Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 1 Update on Pulsar timing for GLAST with the Nançay Radio telescope David Smith et al CENBG/In2p3/CNRS Bordeaux, France

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 2 Topics 1.Big Nançay time request submitted today, see form-NRT-Avril2006_HE4.pdf at a)Two glast lists – Roger’s 10 pilot pulsars, and 138 gamma candidates b)Joint GLAST+HESS+XMM request “French High Energy Pulsars” 2.About Nançay sensitivity… (work in progress) 3.Does a “pre-flight” D4 database exist? And a few other little questions.

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 3 Nançay time request due today Initially, planned to study Roger’s 10 pulsars, to quantify sensitivity, and gradually ramp up our program. But count backwards, and realize you better pick up the pace:  Sept D4 database full  Summer building timing solutions  Fall making periodic radio measurements of many pulsars, to be used to build ephemeredes.  Spring 2006 – big time request We have submitted a list of ~140 pulsars and request >500 hours for the 2 nd half of Requesting “key program” status.

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 4 The ~140 pulsars Our cuts on ATNF: Edot > 1E34.OR. sqrt(Edot)/d² > 1% of Crab This gives all the famous pulsars (all the obvious and less obvious candidates), including a healthy sample of ms pulsars. Declination > -39.5° (Smith was wrong when he said that Nançay poops out north of  ~ +60°.) The GLAST request is part of a more general “High Energy Pulsars in the French Community” proposal which includes 8 pulsars associated with HESS galactic sources ( Yves Gallant, Montpellier ) and 2 binaries to be observed with XMM ( Natalie Webb, Toulouse ). All 10 of the HESS+XMM pulsars are in the GLAST list, as are all 10 of Roger’s test cases. As work continues the GLAST list will evolve – the TAC shouldn’t bother us about the exact list. Dave T re-made the list using the NE2001 distances from the “expert” ATNF www pages for the full sky, see PulsarListBordeauxFormula.xls &.pdf at There are 250 pulsars. Includes Geminga and 2 other “radio quiets”, J (SNR Kes 75) & J (G ).

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 5 How we calculate telescope time Roger’s Feb 21 “Timing Triage” talk is our meat & potatoes. He used f_gamma = sqrt(Edot)/d² normalized to Vela’s value to sort targets by “expected” gamma brightness. He said that the time required for a 10 mP T.O.A. scales as (W/P) 1.5 /S_1400, and he normalized to 3 hours on Roger, where did you get that “3 hour” number from? Nançay saw (?) it with signal-to-noise ~9 in 92 minutes in January, not as clear as they’d like. Work in progress. Nançay picked up a few other tricky ones, so we’re normalizing “treq” to those. (Nançay has detected 80 pulsars since BON installed 2 years ago, most of them repeatedly.)

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 6 Best of 4 observations. Ismael trying to improve.

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 7 From Tue Jan 31 20:00: To: D.A. Smith Subject: some glast pulsars Hi David -- as requested, here are a few pulsars that you can discuss in your upcoming meeting with Ismael. I will describe some of my thinking in ranking things on the 21st. But here are 10 PSR worth discussing, all above DEC -35. Note -- many of these are presently being timed, although it is not clear that the timing is adequate or will continue during GLAST. You might want to avoid competing in the Arecibo DEC range (0-38), as well: Ridiclously difficult, but important: Name ~S_1.4(mJy) J J J J e Not so hard, but likely interesting J J J J J J e Anyway, something to discuss, although certainly not an exhaustive list. Let me know what Ismael thinks Roger Roger’s test pulsars Discovered last year. 62 ms, both Edot/d 2 and B LC greater than for e.g f_gamma. Discovered in ‘95, no published timing since (no publications, period!). Serious fun -- galactic center, 3EG and HESS TeV sources nearby, big Edot/d 2, called the “Mouse”. Bow shock visible in Xrays.

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 8 Roger classed this as “ridiculously hard” but it is easily detectable. ATNF doesn’t have S1400 for this one, so RWR extrapolates from 400 MHz assuming a 2.5 spectral index, apparently an underestimate in this case. Also, ATNF doesn’t have W50, so RWR takes W/P = 10% but here it’s even narrower.  One neutron star rotation  28 slices, 2 minutes each

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 9 Ismael is (understandably!) proud that Nançay achieves 0.6/435 = 1 mP timing in about 2 minutes. Nota bene: a few points over a few months to get P and Pdot.

