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Additional data for the publication "Transportable strontium lattice clock with 4 x 10^-19 blackbody radiation shift uncertainty"
No full textWe describe a transportable optical lattice clock based on the 1S0 -> 3P0 transition of lattice-trapped 87Sr atoms with a total systematic uncertainty of 2.1 x 10^-18. The blackbody radiation shift, which is the leading systematic effect in many strontium lattice clocks, is controlled at the level of 4.0 x 10^-19, as the atoms are interrogated inside a well-characterised, cold thermal shield. Using a transportable clock laser, the clock reaches a frequency instability of about 5 x 10^-16 (tau/s)^-0.5, which enables fast reevaluations of systematic effects. By comparing this clock to the primary caesium fountain clocks CSF1 and CSF2 at Physikalisch-Technische Bundesanstalt, we measure the clock transition frequency with a fractional uncertainty of 1.9 x 10^-16, in agreement with previous results. The clock was successfully transported and operated at different locations. It holds the potential to be used for geodetic measurements with centimetre-level or better height resolution and for accurate inter-institute frequency comparisons.**Figure_2a.tsv**: Data shown in figure 2 (a) of the manuscript. State populations are measured as described in the manuscript.
Columns 1-2 (3-4) contain the frequency offset of the clock laser from a centre frequency that is arbitray but close to resonance and the fraction of atoms detected in the 3P0 state after interrogation where atoms are initially prepared in the magnetic substate m_F = -9/2 (+9/2) of the 3P0 state.
format: "text/tsv"
recommended software: [Python](https://www.python.org/)
**Figure_2b.tsv**: Source data of the Allan deviation shown in figure 2 (b) of the manuscript.
Deviation of the fractional frequency difference between the transportable clock Sr4 and the stationary clock Sr3 from its mean value, on a one-second grid.
Optical beat frequency between clock lasers recorded by dead-time-free counters.
Timestamps and gaps removed.
format: "text/tsv"
recommended software: [Python](https://www.python.org/)
**Figure_4.tsv**: Data shown in figures 4 (a) and (b) of the manuscript.
Fractional frequency differences between atoms moved by a variable distance and atoms at the centre of the BBR shield, with the difference in second-order Zeeman shift removed as described in the manuscript.
Columns 1-4 contain the moving distance, the measured fractional frequency difference, the deviation thereof from the expected differential BBR shift, and the measurement uncertainty.
format: "text/tsv"
recommended software: [Python](https://www.python.org/)
**Figure_B1.tsv**: Data shown in figure B1 of the manuscript.
Radii of the holes 1 and 2 of the BBR shield as measured at the outer edges for different angles of orientation, before and after coating and assembly of the parts.
Measured with a measuring microscope.
Corrected for an offset measured with a coordinate measuring machine, as described in the manuscript.
Colummn 1 contains the angle of orientation, columns 2-5 the measured radii of the holes as stated in the header.
format: "text/tsv"
recommended software: [Python](https://www.python.org/)
**Figure_E1.tsv**: Data shown in figure E1 of the manuscript.
Allan deviation values of the frequency ratio between the hydrogen maser used in the absolute frequency measurements and either the transportable clock (Sr4) or the stationary clock (Sr3).
Columns 1-5 contain the averaging times and Allan deviation values of the measurements in the order shown in figure E1, as also stated by the column headers.
Computed from experimental data
format: "text/tsv"
recommended software: [Python](https://www.python.org/)We acknowledge support by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany\u27s Excellence Strategy -- EXC-2123 QuantumFrontiers -- Project-ID 3908379.67.
We acknowledge support by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under SFB 1464 TerraQ -- Project-ID 434617780 -- within projects A04 and A05.
This work was partially supported by the Max Planck-RIKEN-PTB Center for Time, Constants and Fundamental Symmetries.
