====== Notes/Informations ======

===== Frequency-Comb Hannover =====

^ Channel  ^ Measured                            ^ Frequency     ^ Sign  ^ Interval (axis)  ^ Max outliers (Alarmschwelle)      ^ F(x)     ^
| CH1      | IQ-Resonator (R1) vs. Comb          | 29.347 MHz    | -     | ± 900 Hz         | 500 Hz                            | -fx      |
| CH2      | CEO                                 | 20 MHz        | -     | ± 0.24 Hz        | 0.15 Hz                           | -fceo    |
| CH3      | Reprate/16                          | 6.250001 MHz  |       | ± 0.0018 Hz      | 0.001 Hz                          | frep/16  |
| CH4      | Link vs. Comb                       | 22.432 MHz    | -     | ± 900 Hz         | 500 Hz                            | -fy      |
| CH5      | Virtualer Beat (Link vs. IQ-Laser)  | 21,27173 MHz  |       | ± 18 Hz          | 10 Hz                             | fv       |
| CH6      | Manypoint-AOM                       | 36 MHz        |       | ±18 Hz           | 10 Hz                             |          |
| CH7      | Stell-AOM vom IQ-Laser              | 35.0X MHz     |       | ± 4000 Hz        | 2000 Hz (+ correction of Offset)  | f_Stell  |
| CH8      | Rubidiumuhr referenziert auf GPS    | 10 MHz        |       | ± 0.0018 Hz      | 0.001 Hz                          |          |

  * Modenverhältnis: Ratio: N=n916/nLink = 3275292/1944000 = 1.684820987654321… 
  * Repetitionsrate: 100,0000226 MHz

{{:groups:mg:virtuelle_schwebung.png?600|}} {{:groups:mg:optische_frequenzverschiebungen.jpg?400|}}

  * AOM (+77.111 MHz) used for atom-lock + fiber stabilization(5m)
  * AOM (+80.111 MHz) used for fiber stabilization(30m)
  * Double-pass AOM (-2*102,XX MHZ) used for spectroscopy (frequency shift), feedback-loop!!!
  * Channel 7 = 138 MHz (Synthesizer, referenced by 10 MHz GPS) - Double-pass AOM

  * Atom frequency: nu_opt(Mg = ( 3275292*col(e)*16 - 2*col(d) - col(c) + 80,111e6)*2 + 77,111e6
  * Laserfrequency: f_laser = 3275292*frep*16 - 2*fceo - fx
  * Resonator 1 frequency: f_R1 = 3275292*frep*16 - 2*fceo - fx + (-2*f_AOM_R1)
  * Double-pass AOM: f_AOM_R1 = 138 MHz - f_Stell

==== Virtual-Beat ====

  * fv = (fy + fceo) - ( (fx + 2*fceo) / (3275292/1944000) ) + (2*10 MHz)


==== Evaluation (PTB) ====
  * fx= col(c)  (#1, negatives fx)
  * fceo=col(d) (#2) (negatives fceo)
  * frep=col(e) (#3, frep/16)

=== Test analysis ===
  * nu_opt(Mg) - nu_(Mg2015)[Hz] = nu_opt(Mg) - 655058646691000


-> nu_opt(Mg) - nu_(Mg2015)[Hz] = ( f_laser + 80,111e6)*2 + 77,111e6 - 655058646691000\\


===== Frequency-Comb Braunschweig =====




====== Clocks hight in respect to the geoid ======

In front of the university are studs which are used as a reference. In the PDF everything is explained and is given by Dr. Heiner Denker (Institut für Erdvermessung (IFE)), he will also estimate the experiments height with higher precision soon.
{{ :groups:mg:img_0138.jpg?nolink&200|}}
{{ :groups:mg:afisbuchnachweis362400016.pdf |}}