Browsing by Author "Bottacini, E."

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    Fermi-LAT Observations of LIGO/Virgo Event GW170817
    (IOP Publishing, 2018) Ajello, M.; Allafort, A.; Axelsson, M.; Baldini, L.; Barbiellini, G.; Baring, M.G.; Bastieri, D.; Bellazzini, R.; Berenji, B.; Bissaldi, E.; Blandford, R.D.; Bloom, E.D.; Bonino, R.; Bottacini, E.; Brandt, T.J.; Bregeon, J.; Bruel, P.; Buehler, R.; Burnett, T.H.; Buson, S.; Cameron, R.A.; Caputo, R.; Caraveo, P.A.; Casandjian, J.M.; Cavazzuti, E.; Chekhtman, A.; Cheung, C.C.; Chiang, J.; Chiaro, G.; Ciprini, S.; Cohen-Tanugi, J.; Cominsky, L.R.; Costantin, D.; Cuoco, A.; Cutini, S.; D’Ammando, F.; de Palma, F.; Di Lalla, N.; Di Mauro, M.; Di Venere, L.; Dubois, R.; Dumora, D.; Favuzzi, C.; Ferrara, E.C.; Franckowiak, A.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Giglietto, N.; Gill, R.; Giordano, F.; Giroletti, M.; Glanzman, T.; Granot, J.; Green, D.; Grenier, I.A.; Grondin, M.-H.; Guillemot, L.; Guiriec, S.; Harding, A.K.; Hays, E.; Horan, D.; Imazato, F.; Jóhannesson, G.; Kamae, T.; Kensei, S.; Kocevski, D.; Kuss, M.; La Mura, G.; Larsson, S.; Latronico, L.; Li, J.; Longo, F.; Loparco, F.; Lovellette, M.N.; Lubrano, P.; Magill, J.D.; Maldera, S.; Manfreda, A.; Mazziotta, M.N.; Michelson, P.F.; Mizuno, T.; Moiseev, A.A.; Monzani, M.E.; Moretti, E.; Morselli, A.; Moskalenko, I.V.; Negro, M.; Nuss, E.; Ojha, R.; Omodei, N.; Orlando, E.; Ormes, J.F.; Palatiello, M.; Paliya, V.S.; Paneque, D.; Persic, M.; Pesce-Rollins, M.; Petrosian, V.; Piron, F.; Porter, T.A.; Principe, G.; Racusin, J.L.; Rainò, S.; Rando, R.; Razzano, M.; Razzaque, S.; Reimer, A.; Reimer, O.; Ritz, S.; Rochester, L.S.; Ryde, F.; Parkinson, P.M. Saz; Sgrò, C.; Siskind, E.J.; Spada, F.; Spandre, G.; Spinelli, P.; Suson, D.J.; Tajima, H.; Takahashi, M.; Tak, D.; Thayer, J.G.; Thayer, J.B.; Torres, D.F.; Torresi, E.; Tosti, G.; Troja, E.; Valverde, J.; Venters, T.M.; Vianello, G.; Wood, K.; Yang, C.; Zaharijas, G.
    We present the Fermi Large Area Telescope (LAT) observations of the binary neutron star merger event GW170817 and the associated short gamma-ray burst (SGRB) GRB 170817A detected by the Fermi Gamma-ray Burst Monitor. The LAT was entering the South Atlantic Anomaly at the time of the LIGO/Virgo trigger (t GW) and therefore cannot place constraints on the existence of high-energy (E > 100 MeV) emission associated with the moment of binary coalescence. We focus instead on constraining high-energy emission on longer timescales. No candidate electromagnetic counterpart was detected by the LAT on timescales of minutes, hours, or days after the LIGO/Virgo detection. The resulting flux upper bound (at 95% C.L.) from the LAT is 4.5 × 10−10 erg cm−2 s−1 in the 0.1–1 GeV range covering a period from t GW + 1153 s to t GW + 2027 s. At the distance of GRB 170817A, this flux upper bound corresponds to a luminosity upper bound of 9.7 × 1043 erg s−1, which is five orders of magnitude less luminous than the only other LAT SGRB with known redshift, GRB 090510. We also discuss the prospects for LAT detection of electromagnetic counterparts to future gravitational-wave events from Advanced LIGO/Virgo in the context of GW170817/GRB 170817A.
