Mostrando recursos 1 - 20 de 681

  1. L'astronomie dans le monde - 04/2017

    Manfroid, Jean
    Molécules organiques sur Cérès – Jets bleus – Pulsar lointain – Comète 73P/Schwassmann-Wachmann

  2. PSR J1618-3921: a recycled pulsar in an eccentric orbit

    Octau, F.; Cognard, I.; Guillemot, L.; Tauris, T.M.; Freire, P.C.; Desvignes, G.; Theureau, G.
    PSR~J1618$-$3921 is an $11.99$-ms pulsar in a $22.7$-d orbit around a likely low-mass He white dwarf companion, discovered in a survey of the intermediate Galactic latitudes at 1400 MHz conducted with the Parkes radio telescope in the late 1990s. Although PSR~J1618$-$3921 was discovered more than 15 years ago, only limited information has been published about this pulsar which has a surprisingly large orbital eccentricity ($e \simeq 0.027$), considering its high spin frequency and likely small companion mass. The focus of this work is a precise measurement of the spin, astrometric and orbital characteristics of PSR J1618$-$3921. This was done with...

  3. Temperature and cooling age of the white dwarf companion of PSR J0218+4232

    Bassa, C. G.; van Kerkwijk, M. H.; Kulkarni, S. R.
    We report on Keck optical BVRI images and spectroscopy of the companion of the binary millisecond pulsar PSR J0218+4232. A faint bluish (V = 24.2, B - V = 0.25) counterpart is observed at the pulsar location. Spectra of this counterpart reveal Balmer lines which confirm that the companion is a helium-core white dwarf. We find that the white dwarf has a temperature of T_(eff) = 8060 ± 150 K. Unfortunately, the spectra are of insufficient quality to put a strong constraint on the surface gravity, although the best fit is for low log g and hence low mass (~0.2...

  4. The Anomalous X-ray Pulsar 4U 0142+61: Variability in the infrared and a spectral break in the optical

    Hulleman, F.; van Kerkwijk, M. H.; Kulkarni, S. R.
    We present new optical and infrared observations of the counterpart to the Anomalous X-ray Pulsar (AXP) 4U 0142+61 taken with the Keck I telescope. The counterpart is found to be variable in the infrared. This contrasts with our optical observations, which do not show any evidence for variability. Apart from the variability the AXP shows a remarkable spectral energy distribution. In particular, we find a sudden drop in flux going from V to B, presumably due to a spectral feature. We compare our results to those obtained for the two other securely identified AXP counterparts, to 1E 2259+586 and 1E...

  5. Probing the nature of AX J0043-737: Not an 87 ms pulsar in the SMC

    Maitra, C.; Ballet, J.; Esposito, P.; Haberl, F.; Tiengo, A.; Filipovic, M.D.; Acero, F.
    AX J0043-737 is a source in the ASCA catalogue, the nature of which is uncertain. It is most commonly classified as a Crab-like pulsar in the Small Magellanic Cloud (SMC) following apparent detection of pulsations at ~ 87 ms from a single ASCA observation. A follow-up ASCA observation was not able to confirm this, and the X-ray detection of the source has not been reported since. With a dedicated XMM-Newton, observation, we studied the nature of the source. We ascertained the source position, searched for the most probable counterpart and studied the X-ray spectrum. We also analysed other archival observations...

