I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 European Laser Timing work progress Ivan Procházka, Josef Blažej (1), Jan Kodet (1,2) K.Ulrich Schreiber (2) presented at ACES IWG meeting, Neuchatel, Switzerland, June 2014 (1) Czech Technical University in Prague, Prague 1, Czech Republic (2) Technical University in Munich, Munich, Germany

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 ELT detector work progress, June 2014 Flying unit is manufactured delay caused by ESA soldering qualification process solution found No additional technical problems expected FM will be compared (detection delay) to the ELT Calibration Device before leaving the clean room experimental HW under test at CTU Progress impaired by a re-structuring of a contractor CSRC ltd. company split into two parts - CSRC ltd. Clean rooms, assembly, contract.. - KBmicro ltd. Staff, Electronics, documentation,..

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 ELT Detector package - mobile test bench CTU in Prague, June 2014 Honeycomb optical bench Fibre laser + OPO + SHG laser 531 nm, 100 ps, 10 MHz Focussing optics Beam splitter Start detector ELT detector EM

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 ELT Detector package - mobile test bench CTU in Prague, June 2014 Laser power and synch. Timing system NPET Optical bench ELT detector under test

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 ELT Detector package - mobile test bench CTU in Prague, June hour +/- 2 ps p-p warm up & tuning

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 ACES ELT Ground Station Calibration Request for Proposal, ESA, March, 2014 The ground station will be characterized by a single calibration value / station Calibration value computed from - epoch dif. (E2-E1) - geometry distance L Calibration Device consisting of : - ELT type detector package - Epoch Timing system ET Epoch E1 recorded using standard SLR system Epoch E2 recorded using ELT Calibration Device (Detector & Timing device) Both systems use common time & frequency

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 ELT Calibration Device test # 1, WLRS Fundamental Station Wettzell, Germany, February – May, 2014 ELT type detector package in front of SLR telescope distance surveyed repeatedly (< +/- 1mm) Event timing NPET Epoch reference “1pps” connected consecutively to SLR and ELT timing systems using identical cable (24 m, LRM240) 20 ps RMS

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 ELT Calibration Device Performance Test Fundamental Station Wettzell, Germany, February 13-14, 2014 Timing resolution test 20 Hz, 10 ps laser FWHM, 8% rate Jitter ~ 20 ps rms Dynamical range % (!!!) within +/- 6 ps half p-p (good for SLR tracking..)

I.Prochazka et al,ACES IWG meeting Neuchatel June Hz, 10 ps laser FWHM, 8% rate TDEV s averaging 100 s series simulating ISS / ACES path in all other measurement Resulting in ~ 160 raw readings / path = > ~ 140 valid data points Series to series Stability +/- 1 ps ELT Calibration Device Performance Test Fundamental Station Wettzell, Germany, February 13-14, 2014

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 ELT Calibration Device test # 1, WLRS, March 17 – May 7, 2014 ELT Calibration Long Term Stability 13 ps rms +/- 24 ps p-p 50 days

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 ELT Calibration Device test # 1, WLRS, March 17 Time Scales Re-Synchronization Effect re-sync 20 ps

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 The geometrical distance D = /-1 mm => one way propagation delay (air) DT = /- 3 ps Statistical spread between groups ps without re-sync. effects group to group jumps up to + / - 20 ps p-p due to “1pps” cable delay variations / mechanical Overall mean epochs difference /- 13 ps ( worst case est.) +/- 6 ps omitting outliers ELT calibration value WLRS ET = ps +/- 13 ps ELT Calibration Device test # 1, WLRS RESULTS SUMMARY

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 CONCLUSION - ELT status June 2014 ELT detector FMbeing completed (exp. End 2014) ELT Ground Station Calibration RFP response delivered to ESA start expected mid 2014 The ELT FM delay calibration Test bench assembled and tested FM  Calibration Device expected CSRC Kromeriz, fall 2014 SLR Calibration missionsWLRS demo completed May 7,2014 systematic =< 13 ps demonstrated Graz SLR mission planned July 2014 EU 3 x SLR calibrationspre-launch calibrations 2015 mission run calibrations ? Non EU SLR stations which ones ?

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 Phase meter based on New Pico Event Timer New Pico Event Timer NPET based on SAW filter excitation and frequency domain data processing Extreme timing resolution, stability and linearity Built in generator of synchronous time markers Two channel NPET may be used for phase comparison Key parameters  Timing resolution < 1.3 ps (450 fs)  Timing stability (phase) < +/- 50 fs / K (!!)  Recording rate300 Hz (10 kHz)  Frequencies100/200MHz versus 5/10…..200MHz

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 Phase meter based on New Pico Event Timer LONG TERM STABILITY +/- 0.1 K

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 Phase meter based on New Pico Event Timer TEMPERATURE DRIFT 200 MHz frequency + passive split, equal cables length /- 50 fs /K

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 Phase Meter based on New Pico Event Timer 200 MHz frequency + passive split, equal cables length

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 Phase meter based on New Pico Event Timer TWO MASERS PHASE DIFFERENCE EFTF 2011, published in IEEE

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 Phase meter based on New Pico Event Timer TWO MASERS PHASE DIFFERENCE To be published in RSI Wettzell, Feb. March 2014

I.Prochazka et al,ACES IWG meeting Neuchatel June 2014 Phase meter based on New Pico Event Timer The device is available for ACES