Fermi Detection of a Luminous γ-Ray Pulsar in a Globular Cluster

Contrary to expectations, the γ-rays from a distant cluster of stars are dominated by emission from a single neutron star. We report on the Fermi Large Area Telescope’s detection of γ-ray (>100 mega–electron volts) pulsations from pulsar J1823–3021A in the globular cluster NGC 6624 with high significance (∼7 σ). Its γ-ray luminosity, Lγ = (8.4 ± 1.6) × 1034 ergs per second, is the highest observed for any millisecond pulsar (MSP) to date, and it accounts for most of the cluster emission. The nondetection of the cluster in the off-pulse phase implies that it contains <32 γ-ray MSPs, not ∼100 as previously estimated. The γ-ray luminosity indicates that the unusually large rate of change of its period is caused by its intrinsic spin-down. This implies that J1823–3021A has the largest magnetic field and is the youngest MSP ever detected and that such anomalous objects might be forming at rates comparable to those of the more normal MSPs.

D. Thompson | J. Chiang | J. Grove | A. Moiseev | N. Gehrels | I. Cognard | G. Theureau | R. Blandford | K. Bechtol | L. Cominsky | J. Vandenbroucke | A. Morselli | Z. Yang | T. Tanaka | V. Vitale | H. Sadrozinski | T. Ohsugi | R. Romani | E. Troja | G. Barbiellini | S. Ransom | F. Camilo | P. Freire | A. Lyne | B. Stappers | J. Mcenery | N. Giglietto | P. Spinelli | R. Bellazzini | C. Cecchi | K. Wood | R. Manchester | M. Kramer | H. Takahashi | M. Roth | D. Paneque | S. Ciprini | D. Gasparrini | N. Omodei | M. Keith | A. Van Etten | C. Venter | Y. Fukazawa | T. Mizuno | G. Tosti | F. Longo | J. Ballet | E. Ferrara | T. Tauris | S. Johnston | F. de Palma | E. Bloom | G. Godfrey | E. Bonamente | L. Latronico | A. Chekhtman | P. Lubrano | A. Borgland | R. Claus | T. Glanzman | D. Smith | S. Fegan | J. Kataoka | I. Grenier | P. Caraveo | S. Murgia | J. Cohen-Tanugi | J. Thayer | C. Dermer | T. Nakamori | M. Ozaki | A. Johnson | A. Waite | M. Ziegler | E. do Couto e Silva | L. Guillemot | C. Espinoza | P. Ray | S. Ritz | A. Allafort | D. Bastieri | R. Buehler | S. Buson | R. Cameron | R. Dubois | W. Focke | D. Hadasch | J. Knödlseder | J. Lande | A. Okumura | O. Reimer | L. Tibaldo | D. Torres | A. Harding | M. Kuss | C. Sgro’ | S. Guiriec | M. Brigida | G. Caliandro | C. Favuzzi | F. Gargano | S. Germani | F. Giordano | F. Loparco | M. Mazziotta | C. Monte | M. Pesce-Rollins | S. Rainó | F. Piron | P. Nolan | P. Michelson | M. Kerr | R. Shannon | M. Lemoine-Goumard | P. Fortin | D. Parent | P. Parkinson | E. Charles | P. Fusco | M. Giroletti | G. Jóhannesson | M. Lovellette | I. Moskalenko | E. Nuss | E. Orlando | T. Reposeur | E. Siskind | D. Suson | G. Vianello | T. Johnson | M. Grondin | S. Thorsett | M. Pierbattista | A. Abdo | V. Vasileiou | M. Monzani | S. Zimmer | D. Dumora | S. Lee | J. Norris | T. Porter | P. Smith | N. Vilchez | M. Marelli | P. Bruel | Ö. Çelik | P. Drell | C. C. Cheung | H. Katagiri | P. Wang | M. Dormody | M. Ajello | A. Reimer

[1]  V. Kaspi,et al.  THE BRAKING INDEX OF PSR J1734−3333 AND THE MAGNETAR POPULATION , 2011, 1109.2740.

[2]  A. Kong,et al.  GAMMA-RAY EMISSION FROM THE GLOBULAR CLUSTERS LILLER 1, M80, NGC 6139, NGC 6541, NGC 6624, AND NGC 6752 , 2011, 1101.4106.

[3]  I. Cognard,et al.  Multiwavelength analysis of four millisecond pulsars , 2011, 1101.0669.

[4]  J. Chiang,et al.  A population of gamma-ray emitting globular clusters seen with the Fermi Large Area Telescope , 2010, 1003.3588.

[5]  D. Thompson,et al.  PRECISE γ-RAY TIMING AND RADIO OBSERVATIONS OF 17 FERMI γ-RAY PULSARS , 2010, 1011.2468.

[6]  J. Cordes,et al.  ASSESSING THE ROLE OF SPIN NOISE IN THE PRECISION TIMING OF MILLISECOND PULSARS , 2010, 1010.4794.

[7]  A. Kong,et al.  THE ORIGIN OF GAMMA RAYS FROM GLOBULAR CLUSTERS , 2010, 1009.2278.

[8]  A. Dotter,et al.  THE ACS SURVEY OF GALACTIC GLOBULAR CLUSTERS. X. NEW DETERMINATIONS OF CENTERS FOR 65 CLUSTERS , 2010, 1008.2755.

