Orion-KL on 22GHz
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Michiel Klaassen
Jan 24, 2023, 8:01:54 AM1/24/23
to sara-list, camras-forum
On 8, 15 and 21 of august 2022 we mesaured the Orion-KL 22GHz maser. Because we have a DRO based local oscillator, the frequency stability is bad. With a thermostat we tried to stabilize that as much as possible.
Still we had to shift the 5 minute integration results to align one another. After that 3 day's result also had to be shifted a few bins to align. We used the python correlation function for that.
The method is correlate two graphs, shift 1 bin, correlate again etc. Could also be done by eye, but correlating is more secure.
When all are aligned, then the amplitude has to be corrected also. This is done by amplifying and subtracting two graphs from each other; amplify a little, subtract, etc.
The minimum result gives the best equality.
Now the 3 plots are averaged.
Next the end plot is analysed with the triple water maser gaussian. A best fit curve is made. The triple profile form is a measure for the temperature.
Excluding the beaming peak, the other peaks could be constructed of around 100K gaussians. These temperatures are also mentioned in astronomical papers.
Here it is stated that a single component is rarely dominant. So a single gaussian is not likely, but we can see that a triple gaussian is difficult to fit; the residuals are not low. Perhaps a dual gaussian would be reasonable.
Data capturing and postprocessing was done with NOOELEC SDR, CFRAD2.exe and Python plot.
See also the 22GHz maser tab.
Michiel
parac.eu
Still we had to shift the 5 minute integration results to align one another. After that 3 day's result also had to be shifted a few bins to align. We used the python correlation function for that.
The method is correlate two graphs, shift 1 bin, correlate again etc. Could also be done by eye, but correlating is more secure.
When all are aligned, then the amplitude has to be corrected also. This is done by amplifying and subtracting two graphs from each other; amplify a little, subtract, etc.
The minimum result gives the best equality.
Now the 3 plots are averaged.
Next the end plot is analysed with the triple water maser gaussian. A best fit curve is made. The triple profile form is a measure for the temperature.
Excluding the beaming peak, the other peaks could be constructed of around 100K gaussians. These temperatures are also mentioned in astronomical papers.
Here it is stated that a single component is rarely dominant. So a single gaussian is not likely, but we can see that a triple gaussian is difficult to fit; the residuals are not low. Perhaps a dual gaussian would be reasonable.
Data capturing and postprocessing was done with NOOELEC SDR, CFRAD2.exe and Python plot.
See also the 22GHz maser tab.
Michiel
parac.eu
Michiel Klaassen
Jan 25, 2023, 11:01:30 AM1/25/23
to sara-list, camras-forum
I added some more text and plots and a speculation part onto the Orion-KL webpage.
https://www.parac.eu/projectmk27-Orion-KL.htm
+++++++++++++++++++++++++++++++++++++++++++
The Vlsr of Orion-Kl is 7.5km/s.
And now the speculative part.
If we take the star as reference to be 0 km/s, then we can calculate the peaks to be at velocities relative to the centre proto sun.
The clouds (e and f) close to the reference are the clouds moving slowly around the star, and in a Kepler solar system, these are the most distant rings.
The clouds with the highest velocities (a,b,i,j) circle close to the protostar.
Interesting and logical is also that the temperature of the close by clouds i and j are higher (140K) than the clouds f and e (110K and 80K) far away from the protosun.
As a comparison, the clouds b and j move at about 11km/s and that is in our solar system the speed of Saturn around the sun.
Peak b could be caused by a maser path passing through a warping rim of other rings.
Or it could be a Jupiter like gas orb sweeping up material between the rings, acting as a short for the maser light between the rings.
+++++++++++++++++++++++++++++++++++++++++++++++
Still have to do some writing up for Cep-A, Mon-R2, W44 and W51.
I thought I finished W49N, W3 and W75, but now knowing the triple water maser profile, I have to edit those also.
(yes,and spelling check)
Michiel
https://www.parac.eu/projectmk27-Orion-KL.htm
+++++++++++++++++++++++++++++++++++++++++++
The Vlsr of Orion-Kl is 7.5km/s.
And now the speculative part.
If we take the star as reference to be 0 km/s, then we can calculate the peaks to be at velocities relative to the centre proto sun.
The clouds (e and f) close to the reference are the clouds moving slowly around the star, and in a Kepler solar system, these are the most distant rings.
The clouds with the highest velocities (a,b,i,j) circle close to the protostar.
Interesting and logical is also that the temperature of the close by clouds i and j are higher (140K) than the clouds f and e (110K and 80K) far away from the protosun.
As a comparison, the clouds b and j move at about 11km/s and that is in our solar system the speed of Saturn around the sun.
Peak b could be caused by a maser path passing through a warping rim of other rings.
Or it could be a Jupiter like gas orb sweeping up material between the rings, acting as a short for the maser light between the rings.
+++++++++++++++++++++++++++++++++++++++++++++++
Still have to do some writing up for Cep-A, Mon-R2, W44 and W51.
I thought I finished W49N, W3 and W75, but now knowing the triple water maser profile, I have to edit those also.
(yes,and spelling check)
Michiel
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