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The Last Word


Bazza

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Re: The Last Word

 

Re: Politicians -- our government (a liberal-conservative coalition) came to power by a number of promises. They have fulfilled most of those promises -- and are therefore being burned in the polls.

 

It's not easy, being an honest politician. :)

It's not, because then all the crooks jump all over you to find SOMETHING.

 

Inexperience, usually.

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Re: The Last Word

 

It's not, because then all the crooks jump all over you to find SOMETHING.

 

Inexperience, usually.

Yars, the Social Democrats have been in power since the end of WWII, with only three times in opposition (this time being the third). So the other parties hasn't had that much actual practice in running a country -- and then getting re-elected.
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Re: The Last Word

 

. . . Well, our politicians aren't always straight with the electorate, but I have the feeling that what they say they want accomplished, they actually try to accomplish. Then there is, of course, the matter of priorities and horse trade to get things actually done . . . And the occasional raising of their own salaries.

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Re: The Last Word

 

Rep Power: 6160

Na I 6160.753A is one of a very small number of neutral sodium lines that can be used for deriving an abundance of this element in solar-type and cooler stars. The D lines (5889, 5895 A) are immensely strong (they are the spectral lines that give flames in nearly all sources their strong orange color), meaning that most of the abundance information in the spectral line is submerged in favor of line-damping processes that tell you more about the thermal structure of the stellar atmosphere rather than the abundance of sodium. So the weak lines at 6154 and 6160 A are among the better choices remaining, although the former has a weak but annoying Cr I line blending with it that compromises its utility somewhat.

 

The abundance of sodium, it is found, turns out to vary in the red giants of globular clusters much like the CNO nuclides do, with some stars having elevated sodium and nitrogen abundances and lowered oxygen abundances relative to most of the others. It is well known (Hans Bethe won the Nobel Prize in physics for realizing this) that oxygen participates in the CNO cycle, which results in it being converted to nitrogen. Standard stellar structure models don't predict the mixing of such fully CNO-cycled material to the stellar surface, but it seems to happen in some stars. That sodium participates also was something of a surprise, and the only reaction cycle that works is with the isotopes of neon being cycled to sodium, which again is not predicted to be mixed to the surface of globular cluster giants, but it clearly must happen. Details of the mixing process are hard to work out, given that it's hydrodynamics in a nasty, turbulent regime.

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Re: The Last Word

 

You have one of those for every possible rep power' date=' don't you?[/quote']

 

No. When one hits an interesting spectral line ... and for me, those are going to be between 4000 and about 8800, plus a couple of stray outliers ... I'll succumb to temptation and wax didactic.

 

This one, about the sodium line, was a happy coincidence, because (1) there really are only 4 good sodium lines, and this one is by far the best, (2) the sodium stuff in globular clusters is a little odd, and (3) because last spring I got to referee a paper bearing on the problem.

 

EDIT: Once we get to 5- and 6-digit numbers an entirely new set of associations, with HD numbers. But that's a long way off.

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