM <GEOelectronics@...> wrote:
Equipment used-
Amptek CdTe low energy X-Ray sensor with Amptek PX4 power supply/ MCA unit.
The sensor/preamplifier head plus sampleare inside a Pb-Cd-Cu graded shield with a total of 1" thickness.

First a10 minute precision calibration scan was made by using Am-241 to? excite XRF characteristic X-Rays from a pure Nb metal sample. (Scan No.1)

Immediately following calibration as Gamma Scan was taken of a radioactive rock we have been calling "Columbite" in these early tests. (Scan No.2)

Next we overlaid both together at once in Amptek's ADMCA program, with the green outline of the calibration peak going slightly taller. Filled-in red peaks are the gamma scan. Peaks around 16.5 are abundant from the higher daughters of Uranium decay, ranging from Ac @15.71 keV to Pa @ 16.70 keV

An NaI(Tl) probe would have difficulty separating them. Switching to Kb XRF @ 18.62 might be a little better but not with NaI(Tl).
It took a full 4096 channels to view this sufficiently closely with enough exactness to make a determination, however going to 8k channels made calibration harder to do and was abandoned.Likewise extensive tests with 1k and then 2k channels quickly showed peaks to be insufficiently spaced out to make a determination.

CdTe_study_of_possible_Nb_Ka_X-Rays_in_ore.png

.

ThereminoMCA_Amptek_DppMCA_Geo_columbite.png

 

¿ªÔÆÌåÓý

Looks to me you haven¡¯t counted long enough to say anything. This peak isn¡¯t even 25 counts.

Dud

?

From: [email protected] [mailto:[email protected]] On Behalf Of Charles David Young
Sent: Thursday, December 26, 2019 5:41 PM
To: [email protected]
Subject: Re: [XRF] Testing valididty of Niobium Ka peaks in radioactive rocks.

?

It looks to me like your CdTe has enough resolution to say for sure that this does not have Nb.

?

Charles

?

On Thu, Dec 26, 2019 at 6:12 PM <GEOelectronics@...> wrote:

Equipment used-
Amptek CdTe low energy X-Ray sensor with Amptek PX4 power supply/ MCA unit.
The sensor/preamplifier head plus sampleare inside a Pb-Cd-Cu graded shield with a total of 1" thickness.

First a10 minute precision calibration scan was made by using Am-241 to? excite XRF characteristic X-Rays from a pure Nb metal sample. (Scan No.1)

Immediately following calibration as Gamma Scan was taken of a radioactive rock we have been calling "Columbite" in these early tests. (Scan No.2)

Next we overlaid both together at once in Amptek's ADMCA program, with the green outline of the calibration peak going slightly taller. Filled-in red peaks are the gamma scan. Peaks around 16.5 are abundant from the higher daughters of Uranium decay, ranging from Ac @15.71 keV to Pa @ 16.70 keV

An NaI(Tl) probe would have difficulty separating them. Switching to Kb XRF @ 18.62 might be a little better but not with NaI(Tl).
It took a full 4096 channels to view this sufficiently closely with enough exactness to make a determination, however going to 8k channels made calibration harder to do and was abandoned.Likewise extensive tests with 1k and then 2k channels quickly showed peaks to be insufficiently spaced out to make a determination.

CdTe_study_of_possible_Nb_Ka_X-Rays_in_ore.png

.

 

That's a beautiful rendition Charles, I love it. Maybe some day I can do that conversion too.

Charles, it's not so much does it have Nb, it's can we use the natural radiation to prove it has Nb..... This is just a bad spot in the spectrum to be looking for weak Nb peaks when the natural radiation is literally filling the area with peaks. Lanthanide series Ka will no doubt fare much better. The picture is of Uranium Sulfate (no lower daughters) done on my Si-PIN detector - the blue tinted area is centered on poor little niobium's 16.61 peak compared to the massive Thorium etc. peak centered on 16.20.

If this were an AM radio dial instead of a gamma spectrum, radio station WNb at 1661 KHz would never be heard over the mighty clear-channel station WTh at 1620 KHz. His two choices would be to increase his power by 20dB or move up the dial to a less busy channel.


-30- 10-4 73 et SK (radio talk)
Geo

Uranium_Upper_Daughters-VS-Niobium.png

 

Just off hand, judging from No. 2 it looks like your "Columbite" does not auto fluoresce Ni.

That is, the 16.61 photopeak is missing.
However,the photopeak from the pure Nb at approx 16.4 does correlate with your "columbite" auto fluorescence.

Randall

PS How do I open .mca files? Sorry, I guess I missed that.

----- Original Message -----
From: GEOelectronics@...
To: [email protected]
Sent: Thu, 26 Dec 2019 17:12:20 -0800 (PST)
Subject: [XRF] Testing valididty of Niobium Ka peaks in radioactive rocks.

Equipment used-
Amptek CdTe low energy X-Ray sensor with Amptek PX4 power supply/ MCA unit.
The sensor/preamplifier head plus sample are inside a Pb-Cd-Cu graded shield with a total of 1" thickness.

