Kazumasa KAWATA ICRR, The University of Tokyo Interplanetary Coronal Mass Ejection and the Sun's Shadow Observed by the Tibet Air Shower Array ICRC2017 14 July, 2017 @Busan, Korea. For the Tibet AS g Collaboration 1
the Sun’s Shadow Observed by The Tibet AS g Collaboration � M.Amenomori(a), X.J.Bi(b), D.Chen(c), T.L.Chen(d), W.Y.Chen(b), S.W.Cui(e), Danzengluobu(d), L.K.Ding(b), C.F.Feng(f), Zhaoyang Feng(b), Z.Y.Feng(g), Q.B.Gou(b), Y.Q.Guo(b), H.H.He(b), Z.T.He(e), K.Hibino(h), N.Hotta(i), HaibingHu(d), H.B.Hu(b), J.Huang(b), H.Y.Jia(g), L.Jiang(b), F.Kajino(j), K.Kasahara(k), Y.Katayose(l), C.Kato(m), K.Kawata(n), M.Kozai(o,m), Labaciren(d), G.M.Le(p), A.F.Li(q,f,b), H.J.Li(d), W.J.Li(b,g), C.Liu(b), J.S.Liu(b), M.Y.Liu(d), H.Lu(b), X.R.Meng(d), T.Miyazaki(m), K.Mizutani(k,r), K.Munakata(m), T.Nakajima(m), Y.Nakamura(m), H.Nanjo(a), M.Nishizawa(s), T.Niwa(m), M.Ohnishi(n), I.Ohta(t), S.Ozawa(k), X.L.Qian(f,b), X.B.Qu(u), T.Saito(v), T.Y.Saito(w), M.Sakata(j), T.K.Sako(x,n), J.Shao(b,f), M.Shibata(l), A.Shiomi(y), T.Shirai(h), H.Sugimoto(z), M.Takita(n), Y.H.Tan(b), N.Tateyama(h), S.Torii(k), H.Tsuchiya(A), S.Udo(h), H.Wang(b), H.R.Wu(b), L.Xue(f), Y.Yamamoto(j), K.Yamauchi(l), Z.Yang(b), A.F.Yuan(d), T.Yuda(n), L.M.Zhai(c), H.M.Zhang(b), J.L.Zhang(b), X.Y.Zhang(f), Y.Zhang(b), YiZhang(b), Ying Zhang(b), Zhaxisangzhu(d) and X.X.Zhou(g) (a)Department of Physics, Hirosaki Univ., Japan (o)ISAS/JAXA, Japan (b)Key Laboratory of Particle Astrophysics, IHEP, CAS, China (p)National Center for Space Weather, (c)National Astronomical Observatories, CAS, China China Meteorological Administration, China (d)Department of Mathematics and Physics, Tibet Univ., China (q)School of Information Science and Engineering, (e)Department of Physics, Hebei Normal Univ., China Shandong Agriculture Univ., China (f)Department of Physics, Shandong Univ., China (r)Saitama Univ., Japan (g)Institute of Modern Physics, SouthWest Jiaotong Univ., China (s)National Institute of Informatics, Japan (h)Faculty of Engineering, Kanagawa Univ., Japan (t)Sakushin Gakuin Univ., Japan (i)Faculty of Education, Utsunomiya Univ., Japan (u)College of Science, China Univ. of Petroleum, China (j)Department of Physics, Konan Univ., Japan (v)Tokyo Metropolitan College of Industrial Technology, Japan (k)Research Institute for Science and Engineering, (w)Max-Planck-Institut fur Physik, Deutschland Waseda Univ., Japan (x)Escuela de Ciencias Fisicas Nanotechnologia, Yachay Tech, Ecuador (l)Faculty of Engineering, Yokohama National Univ., Japan (y)College of Industrial Technology, Nihon Univ., Japan (m)Department of Physics, Shinshu Univ., Japan (z)Shonan Institute of Technology, Japan (n)ICRR, The Univ. of Tokyo, Japan (A)Japan Atomic Energy Agency, Japan
shadow on the earth. Photosphere: TeV proton --> Charged particle Lamor radius models @1AU (Zeeman effect) Sun blocks VHE cosmic rays, and cast the cosmic-ray Optical observation Sun Shadow Satellite Earth Sun ～7.4AU (B=30 µ G near the earth) ～0.16R ☉ (B=300mG near the sun) à Probe of the solar MFs ! 3
Sun Shadow Observation map centered at the Sun varying in a correlation deficit and location In this map, we analyze Angular resolution(0.9 o ) Optical disk size(0.26 o ) Maximum -4%. Deficit ratio to B.G. (GSE coordinate) ４ o x４ o Cosmic ray density with the solar magnetic field West<- ->east North<- 2009 GSE latitude (deg.) Sun disk ->South Ang. Resol. GSE longitude (deg.) 4
Past Results (Tibet-II >10TeV) Amenomori et al, PRL, 111, 011101 (2013) 180 Sunspot number MAX a 140 100 MIN MIN 60 20 − 1 Sun’s shadow b − 2 Deficit (%) − 3 − 4 PFSS Rss=2.5R − 5 CSSS Rss=2.5R PFSS model fails! − 6 CSSS Rss=10R 1996 1998 2000 2002 2004 2006 2008 2010 − 1 Moon’s shadow − Year − ü Discovery of a clear solar variation of the deficits − ü Comparison b/w coronal MF models (PFSS/CSSS) 5 − −
Tibet Air Shower Array 15m space 221dets Eenergy >~10TeV Ang. resol. ~0.9° 7.5m space 543 dets Energy >~3TeV Ang. resol. ~0.9° High-density Tibet (90.522 o E, 30.102 o N) 4300m a.s.l. Covering 1 solar cycle Lower energy ・ high statistics 6
