[time-nuts] Hyperfine splittings

Magnus Danielson cfmd at bredband.net
Sun Nov 26 01:33:23 UTC 2006


From: Magnus Danielson <cfmd at bredband.net>
Subject: Re: [time-nuts] Hyperfine splittings
Date: Wed, 08 Nov 2006 09:35:09 +0100 (CET)
Message-ID: <20061108.093509.-1300535164.cfmd at bredband.net>

Dear fellow time-nuts,

I have now upgraded my list of hyperfine splittings at

http://rubidium.dyndns.org/~magnus/physics/hyperfine/

There is a number of improvements. For Hydrogen I maintain a few multiples, but
is considering just adding the reference list up with those details and
maintain the best estimate that I know of. Also lacking a bunch of references,
even if I have them lying around. Well, it is work in progress.

> > I have 1 420 405 751.768 ± 0.002 Hz for
> > hydrogen at my "hyperfine" page:
> > 
> > http://www.leapsecond.com/pages/unix/
> 
> Yes, but do you have a reference for that one? Preferably an open source.

This appears to be the older estimate from 
H. Hellwig, R.C. Vessot, M.W. Levine, P.W. Zitzewitz, D.W. Allan and D.J. Glaze
"Measurement of the Unperturbed Hydrogen Hyperfine Transition Frequency"
IEEE T. Instrum. Meas. 19 p200-209
http://www.tf.nist.gov/timefreq/general/pdf/13.pdf

A good read on a rainy day if you want to learn on how you remove wall shift
errors from your estimate.

Anyway, Jacques Vanier and Claude Audoin presents the value of
1 420 405 751.770 +/- 0.003 Hz as a result of 12 different papers ranging from
1963 to 1980. However, they do not include the above paper.

Cheers,
Magnus




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