First a10 minute precision calibration scan was made by using Am-241 to? excite XRF characteristic X-Rays from a pure Nb metal sample. (Scan No.1)

Immediately following calibration as Gamma Scan was taken of a radioactive rock we have been calling "Columbite" in these early tests. (Scan No.2)

Next we overlaid both together at once in Amptek's ADMCA program, with the green outline of the calibration peak going slightly taller. Filled-in red peaks are the gamma scan. Peaks around 16.5 are abundant from the higher daughters of Uranium decay, ranging from Ac @15.71 keV to Pa @ 16.70 keV

An NaI(Tl) probe would have difficulty separating them. Switching to Kb XRF @ 18.62 might be a little better but not with NaI(Tl).
It took a full 4096 channels to view this sufficiently closely with enough exactness to make a determination, however going to 8k channels made calibration harder to do and was abandoned.Likewise extensive tests with 1k and then 2k channels quickly showed peaks to be insufficiently spaced out to make a determination.

.
 

DPPMCA from here:


On Fri, Dec 27, 2019 at 11:43 AM Randall Buck <rbuck@...> wrote:


Just off hand, judging from No. 2 it looks like your "Columbite" does not auto fluoresce Ni.

That is, the 16.61 photopeak is missing.
However,the photopeak from the pure Nb at approx 16.4 does correlate with your "columbite" auto fluorescence.

Randall

PS? How do I open .mca files?? ?Sorry, I guess I missed that.




----- Original Message -----
From: GEOelectronics@...
To: [email protected]
Sent: Thu, 26 Dec 2019 17:12:20 -0800 (PST)
Subject: [XRF] Testing valididty of Niobium Ka peaks in radioactive rocks.

Equipment used-
Amptek CdTe low energy X-Ray sensor with Amptek PX4 power supply/ MCA unit.
The sensor/preamplifier head plus sample are inside a Pb-Cd-Cu graded shield with a total of 1" thickness.

First a10 minute precision calibration scan was made by using Am-241 to? excite XRF characteristic X-Rays from a pure Nb metal sample. (Scan No.1)

Immediately following calibration as Gamma Scan was taken of a radioactive rock we have been calling "Columbite" in these early tests. (Scan No.2)

Next we overlaid both together at once in Amptek's ADMCA program, with the green outline of the calibration peak going slightly taller. Filled-in red peaks are the gamma scan. Peaks around 16.5 are abundant from the higher daughters of Uranium decay, ranging from Ac @15.71 keV to Pa @ 16.70 keV

An NaI(Tl) probe would have difficulty separating them. Switching to Kb XRF @ 18.62 might be a little better but not with NaI(Tl).
It took a full 4096 channels to view this sufficiently closely with enough exactness to make a determination, however going to 8k channels made calibration harder to do and was abandoned.Likewise extensive tests with 1k and then 2k channels quickly showed peaks to be insufficiently spaced out to make a determination.

.
 

Randall, you can open the files with Amptek DPPMCA or the same ADMCA that I made them with. Both free on Amptek site or my site we linked earlier.

George

----- Original Message -----
From: Randall Buck <rbuck@...>
To: [email protected]
Cc: [email protected]
Sent: Fri, 27 Dec 2019 13:42:56 -0500 (EST)
Subject: Re: [XRF] Testing valididty of Niobium Ka peaks in radioactive rocks.



Just off hand, judging from No. 2 it looks like your "Columbite" does not auto fluoresce Ni.

That is, the 16.61 photopeak is missing.
However,the photopeak from the pure Nb at approx 16.4 does correlate with your "columbite" auto fluorescence.

Randall

PS How do I open .mca files? Sorry, I guess I missed that.




----- Original Message -----
From: GEOelectronics@...
To: [email protected]
Sent: Thu, 26 Dec 2019 17:12:20 -0800 (PST)
Subject: [XRF] Testing valididty of Niobium Ka peaks in radioactive rocks.

Equipment used-
Amptek CdTe low energy X-Ray sensor with Amptek PX4 power supply/ MCA unit.
The sensor/preamplifier head plus sample are inside a Pb-Cd-Cu graded shield with a total of 1" thickness.

First a10 minute precision calibration scan was made by using Am-241 to? excite XRF characteristic X-Rays from a pure Nb metal sample. (Scan No.1)

Immediately following calibration as Gamma Scan was taken of a radioactive rock we have been calling "Columbite" in these early tests. (Scan No.2)

Next we overlaid both together at once in Amptek's ADMCA program, with the green outline of the calibration peak going slightly taller. Filled-in red peaks are the gamma scan. Peaks around 16.5 are abundant from the higher daughters of Uranium decay, ranging from Ac @15.71 keV to Pa @ 16.70 keV

An NaI(Tl) probe would have difficulty separating them. Switching to Kb XRF @ 18.62 might be a little better but not with NaI(Tl).
It took a full 4096 channels to view this sufficiently closely with enough exactness to make a determination, however going to 8k channels made calibration harder to do and was abandoned.Likewise extensive tests with 1k and then 2k channels quickly showed peaks to be insufficiently spaced out to make a determination.

.

1 - 7 of 7