  6. Detection of 16 Gamma-Ray Pulsars Through Blind Frequency Searches Using the Fermi LAT

    Abdo, A.A.; Ackermann, Markus; Ajello, Marco; Anderson, B.; B. Atwood, W.; Axelsson, M.; Baldini, Luca; Ballet, J.; Barbiellini, Guido; G. Baring, M.; Bastieri, D.; M. Baughman, B.; Bechtol, K.; Bellazzini, R.; Berenji, B.; F. Bignami, G.; D. Blandford, R.; D. Bloom, E.; Bonamente, E.; W. Borgland, A.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; H. Burnett, T.; A. Caliandro, G.; A. Cameron, R.; Caraveo, P. A.; Casandjian, J.M.; Cecchi, C.; Celik, O.; Chekhtman, A.; C. Cheung, C.; Chiang, J.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Conrad, J.; Cutini, S.; D. Dermer, C.; De Angelis, A.; De Luca, A.; De Palma, F.; W. Digel, S.; Dormody, M.; Do Couto E Silva, E.; S. Drell, P.; Dubois, R.; Dumora, D.; Farnier, C.; Favuzzi, C.; J. Fegan, S.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Gehrels, N.; Germani, S.; Giebels, B.; Giglietto, N.; Giommi, P.; Giordano, F.; Glanzman, T.; Godfrey, G.; A. Grenier, I.; Grondin, M.-H.; E. Grove, J.; Guillemot, L.; Guiriec, S.; Gwon, C.; Hanabata, Y.; K. Harding, A.; Hayashida, M.; Hays, E.; E. Hughes, R.; Johannesson, G.; P. Johnson, R.; J. Johnson, T.; N. Johnson, W.; Kamae, T.; Katagiri, H.; Kataoka, J.; Kawai, N.; Kerr, M.; Knodlseder, J.; L. Kocian, M.; Kuss, M.; Lande, J.; Latronico, L.; Lemoine-Goumard, M.; Longo, F.; Loparco, F.; Lott, B.; N. Lovellette, M.; Lubrano, P.; M. Madejski, G.; Makeev, A.; Marelli, M.; N. Mazziotta, M.; Mcconville, W.; E. Mcenery, J.; Meurer, C.; F. Michelson, P.; Mitthumsiri, W.; Mizuno, T.; Monte, C.; E. Monzani, M.; Morselli, A.; V. Moskalenko, I.; Murgia, S.; L. Nolan, P.; P. Norris, J.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orlando, E.; F. Ormes, J.; Paneque, D.; Parent, D.; Pelassa, V.; Pepe, M.; Pesce-Rollins, M.; Pierbattista, M.; Piron, F.; Porter, T.A.; R. Primack, J.; Raino, S.; Rando, R.; S. Ray, P.; Razzano, M.; Rea, N.; Reimer, A.; Reimer, O.; Reposeur, T.; Ritz, S.; S. Rochester, L.; Y. Rodriguez, A.; W. Romani, R.; Ryde, F.; F.-W. Sadrozinski, H.; Sanchez, D.; Sander, A.; M. Saz Parkinson, P.; D. Scargle, J.; Sgro, C.; J. Siskind, E.; Smith, David Stanley; D. Smith, P.; Spandre, G.; Spinelli, P.; Starck, Jean-Luc; S. Strickman, M.; J. Suson, D.; Tajima, H.; Takahashi, H.; Takahashi, T.; Tanaka, T.; G. Thayer, J.; J. Thompson, D.; Tibaldo, L.; Tibolla, O.; F. Torres, D.; Tosti, G.; Tramacere, A.; Uchiyama, Y.; L. Usher, T.; Van Etten, A.; Vasileiou, V.; Vilchez, N.; Vitale, V.; P. Waite, A.; Wang, P.; Watters, K.; L. Winer, B.; T. Wolff, M.; S. Wood, K.; Ylinen, T.; Ziegler, M.
    Pulsars are rapidly rotating, highly magnetized neutron stars emitting radiation across the lectromagnetic spectrum. Although there are more than 1800 known radio pulsars, until recently, only seven were observed to pulse in gamma rays and these were all discovered at other wavelengths. The Fermi Large Area Telescope makes it possible to pinpoint neutron stars through their gamma-ray pulsations. We report the detection of 16 gamma-ray pulsars in blind frequency searches using the LAT. Most of these pulsars are coincident with previously unidentified gamma-ray sources, and many are associated with supernova remnants. Direct detection of gamma-ray pulsars enables studies of emission...

  7. Observation of Supernova remnant IC 443 with the Fermi Large Area Telescope

    A. Abdo, A.; Ackermann, Markus; Ajello, Marco; Baldini, Luca; Ballet, J.; Barbiellini, Guido; Bastieri, D.; M. Baughman, B.; Bechtol, K.; Bellazzini, R.; Berenji, B.; D. Blandford, R.; D. Bloom, E.; Bonamente, E.; W. Borgland, A.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; H. Burnett, T.; Buson, S.; A. Caliandro, G.; A. Cameron, R.; Caraveo, P. A.; M. Casandjian, J.; Cecchi, C.; Celik, O.; Chekhtman, A.; C. Cheung, C.; Chiang, J.; N. Cillis, A.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; R. Cominsky, L.; Conrad, J.; Cutini, S.; D. Dermer, C.; De Angelis, A.; De Palma, F.; Do Couto E Silva, E.; S. Drell, P.; Drlica-Wagner, A.; Dubois, R.; Dumora, D.; Farnier, C.; Favuzzi, C.; J. Fegan, S.; B. Focke, W.; Fortin, P.; Frailis, M.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Gehrels, N.; Germani, S.; Giavitto, G.; Giebels, B.; Giglietto, N.; Giordano, F.; Glanzman, T.; Godfrey, G.; A. Grenier, I.; Grondin, M.-H.; E. Grove, J.; Guillemot, L.; Guiriec, S.; Hanabata, Y.; K. Harding, A.; Hayashida, M.; E. Hughes, R.; S. Jackson, M.; Johannesson, G.; S. Johnson, A.; J. Johnson, T.; N. Johnson, W.; Kamae, T.; Katagiri, H.; Kataoka, J.; Kawai, N.; Kerr, M.; Knodlseder, J.; L. Kocian, M.; Kuss, M.; Lande, J.; Latronico, L.; Lee, S.-H.; Lemoine-Goumard, M.; Longo, F.; Loparco, F.; Lott, B.; N. Lovellette, M.; Lubrano, P.; M. Madejski, G.; Makeev, A.; N. Mazziotta, M.; Meurer, C.; F. Michelson, P.; Mitthumsiri, W.; A. Moiseev, A.; Monte, C.; E. Monzani, M.; Morselli, A.; V. Moskalenko, I.; Murgia, S.; Nakamori, T.; L. Nolan, P.; P. Norris, J.; Nuss, E.; Ohsugi, T.; Orlando, E.; F. Ormes, J.; Ozaki, M.; Paneque, D.; H. Panetta, J.; Parent, D.; Pelassa, V.; Pepe, M.; Pesce-Rollins, M.; Piron, F.; Porter, T.A.; Raino, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Reposeur, T.; S. Rochester, L.; Y. Rodriguez, A.; W. Romani, R.; Roth, M.; Ryde, F.; F.-W. Sadrozinski, H.; Sanchez, D.; Sander, A.; M. Saz Parkinson, P.; D. Scargle, J.; Sgro, C.; J. Siskind, E.; Smith, David Stanley; D. Smith, P.; Spandre, G.; Spinelli, P.; S. Strickman, M.; W. Strong, A.; J. Suson, D.; Tajima, H.; Takahashi, H.; Takahashi, T.; Tanaka, T.; B. Thayer, J.; G. Thayer, J.; J. Thompson, D.; Tibaldo, L.; F. Torres, D.; Tosti, G.; Tramacere, A.; Uchiyama, Y.; L. Usher, T.; Van Etten, A.; Vasileiou, V.; Venter, C.; Vilchez, N.; Vitale, V.; P. Waite, A.; Wang, P.; L. Winer, B.; S. Wood, K.; Ylinen, T.; Ziegler, M.
    We report observation of the supernova remnant (SNR) IC 443 (G189.1+3.0) with the Fermi Gamma-ray Space Telescope Large Area Telescope (LAT) in the energy band between 200 MeV and 50 GeV. IC 443 is a shell-type SNR with mixed morphology located off the outer Galactic plane where high-energy emission has been detected in the X-ray, GeV and TeV gamma-ray bands. Past observations suggest IC 443 has been interacting with surrounding interstellar matter. Proximity between dense shocked molecular clouds and GeV–TeV gamma-ray emission regions detected by EGRET, MAGIC, and VERITAS suggests an interpretation that cosmic-ray (CR) particles are accelerated by the...