10 TeV observation Similar features at Deficit/B.G.(%) Tibet-III 3TeV Sun Shadows 2000 2001 2002 2003 2004 MAX Low Statistics 2005 2006 2007 2008 2009 MIN (%) D (%) − 6.0 − 5.0 − 4.0 − 3.0 − 2.0 − 1.0 0 7
� MC Simulation of Sun Shadow ① Air shower simulation in the atmosphere -> Corsika : assuming cosmic-ray spectra, chemical compositions ② Detector simulation, triggered events are shot back to the sun -> GEANT4 : scintillation detector response ③ Trace trajectories assuming the solar MFs b/w earth and sun -> Events hitting the sun form the shadow 4th order Runge-Kutta Y (solar radius) Z (solar radius) � X (solar radius) X (solar radius) 8
Magnetic Fields between Sun and Earth Corona -> Source Surface model (CSSS well reproduces the Tibet-II sun shadows) Derived from the magnetogram measured by Kitt Peak (KPVT / SOLIS) in each C.R. IMF -> Parker spiral model with latitude dependence of the solar wind velocity taken into account. Geomag.-> Dipole model 1996 2001 (CR1910) (CR1978) 9
CSSS does not reproduce Influence of ICMEs? well at the solar maximum Deficit ‒ Obs/MC All Data - 3 TeV Data Deficit ratio /0.9 ° [%] CSSS Rss=2.5R ⦿ CSSS Rss=10R ⦿ Expected from optical Sun’s size c 2 test : c 2 / dof = 32.1 / 10 (3.4 s ) c 2 / dof = 46.9 / 10 (4.8 s ) * only stat. error 10
- ICME transit period is ~4 1 days - ICME end is plasma end at the earth. - ICME start is the eruption time at the Sun - ICMEs in the near-Earth solar wind are listed. - CMEs interact with the solar wind and the IMF. ICME Catalog http://www.srl.caltech.edu/ACE/ASC/DATA/level3/icmetable2.htm Richardson & Cane, Solar Phys (2010) Sun ü Interplanetary Coronal Mass Ejection (ICME) CME Plasma ü Exclude transit periods of ICMEs from the analysis 60 Total ICMEs Earth Analysis period 50 228 ICMEs Number of ICMEs 40 30 20 10 0 2000 2005 2010 2015 11 Years
Deficit ‒ Obs/MC All Data - 3 TeV Influence of CMEs? CSSS does not reproduce well at the solar maximum Data Deficit ratio /0.9 ° [%] CSSS Rss=2.5R ⦿ CSSS Rss=10R ⦿ Expected from optical Sun’s size c 2 test : c 2 / dof = 32.1 / 10 (3.4 s ) c 2 / dof = 46.9 / 10 (4.8 s ) * only stat. error 12
on the Sun shadow at 3 TeV Evidence for influence of ICMEs Deficit ‒ Obs/MC Exclude ICMEs - 3 TeV Data Deficit ratio /0.9 ° [%] CSSS Rss=2.5R ⦿ CSSS Rss=10R ⦿ 欠損量 [%] Expected from optical Sun’s size c 2 test : Exclude ICMEs à CSSS works c 2 / dof = 12.2 / 10 (0.6 s ) c 2 / dof = 21.0 / 10 (2.0 s ) * only stat. error 13
Depth during ICME periods Deficit ‒ Obs/MC ICME Periods - 3 TeV -> CSSS does not work Deficit ratio /0.9 ° [%] ICME Low statistics Data CSSS Rss=2.5R ⦿ CSSS Rss=10R ⦿ c 2 test : c 2 / dof = 23.9 / 7 (3.0 s ) c 2 / dof = 29.4 / 7 (3.7 s ) * only stat. error 14
Summary the temporal variation of the sun shadow based on the source surface model (CSSS ). CSSS better reproduces the observation. • We develop the MC simulation to reproduce • Comparison of Obs./MC deficit at 3TeV – CSSS model fails at the solar maximum. Ø After the ICME periods are excluded, – Systematic errors are under investigation Next Talk Shift of Shadow center depending on the IMF 15
BACKUP SLIDES 16
Ulysses Obs. “Split monopole” B r r 2 (nT) normalized to 1AU Structure Ulysses data Perihelion 1.3AU Aphelion 5.4AU Virtanen and Mursula, JGR, 115, A09110 (2010) Latitude (deg.) 17
Latitude Dependence on the SS [T] CSSS R ss =2.5R ☉ Changing Gradually across the equator [T] Step like at CSSS R ss =10.0R ☉ the equator Reproduce Ulysses obs. 18
The source surface model cannot reproduce short-term variation Deficit ‒ Obs./MC Mask ICMEs - 3 TeV Data Deficit ratio /0.9 ° [%] PFSS Rss=2.5R ⦿ CSSS Rss=2.5R ⦿ CSSS Rss=10R ⦿ Expected from optical Sun’s size c 2 test ： c 2 / dof = 29.5 / 10 (3.1 s ) Exclude ICMEs à PFSS fails c 2 / dof = 12.2 / 10 (0.6 s ) c 2 / dof = 21.3 / 10 (2.0 s ) ※ only stat. error 19
Cosmic Ray Chemical Composition ����������� ����������� Shibata( et#al .,2010( ApJ,( 716 ,(1076 20
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