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 10 (this slide re-cycled from my 21 February talk…) Ismael had J with 60 +/- 20 uJy in his list. Pops out in less than an hour. BUT Roger says the 60  Jy isn’t reliable. I read the references, they seem fine to me… Roger, do you still disbelieve the 60  Jy ? A 60  Jy ms pulsar

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 11 This one has S mJy but the timing parameters in the literature are a bit off. Ismael & Gilles load the ephemeredes into the BON de-dispersor front-end, which does heavy processing of terabytes of data. The raw data is lost. From this detection, refine the parameters, and iterate. This is part of why it’s good to get a head-start.  One neutron star rotation  2 minute slices This is also one of the 10 HESS targets.

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 12 Ismael made this slide for the January workshop. Denis and I have fiddled with his list, to demonstrate RWR’s (W/P) 1.5 /S_1400 law. Again, more of a guideline than a hard & fast rule. Sensitivity… (W/P)/S_1400?  S_1400 

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 13 Telescope time, cont’d You’ve seen that RWR’s “treq” is a useful guideline but not a rigorous prediction. In “TimingTriage” Roger also estimated “visits per year”, based on  8, from this reference: We’d like to write the same article, next year… … but they took >3 years!

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 14 “Visits per Year” not an exact science In consequence, at Nançay measurements of large numbers of “our” pulsars will allow us to nail down just how often we’ll need to come back to any given pulsar, in addition to knowing how long to dwell on any single pulsar. Step 1: make sure you’re detecting ‘em. Step 2: detect ‘em a few times over many months Step 3: build timing solutions and load them into the D4 database.

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 15 (brief parentheses – What’s TEMPO for?) At our last meeting, Marcus Ziegler showed results of his DC2 blind searches. MRF0054 brighter than Vela! We plugged his f, fdot into gtpphase – after one day the light curves get washed out. Fiddled with f,fdot by hand, looking at this “radio-like” plot. Say… isn’t this what TEMPO is for? How do you “build timing solutions” anyway? Our radio pals know, but I think we need too, before launch. 55 days Of DC2

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 16 Towards a post-launch D4 database I presume that someone has already built a D4 ephemeredes database and exercised the Science Tools with it… Like: take all the ephemeredes in ATNF and just load ‘em in. That would be our starting point. Then, as GBT Jodrell Nançay Parkes Arecibo send fresh ephemeredes to various of us, we’ll have some standard procedure for making it propagate to the Official versions at the data servers, right? Like, we give them to Peachy and Masa or?… The D4.fits file has an “observer” column. That’s for traceability, right? Presumably, a given pulsar at time t may have ephemeredes from later from one radio telescope and from earlier from another; and we’ll want to connect the two (with TEMPO?) ; and we want to avoid a large N_trials… ; is there a plan for all this? Is barycentering and phase calculation foreseen to be part of gamma ray reconstruction?

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 17 DC2 Version 2 All Sky Damien Parent ran his scripts over the new, improved V2 DC2 sky. Flip through his 98 pages – it’s fun, they look great. Here’s page 96. PSF cut done (“dist < 500/E”). Not big effect, investigating. Here, 3°cut. Will study sensitivity & localisation.

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 18 Conclusions A French 100-meter class radio telescope with modern pulsar electronics is working with GLAST to time faint, young, and noisy pulsars over our mission lifetime. We have submitted a request for >500 hours to time ~140 pulsars beginning in the 2 nd half of 2006, and aim to become one of three “key programs” at Nançay. Goal is to stock the D4 database with fresh products. Timing measurements have begun. We’re ramping up faster than previously planned. Various questions are raised, none of which are critical path items.

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 19 Appendix Extra slides

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 20 About the 140 pulsars As stated: at Nançay we’re planning to attack the whole dang list. At some point in the next months it makes sense to start finding out which of the 140 are already being monitored elsewhere. (Thanksgiving’s probably soon enough…) (from Steve Thorsett transparencies)

Pulsar timing with Nançay, and DC2, cont’d Pulsar working group, 2 May 2006 David Smith 21 Introduction to Nançay It is a meridian telescope : sources visible ~1 hour per day, at transit. South mirror fixed (300 m x 35 m), north mirror tilts (200m x 40m), little trolley car ( shown below ) moves to focus. ( 94 m diameter equivalent ) Covers -40 o <  < 60 o ( best for -30 o <  < 40 o ) Lobe is 21’ north-south x 4’ east-west ( at 21 cm ~ 1400 MHz ) 2.5 M$ refurbishing 5 years ago, big pulsar improvements 2 years ago Some performance details in a galaxy survey paper, G. Theureau et al, A&A (2005)