  8. Fermi Large Area Telescope observations of the Vela-X Pulsar Wind Nebula

    Abdo, A.A.; Ackermann, Markus; Ajello, Marco; Allafort, A.; Baldini, Luca; Ballet, J.; Barbiellini, Guido; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Berenji, B.; D. Blandford, R.; D. Bloom, E.; Bonamente, E.; W. Borgland, A.; Bouvier, A.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; H. Burnett, T.; Buson, S.; A. Caliandro, G.; A. Cameron, R.; Caraveo, P. A.; Carrigan, S.; M. Casandjian, J.; Cecchi, C.; Celik, O.; Chekhtman, A.; C. Chung, C.; Chiang, J.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Conrad, J.; De Angelis, A.; De Palma, F.; Dormody, M.; Do Couto E Silva, E.; S. Drell, P.; Dubois, R.; Dumora, D.; Farnier, C.; Favuzzi, C.; J. Fegan, S.; B. Focke, W.; Fortin, P.; Frailis, M.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gehrels, N.; Germani, S.; Giavitto, G.; Giglietto, N.; Giordano, F.; Glanzman, T.; Godfrey, G.; A. Grenier, I.; Grondin, M.-H.; E. Grove, J.; Guillemot, L.; Guiriec, S.; K. Harding, A.; Hayashida, M.; Hays, E.; Horan, D.; E. Hughes, R.; S. Jackson, M.; Johannesson, G.; S. Johnson, A.; J. Johnson, T.; N. Johnson, W.; Johnston, S.; Kamae, T.; Katagiri, H.; Kataoka, J.; Kawai, N.; Kerr, M.; Knodlseder, J.; Kuss, M.; Lande, J.; Latronico, L.; Lee, S.-H.; Lemoine-Goumard, M.; Llena Garde, M.; Longo, F.; Loparco, F.; Lott, B.; N. Lovellette, M.; Lubrano, P.; Makeev, A.; Marelli, M.; N. Mazziotta, M.; E. Mcenery, J.; Meurer, C.; F. Michelson, P.; Mitthumsiri, W.; Mizuno, T.; A. Moiseev, A.; Monte, C.; E. Monzani, M.; Morselli, A.; V. Moskalenko, I.; Murgia, S.; Nakamori, T.; L. Nolan, P.; P. Norris, J.; Noutsos, A.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orlando, E.; F. Ormes, J.; Ozaki, M.; Paneque, D.; H. Panetta, J.; Parent, D.; Pelassa, V.; Pepe, M.; Pesce-Rollins, M.; Pierbattista, M.; Piron, F.; Porter, T.A.; Raino, S.; Rando, R.; S. Ray, P.; Rea, N.; Reimer, A.; Reimer, O.; Reposeur, T.; Ritz, S.; Y. Rodriguez, A.; W. Romani, R.; Roth, M.; Ryde, F.; F.-W. Sadrozinski, H.; Sanchez, D.; Sander, A.; M. Saz Parkinson, P.; D. Scargle, J.; Sgro, C.; J. Siskind, E.; Smith, David Stanley; D. Smith, P.; Spandre, G.; Spinelli, P.; S. Strickman, M.; J. Suson, D.; Tajima, H.; Takahashi, H.; Takahashi, T.; Tanaka, T.; B. Thayer, J.; G. Thayer, J.; J. Thompson, D.; Tibaldo, L.; F. Torres, D.; Tosti, G.; Tramacere, A.; Uchiyama, Y.; L. Usher, T.; Van Etten, A.; Vasileiou, V.; Venter, C.; Vilchez, N.; Vitale, V.; P. Waite, A.; Wang, P.; Weltevrede, P.; L. Winer, B.; S. Wood, K.; Ylinen, T.; Ziegler, M.
    21 pages, 5 figures, accepted for publication in Astrophysical Journal

