David Smith CENBG Plans for Radio Pulsar Timing GLAST collaboration meeting, Stockholm, 30 August 2006 1 Radio Timing for GLAST Pulsars Radio Timing for

David Smith CENBG 1

Plans for Radio Pulsar Timing GLAST collaboration meeting, Stockholm, 30 August 2006Radio Timing for GLAST PulsarsRadio Timing for GLAST PulsarsGLAST LAT collaboration meeting

Stockholm, August 2006

David Smith for the PSR SNR PWNe groupCENBG/In2p3/CNRS Bordeaux, France

Parkes (Australia)

Nançay (France)

Jodrell (England)

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Plans for Radio Pulsar Timing GLAST collaboration meeting, Stockholm, 30 August 2006

Pulsar, Supernova Remnant, Plerion Pulsar, Supernova Remnant, Plerion Science Group ReportScience Group ReportD.J. Thompson & R.W. Romani, co-leaders

AgendaAgenda

• Report on radio timing planning (David Smith) - 20 min. Report on radio timing planning (David Smith) - 20 min. • Report on X-ray timing planning (Joe Dolan) - 10 min Report on X-ray timing planning (Joe Dolan) - 10 min • Report on DC2 results (Alice Harding) - 20 min. Report on DC2 results (Alice Harding) - 20 min. • Discussion of DC3 needs (Francesco Longo) - 10 min. Discussion of DC3 needs (Francesco Longo) - 10 min. • Discussion of papers, especially LAT paper (Roger Discussion of papers, especially LAT paper (Roger

Romani) - 20 min. Romani) - 20 min.

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TopicsTopics

"Good ephemeredes will dramatically enhance pulsar (and PWN) science"

-- Roger Romani, in "Radio Timing for GLAST: Requirements, Costs, and Triage'' , 21 Feb 2006

1. Why we need a lot of radio pulsar timing

2. Which radio telescopes are expected to make which measurements

3. Distillation: protocol for radio ephemeredes to reach D4.fits file(s) on the LAT servers.

Most hyperlinks in this talk can be found at "radio confluence", i.e.

https://confluence.slac.stanford.edu/display/SCIGRPS/Radio+timing+for+GLASTand in any case they’re active links in the powerpoint.

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Galaxy of pulsars animation by Michael Kramer (Manchester/Jodrell)

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Why we need radio timing of pulsarsWhy we need radio timing of pulsars

1. 10x better pulsed sensitivity than without accurately known period• DC2 seems to confirm

• N_true = N_observed/Ntrials, and Ntrials large for blind search.

• Timing noise makes blind search harder for multi-month data

2. Signatures of beam geometry and acceleration region & mechanism are in the variations of light curves with wavelength.

3. Most gamma ray pulsar candidates are young & noisy. That means, the rotation parameters (ephemeredes) "spoil" within weeks to months, so the radio measurements need to be repeated perdiodically throughout the mission.

4. GLAST won't point first year – will see all pulsars "all" the time. Slow accumulation of gammas over time requires long term accurate timing.

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EphemerEphemereedes des sooner, not latersooner, not later

• Realize later that PSR Jxxxx+yy might have been a good one?

TOO LATE, you can’t go back, see e.g. 2229+6114 in astro-ph/0112518.

(Thompson Digel Nolan Reimer)

Fun fact : 600+ radio pulsars in Joe Fierro's "EGRET pulsars" thesis;

1400+ plus when I started with ATNF late last year ;

1500+ early this year ;

1600+ during the Spring ;

Presently 1775….

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CGRO had the same issueCGRO had the same issue

"Worse" for GLAST LAT: 3x more known pulsars, 25x more sensitivity.

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Which are GLAST's candidates?Which are GLAST's candidates?

• Study of the huge* sample of known gamma pulsars leads to the conclusion that Edot/d² is a good predictor of gamma ray emission, where Edot=dE/dt is the the rotation spin-down energy .

