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Pulsar Ephemerides for Timing LAT Pulsars

Timing pulsars with the LAT requires the use of an ephemeris that covers the time period being analyzed. Below are several resources to provide this useful input to your analysis. These include:

High E-dot Radio timing models — Provided by the Pulsar Timing Consortium.
Ephemerides for Radio-faint or Radio-quiet LAT Pulsars — Provided by the LAT team.
Pulsar Timing Models used in LAT Team Publications — Provided by the LAT team to allow replication of published analyses.

Please remember that the collection and analysis of radio and LAT data that goes into generating each ephemeris is a significant time investment. Remember to acknowledge the source of the ephemeris and any appropriate references should you use any of these ephemerides for a publication. Please email the timing contact for the pulsar ephemeris you have used, or contact the Fermi helpdesk if you have any questions regarding this policy.

LAT List of Detected Gamma-Ray Pulsars

Pulsar Timing Models from LAT data

Some pulsars are radio quiet, or can be better timed using LAT data than radio data. For the most recent timing solutions for these pulsars, please go to the Fermi LAT Gamma-ray Pulsar Timing page.

Pulsar Timing Models Used in LAT Publications

The following table includes pulsar timing files used in publications of Fermi pulsars. The publication reference is given after the file listing. The radio template is provided when available.

The rotation parameters are available as TEMPO, TEMPO2 and PINT ".par" files:

The .par files are described at http://www.atnf.csiro.au/research/pulsar/tempo2/inde.php?n=Documentation.Parameters .
TEMPO is described at http://www.atnf.csiro.au/research/pulsar/tempo/ .
TEMPO2 is described at http://www.atnf.csiro.au/research/pulsar/tempo2/ .
PINT is described by Luo, J., Ransom, S., Demorest, P., et al. 2021, ApJ, 911, 45 doi: 10.3847/1538-4357/abe62f .

When using these timing solutions in a publication, please refer to the following reference(s), depending on the radio instrument(s) used to obtain them (given in the table below):

GBT: details are given for each pulsar in the "Publication Reference" listed below
Parkes: P. Weltevrede, et al., 2010, PASA, 27, 64
Jodrell Bank: G. Hobbs, A.G. Lyne, M. Kramer, C.E. Martin, C. Jordan, 2004, MNRAS, 353, 1311
Nançay: G. Theureau, N. Coudreau, N. Hallet, M. Hanski, L. Alsac, et al., 2005, A&A, 430, 373
Arecibo: A. Dowd, W. Sisk, J. Hagen, 2000, ASC Conf. Ser., 202, 275
Westerbork: J.L.L. Voûte, M.L.A. Kouwenhoven, P.C. van Haren, J.J. Langerak, B.W. Stappers, et al., 2002, A&A, 385, 733