  9. The Vela Pulsar: Results from the First Year of Fermi LAT Observations

    A. Abdo, A.; Ackermann, Markus; Ajello, Marco; Allafort, A.; B. Atwood, W.; Baldini, Luca; Ballet, J.; Barbiellini, Guido; G. Baring, M.; Bastieri, D.; M. Baughman, B.; Bechtol, K.; Bellazzini, R.; Berenji, B.; D. Blandford, R.; D. Bloom, E.; Bonamente, E.; W. Borgland, A.; Bouvier, A.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; H. Burnett, T.; Buson, S.; A. Caliandro, G.; A. Cameron, R.; Caraveo, P. A.; Carrigan, S.; M. Casandjian, J.; Cecchi, C.; Celik, O.; Chekhtman, A.; C. Cheung, C.; Chiang, J.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Conrad, J.; D. Dermer, C.; De Luca, A.; De Palma, F.; Dormody, M.; Do Couto E Silva, E.; S. Drell, P.; Dubois, R.; Dumora, D.; Farnier, C.; Favuzzi, C.; J. Fegan, S.; B. Focke, W.; Fortin, P.; Frailis, M.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Gehrels, N.; Germani, S.; Giavitto, G.; Giebels, B.; Giglietto, N.; Giordano, F.; Glanzman, T.; Godfrey, G.; A. Grenier, I.; Grondin, M.-H.; E. Grove, J.; Guillemot, L.; Guiriec, S.; Hadasch, D.; K. Harding, A.; Hays, E.; Hobbs, G.; Horan, D.; E. Hughes, R.; S. Jackson, M.; Johannesson, G.; S. Johnson, A.; J. Johnson, T.; N. Johnson, W.; Kamae, T.; Katagiri, H.; Kataoka, J.; Kawai, N.; Kerr, M.; Knodlseder, J.; Kuss, M.; Lande, J.; Latronico, L.; Lee, S.-H.; Lemoine-Goumard, M.; Llena Garde, M.; Longo, F.; Loparco, F.; Lott, B.; N. Lovellette, M.; Lubrano, P.; Makeev, A.; N. Manchester, R.; Marelli, M.; N. Mazziotta, M.; Mcconville, W.; E. Mcenery, J.; Mcglynn, S.; Meurer, C.; F. Michelson, P.; Mitthumsiri, W.; Mizuno, T.; A. Moiseev, A.; Monte, C.; E. Monzani, M.; Morselli, A.; V. Moskalenko, I.; Murgia, S.; Nakamori, T.; L. Nolan, P.; P. Norris, J.; Noutsos, A.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orlando, E.; F. Ormes, J.; Ozaki, M.; Paneque, D.; H. Panetta, J.; Parent, D.; Pelassa, V.; Pepe, M.; Pesce-Rollins, M.; Pierbattista, M.; Piron, F.; Porter, T.A.; Raino, S.; Rando, R.; S. Ray, P.; Razzano, M.; Reimer, A.; Reimer, O.; Reposeur, T.; Ritz, S.; S. Rochester, L.; Y. Rodriguez, A.; W. Romani, R.; Roth, M.; Ryde, F.; F.-W. Sadrozinski, H.; Sander, A.; M. Saz Parkinson, P.; Sgro, C.; J. Siskind, E.; Smith, David Stanley; D. Smith, P.; Spandre, G.; Spinelli, P.; Starck, Jean-Luc; S. Strickman, M.; J. Suson, D.; Takahashi, H.; Takahashi, T.; Tanaka, T.; B. Thayer, J.; G. Thayer, J.; J. Thompson, D.; Tibaldo, L.; F. Torres, D.; Tosti, G.; Tramacere, A.; L. Usher, T.; Van Etten, A.; Vasileiou, V.; Venter, C.; Vilchez, N.; Vitale, V.; P. Waite, A.; Wang, P.; Watters, K.; Weltevrede, P.; L. Winer, B.; S. Wood, K.; Ylinen, T.; Ziegler, M.
    35 pages, 12 figures, accepted for publication in Astrophysical Journal

  10. Detection of the energetic pulsar PSR B1509-58 and its pulsar wind nebula in MSH 15-52 using the Fermi-Large Area Telescope