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    PSR J2021+4026 in the Gamma Cygni Region: The First Variable y-Ray Pulsar Seen by the Fermi Lat
    (The American Astronomical Society, 2013) Baring, M.G.; Allafort, A.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.; Bonamente, E.; Bottacini, E.; Brandt, T.J.; Bregeon, J.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G.A.; Cameron, R.A.; Caraveo, P.A.; Cecchi, C.; Chaves, R.C.G.; Chekhtman, A.; Chiang, J.; Chiaro, G.; Ciprini, S.; Claus, R.; D'Ammando, F.; de Palma, F.; Digel, S.W.; Di Venere, L.; Drell, P.S.; Favuzzi, C.; Ferrara, E.C.; Franckowiak, A.; Fusco, P.; Gargano, F.; Gasparrini, D.; Giglietto, N.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Grenier, I.A.; Guiriec, S.; Hadasch, D.; Harding, A.K.; Hayashida, M.; Hayashi, K.; Hays, E.; Hewitt, J.; Hill, A.B.; Horan, D.; Hou, X.; Jogler, T.; Johnson, A.S.; Johnson, T.J.; Kerr, M.; Knödlseder, J.; Kuss, M.; Lande, J.; Larsson, S.; Latronico, L.; Lemoine-Goumard, M.; Lande, J.; Loparco, F.; Lubrano, P.; Malyshev, D.; Marelli, M.; Mayer, M.; Mazziotta, M.N.; Mehault, J.; Mizuno, T.; Monzani, M.E.; Morselli, A.; Murgia, S.; Nemmen, R.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orienti, M.; Orlando, E.; Paneque, D.; Pesce-Rollins, M.; Pierbattista, M.; Piron, F.; Pivato, G.; Porter, T.A.; Rainò, S.; Rando, R.; Ray, P.S.; Razzano, M.; Reimer, O.; Reposeur, T.; Romani, R.W.; Sartori, A.; Saz Parkinson, P.M.; Sgrò, C.; Siskind, E.J.; Smith, D.A.; Spinelli, P.; Strong, A.W.; Takahashi, H.; Thayer, J.B.; Thompson, D.J.; Tibaldo, L.; Tinivella, M.; Torres, D.F.; Tosti, G.; Uchiyama, Y.; Usher, T.L.; Vandenbroucke, J.; Vasileiou, V.; Venter, C.; Vianello, G.; Vitale, V.; Winer, B.L.; Wood, K.S.
    Long-term monitoring of PSR J2021+4026 in the heart of the Cygnus region with the Fermi Large Area Telescope unveiled a sudden decrease in flux above 100 MeV over a timescale shorter than a week. The "jump" was near MJD 55850 (2011 October 16), with the flux decreasing from (8.33 ± 0.08) × 10–10 erg cm–2 s–1 to (6.86 ± 0.13) × 10–10 erg cm–2 s–1. Simultaneously, the frequency spindown rate increased from (7.8 ± 0.1) × 10–13 Hz s–1 to (8.1 ± 0.1) × 10–13 Hz s–1. Significant (>5σ) changes in the pulse profile and marginal (<3σ) changes in the emission spectrum occurred at the same time. There is also evidence for a small, steady flux increase over the 3 yr preceding MJD 55850. This is the first observation at γ-ray energies of mode changes and intermittent behavior, observed at radio wavelengths for other pulsars. We argue that the change in pulsed γ-ray emission is due to a change in emission beaming and we speculate that it is precipitated by a shift in the magnetic field structure, leading to a change of either effective magnetic inclination or effective current.