• Distance "d" often poorly known (derived from DM=Dispersion Measure

and model of electron density in interstellar space), so hedge bets by also keeping large Edots.

* That's a joke, son.

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Gamma ray pulsarsGamma ray pulsars

From G. Kanbach, 363rd Heraeus seminar, May 2006 – other authors order these differently…



Gamma ray pulsar candidatesGamma ray pulsar candidates

• We made a list of 255 candidates, applying some convienient cuts to the ATNF database. All known "favorites" are (hopefully!) included.

CUT N' PASTE OF THE ATNF WWW EXPERT MENU:

User-defined variables

C1 (sqrt(Edot)/Dist1/Dist1)/5.362E18 ( normalize to ~Crab)

Sort on field C1 Order Descending

Condition

(Edot>1E34 || (sqrt(Edot)/Dist1/Dist1)/5.362E18 > 0.01) (~1% of Crab)



Plot du ciel entier (1627 pulsars) et des pulsars sélectionnés sur critères ("vrais pulsars")

1,00E-21

1,00E-20

1,00E-19

1,00E-18

1,00E-17

1,00E-16

1,00E-15

1,00E-14

1,00E-13

1,00E-12

1,00E-11

1,00E-10

1,00E-09

0,001 0,01 0,1 1 10 100

Période de rotation Po (en s)

Ral

enti

ssem

ent

P1

Ciel entier (1627 Pulsars)

Pulsars choisis par critères (236)

Pulsars EGRET

GLAST’s gamma candidates, compared to all known pulsars and the CGRO 7, prepared by J. Petit & C. Loumena



TOA’s for TOA’s for ""bread & butterbread & butter"" pulsars pulsars

• “Bread & butter” pulsars – a couple of hundred gamma candidates that are relatively easy to measure in radio.

• Roger defines Treq and VperY in his "TimingTriage.pdf":

Treq: 100 meter class time (hours) required for needed Time-of-arrival (TOA) precision;

VperY: Visits per Year to not loose count of neutron star rotations (depends mainly on Pdot)

• "Easy" means (Treq < 1 hour) for a 100 meter class telescope and (VperY < 3)

• For Treq<0.1 h, small telescopes can do.

• We will load into D4.fits any valid ephemeredes we can get our hands on, and search for gamma pulsations at those positions (even if no DC excess, apologies to Jean Ballet et al – remember PSR B1951+32 in EGRET!).



The Big Three pulsar telescopesThe Big Three pulsar telescopesfor long term timing of hundreds of "bread & butter" gamma ray candidates

Parkes (Australia)

Nançay (France)

Jodrell (England)



TOA’s for TOA’s for ""important but toughimportant but tough"" pulsars pulsars

• “key but tough” pulsars – a dozen or two pulsars with the biggest spin-down energies (best gamma ray candidates) but faint radio signals (low S1400, high duty cycle, high b'grd makes high Treq) and large VperY.

• [ For radio flux density at 1400 MHz S1400 < 25 µJy, use X-ray satellites when possible, see Joe Dolan's presentation. ]



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 GunsThe Big Guns



Building a strawman proposalBuilding a strawman proposal

• Take list of 255 gamma pulsar candidates, see confluence radio timing page and next slide.

Calculate Roger’s Treq and VperY (my code is in strawman.tar at radio confluence)

Jodrell (Nançay) works down to declination –35° (-39°), Parkes good as far north as =+2°.

63 "Northern", 129 "Parkes", 62 "Either". Therefore, "eithers" better shared by Jodrell & Parkes, that is, 63+62=125 with -30° for those two.



Parkes strawman proposal Parkes strawman proposal (first 32 of 129, sorted by Treq)

similar for the Northern telescopes…

(a lot of) bread n' butter

Ouch!