Table of Published Ephemerides

Pulsar Name	Timing Files	Timing Instrument	Timing Model Contact	Publication Reference	Contact Author(s)
3PC catalog: 294 pulsars (see paper)	Available on the 3PC page.	LAT and radio telescopes (see Table 4 of the 3PC paper)	See the contact authors at the bottom of 3PC page.	"The Third Fermi Large Area Telescope Catalog of Gamma-ray Pulsars", Smith et al. 2023 doi: 10.48550/arXiv.2307.11132	Same as Timing Model Contact
J1227-4853	.par profile	Parkes	Simon Johnston	"Discovery of Gamma-ray Pulsations from the Transitional Redback PSR J1227-4853" Johnson, T. J. et al. 2015, ApJ, submitted. arxiv:1502.06862	Tyrel Johnson Paul Ray Jayanta Roy
J2032+4127	best.par isolated.par	Jodrell/ LAT/GBT	Andrew Lyne	"The Binary Nature of PSR J2032+4127" Lyne, A. G. et al. 2015, MNRAS, accepted. arxiv:1502.01465	Andrew Lyne
J1055-6028 J1640+2224 J1705-1906 J1732-5049 J1843-1113 J1913+0904	.tgz	Multiple Sources	Xian Hou David Smith	"Six Faint Gamma-ray Pulsars Seen with the Fermi Large Area Telescope" Hou, X. et al. 2014, A&A, 570, 44. doi:10.1051/0004-6361/201424294	Xian Hou David Smith Lucas Guillemot
B1821-24	.par 2GHz profile 1.4GHz profile 0.3GHz profile .tgz	Nançay/WRST Nançay Nançay Westerbork	Lucas Guillemot Ismael Cognard Ben Stappers	"Broadband Pulsations from PSR B1821-24: Implications for Emission Models and the Pulsar Population of M28" Johnson, T. J. et al., ApJ, 2013 778, 106 doi:10.1088/0004-637X/778/2/106	Tyrel Johnson Lucas Guillemot Matthew Kerr Ismael Cognard Paul Ray
J1544+4937	.par	GMRT	Bhaswati Bhattacharyya	"GMRT discovery of PSR J1544+4937: an eclipsing black-widow pulsar identified with a Fermi-LAT source" Bhattacharyya, B. et al. 2013, ApJL, 773, L12. doi:10.1088/2041-8205/773/1/L12	Bhaswati Bhattacharyya Jayanta Roy Paul Ray
117 gamma-ray pulsars (see paper)	.tgz	Multiple Sources	Matthew Kerr David Smith	"The Second Fermi Large Area Telescope Catalog of Gamma-ray Pulsars" A. A. Abdo et al. 2013, ApJS, 208, 17. doi:10.1088/0067-0049/208/2/17	Ozlem Celik Peter den Hartog Matthew Kerr Joshua Lande David Smith
J2030+3641	.par	GBT	Fernando Camilo	"PSR J2030+3641: Radio Discovery and Gamma-Ray Study of a Middle-aged Pulsar in the Now Identified Fermi-LAT Source 1FGL J2030.0+3641" Camilo, F. et al. 2012, ApJ, 746, 39. doi:10.1088/0004-637X/746/1/39	Fernando Camilo Matthew Kerr Paul Ray
J1856+0245	.par	Jodrell Bank	Ben Stappers David Smith	"Study of the Pulsar Wind Nebula HESS J1857+026 with Fermi-LAT" Rousseau R. et al. 2012, A&A, 544, A3 . doi:10.1051/0004-6361/201118685	Ben Stappers David Smith
J1939+2134 J1959+2048	.par profile profile .par profile profile	Nançay/WRST Nançay Westerbork Nançay/WRST Nançay Westerbork	Lucas Guillemot Ismael Cognard Ben Stappers Gemma Janssen	"Pulsed Gamma Rays from the Original Millisecond and Black Widow Pulsars: A Case for Caustic Radio Emission?" Guillemot, L., et al. 2012, ApJ, 744, 33 doi:10.1088/0004-637X/744/1/33	Lucas Guillemot Tyrel Johnson Christo Venter Matthew Kerr
J1125-5825 J1446-4701	.par profile .par profile	Parkes Parkes	Simon Johnston Simon Johnston	"The High Time Resolution Universe Pulsar Survey - IV. Discovery and polarimetry of millisecond pulsars" Keith, M. J., et al., 2012, MNRAS, 419, 1752 doi:10.1111/j.1365-2966.2011.19842.x	Mike Keith
J1823-3021A	.par profile	Nançay/ Jodrell	Ismael Cognard Damien Parent	"Fermi Detection of a Luminous γ-Ray Pulsar in a Globular Cluster" Freire, P. C. C. et al., 2011, Science, 334, 1107 doi:10.1126/science.1207141	Paolo Freire Tyrel Johnson Damien Parent Christo Venter
