基于ACE飞船观测的银河宇宙线与太阳风变化的统计研究

郭孝城; 曹世豪; 熊明

doi:10.11728/cjss2020.06.969

基于ACE飞船观测的银河宇宙线与太阳风变化的统计研究

doi: 10.11728/cjss2020.06.969

中国科学院国家空间科学中心空间天气学国家重点实验室北京 100190;中国科学院大学地球与行星科学学院北京 100049

基金项目:

中国科学院空间科学战略性先导科技专项（XDB41000000，XDA15052500，XDA1701030），国家自然科学基金项目（41874171，41674146，41574159），中国科学院前沿科学重点研究计划项目（QYZDJ-SSW-JSC028），民用航天技术预先研究项目（D030202，D020301）共同资助

详细信息

作者简介:
郭孝城,E-mail:xcguo@swl.ac.cn

中图分类号: P352
计量
- 文章访问数: 577
- HTML全文浏览量: 30
- PDF下载量: 96
- 被引次数: 0
出版历程
- 收稿日期: 2020-01-14
- 修回日期: 2020-09-25
- 刊出日期: 2020-11-15

Statistical Investigation on the Galactic Cosmic Rays and Solar Wind Variation Based on ACE Observations

State Key Laboratory of Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing 100190;College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049

摘要

摘要: 基于ACE飞船的资料，通过时序迭加方法统计分析了最近两个太阳活动极小年时期（2007.0-2009.0和2016.5-2019.0年）的宇宙线计数与太阳风参数的关系.结果表明，宇宙线的计数受太阳风共转流相互作用区的强烈影响，宇宙线计数变化与快慢太阳风流界面的位置密切相关，例如流界面的穿越通常伴随着宇宙线计数的下降.分析表明，第一时段的具有“雪犁”效应的宇宙线计数下降对应于流界面附近的扩散系数急剧下降，而第二时段的非“雪犁”效应的计数下降可能是由穿越流界面后的扩散系数增大引起的.日球层电流片也与宇宙线计数变化存在一定的相关性，宇宙线粒子在日球层电流片附近存在一定程度的堆积.太阳风对宇宙线的作用机制表明，宇宙线的漂移和扩散效应决定了其在1AU附近的分布变化.
- 银河宇宙线 /
- 共转流相互作用区 /
- 流界面 /
- 日球层电流片
Abstract: Galactic Cosmic Rays (GCRs) are originated from the interstellar medium and modulated by the heliospheric magnetic field when they enter the heliosphere. Based on the GCR and plasma observations from ACE spacecraft, the relation between the GCR counts and the solar wind parameters during the recent two periods of solar minimum (the years of 2007.0-2009.0 and 2016.5-2019.0) was analyzed by means of the Superposed Epoch Analysis (SEA) method. The results indicate that GCRs are strongly modulated by the Corotating Interaction Regions (CIR) in solar wind, the Stream Interfaces (SI) sandwiched between fast and slow solar wind are closely related with the depression of GCR counts. The mechanism of the GCR variation is investigated through the empirical diffusion coefficients. The so-called "snow-plough" effect of GCR variation prior to the SI crossing appears during the first period, then the GCR counts decrease after the crossing, which corresponds to the sudden drop of diffusion coefficient at the SI. However, this effect is not observed for the second period, the decrease of GCR counts are simply caused by the enhancement of the diffusion coefficient after the SI crossing. Moreover, Heliospheric Current Sheet (HCS) correlate with GCR counts well, the GCRs drift along the current sheet and then accumulate to a pileup structure, which is physically balanced between their diffusion and drift effects. Finally, based on the observation and Parker transport theory, we discuss the physical mechanism of the GCR variation for the crossings of SIs and HCS, and proposed that the interplay between drift and diffusion determines the GCR distribution and variation at a heliocentric distance of 1AU.
- Galactic Cosmic Rays (GCR) /
- Corotating interaction regions /
- Stream Interfaces (SI) /
- Heliospheric current sheet

HTML全文

参考文献(40)

