David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August GLAST Pulsar Radio Timing Discussions Report on GLAST Pulsar Radio Timing Discussions at the Prague IAU GA David Smith CENBG/In2p3/CNRS Bordeaux, France August 2006

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Topics Introduction – about the Prague meeting. MAIN POINT – getting the radio TOA’s that we need onto somebody’s disk somewhere. “Bread & butter” pulsars “Most important and most difficult” pulsars Long term DM tracking as well as P, Pdot. A strawman proposal for who does which. Also important point – that those TOA’s become D4.fits ephemeredes “soon”. Data formats, timing conventions & definitions, conversion routines Tempo vs Tempo2 On the merging of TOAs at some future date. Summary of action items Most hyperlinks in this talk can be found at « radio confluence », i.e.

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Intro: radio pulsar people in Prague Roger & Dave T on the JD02 organizing Committee, volunteered me to give “Future Gamma & TeV Observatories for Pulsars” (thank you!) (see talk at radio confluence.) Many attendees are members of Glast Pulsar Advisory Group (see slide 18 of by Steve Thorsett) So organized a Splinter Session (see PragueDiscussion and PragueDiscussionBis at radio confluence.) Well attended, about 20 people, a veritable Who’s Who of radio pulsar people. AGENDA: a) alert them to our ~250 favorite candidates, in hope of defining who- does-which ; b) alert them to D4.fits, to start process of translating their formats and conventions into ours. They’ve been waiting for our call for a couple of years apparently. Eager and very well informed.

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August TOA’s for "bread & butter" pulsars “Bread & butter” pulsars – hundreds of gamma candidates that are relatively easy to measure in radio.

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August The Big Three pulsar telescopes The Big Three pulsar telescopes for long term timing of hundreds of "bread & butter" gamma ray candidates Parkes (Australia) Nançay (France) Jodrell (England)

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August TOA’s for "important but tough" pulsars “key but tough” pulsars – a dozen or so pulsars with the biggest spin-down energies (best gamma ray candidates) but faint radio signals (low S1400, high duty cycle, high Treq

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Green Bank (West Virginia) Oversubscribed – not for bread & butter, only caviar & champagne. Save for e.g. deep searches of new geminga-likes. Arecibo (Puerto Rico) The Big Guns

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Building a strawman proposal Building a strawman proposal (1 of N) We have a list of ~250 gamma pulsar candidates, see confluence radio timing page. Roger calculated Treq and VperY for these, see his TimingTriage.pdf, and If/when Manchester/Parkes & Kramer/Jodrell send me the names of pulsars they’re already tracking, I will look at overlap. But Manchester insists that GLAST (=Roger) should a) ask radio telescopes to state what they can provide (sensitivity, hours, declination) and based on that b) make an initial proposition. Prepare (b) before hearing answer to (a):  1 st iteration – only the Big Three. Offload to other telescopes in 2 nd iteration.  Start from tri.list.xls  Jodrell (Nançay) works down to declination –35° (-39°), Parkes good as far north as  =+2°, so have the Big Three share 0<  -30°.  That is, for  -30°, only Parkes, and for  0°, only Jodrell+Nançay.

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Parkes strawman proposal Parkes strawman proposal (2 of N)  For  -30°, only Parkes.

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Nançay ephemeredes example in TEMPO format Date: Fri, 12 May :56: (CEST) From: Ismael COGNARD ]$ cat J par PSR J RAJ 19:46: DECJ 26:11: POSEPOCH F F E-13 PEPOCH START FINISH DM EPHEM DE200 CLK UNCORR NTOA 99 TRES TZRMJD TZRFRQ TZRSITE f NITS ]$ Over the summer, Nançay completed their de-dispersor and now have the full number of frequency channels. Also, they can now adjust gain so that high backgrounds don’t saturate their electronics (e.g. SNR 3C58 and PSR J )

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Tfghz 1.About

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Sharing the load Effelsberg (Germany) Nanshan (China) Several other instruments can easily time our radio- brighter ( small Treq ) pulsars. Relieve pressure on the Big Three Provide redundant measurements, fill in coverage gaps Special projects, e.g. tracking DM at frequencies besides 1400 MHz, searches for giant pulse correlations, etc. Remember – we need timing for years, but resources at each instrument ebb & flow. Roger’s plan: « lock down the Big Three, then offload to the smaller telescopes ». Many (most!) eager to work with GLAST. ATA (Hat Creek, California)