J2021+4026	.par	LAT	Max Razzano	"The identification of the X-ray counterpart to PSR J2021+4026" Weisskopf, M. C. et al., 2011, ApJ, 743, 74 doi:10.1088/0004-637X/743/1/74	Martin Weisskopf Max Razzano P. Saz Parkinson Andrea Belfiore
B1259-63	.par	Parkes	Simon Johnston	"Discovery of High-energy Gamma-ray Emission from the Binary System PSR B1259-63/LS 2883 around Periastron with Fermi" Abdo, A. A. et al. 2011, ApJ, 736, 11 doi:10.1088/2041-8205/736/1/L11	Aous Abdo Damien Parent Kent Wood Simon Johnston Andrii Neronov
J2017+0603 J2302+4442	.par profile .par profile	Nançay Nançay	Lucas Guillemot Lucas Guillemot	"Discovery of Two Millisecond Pulsars in Fermi Sources with the Nançay Radio Telescope" Cognard, I. et al. 2011, ApJ, 732, 47 doi:10.1088/0004-637X/732/1/47	Ismael Cognard Lucas Guillemot Tyrel Johnson
J2241-5236	.par	LAT	Mike Keith	"Discovery of millisecond pulsars in radio searches of southern Fermi Large Area Telescope sources" Keith, M. J., et al. 2011, MNRAS, 414, 1292 doi:10.1111/j.1365-2966.2011.18464.x	Mike Keith
J0007+7303 J0357+3206 J0633+0632 J1124-5916 J1418-6058 J1459-6053 J1732-3131 J1741-2054 J1809-2332 J1813-1246 J1826-1256 J1836+5925 J1907+0602 J1958+2846 J2021+4026 J2032+4127 J2238+5903	.par .par .par .par .par .par .par .par .par .par .par .par .par .par .par .par .par .tgz	LAT (for all)	Paul Ray (for all)	"Precise Gamma-Ray Timing and Radio Observations of 17 Fermi Gamma-Ray Pulsars" Ray, P.S., et al. 2011, ApJS, 194, 17 doi:10.1088/0067-0049/194/2/17	Paul Ray
J2043+2740	.par profile	Jodrell	Aristeidis Noutsos	"Radio and γ-ray Constraints on the Emission Geometry and Birthplace of PSR J2043+2740" Noutsos, A., et al. 2011, ApJ, 728, 77 doi:10.1088/0004-637X/728/2/77	Aristeidis Noutsos Lucas Guillemot
J0614-3329 J1231-1411 J2214+3000	.par .par .par	GBT GBT GBT	Scott Ransom Scott Ransom Scott Ransom	"Three Millisecond Pulsars in Fermi LAT Unassociated Bright Sources" Ransom, S.M. et al. 2011, ApJ, 727, 16 doi:10.1088/2041-8205/727/1/L16	Scott Ransom Paul Ray
J0007+7303 J0030+0451 J0034-0534 J0205+6449 J0218+4232 J0248+6021 J0357+3206 J0437-4715 J0534+2200 J0613-0200 J0631+1036 J0633+0632 J0633+1746 J0659+1414 J0742-2822 J0751+1807 J0835-4510 J1023-5746 J1028-5820 J1044-5737 J1048-5832 J1057-5226 J1124-5916 J1413-6205 J1418-6058 J1420-6048 J1429-5911 J1459-6053 J1509-5850 J1614-2230 J1709-4429 J1718-3825 J1732-3131 J1741-2054 J1744-1134 J1809-2332 J1813-1246 J1826-1256 J1833-1034 J1836+5925 J1846+0919 J1907+060 J1952+3252 J1954+2836 J1957+5033 J1958+2846 J2021+3651 J2021+4026 J2032+4127 J2043+2740 J2055+2539 J2124-3358 J2229+6114 J2238+59	.tgz	Multiple Sources	Marie-Hélène Grondin (for all)	"Fermi-LAT Search for Pulsar Wind Nebulae Around Gamma-ray Pulsars" Ackermann, M. et al, ApJ, 2011, 726, 35. doi:10.1088/0004-637X/726/1/35	J. Lande A. Van Etten A. Harding M. Grondin M. Lemoine
J1023-5746 J1044-5737 J1413-5205 J1429-5911 J1846+0919 J1954+2836 J1957+5033 J2055+25	.par .par .par .par .par .par .par .par .tgz	LAT (for all)	Paul Ray (for all)	"Eight γ-ray Pulsars Discovered in Blind Frequency Searches of Fermi LAT Data" Saz Parkinson, P.M. et al, ApJ, 2010, 725, 571. doi:10.1088/0004-637X/725/1/571	P. Saz Parkinson Michael Dormody Marcus Ziegler Paul Ray
