On Tue, Nov 21, 2017 at 2:50 PM, Attila Kinali <att...@kinali.ch> wrote:
> [...] The advantage of the platinum valve > system is that it "generates" single atom Hydrogen, as required > by the maser. Picking nits here.. It was my understanding that the splitting of molecular hydrogen into atomic hydrogen happens using RF in the dissociator - not in the platinum leak valve. Is my understanding incorrect? > Within the cavity there is a small glass bulb that keeps the atoms > in the right position of the cavity field. 4.5 liters in EFOS type masers - so not *that* small. I believe other masers are the same order of magnitude. > Yes, IIRC normal numbers are several 10s to 100s of wall collisions > before the atom loses its state due to wall colisions and without > contributing to the signal. > Lifetime ~1 second I think > > I've long wondered what causes the slow frequency drift, typically > amounting > > to about 3E-14 over a time span of several months. > > Mostly changes in the wall coating leading to a different wall collision > shift and mechanical changes of the cavity dimension (think air pressure > and creep) leading to a different cavity pulling. To a lesser extend > it's the changes in the quality of the vacuum and number of Hydrogen atoms > in the cavity. Also aging of electronic components - coarse tuning of the cavity is done by temperature, and any drift if the temperature-sensor/amplifiers etc will result in drift. At least for EFOS type masers. Ole _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.