    A. Abdo, A.; Ackermann, Markus; Ajello, Marco; Allafort, A.; Asano, K.; Baldini, Luca; Ballet, J.; Barbiellini, Guido; G. Baring, M.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Berenji, B.; D. Blandford, R.; D. Bloom, E.; Bonamente, E.; W. Borgland, A.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; Buson, S.; A. Caliandro, G.; A. Cameron, R.; Camilo, F.; Caraveo, P. A.; Carrigan, S.; M. Casandjian, J.; Cecchi, C.; Celik, O.; Chekhtman, A.; C. Cheung, C.; Chiang, J.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Conrad, J.; R. Den Hartog, P.; D. Dermer, C.; De Luca, A.; De Palma, F.; Dormody, M.; Do Couto E Silva, E.; S. Drell, P.; Dubois, R.; Dumora, D.; Farnier, C.; Favuzzi, C.; J. Fegan, S.; C. Ferrara, E.; B. Focke, W.; Frailis, M.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gehrels, N.; Germani, S.; Giglietto, N.; Giordano, F.; Glanzman, T.; Godfrey, G.; V. Gotthelf, E.; A. Grenier, I.; Grondin, M.-H.; E. Grove, J.; Guillemot, L.; Guiriec, S.; Hanabata, Y.; K. Harding, A.; Hays, E.; Hobbs, G.; Horan, D.; E. Hughes, R.; J'Ohannesson, G.; S. Johnson, A.; J. Johnson, T.; N. Johnson, W.; Johnston, S.; Kamae, T.; Kanai, Y.; Kanbach, G.; Katagiri, H.; Kataoka, J.; Kawai, N.; Keith, M.; Kerr, M.; Knodlseder, J.; Kuss, M.; Lande, J.; Latronico, L.; Lemoine-Goumard, M.; Llena Garde, M.; Longo, F.; Loparco, F.; Lott, B.; N. Lovellette, M.; Lubrano, P.; Makeev, A.; N. Manchester, R.; Marelli, M.; N. Mazziotta, M.; E. Mcenery, J.; F. Michelson, P.; Mitthumsiri, W.; Mizuno, T.; A. Moiseev, A.; Monte, C.; E. Monzani, M.; Morselli, A.; V. Moskalenko, I.; Murgia, S.; Nakamori, T.; L. Nolan, P.; P. Norris, J.; Nuss, E.; Ohno, M.; Ohsugi, T.; Omodei, N.; Orlando, E.; F. Ormes, J.; Paneque, D.; H. Panetta, J.; Parent, D.; Pelassa, V.; Pepe, M.; Pesce-Rollins, M.; Piron, F.; Porter, T.A.; Raino, S.; Rando, R.; Razzano, M.; Rea, N.; Reimer, A.; Reimer, O.; Reposeur, T.; Y. Rodriguez, A.; W. Romani, R.; Roth, M.; Ryde, F.; F.-W. Sadrozinski, H.; Sander, A.; M. Saz Parkinson, P.; Sgr'O, C.; J. Siskind, E.; Smith, David Stanley; D. Smith, P.; Spandre, G.; Spinelli, P.; Starck, Jean-Luc; S. Strickman, M.; J. Suson, D.; Takahashi, H.; Takahashi, T.; Tanaka, T.; B. Thayer, J.; G. Thayer, J.; J. Thompson, D.; E. Thorsett, S.; Tibaldo, L.; F. Torres, D.; Tosti, G.; Tramacere, A.; Uchiyama, Y.; L. Usher, T.; Vasileiou, V.; Venter, C.; Vilchez, N.; Vitale, V.; P. Waite, A.; Wang, P.; Weltevrede, P.; L. Winer, B.; S. Wood, K.; Yang, Z.; Ylinen, T.; Ziegler, M.
    14 pages, 6 figures, accepted for publication by ApJ

  11. Fermi LAT observations of the Geminga pulsar

    A. Abdo, A.; Ackermann, Markus; Ajello, Marco; Baldini, Luca; Ballet, J.; Barbiellini, Guido; Bastieri, D.; M. Baughman, B.; Bechtol, K.; Bellazzini, R.; Berenji, B.; F. Bignami, G.; D. Blandford, R.; D. Bloom, E.; Bonamente, E.; W. Borgland, A.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; H. Burnett, T.; A. Caliandro, G.; A. Cameron, R.; Caraveo, P. A.; M. Casandjian, J.; Cecchi, C.; Celik, O.; Charles, E.; Chekhtman, A.; C. Cheung, C.; Chiang, J.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Conrad, J.; D. Dermer, C.; De Palma, F.; Dormody, M.; Do Couto E Silva, E.; S. Drell, P.; Dubois, R.; Dumora, D.; Edmonds, Y.; Farnier, C.; Favuzzi, C.; J. Fegan, S.; B. Focke, W.; Fortin, P.; Frailis, M.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Gehrels, N.; Germani, S.; Giavitto, G.; Giglietto, N.; Giordano, F.; Glanzman, T.; Godfrey, G.; A. Grenier, I.; Grondin, M.-H.; E. Grove, J.; Guillemot, L.; Guiriec, S.; Hadasch, D.; K. Harding, A.; Hays, E.; E. Hughes, R.; Johannesson, G.; S. Johnson, A.; J. Johnson, T.; N. Johnson, W.; Kamae, T.; Katagiri, H.; Kataoka, J.; Kawai, N.; Kerr, M.; Knodlseder, J.; Kuss, M.; Lande, J.; Latronico, L.; Lemoine-Goumard, M.; Longo, F.; Loparco, F.; Lott, B.; N. Lovellette, M.; Lubrano, P.; Makeev, A.; Marelli, M.; N. Mazziotta, M.; E. Mcenery, J.; Meurer, C.; F. Michelson, P.; Mitthumsiri, W.; Mizuno, T.; A. Moiseev, A.; Monte, C.; E. Monzani, M.; Morselli, A.; V. Moskalenko, I.; Murgia, S.; L. Nolan, P.; P. Norris, J.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orlando, E.; F. Ormes, J.; Ozaki, M.; Paneque, D.; H. Panetta, J.; Parent, D.; Pelassa, V.; Pepe, M.; Pesce-Rollins, M.; Piron, F.; Porter, T.A.; Raino, S.; Rando, R.; S. Ray, P.; Razzano, M.; Reimer, A.; Reimer, O.; Reposeur, T.; S. Rochester, L.; Y. Rodriguez, A.; W. Romani, R.; Roth, M.; Ryde, F.; F.-W. Sadrozinski, H.; Sander, A.; M. Saz Parkinson, P.; D. Scargle, J.; Sgro, C.; J. Siskind, E.; Smith, David Stanley; D. Smith, P.; Spandre, G.; Spinelli, P.; S. Strickman, M.; J. Suson, D.; Takahashi, H.; Takahashi, T.; Tanaka, T.; B. Thayer, J.; G. Thayer, J.; J. Thompson, D.; Tibaldo, L.; F. Torres, D.; Tosti, G.; Tramacere, A.; L. Usher, T.; Van Etten, A.; Vasileiou, V.; Venter, C.; Vilchez, N.; Vitale, V.; P. Waite, A.; Wang, P.; Watters, K.; L. Winer, B.; S. Wood, K.; Ylinen, T.; Ziegler, M.
    32 pages, 12 figures, 3 tables. Accepted for publication in The Astrophysical Journal. Corresponding authors: Denis Dumora (dumora@cenbg.in2p3.fr), Fabio Gargano (Fabio.Gargano@ba.infn.it), Massimiliano Razzano (massimiliano.razzano@pi.infn.it)