Name JName Fvel Dec p0 p1 w50 s1400 Treq VperY TperYJ0024-7204O J0024-7204O 0.000343 -72.1 0.003 3.00E-20 1.20 0.6000 9.1943 0.09 9.194B0540-69 J0540-6919 0.000165 -69.3 0.050 5.00E-13 18.00 0.0240 2805.6223 9.31 26117.879J0535-6935 J0535-6935 0.000003 -69.6 0.201 1.00E-14 25.00 0.0500 27.4285 0.83 27.428J1735-3258 J1735-3258 0.000052 -33.0 0.351 3.00E-14 187.50 0.4600 25.4942 0.80 25.494J0024-7204Q J0024-7204Q 0.000193 -72.1 0.004 3.00E-20 1.20 0.6000 2.5884 0.07 2.588J0024-7204U J0024-7204U 0.000288 -72.1 0.004 1.00E-19 1.20 0.6000 2.0733 0.10 2.073J0737-3039A J0737-3039A 0.008793 -30.7 0.023 2.00E-18 14.30 1.6000 12.1519 0.16 12.152J1124-5916 J1124-5916 0.003671 -59.3 0.135 7.00E-13 15.00 0.0800 11.0567 6.54 72.301B1259-63 J1302-6350 0.003620 -63.8 0.048 2.00E-15 23.00 1.7000 1.9792 1.28 2.542J1626-4807 J1626-4807 0.000065 -48.1 0.294 2.00E-14 57.00 0.3700 1.8847 0.76 1.885B0021-72E J0024-7204E 0.000399 -72.1 0.004 1.00E-19 0.90 0.6000 1.6200 0.12 1.620J1015-5719 J1015-5719 0.001102 -57.3 0.140 6.00E-14 46.00 0.9000 1.5533 2.02 3.131J0855-4644 J0855-4644 0.002121 -46.7 0.065 7.00E-15 7.50 0.2000 1.3786 1.47 2.033J1019-5749 J1019-5749 0.000277 -57.8 0.162 2.00E-14 44.00 0.8000 1.0974 1.20 1.315J1933-6211 J1933-6211 0.007138 -62.2 0.003 4.00E-21 0.36 0.4200 0.7078 0.05 0.708B0021-72F J0024-7204F 0.000506 -72.1 0.003 6.00E-20 0.50 0.6000 0.6802 0.12 0.680J1538-5551 J1538-5551 0.000186 -55.9 0.105 3.00E-15 11.00 0.2500 0.6569 0.77 0.657J1301-6305 J1301-6305 0.000908 -63.1 0.185 3.00E-13 28.00 0.4600 0.5841 3.10 1.810J0711-6830 J0711-6830 0.002500 -68.5 0.005 1.00E-20 1.90 1.6000 0.5726 0.04 0.573J1248-6344 J1248-6344 0.000130 -63.7 0.198 2.00E-14 12.00 0.1200 0.5442 0.98 0.544J1524-5625 J1524-5625 0.007093 -56.4 0.078 4.00E-14 12.00 0.8300 0.5261 3.60 1.895J1357-6429 J1357-6429 0.008957 -64.5 0.166 4.00E-13 15.00 0.4400 0.4821 5.74 2.765J1734-3333 J1734-3333 0.000176 -33.6 1.169 2.00E-12 164.10 0.5000 0.3914 2.13 0.836J0024-7204T J0024-7204T 0.000219 -72.1 0.008 3.00E-19 1.20 0.6000 0.3886 0.11 0.389J1052-5954 J1052-5954 0.000156 -59.9 0.181 2.00E-14 11.00 0.1500 0.3553 1.12 0.396J1509-5850 J1509-5850 0.003397 -58.8 0.089 9.00E-15 4.70 0.1500 0.3155 1.45 0.458J1551-5310 J1551-5310 0.000147 -53.2 0.453 2.00E-13 62.00 0.5400 0.3102 1.50 0.466J1632-4757 J1632-4757 0.000170 -48.0 0.229 2.00E-14 21.00 0.3000 0.3049 0.85 0.305J1617-5055 J1617-5055 0.002667 -50.9 0.069 1.00E-13 5.80 0.2800 0.2815 4.63 1.304J2124-3358 J2124-3358 0.034997 -34.0 0.005 2.00E-20 0.51 1.6000 0.2140 0.12 0.214J1413-6141 J1413-6141 0.000227 -61.7 0.286 3.00E-13 37.00 0.6100 0.2067 2.53 0.523J1138-6207 J1138-6207 0.000183 -62.1 0.118 1.00E-14 12.00 0.4900 0.1567 1.23 0.193