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    The Second Fermi Large Area Telescope Catalog of Gamma-Ray Pulsars
    (The American Astronomical Society, 2013-10) Baring, M.G.; Abdo, A.A.; Ajello, M.; Allafort, A.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Belfiore, A.; Bellazzini, R.; Bhattacharyya, B.; Bissaldi, E.; Bloom, E.D.; Bonamente, E.; Bottacini, E.; Brandt, T.J.; Bregeon, J.; Brigida, M.; Bruel, P.; Buehler, R.; Burgay, M.; Burnett, T.H.; Busetto, G.; Buson, S.; Cameron, R.A.; Camilo, F.; Caraveo, P.A.; Casandjian, J.M.; Cecchi, C.; Çelik, Ö.; Charles, E.; Chaty, S.; Chaves, R.C.G.; Chekhtman, A.; Chen, A.W.; Chiang, J.; Chiaro, G.; Ciprini, S.; Claus, R.; Cognard, I.; Cohen-Tanugi, J.; Cominsky, L.R.; Conrad, J.; Cutini, S.; D'Ammando, F.; de Angelis, A.; DeCesar, M.E.; De Luca, A.; den Hartog, P.R.; de Palma, F.; Dermer, C.D.; Desvignes, G.; Digel, S.W.; Di Venere, L.; Drell, P.S.; Drlica-Wagner, A.; Dubois, R.; Dumora, D.; Espinoza, C.M.; Falletti, L.; Favuzzi, C.; Ferrara, E.C.; Focke, W.B.; Franckowiak, A.; Freire, P.C.C.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Germani, S.; Giglietto, N.; Giommi, P.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Gotthelf, E.V.; Grenier, I.A.; Grondin, M.-H.; Grove, J.E.; Guillemot, L.; Guiriec, S.; Hadasch, D.; Hanabata, Y.; Harding, A.K.; Hayashida, M.; Hays, E.; Hessels, J.; Hewitt, J.; Hill, A.B.; Horan, D.; Hou, X.; Hughes, R.E.; Jackson, M.S.; Janssen, G.H.; Jogler, T.; Jóhannesson, G.; Johnson, R.P.; Johnson, A.S.; Johnson, T.J.; Johnson, W.N.; Johnston, S.; Kamae, T.; Kataoka, J.; Keith, M.; Kerr, M.; Knӧdlseder, J.; Kramer, M.; Kuss, M.; Lande, J.; Larsson, S.; Latronico, L.; Lemoine-Goumard, M.; Longo, F.; Loparco, F.; Lovellette, M.N.; Lubrano, P.; Lyne, A.G.; Manchester, R.N.; Marelli, M.; Massaro, F.; Mayer, M.; Mazziotta, M.N.; McEnery, J.E.; McLaughlin, M.A.; Mehault, J.; Michelson, P.F.; Mignani, R.P.; Mitthumsiri, W.; Mizuno, T.; Moiseev, A.A.; Monzani, M.E.; Morselli, A.; Moskalenko, I.V.; Murgia, S.; Nakamori, T.; Nemmen, R.; Nuss, E.; Ohno, M.; Ohsugi, T.; Orienti, M.; Orlando, E.; Ormes, J.F.; Paneque, D.; Panetta, J.H.; Parent, D.; Perkins, J.S.; Pesce-Rollins, M.; Pierbattista, M.; Piron, F.; Pivato, G.; Pletsch, H.J.; Porter, T.A.; Possenti, A.; Rainò, S.; Rando, R.; Ransom, S.M.; Ray, P.S.; Razzano, M.; Rea, N.; Reimer, A.; Reimer, O.; Renault, N.; Reposeur, T.; Ritz, S.; Romani, R.W.; Roth, M.; Rousseau, R.; Roy, J.; Ruan, J.; Sartori, A.; Saz Parkinson, P.M.; Scargle, J.D.; Schulz, A.; Sgrò, C.; Shannon, R.; Siskind, E.J.; Smith, D.A.; Spandre, G.; Spinelli, P.; Stappers, B.W.; Strong, A.W.; Suson, D.J.; Takahashi, H.; Thayer, J.G.; Thayer, J.B.; Theureau, G.; Thompson, D.J.; Thorsett, S.E.; Tibaldo, L.; Tibolla, O.; Tinivella, M.; Torres, D.F.; Tosti, G.; Troja, E.; Uchiyama, Y.; Usher, T.L.; Vandenbroucke, J.; Vasileiou, V.; Venter, C.; Vianello, G.; Vitale, V.; Wang, N.; Weltevrede, P.; Winer, B.L.; Wolff, M.T.; Wood, D.L.; Wood, K.S.; Wood, M.; Yang, Z.
    This catalog summarizes 117 high-confidence 0.1 GeV gamma-ray pulsar detections using three years of data acquired by the Large Area Telescope (LAT) on the Fermi satellite. Half are neutron stars discovered using LAT data through periodicity searches in gamma-ray and radio data around LAT unassociated source positions. The 117 pulsars are evenly divided into three groups: millisecond pulsars, young radio-loud pulsars, and young radio-quiet pulsars. We characterize the pulse profiles and energy spectra and derive luminosities when distance information exists. Spectral analysis of the off-peak phase intervals indicates probable pulsar wind nebula emission for four pulsars, and off-peak magnetospheric emission for several young and millisecond pulsars.We compare the gammaray properties with those in the radio, optical, and X-ray bands.We provide flux limits for pulsars with no observed gamma-ray emission, highlighting a small number of gamma-faint, radio-loud pulsars. The large, varied gamma-ray pulsar sample constrains emission models. Fermiﾒs selection biases complement those of radio surveys, enhancing comparisons with predicted population distributions.