  12. Constraints on the Galactic Population of TEV Pulsar Wind Nebulae Using Fermi Large Area Telescope Observations

    Acero, Fabio; Ackermann, Markus; Ajello, Marco; Allafort, A.; Baldini, Luca; Ballet, J.; Barbiellini, Guido; Bastieri, D.; Bechtol, K.; Bellazzini, R.; D. Blandford, R.; D. Bloom, E.; Bonamente, E.; Bottacini, E.; J. Brandt, T.; Bregeon, J.; Brigida, M.; Bruel, P.; Buehler, R.; A. Caliandro, G.; A. Cameron, R.; Caraveo, P. A.; Cecchi, C.; Charles, E.; C.G. Chaves, R.; Chekhtman, A.; Chiaro, G.; Cohen-Tanugi, J.; Conrad, J.; Dalton, M.; D'Ammando, F.; De Palma, F.; D. Dermer, C.; Di Venere, L.; Do Couto E Silva, E.; S. Drell, P.; Drlica-Wagner, A.; Falletti, L.; Favuzzi, C.; J. Fegan, S.; C. Ferrara, E.; B. Focke, W.; Franckowiak, A.; Fukazawa, Y.; Funk, S.; Gargano, F.; Gasparrini, D.; Giglietto, N.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Grondin, M.-H.; E. Grove, J.; Guiriec, S.; Hadasch, D.; Hanabata, Y.; K. Harding, A.; Hayashida, M.; Hayashi, K.; Hays, E.; Horan, D.; S. Jackson, M.; Jogler, T.; Kamae, T.; Kerr, M.; Lande, J.; Larsson, S.; Latronico, L.; Lemoine-Goumard, M.; Longo, F.; Loparco, F.; N. Lovellette, M.; Lubrano, P.; Marelli, M.; Massaro, F.; Mayer, M.; Maziotta, M.N.; Mehault, J.; Mitthumsiri, W.; E. Monzani, M.; Morselli, A.; V. Moskalenko, I.; Murgia, S.; Nakamori, T.; Okumura, A.; Orienti, M.; Orlando, E.; Paneque, D.; H. Panetta, J.; S. Perkins, J.; Pesce-Rollins, M.; Piron, F.; Pivato, G.; Porter, T.A.; Raino, S.; Rando, R.; Razzano, M.; Reposeur, T.; Roth, M.; Rousseau, R.; M. Saz Parkinson, P.; Schulz, A.; Sgro, C.; Spandre, G.; Spinelli, P.; Takahashi, H.; Takeuchi, Y.; G. Thayer, J.; B. Thayer, J.; J. Thompson, D.; Tibaldo, L.; Tibolla, O.; Tinivella, M.; F. Torres, D.; Tosti, G.; Uchiyama, Y.; Vandenbroucke, J.; Vasileiou, V.; Vianello, G.; Vitale, V.; Werner, M.; Yang, Z.
    Pulsar wind nebulae (PWNe) have been established as the most populous class of TeV gamma-ray emitters. Since launch, the Fermi Large Area Telescope (LAT)identified five high-energy (100MeV

  13. Vainshtein Screening in Scalar-Tensor Theories before and after GW170817: Constraints on Theories beyond Horndeski

    Dima, Alexandru; Vernizzi, Filippo
    Screening mechanisms are essential features of dark energy models mediating a fifth force on large scales. We study the regime of strong scalar field nonlinearities, known as Vainshtein screening, in the most general scalar-tensor theories propagating a single scalar degree of freedom. We first develop an effective approach to parameterize cosmological perturbations beyond linear order for these theories. In the quasi-static limit, the full nonlinear effective Lagrangian contains six independent terms, one of which starts at cubic order in perturbations. We compute the two gravitational potentials around a spherical body. Outside and near the body, screening reproduces standard gravity, with...