J0248+6021 J2240+5832	.par profile .par profile	Parkes GBT/Jodrell	Ismael Cognard Ismael Cognard	"PSRs J0248+6021 and J2240+5832, young pulsars in the northern galactic plane: Discovery, timing, and gamma-ray observations" Theureau, G. et al. 2011, A&A, 525, A94 doi:10.1051/0004-6361/201015317	David Smith Damien Parent Gilles Theureau
Geminga (B0630+18) (J0633+1746)	D4 .par	LAT	Paul Ray	"Fermi LAT observations of the Geminga pulsar" Abdo, A. A. et al. 2010, ApJ, 720, 272 doi:10.1088/0004-637X/720/1/272	Massimiliano Razzano Fabio Gargano Denis Dumora
J1513-5908	.par	Parkes	Simon Johnston	"Detection of the energetic pulsar PSR B1509-58 and its pulsar wind nebula in MSH 15-52 using the Fermi Large Area Telescope" Abdo, A. A. et al. 2010, ApJ, 714, 927 doi:10.1088/0004-637X/714/1/927	Peter den Hartog Marie-Helene Grondin Marianne Lemoine Takeshi Nakamori
Vela (B0833-45) (J0835-4510)	.par	LAT	Paul Ray	"The Vela Pulsar: Results from the First Year of Fermi LAT Observations" Abdo, A. A. et al. 2010, ApJ, 713, 154. doi:10.1088/0004-637X/713/1/154	Alice Harding Tyrel Johnson Matthew Kerr Ozlem Celik Andrea Caliandro
J0034-0534	.par 1.4GHz profile 0.3GHz profile .tgz	Nançay/WRST Nançay Westerbork	Lucas Guillemot Ismael Cognard Ben Stappers	"Discovery of Pulsed Gamma rays from PSR J0034-0534 with the Fermi LAT: A Case for Co-located Radio and Gamma-ray Emission Regions" Abdo, A. A. et al., ApJ, 2010 712, 957 doi:10.1088/0004-637X/712/2/957	Lucas Guillemot Alice Harding Tyrel Johnson Christo Venter
J0631+1036 J0659+1414 J0742-2822 J1420-6048 J1509-5850 J1718-3825	.par .par .par .par .par .par .tgz	Nançay/Jodrell Nançay/Parkes Nançay/Jodrell Parkes Parkes Nançay/Parkes	Cognard/Stappers Cognard/Johnston Cognard/Stappers Simon Johnston Simon Johnston Cognard/Johnston	"Gamma-ray and Radio Properties of Six Pulsars Detected by the Fermi Large Area Telescope" P. Weltevrede et al, ApJ, 2010, 708, 1426. doi:10.1088/0004-637X/708/2/1426	P. Weltevrede Simon Johnston David Smith
J0534+2200 CORRECTION: 4 milliperiod gamma-ray phase shift	.par profile README .tgz	Nançay/Jodrell	Cognard/Stappers	"Fermi Large Area Telescope Observations of the Crab Pulsar and Nebula" Abdo, A. A. et al. 2010, ApJ, 708, 1254 doi:10.1088/0004-637X/708/2/1254	Francesco Loparco Nicola Mazziota Marie-Helene Grondin Marianne Lemoine
J1048-5832 J2229+6114	.par profile .par profile	Parkes GBT/Jodrell	Simon Johnston Camilo/Stappers	"Fermi LAT detection of pulsed gamma-rays from the Vela-like pulsars PSR J1048-5832 and PSR J2229+6114" Abdo, A. A. et al., ApJ, 2009, 706, 1331 doi:10.1088/0004-637X/706/2/1331	Alice Harding Damien Parent Massimiliano Razzano
J0007+7303 J0030+0451 J0205+6449 J0218+4232 J0248+6021 J0357+32 J0437-4715 J0534+2200 J0613-0200 J0631+1036 J0633+0632 J0633+1746 J0659+1414 J0742-2822 J0751+1807 J0835-4510 J1028-5819 J1048-5832 J1057-5226 J1124-5916 J1418-6058 J1420-6048 J1459-60 J1509-5850 J1614-2230 J1709-4429 J1718-3825 J1732-31 J1741-2054 J1744-1134 J1747-2958 J1809-2332 J1813-1246 J1826-1256 J1833-1034 J1836+5925 J1907+06 J1952-3252 J1958+2826 J2021+3651 J2021+4026 J2032+4127 J2043+2740 J2124-3358 J2229+6114 J2238+59	.par .par profile .par profile .par profile .par profile .par .par profile .par profile .par profile .par profile .par .par .par profile .par profile .par profile .par profile .par .par profile .par profile .par profile .par .par profile .par .par profile .par profile .par profile .par profile .par .par profile .par profile .par profile .par .par .par .par profile .par .par .par profile .par .par profile .par .par profile .par profile .par profile .par profile .par .tgz	LAT Nançay GBT Nançay/WSRT Nançay LAT Parkes Nançay/Jodrell Nançay Jodrell/Nançay LAT LAT Nançay/Parkes Nançay/Parkes Nançay Parkes Parkes Parkes Parkes Parkes/LAT LAT Parkes LAT Parkes GBT Parkes Parkes LAT GBT Nançay GBT LAT LAT LAT GBT LAT LAT Nançay LAT GBT LAT GBT Nançay Nançay GBT/Jodrell LAT	Paul Ray Ismael Cognard Fernando Camilo Cognard/Stappers Ismael Cognard Paul Ray Simon Johnston Cognard/Stappers Ismael Cognard Stappers/Cognard Paul Ray Paul Ray Cognard/Johnston Cognard/Johnston Ismael Cognard Simon Johnston Simon Johnston Simon Johnston Simon Johnston Johnston/Ray Paul Ray Simon Johnston Paul Ray Simon Johnston Fernando Camilo Simon Johnston Simon Johnston Paul Ray Fernando Camilo Ismael Cognard Fernando Camilo Paul Ray Paul Ray Paul Ray Fernando Camilo Paul Ray Paul Ray Ismael Cognard Paul Ray Fernando Camilo Paul Ray Fernando Camilo Ismael Cognard Ismael Cognard Camilo/Stappers Paul Ray	"The First Fermi Large Area Telescope Catalog of Gamma-ray Pulsars" Abdo, A. A. et al, ApJS, 2010, 187, 460. doi:10.1088/0067-0049/187/2/460	Andrea Caliandro Elizabeth Ferrara Damien Parent Roger Romani
J0030+0451 J0218+4232 J0437-4715 J0613-0200 J0751+1807 J1614-2230 J1744-1134 J2124-3358	.par radioprofile .par radioprofile .par radioprofile .par radioprofile .par radioprofile .par radioprofile .par radioprofile .par radioprofile .tgz	Nançay Nançay & Westerbork Parkes Nançay Nançay GBT Nançay Nançay	Ismael Cognard Ismael Cognard Ben Stappers Simon Johnston Ismael Cognard Ismael Cognard Fernando Camilo Ismael Cognard Ismael Cognard	"A Population of Gamma-Ray Millisecond Pulsars Seen with the Fermi Large Area Telescope" Abdo, A. A. et al, Science, 2009, 325, 848. doi:10.1126/science.1176113	Lucas Guillemot Tyrel Johnson Matthew Kerr David Smith
J0007+7303 J0357+32 J0633+0632 J1418-6058 J1459-60 J1732-31 J1741-2054 J1809-2332 J1813-1246 J1826-1256 J1836+5925 J1907+06 J1958+2846 J2021+4026 J2032+4127 J2238+59	D4 .par tempo2	LAT	Paul Ray	"Detection of 16 Gamma-Ray Pulsars Through Blind Frequency Searches Using the Fermi LAT" Abdo, A. A. et al, Science, 2009, 325, 840. doi:10.1126/science.1175558	Michael Dormody Paul Ray Pablo Saz Parkinson Marcus Ziegler
J2021+3651	D4 .par tempo radioprofile	GBT	Fernando Camilo	"Pulsed gamma-rays from PSR J2021+3651 with the Fermi Large Area Telescope" Abdo, A. A. et al, ApJ, 2009, 700, 1059. doi:10.1088/0004-637X/700/2/1059	Lucas Guillemot David Smith Matthew Kerr
J0030+0451	D4 .par tempo radioprofile	Nançay	Ismael Cognard	"Pulsed Gamma-rays from the millisecond pulsar J0030+0451 with Fermi" Abdo, A. A. et al, ApJ, 2009, 699, 1171. doi:10.1088/0004-637X/699/2/1171	Lucas Guillemot Tyrel Johnson Matthew Kerr
J0205+6449	D4 .par tempo radioprofile	GBT/Jodrell	Camilo/Stappers	"Discovery of Pulsations from the Pulsar J0205+6449 in SNR 3C 58 with the Fermi Gamma-ray Space Telescope" Abdo et al, ApJL, 2009 699, L102. doi:10.1088/0004-637X/699/2/L102	Damien Parent
Vela (B0833-45) (J0835-4510)	D4 .par tempo2 radioprofile	Parkes	Simon Johnston	" Fermi LAT Observations of the Vela Pulsar" Abdo, A. A. et al. 2009, ApJ, 696, 1084. doi:10.1088/0004-637X/696/2/1084	Roger Romani Max Razzano
J1028-5819	D4 .par tempo2 radioprofile	Parkes	Simon Johnston	"Discovery of Pulsed Gamma Rays from the Young Radio Pulsar PSR J1028-5819 with the Fermi Large Area Telescope" Abdo, A. A. et al. 2009, ApJL, 695, L72. doi:10.1088/0004-637X/695/1/L72	Alice Harding Tyrel Johnson

