An arrival time file (.tim)TelescopeSite arrivalStates that this is a tempo2codetime(MJD)format fileFORMAT1/pulsar/20cm/m2002-12-10-13:00:00.czFTp1404.734 52618.59030437804791.909-f MULTI CPSR2n -CaL 11404.734 52618.59030437804791.909-f MULTI CPSR2n-Cal1/pulsar/20cm/m2002-12-10-13:39:58.czFTp1341.331 52618.59026488495561.494/pulsar/20cm/n2002-12-10-13:00:00.czFTp-fMULTICPSR2m-Cal1/pulsar/20cm/n2002-12-10-13:39:58.czFTp1341.331 52618.59026488495561.494YMULTI CPSR2m-CaL1/pulsar/20cm/m2002-12-14-14:41:47.czFTp1404.736 52622.62118121246502.459MULTI CPSR2n -Cal 11341.42752622.6211782913951MULTI CPSR2m -Cal 1/pulsar/20cm/n2002-12-14-14:41:47.czFTp976/pulsar/20cm/m2002-12-15-14:25:37.czFTp1405.23552623.6455892166404.496MULTI CPSR2n -Cal 11341.500 52623.64559005263481.145fMULTI CPSR2m-Cal 1/pular/20cm/n2002-12-15-14:25:37.czFTp/pulsar/20cm/m2003-02-04-09:24:09.czFTp1404.736 52674.41371289708341.846FMULTICPSR2n-Cal1/pulsar/20cm/n2003-02-04-09:24:09.czFTp1341.267 52674.41370412900171.883f MULTI CPSR2m-cal1/pulsar/50cm/m2003-02-07-08:21:20.czFTp658.95452677.36100043276560.7667F50CMCPSR2-Cal1/pulsar/50cm/m2003-02-07-10:01:43.czFTp659.22052677.43864008053350.74550CM_CPSR2-Cal1660.19052742.42606217919241.4687-f50CMCPSR2-Ca1/pular/50cm/m2003-04-13-10:03:28.czFTp1404.49352795.04851826706241.5967-fMULTI_CPSR2n-Cal1/pul5ar/20cm/m2003-06-05-00:56:26.czFTp/pul5ar/20cm/n2003-06-05-00:56:26.czFTp1340.976 52795.0485170472312 1.130 7-fMULTI CPSR2m -Cal 1/pulsar/20cm/m2003-06-05-01:32:02.czFTp1404.48052795.0848331525075:408f MULTI CPSR2n -Cal 1/pulsar/20cm/n2003-06-05-01:32:02.czFTp1340.98752795.08479440051091.060f MULTI CPSR2m -Cal 1/pulsar/50cm/m2003-06-06-06:12:48.czFTp660.00252796.27461580768290.5727-f50CMCPSR2-ca1/pulsar/20cm/m2003-07-25-23:30:54.czFTp1404.44552846.02153280273661.0347-fMULTI_CPSR2n-cal1Filename or identifierUser definedObservingUncertainty onflagsfrequency (MHz)arrival time (us)CSIRO
An arrival time file (.tim) States that this is a tempo2 format file Filename or identifier Observing frequency (MHz) Site arrival time (MJD) Uncertainty on arrival time (us) Telescope code User defined flags
Howdoestempo2work?.ThealgorithmsarebasedonthoseimplementedinTEMPO1.DetailsinHobbs,Edwards&Manchester(2006)andEdwardsHobbs&Manchester(2006)SecularClockShapiro delayEinstein delaymotion (e.g.,correctionsradial velocity)+Aso - D/f? +At = Ac +VP+B+ AEo + ARO*DispersiveRoemerdelayOrbitaldelayConversion ofmotionsite-arrival-Atmospherictime to pulsedelaysemissiontime川CSIR
How does tempo2 work? • The algorithms are based on those implemented in TEMPO1 • Details in Hobbs, Edwards & Manchester (2006) and Edwards, Hobbs & Manchester (2006) Conversion of site-arrivaltime to pulse emission time Clock corrections Atmospheric delays Einstein delay Shapiro delay Roemer delay Secular motion (e.g., radial velocity) Dispersive delay Orbital motion
Details:clock correctionAt = Ac + AA + ABo + Aro + Aso - D/f? + Avp + ABMustconvertfromtheobservatorytimestandardtoarealisationofterrestrialtimeTT.Use set of text files containingthedifferencebetweentwotimestandards:pks2gps.clk,gps2utc.clk,utc2tai.clk,tai2tt bipm201164.5You'llfindthese64files in$TEMPO2/clock63.5(s) 1 -oenasgodirectory6362.56261.5615000051000515005350050500520005250053000MJD
Details: clock correction • Must convert from the observatory time standard to a realisation of terrestrial time TT. Use set of text files containing the difference between two time standards: pks2gps.clk, gps2utc.clk, utc2tai.clk, tai2tt_bipm2011. You’ll find these files in $TEMPO2/clock directory
Details:Einsteindelay+ ARo + Aso - D/ f? + △vp + △BAt = Ac + AA + AEO.Pulse arrival times (interrestrialtime)mustbe convertedto theframeoftheSolarSystemBarycentreTEMPO2usesthetabulatedresultsofIrwin&Fukushima(1999)13.51312.512(s)011.5A11上10.5109.5950000515005350d5050051000520005250053000MJD
Details: Einstein delay • Pulse arrival times (in terrestrial time) must be converted to the frame of the Solar System Barycentre. • TEMPO2 uses the tabulated results of Irwin & Fukushima (1999)
Details:Roemer delay+ △so - D/ f?+△vp + △BAt = Ac + AA + AEO + AROTheRoemerdelayisthevacuumlighttraveltimebetweenthepulsearrivingattheobservatoryandtheequivalentarrivaltimeat the SSBpulsarUseobservatorycoordinatefiletoknowpositionofobservatonK=Unit vectorpointing atpulsar.ObtainedfromSSBEarthRA,DEC,RisvectorfromobservatoryPMRA,toSSB.UseJPLephemerisPMDECobservatorycoordinatesandearthorientationparametersCSIR
Details: Roemer delay • The Roemer delay is the vacuum light travel time between the pulse arriving at the observatory and the equivalent arrival time at the SSB. R k Earth SSB pulsar K = Unit vector pointing at pulsar. Obtained from RA, DEC, PMRA, PMDEC R is vector from observatory to SSB. Use JPL ephemeris, observatory coordinates and earth orientation parameters Use observatory coordinate file to know position of observatory