Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Japanese historical records of SNRs and SUZAKU observation of SN1006 2006/05/16 国宝「明月記」(冷泉家時雨亭文庫) One Millennium after SN 1006? @Hangzhou Hiroya Yamaguchi (Kyoto Univ., Japan) Katsuji Koyama (Kyoto Univ.) Junko Hiraga (RIKEN), Aya Bamba (RIKEN) My talk plan • The Japanese historical records of SN1006 and other supernova remnants. • Introduction of Japanese satellite “Suzaku”. • Report of the Suzaku observation of SN1006. • Summary Historical record of SNRs Ancient China and Japan Astronomical records (auroras, eclipse, shooting star and etc.) were frequently appeared after 7th century. The exchange between China and Japan was very active. 遣隋使 (Kenzuishi) The mission to China 煬帝 Yang Di Astronomical knowledge and thought 聖徳太子 Shotoku-taishi (assistance of emperor) In 12-13th century, Teika Fujiwara (Japanese noble and poet) collected the ancient astronomical records, and noted them in his diary “Meigetsuki(明月記)”. He started to write the diary when he was 19 years old, and continued for 56 years. In those days, diaries had the role of the records of the ceremony, political affairs, and disasters. 藤原定家 Teika Fujiwara (1162-1241) Unusual astronomical phenomena (supernovae, eclipses, comets, and shooting stars) were believed as the predictions of famines, epidemics, and floods. Japanese historical record of SNR “Meigetsuki” (This page was written in 11/8, 1230.) 8 7 6 5 4 3 2 1 Crab Nebula 「客星古現例」 the ancient samples of “guest stars”. Guest stars = comets, novae, and supernovae 3C58 SN1006 SN1006 一條院 寛弘三年 四月二日 葵酉 夜以降 騎官中 有大客星 如螢惑 光明動耀 連夜正見南方 或云 騎陣将軍星本体 増変光 Chandra image of SN1006 In the reign-period of Ichijo-In, April 2nd, 3rd year of Kanko (= May 1st, 1006), a great guest star appeared within the constellation “Kikan” 騎官 (kikan) (=Imperial Guards). It was very bright like Mars, and visible in the southern sky every night. One possibility was the star of “Kijin-Shogun” (= Chariots and General) suddenly lighten? 騎陣将軍 (Kijin-Shogun) Lupusκ Crab nebula 後冷泉院 天喜二年 四月中旬以降 丑時 客星觜参度 見東方 孛天関星 大如歳星 Chandra image of Crab In the reign-period of Goreizei-In, after the middle of April, 2nd year of Tenki (= May-June, 1054), a guest star appeared nearby “Shi” and “Shin” (= Orion) in eastern sky 天関 (Tenkan) at 2:00. It shined near to the Taurusζ star of “Tenkan”, and its size was comparable to Jupiter. 觜, 参 = Orion 3C58 高倉院 治承五年 六月廿五日 庚午 戌時 客星見北方 近王良 守伝舎星 Chandra image of 3C58 王良 (Oh-Ryo) Cassiopeiaβ 伝舎 (Densya) = Camelopardalis In the reign-period of Takakura-In, June 25th, 5th year of Jisyou (= August 7th, 1181), a guest star appeared in northern sky at 20:00. It was near to the star of “Oh-Ryo” (= real person’s name of ancient China) and “Densya”. “Meigetsuki” was designated as a national treasure in 2000. It is preserved by Reizei-ke(冷泉家), descendant of Teika Fujiwara. Kyoto Univ. Reizei-ke Kyoto Gyoen Very near ! (~2km) Kamo river Introduction of Suzaku Introduction of Suzaku The 5th Japanese X-ray astronomical satellite. It was launched on July 10th 2005. 朱雀 (Suzaku) Suzaku is “Red Chinese Phoenix”, the protector God of the South. The wall painting of Suzaku in “Kitora” tomb Instrument XRT (X-Ray Telescope) Large effective area 450cm2 @1.5keV per 1 unit XRT XIS (X-ray Imaging Spectrometer) Improved X-ray CCD with high efficiency and good energy resolution Low Background Energy band : 0.2-12keV HXD (Hard X-ray Detector) Wide energy band Si-PIN (8-50keV) & Scintillator (50-600keV) Non-imaging detector, but low background XIS HXD XIS 4 units 3 Front-illuminated (FI) CCD ‥ high efficiency for hard X-ray 1 Back-illuminated (BI) CCD ‥ high efficiency for soft X-ray XRT XRT FI CCD BI CCD DE PPU to DP MPU PPU Bonnet AE/TCE Base Sensor XIS Quantum Efficiency of XIS XIS Comparison of efficiency and energy resolutions O VIII Suzaku XIS-FI Suzaku XIS-BI O VII Ne IX Ne X Spectra of E0102-72 XIS Comparison of background levels BGD spectra normalized by solid angle of FOV and effective area Suzaku XIS-FI Suzaku XIS-BI XMM EPIC-MOS XMM EPIC-pn Suzaku observation of SN1006 Cosmic ray accelerator Koyama et al. (1995) discovered synchrotron X-ray from the shell of SN1006. → Indication of ~100TeV electrons SNRs are cosmic ray accelerator ! 