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Catalog of pulsar radiotelescopes Nanshan (China) List provided with the TEMPO software package:

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Filling D4.fits Getting the radio TOAs properly measured is the Top Priority. But for gtpphase etc to work, also need  TOAs to become proper timing solutions (« ephemeredes »)  Need ephemeredes to get loaded into a D4.fits on the GSSC servers. No show stoppers here. Nevertheless, some work must be done.  TDB versus geocentric time  Reference phase in ms,  s, or mP?  Double precision. Integer + floating parts. Et cetera. The devil is in the details…

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Filling D4.fits, Filling D4.fits, cont’d Everything (we think…) has been foreseen, huge work already done: see e.g. ground.slac.stanford.edu/workbook/pages/sciTools_gtpulsardbEphemerisDataFileTutorial/gtp ulsardbTutorial.htm Very little had been excercised by users. Nançay provided us with some TEMPO ephemeredes outputs, which we have appended to Masa & James CGRO D4.fits example, after conversion to the gtpulsardb my_pubsardb_*.txt format, see Nançay also providing some TOAs, see orleans.fr/~icognard/science/GLAST/ and also We are learning TEMPO – ephemeredes out of a black box won’t allow you to see weak  pulsars, you’ll probably need to know what you’re doing.

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Filling D4.fits more on Filling D4.fits We applied TEMPO to TOA’s on 8 Nançay pulsars, generated ephemeredes, converted to my_pulsardb_*.txt, and loaded into D4.fits. It all worked (yippee!). Except for the my_pulsardb_names.txt part… NEXT – do same excercise for Jodrell & Parkes timing parameters. Kramer & Manchester said they’ll send some sample outputs. ======================================= After this rustic beta-testing, need to industrialize. Masa & James say: format conversion routines should wind up as daemons at GSSC servers, radio-astronomers will send their numbers directly, to get loaded into D4.fits that will (automatically?) wind up on the GSSC servers. Need tools to test validity of final numbers ; need human intelligence for quality control & monitoring. Crab & Vela good, but for all pulsars?

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August TEMPO vs TEMPO2 Dick Manchester seized the discussion on ephemeredes file formats to make a pitch for all radio telescopes to use The others listened attentively and asked many questions. A key feature is better timing precision by using TDB instead of geocentric time. Some had tried it and had installation problems. A priori not our problem but be aware that issues exist.

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August TOAs from Multiple Telescopes Imagine the day you want to stack 5 years of gammas to look for pulsation. Imagine 4 observatories took data on that pulsar over those years, and that D4.fits has 10 or 20 timing solutions with different validity intervals. Suppose further that multifrequency data for different epochs exists, so that you can model DM versus time. You’ll want to build timing solution(s) combining that data intelligently. So, you’ll want the TOAs as well as the parameter templates that were used by the coherent de-dispersors when the raw data, long gone, was reduced. Nançay put some TOAs onto the web for us ; Dick Manchester said « no way! ». I believe that when that day comes, you’ll need to work directly with 4 people from the 4 observatories to build the timing solution(s). Which means we don’t need to worry further about archiving the inputs used to build entries in D4.fits? So long as we have the creators phone numbers?

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Random Comments & Question 1.No significant extra cost to include non-gamma candidates in D4.fits, if more or less valid ephemeredes exist. Should be done… 2.You old-timers lived through a debate we newcomers are unaware of, namely, scan versus point. Pulsar timing experts say POINT! See the reasoning by Paul Ray to the SWG in Dec. 2001, 3.DJT told us about the European Timing Network but I never heard those words in Prague. Quid? Means they pool TOAs? (slide 2 of

David Smith CENBG Report from Prague meeting with Radio Pulsar People PSR Stockholm, 28 August Radio Timing Action Items 1.Refine strawman lists of who does the easy pulsars for us, propose to the radiotelescopes, and iterate. Roger, helped by Dave S. and Steve T? 2.Prepare for the hard pulsars  Refine strawman list  Identify PI’s for time requests at GBT and Arecibo.  Provide PI’s with letter from NASA or LAT PI stating i) vital for GLAST science, ii) coherent program to be shared by all radio telescopes. 3.Continue to excercise D4.fits and pulsar Science Tools with real ephemeredes, from other observatories. Develop QA tools. 4.Affiliated memberships to principal actors. 5.Face to face with radio folks in February or March?