Note: When using links in the table to send mail to contact authors or to radio contacts, please replace "at" with "@" and "dot" with "." in the email address before sending.

Pulsar Timing Models in D4 Format - Obsolete

Epoch folding pulsars with the Fermitools (e.g. using gtpphase and gtpsearch) requires use of a pulsar ephemeris database in the D4 FITS format (based on the EGRET pulsar analysis). It is prudent to use the timing models provided for analysis only within the validity range specified within the file. The accuracy of the models may degrade rapidly outside that range, particularly for noisy pulsars. A single D4 FITS file containing timing information for the LAT pulsars to date is available here:

Fermi_PulsarDB_v001.fits (Posted 2009 Aug 24), to be read by the Fermitools, as discussed in Smith, Guillemot et al A&A 492, 923 (2008) (DOI:10.1051/0004-6361:200810285) and detailed in the FSSC documentation .

NOTE: The pulsar ephemerides in the FSSC D4 database are provided as a courtesy by the original observers. Users are STRONGLY encouraged to contact the timing observers for the most current information about any pulsar.

High E-dot Pulsar Radio Timing Models - Obsolete

Prior to the launch of Fermi, a group of radio and X-ray astronomers organized a "Fermi pulsar timing consortium" to provide rotation ephemerides for 224 pulsars known at that time to have spin-down power Edot > 10³⁴ erg/s. This campaign is described in Smith et. al, 2008 The consortium agreed to make their work publicly available after Fermi's first year in orbit, to allow phase-folding of gamma-ray pulsars and pulsar-candidates by scientists using data from the Large Area Telescope (LAT). The rotation ephemerides for 216 pulsars for which timing was obtained, in the form of TEMPO2 parameter files, are available here:

HighEdot_ephems_v1.tar (Posted 2010 Dec 23)

Please take a moment to review the information in the README file before using the data for analysis or publication. Users are STRONGLY encouraged to contact the timing observers for the most current information about any pulsar.

Last updated by: Nestor Mirabal

National Aeronautics and Space Administration

Goddard Space Flight Center