This work has received funding from the European Partnership on Metrology, co-financed by the European Union\u27s Horizon Europe Research and Innovation Programme and by the Participating States, under grant number 22IEM01 TOCK
FEM analysis of thermal properties of an optical gas cell for ro-vibrational spectroscopic thermometry
No full textWe utilised Finite Element Method (FEM) to analyse the thermal behaviour of newly designed optical gas cell. we have investigated the impact of the gas pressure, design of the optical windows, thermal radiation and the flow regime inside the heat exchanger on the temperature gradient in the spectroscopic gas cells. Considering practical spectroscopic measurement conditions, the simulation covered wide ranges of pressure and temperature, from 1 mbar to 1000 mbar, and from 200 K to 400 K, respectively. The results of the FEM analysis highlight the significance of the design of optical windows, including the size and isolation, in maintaining gas thermodynamic stability and homogeneity. Moreover, the simulation demonstrates how temperature profiles vary in different conditions and how viscous dissipation in the heat exchanger fluid affects the gas temperature uniformity. Furthermore, the study emphasises the importance of the place where the temperature sensor is installed, for accurate temperature measurement. The findings of this research aim to provide valuable insights for the future design of optical gas cells
Liste der bei der PTB zugelassenen Blockiersysteme für Erbwaffen gemäß § 20 Waffengesetz (WaffG)
No full textListe der bei der PTB zugelassenen Blockiersysteme für Erbwaffen gemäß § 20 Waffengesetz (WaffG
Flow Cytometry Pulse Shape Data and their derived quantities
No full textThese files contain the measured pulse data used in the paper. Originally the data was saved in tdms and fcs files, but was converted to hdf5 and csv files for better accessibility. Channel names are forward scattering (fsc) and side scattering (ssc). The h5 file was then postprocessed and the resulting quantities saved in a csv file.Folder raw data:
PS1540nm.h5:
research object: polystyrene particles (PS)
method: Flow Cytometer
format: h5
recommended software: python nptdms package
parameters: size 1540nm, laserwavelength 488nm, monodisperse
PS 1mu+5mu 1.03microl_per_second.h5:
research object: polystyrene particles
method: Flow Cytometer
format: h5
recommended software: python nptdms package
parameters: 1 µm and 5 µm mixed, 1000 µL of 5 µm PS + 1 µm 1:1000 diluted 1µm PS, laserwavelength 488nm, flowrate 1.03µL/s
PS 1mu+5mu 0.443microl_per_second.h5:
research object: polystyrene particles
method: Flow Cytometer
format: h5
recommended software: python nptdms package
parameters: 1 µm and 5 µm mixed, 1000 µL of 5 µm PS + 1 µm 1:1000 diluted 1µm PS, laserwavelength 488nm, flowrate 0.443µL/s
PS 1mu+5mu 0.177microl_per_second.h5:
research object: polystyrene particles
method: Flow Cytometer
format: h5
recommended software: python nptdms package
parameters: 1 µm and 5 µm mixed, 1000 µL 5 µm PS + 1 µm 1:1000 diluted 1µm PS, laserwavelength 488nm, flowrate 0.177µL/s
Folder postprocessed data:
the data in "raw data" postprocessed regarding describing quantities. See table headers for names
Liste der von der PTB zugelassenen Schusswaffen gemäß § 8 Beschussgesetz (BeschG)
No full textListe der von der PTB zugelassenen Schusswaffen gemäß § 8 Beschussgesetz (BeschG
D5: Document describing two radioactive reference materials, developed and shipped to participants for their radioactive content characterisation
No full textIn order to have comparable data in time and space, the aim of the work package 3 of the MetroPOEM project is to produce two candidate reference materials, comprising common radioactive pollutants found in environmental samples (241Am, 237Np, 239Pu, 240Pu, 234U, 235U, 236U and 238U). Two matrices were chosen, one liquid and one solid. These materials will be used in an interlaboratory comparison, where partners will use radiometric and/or mass spectrometry measurements to determine the concentrations and isotopic ratios of
the radionuclides.
The synthesis of the candidate reference materials will be described in a publication in 2025. Indeed, this work was selected for an oral communication at the ICRM 2025 conference in May 2025 and the authors plan to submit a paper associated with the talk. The paper must be submitted by 18th April 2025.
The first part of gives the general strategy for the development of the two reference materials (RM): the method of spiking, the number of samples chosen for homogeneity and stability studies, the total amount of materials to produce and the sampling plan. The next two parts describe in more details the preparation and characterisation of the two reference materials.Das Projekt MetroPOEM (21GRD09 MetroPOEM) wird finanziert aus dem Forschungsprogramm „Europäische Partnerschaft für Metrologie“ der Europäischen Union, kofinanziert von den Mitgliedsstaaten
Liste der von der PTB zugelassenen Schusswaffen gemäß § 8 Beschussgesetz (BeschG)
No full textListe der von der PTB zugelassenen Schusswaffen gemäß § 8 Beschussgesetz (BeschG
Measurement Data for "Parallelization of the optical pulse-drive for AC Josephson voltage standards"
No full textCharacterization measurements of PTB\u27s optical JAWS.The archive contains 12 data files corresponding to the graphs shown in the publication. The data elaboration and graphs creation were performed with the software tool “Origin” and the data tables have been subsequently exported in a tabular format.