  14. Constraining Lorentz Invariance Violation Using the Crab Pulsar Emission Observed up to TeV Energies by MAGIC

    Barrio Uña, Juan Abel; Bonnefoy, Simon; Contreras González, José Luis; Domínguez Díaz, Alberto; Fidaldo, David Friedrich Contreras; Fonseca González, Mª Victoria; López Moya, Marcos; Nievas Rosillo, Miguel; Ahnen, M.L.; Ansoldi, S.; Otros, ...
    Spontaneous breaking of Lorentz symmetry at energies on the order of the Planck energy or lower is predicted by many quantum gravity theories, implying non-trivial dispersion relations for the photon in vacuum. Consequently, gamma-rays of different energies, emitted simultaneously from astrophysical sources, could accumulate measurable differences in their time of flight until they reach the Earth. Such tests have been carried out in the past using fast variations of gamma-ray flux from pulsars, and more recently from active galactic nuclei and gamma-ray bursts. We present new constraints studying the gamma-ray emission of the galactic Crab Pulsar, recently observed up to...

  15. Observation of the black widow B1957+20 millisecond pulsar binary system with the MAGIC telescopes

    Barrio Uña, Juan Abel; Bonnefoy, Simon; Contreras González, José Luis; Domínguez Díaz, Alberto; Fidalgo, David Friedrich Carreto; Fonseca González, Mª Victoria; López Moya, Marcos; Nievas Rosillo, Miguel; Ahnen, L.M.; Ansoldi, S.; Otros, ...
    Spontaneous breaking of Lorentz symmetry at energies on the order of the Planck energy or lower is predicted by many quantum gravity theories, implying non-trivial dispersion relations for the photon in vacuum. Consequently, gamma-rays of different energies, emitted simultaneously from astrophysical sources, could accumulate measurable differences in their time of flight until they reach the Earth. Such tests have been carried out in the past using fast variations of gamma-ray flux from pulsars, and more recently from active galactic nuclei and gamma-ray bursts. We present new constraints studying the gamma-ray emission of the galactic Crab Pulsar, recently observed up to...

  16. Observation of the black widow B1957+20 millisecond pulsar binary system with the MAGIC telescopes

    Barrio Uña, Juan Abel; Bonnefoy, Simon; Contreras González, José Luis; Domínguez Díaz, Alberto; Fidalgo, David Friedrich Carreto; Fonseca González, Mª Victoria; López Moya, Marcos; Nievas Rosillo, Miguel; Ahnen, L.M.; Ansoldi, S.; Otros, ...
    Spontaneous breaking of Lorentz symmetry at energies on the order of the Planck energy or lower is predicted by many quantum gravity theories, implying non-trivial dispersion relations for the photon in vacuum. Consequently, gamma-rays of different energies, emitted simultaneously from astrophysical sources, could accumulate measurable differences in their time of flight until they reach the Earth. Such tests have been carried out in the past using fast variations of gamma-ray flux from pulsars, and more recently from active galactic nuclei and gamma-ray bursts. We present new constraints studying the gamma-ray emission of the galactic Crab Pulsar, recently observed up to...

  17. Millisecond pulsar origin of the Galactic center excess and extended gamma-ray emission from Andromeda -- a closer look

    Eckner, C.; Di Mauro, M.; Hou, X.; Martin, P.; Mirabal, N.; Petrovic, J.; Prodanovic, T.; Serpico, P.; Vandenbrouck, J.; Winter, M.; Zaharijas, G.
    A new measurement of a spatially extended gamma-ray signal from the center ofthe Andromeda galaxy (M31) has been recently published by the Fermi-LATcollaboration, reporting that the emission broadly resembles the so-calledGalactic center excess (GCE) of the Milky Way (MW). At the same time, evidenceis accumulating on a millisecond pulsar (MSPs) origin for the GCE. Theseelements prompt us to compare the mentioned observations with what is, perhaps,the simplest model for an MSP population, solely obtained by rescaling of theMSP luminosity function determined in the local MW disk via the respectivestellar mass of the systems. It is remarkable that without free fittingparameters,...

  18. Millisecond pulsar origin of the Galactic center excess and extended gamma-ray emission from Andromeda -- a closer look

    Eckner, C.; Di Mauro, M.; Hou, X.; Martin, P.; Mirabal, N.; Petrovic, J.; Prodanovic, T.; Serpico, P.; Vandenbrouck, J.; Winter, M.; Zaharijas, G.
    A new measurement of a spatially extended gamma-ray signal from the center ofthe Andromeda galaxy (M31) has been recently published by the Fermi-LATcollaboration, reporting that the emission broadly resembles the so-calledGalactic center excess (GCE) of the Milky Way (MW). At the same time, evidenceis accumulating on a millisecond pulsar (MSPs) origin for the GCE. Theseelements prompt us to compare the mentioned observations with what is, perhaps,the simplest model for an MSP population, solely obtained by rescaling of theMSP luminosity function determined in the local MW disk via the respectivestellar mass of the systems. It is remarkable that without free fittingparameters,...

