CANAGAROO-II PSR B1509-58 Yamagata Univ. N.Sakamoto , S.Gunji Tokai Univ. Y.Miyashita , K.Nishijima , J.Kushida and CANGAROO Team

A.K.Harding(2002), astro-ph/0208421 High-Energy Pulsars A.K.Harding(2002), astro-ph/0208421 EGRET Gamma-ray pulsars X-ray & Radio pulsed emission detected X-ray pulsed emission detected

Gamma-Ray Pulsars •Geminga(J0633+1746) 1.0*10^35 Unable to observe E / 4πd^2 (arbitrary unit) •Crab(B0531+21) 1.0*10^37 Detected •J2229+6114 3.0*10^36 Unable to observe •Vela(B0833-45) 2.2*10^36 Detected •Geminga(J0633+1746) 1.0*10^35 Unable to observe •B1509-58 7.4*10^34 Marginally Detected with 3.8m and ? with 10m •B1706-44 5.0*10^34 Detected •B1951+32 5.0*10^34 Unable to observe •B0656+14 3.9*10^34 ? •B1046-58 2.0*10^34 ? •B1055-52 1.0*10^33 Upper limit

Timing Analysis of the pulsar Polar Cap Model The emission from near the magnetic pole. Because strong magnetic fields cause pair creation for high energy gamma rays, gamma rays more than 10 GeV will not be emitted. Outer Gap Model The emission from near the light cylinder. Because the magnetic fields are not so strong near the light cylinder, gamma rays up to 100 GeV would be emitted. The threshold of ~100 GeV is necessary to distinguish the two models.

PSR B1509-58 and SNR MSH15-52 Source Position(J2000) (RA , Dec)=(228.48°, - 59.14°) Period : 150.0 ms Period Derivative : 1540.0×10-15s s-1 Age : 1700 yr 　　SNR MSH15-52 Distance : 4.4 kpc 0.6 ° × 0.5 ° Age : 6 - 21 ×103 yr Magnetic field : 5 ~ 10µG Over 10 times weaker than Crab Chandra（2000） 　18´ × 37.5´ Over 10 times wider than Crab

PSR B1509-58 spectrum L.Kuiper et al.,A&A(1999) pulsed pulsed? break COMPTEL pulsed WELCOME pulsed? RXTE EGRET OSSE break @10-30Mev Ginga unpulsed CANGAROO ASCA GeV,TeV region is Interesting!

Observation with CANGAROO-II 2002 On source Off source May 20 h 56 m 17 h 41 m June 8 h 05 m 6 h 15 m July 5 h 48 m 7 h 12 m Total 34 h 49 m 31 h 08 m Off set : 0.55 deg(~ 11 May), 0.40 deg(13 May ~) Maximum Elevation Angle : 61.95 deg

Imaging Atmospheric Cerenkov Technique (IACT) Fitting the image to the ellipse shape Investigating the alpha distribution for the air showers, we can recognize whether the object emits gamma ray or not. gamma proton

Alpha Plot PRELIMINARY Low Energy Medium Energy High Energy sumADC = 4000 - 9500 9500 - 21600 21600 - - 1.1σ(α<15) 4.1σ(α<15) - 0.9σ(α<15) PRELIMINARY

0) Applying more advanced method of data selection, we will improve the quality of the alpha plot. 1) It is important to identify where the gamma rays are emitted from. So we will carry out the data analysis for imaging. 2) Now stereo observation is ready ! So we want to observe PSR B1509-58 with two telescopes. For such observation, there are two merits ; better angular resolution and reduction of the background. They enable us to investigate the morphology in detail and the pulsation. 3) In the future, if we can construct a telescope with larger area, the energy threshold will become lower. It will enable us to distinguish two theoretical models for pulsars; polar cap model and outer gap model.