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Stephen C.-Y. Ng HKU

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Outline What are pulsar wind nebulae? Physical properties and evolution Why study PWNe? Common TeV sources, particle accelerators Multiwavelength observations of PWNe Broadband SED Surprise from Fermi: Crab flaring FAN 4, Jul 9 2013Stephen Ng

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Pulsar Winds Where does pulsar rotational energy go? >10 35 erg/s < 10% in radiation (mostly -rays) > 90% in pulsar winds FAN 4, Jul 9 2013Stephen Ng Credit: D. Page

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Pulsar Wind FAN 4, Jul 9 2013Stephen Ng Credit: CXC/D.Berry

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Termination Shock FAN 4, Jul 9 2013Stephen Ng Termination shock c c/3 Free -streaming pulsar wind Ejecta/ISM Credit: P. Slane Shocked pulsar wind Pulsar wind nebulae: broadband synchrotron bubbles (see reviews by Gaensler & Slane 2006; Cheng 2009) Gaensler & Slane (2006)

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Pulsar Wind Nebula Stephen NgFAN 4, Jul 9 2013

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NASA/CXC/ESA/2MASS/NRAO Broadband Emission FAN 4, Jul 9 2013Stephen Ng

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Crab Nebula FAN 4, Jul 9 2013 Abdo et al. (2010) Synchrotron IC Fermi LAT

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Why study PWNe? Relativistic shock physics Cosmic ray acceleration Important TeV sources FAN 4, Jul 9 2013Stephen Ng Sironi & Spitkovsky (2011)

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Why study PWNe? Relativistic shock physics Cosmic ray acceleration Important TeV sources FAN 4, Jul 9 2013Stephen Ng Aguilar et al. (2013) e + excess: dark matter decay? Or pulsars/PWNe?

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Why study PWNe Relativistic shock physics Cosmic ray acceleration Important TeV sources FAN 4, Jul 9 2013Stephen Ng 35 TeV PWNe: largest group, ~1/4 identified TeV sources

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PWN Evolution FAN 4, Jul 9 2013Stephen Ng van der Swaluw et al. (2003)

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Free Expansion FAN 4, Jul 9 2013Stephen Ng van der Swaluw et al. (2003)

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Axisymmetric Structure FAN 4, Jul 9 2013Stephen Ng CXC/D.BerryLyubarsky (2002)

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Torus+Jet Kes 75 Gotthelf+00; Ng+ 08 Lu+02; Temim+10 G54.1+0.3 Slane+02; 04 3C 58 Weisskopf+00; Hester+02 Crab Pavlov+01; Helfand+01 Vela

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Torus Modelling CrabVelaB1706-44 J2221+6114 J1930+1852 / G54.1+0.3 B0540-69J0205+6449 / 3C58 J0537-6910 / N157B B1800-21 J2021+3651 J1833+1034 / G21.5-0.9 J1124-5916 / G292.0+1.8 Stephen Ng Ng & Romani (2004; 2008) FAN 4, Jul 9 2013

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Hand of God: FAN 4, Jul 9 2013Stephen Ng Aharonian et al. (2005) HESS TeV MSH 1552 / PSR B150958 NASA/CXC/SAO/Slane et al. Chandra

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Hand of God: FAN 4, Jul 9 2013Stephen Ng MSH 1552 / PSR B150958 NASA/CXC/SAO/Slane et al. Chandra Radio Ng et al. (2013,in prep.)

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Free Expansion FAN 4, Jul 9 2013Stephen Ng van der Swaluw et al. (2003)

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Reverse-Shock Interaction FAN 4, Jul 9 2013Stephen Ng van der Swaluw et al. (2003)

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NASA/PSU/Pavlov Vela X Stephen Ng Aharonian et al. (2006) TeV Abdo et al. (2010) Fermi Mattana et al. (2011) NASA/SAO/CXC X-rays

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G327.11.1 FAN 4, Jul 9 2013Stephen Ng Acero et al. (2012) TeV Temim et al. (2009) Radio + X-ray Ng et al. (2013, in prep.) Radio preliminary No Fermi Detection

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Bow Shock FAN 4, Jul 9 2013Stephen Ng van der Swaluw et al. (2003)

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Bow Shocks Supersonic motion in the ISM bow shocks Stephen Ng CXC/Weiss ISM ram pressure Pulsar wind pressure FAN 4, Jul 9 2013

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The Frying Pan G315.90.0 / PSR J14375959 ~ 2000 km/s Longest pulsar tail > 20pc FAN 4, Jul 9 2013Stephen Ng Ng et al. (2012 )

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PSR J15095850 / G319.90.7 Ng et al. (2010) FAN 4, Jul 9 2013Stephen Ng Kargaltsev et al. (2008); Ng et al. (2010) X-ray + Radio Radio

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Multiwavelength Studies FAN 4, Jul 9 2013Stephen Ng Crab PWN Abdo et al. (2010) Synchrotron IC

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Multiwavelength Studies FAN 4, Jul 9 2013Stephen Ng Abdo et al. (2010) MSH 15 52 / PSR B1509 58

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1D Modelling FAN 4, Jul 9 2013Stephen Ng Gelfand et al. (2009)

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Time Variability FAN 4, Jul 9 2013Stephen Ng

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Crab Nebula: A Standard Candle? Cospar 7/16/2012Stephen Ng Wilson-Hodge et al. (2011)

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Time Variability FAN 4, Jul 9 2013Stephen Ng NASA/ASU/Hester

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Crab PWN FAN 4, Jul 9 2013 NASA/ASU/Hester Stephen Ng

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Vela Jet FAN 4, Jul 9 2013Stephen Ng NASA/CXC/PSU/Pavlov et al.

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Vela Jet FAN 4, Jul 9 2013Stephen Ng Durant et al. (2013)

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Ng et al. (2008); Livingstone, Ng et al. (2011) PSR J1846 0258 / Kes 75 FAN 4, Jul 9 2013 200020062009 Stephen Ng

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Crab -ray Flares FAN 4, Jul 9 2013Stephen Ng

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Crab Flares FAN 4, Jul 9 2013Stephen Ng Striani et al. (2013)

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2013 Mar Flare FAN 4, Jul 9 2013Stephen Ng Striani et al. (2013); Tavani et al. (2013)

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Flare Spectrum FAN 4, Jul 9 2013Stephen Ng Striani et al. (2013)

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Flare Spectrum FAN 4, Jul 9 2013Stephen Ng Weisskopf et al. (2013)

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Summary What are pulsar wind nebulae? Physical properties and evolution Why study PWNe? Common TeV sources, particle accelerators Multiwavelength observations of PWNe Broadband SED Surprise from Fermi: Crab flaring FAN 4, Jul 9 2013Stephen Ng