  19. A glitch in the millisecond pulsar J0613−0200

    McKee, J. W.; Janssen, G. H.; Stappers, B. W.; Lyne, A. G.; Caballero, R. N.; Lentati, L.; Desvignes, G.; Jessner, A.; Jordan, C. A.; Karuppusamy, R.; Kramer, M.; Cognard, Ismaël; Champion, D. J.; Graikou, E.; Lazarus, P.; Osłowski, S.; Perrodin, D.; Shaifullah, G.; Tiburzi, C.; Verbiest, J. P. W.
    International audience

  20. Discovery of Pulsed Gamma Rays from the Young Radio Pulsar PSR J1028-5819 with the Fermi Large Area Telescope

    Abdo, A.A.; Ackermann, Markus; B. Atwood, W.; Baldini, Luca; Ballet, J.; Barbiellini, Guido; G. Baring, M.; Bastieri, D.; M. Baughman, B.; Bechtol, K.; Bellazzini, R.; Berenji, B.; D. Bloom, E.; Bonamente, E.; W. Borgland, A.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; H. Burnett, T.; A. Caliandro, G.; A. Cameron, R.; Caraveo, P. A.; M. Casandjian, J.; Cecchi, C.; Charles, E.; Chekhtman, A.; C. Cheung, C.; Chiang, J.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; R. Cominsky, L.; Conrad, J.; D. Dermer, C.; De Angelis, A.; De Palma, F.; W. Digel, S.; Donato, D.; Dormody, M.; Do Couto E Silva, E.; S. Drell, P.; Dubois, R.; Dumora, D.; Edmonds, Y.; Farnier, C.; Favuzzi, C.; Fleury, P.; B. Focke, W.; Frailis, M.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Gehrels, N.; Germani, S.; Giebels, B.; Giglietto, N.; Giordano, F.; Glanzman, T.; Godfrey, G.; A. Grenier, I.; Grondin, M.-H.; E. Grove, J.; Guillemot, L.; Guiriec, S.; K. Harding, A.; Hayashida, M.; Hays, E.; E. Hughes, R.; Jóhannesson, G.; S. Johnson, A.; P. Johnson, R.; J. Johnson, T.; N. Johnson, W.; Johnston, S.; Kamae, T.; Katagiri, H.; Kataoka, J.; Kawai, N.; Kerr, M.; Knödlseder, J.; Komin, N.; Kramer, M.; Kuehn, F.; Kuss, M.; Latronico, L.; Lee, S.-H.; Lemoine-Goumard, M.; Longo, F.; Loparco, F.; Lott, B.; N. Lovellette, M.; Lubrano, P.; Makeev, A.; Marelli, M.; N. Mazziotta, M.; Mcconville, W.; E. Mcenery, J.; Meurer, C.; F. Michelson, P.; Mitthumsiri, W.; Mizuno, T.; A. Moiseev, A.; Monte, C.; E. Monzani, M.; Morselli, A.; V. Moskalenko, I.; Murgia, S.; L. Nolan, P.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orlando, E.; F. Ormes, J.; Paneque, D.; H. Panetta, J.; Parent, D.; Pepe, M.; Pesce-Rollins, M.; Piron, F.; Porter, T.A.; Rainò, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Reposeur, T.; Ritz, S.; S. Rochester, L.; Y. Rodriguez, A.; W. Romani, R.; Roth, M.; Ryde, F.; F.-W. Sadrozinski, H.; Sanchez, D.; Sander, A.; M. Saz Parkinson, P.; Sgrò, C.; J. Siskind, E.; Smith, David Stanley; D. Smith, P.; Spandre, G.; Spinelli, P.; Starck, Jean-Luc; S. Strickman, M.; J. Suson, D.; Tajima, H.; Takahashi, H.; Tanaka, T.; B. Thayer, J.; G. Thayer, J.; J. Thompson, D.; E. Thorsett, S.; Tibaldo, L.; F. Torres, D.; Tosti, G.; Tramacere, A.; Uchiyama, Y.; L. Usher, T.; Van Etten, A.; Vilchez, N.; Vitale, V.; P. Waite, A.; Watters, K.; S. Wood, K.; Ylinen, T.; Ziegler, M.; Hobbs, G.; Keith, M.; Manchester, R.N.; Weltevrede, P.
    Radio pulsar PSR J1028-5819 was recently discovered in a high-frequency search (at 3.1 GHz)in the error circle of the EGRET source 3EG J1027-5817. The spin-down power of this young pulsar is great enough to make it very likely the counterpart for the EGRET source. We report here the discovery of gamma-ray pulsations from PSR J1028-5819 in early observations by the Large Area Telescope (LAT) on the Fermi Gamma-Ray Space Telescope. The gamma-ray light curve shows two sharp peaks having phase separation of 0.460 +- 0.004, trailing the very narrow radio pulse by 0.200 +- 0.003 in phase, very similar to...

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