- Filename: fig3a.txt
Parent Figure 3a of main text.
Data description: Processed data for the plot (1st line: Physical quantity, 2nd line: Physical unit, remaining lines: Numerical Data)
RMS ampltiude spectrum of the positiv half-sine wave.
- Filename: fig3b.txt
Parent Figure 3b of main text.
Data description: Processed data for the plot (1st line: Physical quantity, 2nd line: Physical unit, remaining lines: Numerical Data)
2ms Section of the time signal of the positiv half-sine wave measured.
- Filename: fig3c.txt
Parent Figure 3c of main text.
Data description: Processed data for the plot (1st line: Physical quantity, 2nd line: Physical unit, remaining lines: Numerical Data)
RMS ampltiude spectrum of the negative half-sine wave.
- Filename: fig3d.txt
Parent Figure 3d of main text.
Data description: Processed data for the plot (1st line: Physical quantity, 2nd line: Physical unit, remaining lines: Numerical Data)
2ms Section of the time signal of the negative half-sine wave measured.
- Filename: fig3e.txt
Parent Figure 3e of main text.
Data description: Processed data for the plot (1st line: Physical quantity, 2nd line: Physical unit, remaining lines: Numerical Data)
RMS ampltiude spectrum of the full sine wave.
- Filename: fig3f.txt
Parent Figure 3f of main text.
Data description: Processed data for the plot (1st line: Physical quantity, 2nd line: Physical unit, remaining lines: Numerical Data)
2ms Section of the time signal of the full sine wave measured.
- Filename: fig3a+c+e_noise.txt
Parent Figure 3a+c+e of main text.
Data description: Processed data for the plot (1st line: Physical quantity, 2nd line: Physical unit, remaining lines: Numerical Data)
RMS ampltiude spectrum when the RF bias is turned off.
- Filename: fig4a+b.txt
Parent Figure 4a+b of main text.
Data description: Processed data for the plot (1st line: object indicator, 2nd line: Physical quantity, 3nd line: Physical unit, remaining lines: Numerical Data)
Amplitude deviation and THD as a function of applied dither current.
- Filename: fig5a+b.txt
Parent Figure 5a+b of main text.
Data description: Processed data for the plot (1st line: object indicator, 2nd line: Physical quantity, 3nd line: Physical unit, remaining lines: Numerical Data)
Amplitude deviation and THD as a function of laser diode output power.
- Filename: fig5c+d.txt
Parent Figure 5c+d of main text.
Data description: Processed data for the plot (1st line: object indicator, 2nd line: Physical quantity, 3nd line: Physical unit, remaining lines: Numerical Data)
Amplitude deviation and THD as a function of MZM DC bias.
- Filename: fig6a+b.txt
Parent Figure 6a+b of main text.
Data description: Processed data for the plot (1st line: Physical quantity, 2nd line: Physical unit, remaining lines: Numerical Data)
Amplitude deviation and THD as a function of measurement time.
- Filename: fig7.txt
Parent Figure 7 of main text.
Data description: Processed data for the plot (1st line: Physical quantity, 2nd line: Physical unit, remaining lines: Numerical Data)
Amplitude deviation and THD as a function time delay between the optical channels.
recommended software for all: text editor, Excel, Origin
parameters: ADC sampling rate 500 kSa/s, samples per spectrum 50k, further data processing information see main text of publicatio
Liste der bei der PTB angezeigten und geprüften Schusswaffen gemäß § 9 Abs. 2 Nr. 1 Beschussgesetz (BeschG)
No full textListe der bei der PTB angezeigten und geprüften Schusswaffen gemäß § 9 Abs. 2 Nr. 1 Beschussgesetz (BeschG
Liste der von der PTB zugelassenen Schusswaffen gemäß § 8 Beschussgesetz (BeschG)
No full textListe der von der PTB zugelassenen Schusswaffen gemäß § 8 Beschussgesetz (BeschG