Sharing the loadSharing the load

Effelsberg (Germany)

Nanshan (China)

Some other instruments can time our radio-brighter (small Treq) but noisier (large VperY) 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.

• Many (most!) eager to work with GLAST.

ATA (Hat Creek, California)



Report on GLAST Pulsar Radio Timing Discussions GLAST Pulsar Radio Timing Discussions

at the Prague IAU GA

David Smith w. D. DumoraCENBG/In2p3/CNRS Bordeaux, France

16-17 August 2006



GLAST radio timing "splinter session" GLAST radio timing "splinter session" atat Prague 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 http://glast.gsfc.nasa.gov/ssc/resources/guc/050606/MultiwaveObs.pdf 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 pulsarers.

• 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. Eager and very well informed.



So? What's the plan?So? What's the plan?

• Bread & butter:

Northern hemisphere, no real issue – most already being timed. Coordinate to make sure that all are, in a coherent way. The radio astronomers are in touch with each other.

Southern hemisphere – Parkes is the only big pulsar instrument. Not automated, requires shifters. Proposal has to be made & defended (Simon Johnston), and they request help for a person-year (e.g. student or technician).

• Important but tough

A few being timed anyway.

A few to be offloaded to X-ray instruments.

The others to be subjects of specific proposals

• Current key task – clarify exactly who does which how, then support PI's in writing and defending their proposals. Steve Thorsett and/or Roger Romani will be coordinating via personal contacts.



Filling D4.fits*Filling D4.fits*

• For gtpphase etc to work like in DC2, need

TOAs to become proper timing solutions ("ephemeredes")

Ephemeredes must get loaded into a D4.fits on the GSSC servers.

• D. Dumora wrote code² that takes TEMPO output from Nançay, Jodrell, etc and converts it to the .txt format prescribed for gtpulsardb.

• We appended 13 Nançay & Jodrell pulsars to the ~1100 CGRO ephemeredes in the D4.fits sample provided by Masa H & James P at GSSC3. The whole chain works, tuning in progress.

*Don't know what "D4.fits" means? Go to pulsar section of the SAS workbook and look for ephemeredes database, or look at e.g. Max Razzano's DC2 tutorials.

² http://www.cenbg.in2p3.fr/ftp/astropart/Smith/Pulsars/NançayTempoToLATascii.htm

3 http://glast.gsfc.nasa.gov/ssc/dev/psr_tools/definitionD4.html



more on Filling D4.fits Filling D4.fits

• After this rustic beta-testing, will industrialize.

• Format conversion routines will become daemons at GSSC servers. Radio-astronomers will send their numbers to get loaded into D4.fits that will wind up on the GSSC servers*.

• Need tools to test validity of final numbers (quality control).

* Tom Stephens already has these structures in place.



Conclusion: Pulsar Timing Action ItemsConclusion: Pulsar Timing Action Items

1. Refine lists of who does which, propose to the radiotelescopes, and iterate.

2. Identify PI’s for time requests at GBT, RXTE, etc. Support proposal preparation.

3. Continue to load D4.fits with real ephemeredes, and excercise Science Tools. Develop QA tools.

4. Help provide manpower or $$$ to radio observatories.

Documents

David Smith CENBG Plans for Radio Pulsar Timing GLAST collaboration meeting, Stockholm, 30 August 2006 1 Radio Timing for GLAST Pulsars Radio Timing for