10’ Unsolved problem ASCA image of SN1006 The environment of accelerating place ‥ Plasma temperature, density, and so on. Essential information to understand the acceleration mechanism. Temperature ‥ 0.1 - 1 keV Density ‥ 0.1 - 10 cm-3 We don’t know accurate value, nor positional dependence. Suzaku XIS-BI (high efficiency and good energy resolution) is the best instrument to resolve this problem ! Thermal X-ray from SNRs We can get the information of temperature and density from thermal X-ray spectrum of SNR ! Shock front of SNR heats the matter up to a temperature of a few keV (~107 K), and emits X-rays (bremsstrahlung and line emissions). Electron temperature ‥ the shape of the bremsstrahlung continuum Density ‥ the flux of the continuum and the line emissions Brems: I(ν) ∝ (hν)-0.4 exp(-hν/kTe)・nenpV Line: Iz∝ nenzV ne = electron density, np = proton density nz = ion density, V = volume of emission region Thermal X-ray from SNRs Ionization Oxygen ionization fraction vs. electron temp. He-like H-like Neutral He-like ion H-like ion Fully ionized 10 100 103 Electron temperature (eV) 1 104 Higher temperature Higher ionized state Higher density Non-equilibrium ionization (NEI) Oxygen ionization fraction vs. net (for kTe=1.5keV) At low density, Te ≠ Tz He-like H-like Neutral Fully ionized Ionization equilibrium requires ~103 years ! 106 107 108 109 net (cm-3 s) 1010 1011 1012 XIS image of SN1006 43.5ksec Suzaku observed SN1006 by 6pointing on 2005/9 and 2006/2. 62.4ksec 4 pointing on source 2 pointing for background Extract spectrum from whole northeast region. 59.1ksec 61.6ksec XIS-BI 0.3 - 5.5 keV image Spectra of whole NE region H-O He-O He-O band Non-thermal emission Black : XIS-BI Red : average of 3 XIS-FIs 3 - 5 keV band Successfully divided oxygen lines and synchrotron component ! Narrow band images of XIS-BI He-O line band 3 - 5 keV band Distributions of thermal plasma (line emission) and non-thermal electron (synchrotron emission) are different ! Narrow band images of XIS-BI NE rim of SN1006 He-O line band 3 - 5 keV band Easthern rim emits X-rays in the He-O band (soft thermal X-rays), and northern rim emits hard X-rays ?? Spectral analysis of NE region We divided NE region into 8x8 region, and extracted spectra from each square region. Northern rim Compared the fluxes of O lines and 3-5keV band. Used region: in the YELLOW frame Inner region Eastern rim He-O line vs. hard X-ray emission Northern rim Eastern rim Inner region Consistent with imaging analysis ! H-O line vs. hard X-ray emission Northern rim Similar distribution to He-O vs. hard X-ray Eastern rim Inner region Chandra image of SN1006 These regions are correspond to 2 Chandra filaments in NE shell. Northern rim Northern rim Inner region Eastern rim The first result: We distinguished the spectral properties of two filaments ! Eastern rim Chandra image with Suzaku FOV. Inner region Eastern rim Black: NH=1x1021cm-2 Red: NH=2x1021cm-2 Blue: NH=3x1021cm-2 H-O/He-O~0.2 in all regions ! Northern rim He-O High Density H-O More detailed analysis and discussion High Temp. kTe vs. net (for H-O/He-O=0.2) Line intensity: Eastern rim > Northern rim → Density: Eastern rim > Northern rim H-O/He-O ratio: Eastern rim = Northern rim → Temperature: Eastern rim < Northern rim More detailed analysis and discussion Non-thermal emission Γ~ 2.7 Higher energy electrons exist in Northern rim ? Emax ∝ V ∝ρ-1/5 Γ~ 3.1 Black: Northern rim Red: Eastern rim Low density → High shock speed → High acceleration efficiency Future work Quantitative decision of temperature, density, and maximum energy of accelerated electrons by spectral fitting with precise response of XIS. Summary • We observed SN1006 with Suzaku. • We succeed to divide two oxygen lines from continuum spectrum. • We discovered positional dependence of line intensities in the NE region of SN1006. • E rim = High density and low temperature, N rim = low density and high temperature? HXD Comparison of background levels Counts sec-1 keV-1 cm-2 BGD spectra normalized by effective area 1Crab BeppoSAX-PDS RXTE-PCA/HEXTE Suzaku HXD-PIN/GSO 10 Energy (keV) 100 500 Discussions North rim East rim Inner region Line weak intense middle Non-thermal intense hard intense soft weak Density of ISM ? ‥ Line intensity ∝ ρ2 ‥ Radius ∝ ρ-1/3 rnorth > reast (Rothenflug et al. 2004) VLA (1518MHz) image of SN1006