Description of the individual files:

• light_shifts.csv (text/csv) - Lattice light shift estimates for different conditions

  
  

  This file summarizes the light shift estimates shown in Figure 1 of Dörscher et al. (2023).
  These are estimates of the frequency shift of the 429 THz clock transition in neutral strontium caused by the optical lattice potential via the ac-Stark effect.
  They have been computed for different experimental conditions, light shift models, and values of the E2-M1 differential polarizability, see Dörscher et al. (2023) for further details.

  
  
  
  
  • Column 1 - Specifies which value is used for the E2-M1 differential polarizability. Either of:
    
    
    • Ushijima et al. - Ushijima et al. (2018)
    
    
    • Porsev et al. - Porsev et al. (2018)
    
    
    
    
  
  
  • Column 2 - Specifies with light shift model is used. Either of:
    
    
    • Brown et al. - Model from Brown et al. (2017) with additional input from Beloy et al. (2020) - as described and used in Dörscher et al. (2023)
    
    
    • Ushijima et al. - Model from Ushijima et al. (2018) with the correction from Beloy et al. (2020)
    
    
    
    
  
  
  • Column 3 - Specifies which population distribution is used. Either of "hot" or "cold", see Dörscher et al. (2023) for details.
  
  
  • Column 4 - Estimated light shift (in units of the transition frequency)
  
  

  • Column 5 - Standard uncertainty of the estimate (in units of the transition frequency)

    
    

    Columns are separated by semicolons.
    The file contains one header line (labels).

    
    
  
  
  
  



• measurement_e2m1.dat (text/csv) - Measurement results for the differential light shift between hot & cold atoms

  
  

  This file contains the light shift differences measured between 'cold' and 'hot' atomic samples, as described in Dörscher et al. (2023).
  The data set is a series of instantaneous frequency differences of the interleaved stabilization loops (hot - cold).
  Each line corresponds to one iteration of both loops, with a period of about 13.9 s.
  Frequency values are given in units of the transition frequency.
  Any interruptions have been removed from the data set.

  
  

  The total Allan deviation shown in Fig. 2 of Dörscher et al. (2023) has been computed from this data set.

  
  



• measurement_ref.dat (text/csv) - Measurement results for the differential light shift between deep & shallow lattices

  
  

  This file contains the light shift differences measured between a deep and a shallow trap, as described in Dörscher et al. (2023).
  The data set is a series of instantaneous frequency differences of the interleaved stabilization loops (deep - shallow).
  Each line corresponds to one iteration of both loops, with a period of about 13.9 s.
  Frequency values are given in units of the transition frequency.
  Any interruptions have been removed from the data set.

  
  



• sideband_cold.dat (text/csv) - Measurement of the sideband spectrum of 'cold' atoms

  
  

  This file contains a measurement of the sideband spectrum on the clock transition using 'cold' atoms as described in Dörscher et al. (2023).

  
  
  
  
  • Column 1 - Frequency offset (in Hz) of the interrogation laser, given with respect to the carrier
  
  

  • Column 2 - Population fraction in the excited state, measured by balanced fluorescence detection

    
    

    Columns are separated by semicolons.
    The file contains two header lines (labels & units).

    
    
  
  
  
  



• sideband_hot.dat (text/csv) - Measurement of the sideband spectrum of 'hot' atoms

  
  

  This file contains a measurement of the sideband spectrum on the clock transition using 'hot' atoms as described in Dörscher et al. (2023).

  
  
  
  
  • Column 1 - Frequency offset (in Hz) of the interrogation laser, given with respect to the carrier
  
  

  • Column 2 - Population fraction in the excited state, measured by balanced fluorescence detection

    
    

    Columns are separated by semicolons.
    The file contains two header lines (labels & units).