[9]  I. Busching,et al.  The H-test probability distribution revisited: Improved sensitivity , 2010, 1005.4867.

[10]  E. Striani,et al.  FERMI LARGE AREA TELESCOPE FIRST SOURCE CATALOG , 2010 .

[11]  D. Thompson,et al.  DISCOVERY OF PULSED γ-RAYS FROM PSR J0034−0534 WITH THE FERMI LARGE AREA TELESCOPE: A CASE FOR CO-LOCATED RADIO AND γ-RAY EMISSION REGIONS , 2010 .

[12]  A. Kong,et al.  FERMI DISCOVERY OF GAMMA-RAY EMISSION FROM THE GLOBULAR CLUSTER TERZAN 5 , 2010, 1002.2431.

[13]  J. Chiang,et al.  THE FIRST FERMI LARGE AREA TELESCOPE CATALOG OF GAMMA-RAY PULSARS , 2009, 0910.1608.

[14]  et al,et al.  FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE CRAB PULSAR AND NEBULA , 2009, 0911.2412.

[15]  G. Desvignes,et al.  Nancay radiotelescope as part of the international Pulsar Timing campaigns , 2009 .

[16]  C. Venter,et al.  PROBING MILLISECOND PULSAR EMISSION GEOMETRY USING LIGHT CURVES FROM THE FERMI/LARGE AREA TELESCOPE , 2009, 0911.0872.

[17]  D. Thompson,et al.  A Population of Gamma-Ray Millisecond Pulsars Seen with the Fermi Large Area Telescope , 2009, Science.

[18]  D. Thompson,et al.  Detection of High-Energy Gamma-Ray Emission from the Globular Cluster 47 Tucanae with Fermi , 2009, Science.

[19]  M. Trifoglio,et al.  DISCOVERY OF NEW GAMMA-RAY PULSARS WITH AGILE , 2009, 0903.0087.

[20]  J. Chiang,et al.  THE LARGE AREA TELESCOPE ON THE FERMI GAMMA-RAY SPACE TELESCOPE MISSION , 2009, 0902.1089.

[21]  R. Romani,et al.  AN ATLAS FOR INTERPRETING γ-RAY PULSAR LIGHT CURVES , 2008, 0812.3931.

[22]  D. Thompson,et al.  Pulsar Timing for the Fermi Gamma-ray Space Telescope , 2008, 0810.1637.

[23]  A. Worley,et al.  Nuclear Constraints on the Moments of Inertia of Neutron Stars , 2008, 0801.1653.

[24]  A Parkes radio telescope study of giant pulses from PSR J1823-3021A , 2007 .

[25]  W. Bednarek,et al.  High-energy γ-rays from globular clusters , 2007, astro-ph/0701522.

[26]  F. Ferraro,et al.  Near-Infrared Properties of 24 Globular Clusters in the Galactic Bulge , 2006, astro-ph/0612280.

[27]  R. Manchester,et al.  TEMPO2, a new pulsar-timing package - I. An overview , 2006, astro-ph/0603381.

[28]  D. Lorimer,et al.  Handbook of Pulsar Astronomy , 2004 .

[29]  A. Lyne,et al.  Long-term timing observations of 374 pulsars , 2004 .

[30]  R. N. Manchester,et al.  Further results from the timing of the millisecond pulsars in 47 Tucanae , 2003 .

[31]  J. Dyks,et al.  Two-Pole Caustic Model for High-Energy Light Curves of Pulsars , 2003, astro-ph/0303006.

[32]  A. Fruchter,et al.  Deep Radio Imaging of Globular Clusters and the Cluster Pulsar Population , 1999, astro-ph/9910436.

[33]  F. Camilo,et al.  Coherently Dedispersed Polarimetry of Millisecond Pulsars , 1998, astro-ph/9810399.

[34]  The Commonwealth Scientific and Industrial Research Organisation , 1997, Current Biology.

[35]  Joseph K. Daugherty Alice K. Harding.  Gamma-ray pulsars: emission from extended polar cap cascades , 1995, astro-ph/9508155.

[36]  R. Romani.  Gamma-ray pulsars: Radiation processes in the outer magnetosphere , 1996 .

[37]  A. Fruchter,et al.  Two radio pulsars in the globular cluster NGC 6624 , 1994 .

[38]  E. S. Phinney,et al.  Pulsars as probes of newtonian dynamical systems , 1992, Philosophical Transactions of the Royal Society of London. Series A: Physical and Engineering Sciences.

[39]  W. Goss,et al.  Period Derivative of the Millisecond Pulsar in Globular Cluster M28 , 1988 .

[40]  A. Lyne,et al.  The discovery of a millisecond pulsar in the globular cluster M28 , 1987, Nature.

[41]  C. Ho,et al.  Energetic Radiation from Rapidly Spinning Pulsars. 1. Outer Magnetosphere Gaps. 2. Vela and Crab , 1986 .

[42]  C. Ho,et al.  Energetic radiation from rapidly spinning pulsars. II: Vela and Crab , 1986 .

[43]  J. Arons.  Pair creation above pulsar polar caps : geometrical structure and energetics of slot gaps. , 1983 .

[44]  M. Morini.  Inverse Compton gamma-ray from pulsars − I. The Vela pulsar , 1983 .

[45]  A. Cheng,et al.  A new class of radio pulsars , 1982, Nature.

[46]  A. Harding,et al.  Electromagnetic cascades in pulsars , 1982 .