[1]	ACKERMANN M, AJELLO M, ALLAFORT A, et al. Detection of the characteristic pion-decay signature in supernova remnants[J]. Science, 2013, 339:807-811
[2]	CUMMINGS A C, STONE E C, HEIKKILA B C, et al. Galactic cosmic rays in the local interstellar medium: voyager 1 observations and model results[J]. Astrophys. J., 2016, 831:18
[3]	GUO X, FLORINSKI V. Galactic cosmic-ray modulation near heliopause[J]. Astrophys. J., 2014, 793:18
[4]	SCHLICKEISER R. Cosmic Ray Astrophysics[M]. Berlin: Springer, 2002
[5]	PARKER E N. The passage of energetic charged particles through interplanetary space[J]. Planet. Space Sci., 1965, 13(1):9
[6]	JOKIPⅡ J R, KOPRIVA D A. Effects of particle drift on the transport of cosmic rays. Ⅲ. Numerical models of galactic cosmic-ray modulation[J]. Astrophys. J., 1979, 234:384-392
[7]	KOTA J, JOKIPⅡ J R. The role of corotating interaction regions in cosmic-ray modulation[J]. Geophys. Res. Lett., 1991, 18:1979-1800
[8]	JOKIPⅡ J R, THOMAS B. Effects of drift on the transport of cosmic rays. IV. modulation by a wavy interplanetary current sheet[J]. Astrophys. J., 1981, 243:1115-1122
[9]	ALANIA M V, MODZELEWSKA R, WAWRZYNCZAK A. On the relationship of the 27-day variations of the solar wind velocity and galactic cosmic ray intensity in minimum epoch of solar activity[J]. Sol. Phys., 2011, 270:629-641
[10]	BURLAGA L F, MCDONALD F B, NESS N F, et al. Interplanetary flow systems associated with cosmic ray modulation in 1977-1980[J]. J. Geophys. Res., 1984, 89(A8):6579
[11]	POTGIETER M S, LE ROUX J A. The long-term heliospheric modulation of galactic cosmic rays according to a time-dependent drift model with merged interaction regions[J]. Astrophys. J., 1994, 423:817
[12]	LANGNER U W, POTGIETER M S. Effects of the solar wind termination shock and heliosheath on the heliospheric modulation of galactic and anomalous Helium[J]. Ann. Geophys., 2004, 22:3063-3072
[13]	KOTA J, JOKIPⅡ J R. The role of corotating interaction regions in cosmic-ray modulation[J]. Geophys. Res. Lett., 1991, 18:1979-1800
[14]	KOTA J, JOKIPⅡ J R. Corotating variations of cosmic rays near the south heliospheric pole[J]. Science, 1995, 268:1024-1025
[15]	RICHARDSON I G. Energetic particles and corotating interaction regions in the solar wind[J]. Space Sci. Rev., 2004, 111(3):267
[16]	LESKE R A, CUMMINGS A C, MEWALDT R A, et al. Anomalous and galactic cosmic rays at 1AU during the cycle 23/24 solar minimum[J]. Space Sci. Rev., 2013, 176(1/2/3/4):253
[17]	RICHARDSON I G. The relationship between recurring cosmic ray depressions and corotating solar wind streams at ≤1AU: IMP8 and Helios1 and 2 anticoincidence guard rate observations[J]. J. Geophys. Res., 1996, 101(A6):13483
[18]	GUO X, FLORINSKI V. Galactic cosmic-ray intensity modulation by corotating interaction region stream interfaces at 1AU[J]. Astrophys. J., 2016, 826:65
[19]	GHANBARI K, FLORINSKI V, GUO X, et al. Galactic cosmic rays modulation in the vicinity of corotating interaction regions: observations during the last two solar minina[J]. Astrophys. J., 2019, 882:54
[20]	BADRUDDIN R S Y, YADAV N R. Intensity variation of cosmic rays near the heliospheric current sheet[J]. Planet. Space Sci., 1985, 33(2):191
[21]	EI-BORIE M A. Cosmic-ray intensities near the heliospheric current sheet throughout three solar activity cycles[J]. J. Phys. G: Nuclear Part. Phys., 2001, 27(4):773
[22]	THOMAS S R, OWENS M J, LOCKWOOD M, et al. Galactic cosmic ray modulation near the heliospheric current sheet[J]. Sol. Phys., 2014, 289(7):2653
[23]	OKAZAKI Y, FUSHISHITA A, NARUMI T, et al. Drift effects and the cosmic ray density gradient in a solar rotation period: first observation with the Global Muon Detector Network (GMDN)[J]. Astrophys. J., 2008, 681(1):693
[24]	STONE E C, FRANDSEN A M, MEWALDT R A, et al. The advanced composition explorer[J]. Space Sci. Rev., 1998, 86(1/4):1
[25]	ABRAMENKO V, YURCHYSHYN V, LINKER J, et al. Low-latitude coronal holes at the minimum of the 23rd solar cycle[J]. Astrophys. J., 2010, 712:813
[26]	MCCOMAS D J, EBERT R W, ELLIOTT H A, et al. Weaker solar wind from the polar coronal holes and the whole Sun[J]. Geophys. Res. Lett., 2008, 35:L18103
[27]	JIAN L, RUSSELL C T, LUHMANN J G, et al. Properties of stream interactions at one au during 1995-2004[J]. Sol. Phys., 2006, 239(1/2):337
[28]	JIAN L, RUSSELL C T, LUHMANN J G. Comparing solar minimum 23/24 with historical solar wind records at 1AU[J]. Sol. Phys., 2011, 274:321
[29]	JIAN L K, MACNEICE P J, TAKTAKISHVILI A, et al. Validation for solar wind prediction at Earth: comparison of coronal and heliospheric models installed at the CCMC[J]. Space Weather, 2015, 13:316-338
[30]	GIACALONE J, JOKIPⅡ J R. The transport of cosmic rays across a turbulent magnetic field[J]. Astrophys. J., 1999, 520:204-214
[31]	MATTHAEUS W H, QIN G, BIEBER J W, et al. Nonlinear collisionless perpendicular diffusion of charged particles[J]. Astrophys. J., 2003, 590(1):L53
[32]	POTGIETER M S. Solar modulation of cosmic rays[J]. Liv. Rev. Sol. Phys., 2013, 10:3
[33]	POTGIETER M S, VOS E E, BOEZIO M, et al. Modulation of galactic protons in the heliosphere during the unusual solar minimum of 2006 to 2009[J]. Sol. Phys., 2014, 289:391
[34]	GIACALONE J. Cosmic-ray transport coeffcients[J]. Space Sci. Rev., 1998, 83:351
[35]	JOKIPⅡ J R, KOPRIVA D A. Effects of particle drift on the transport of cosmic rays. Ⅲ. numerical models of galactic cosmic-ray modulation[J]. Astrophys. J., 1979, 234:384
[36]	STONE E C, CUMMINGS A C, MCDONALD F B, et al. Voyager 1 observes low-energy galactic cosmic rays in a region depleted of heliospheric ions[J]. Science, 2013, 341:150
[37]	FLORINSKI V, JOKIPⅡ J R, ALOUANI-BIBI F, et al. Energetic particle anisotropies at the heliospheric boundary[J]. Astrophys. J., 2013, 776:L37
[38]	KOTA J, JOKIPⅡ J R. Effects of drift on the transport of cosmic rays. VI. A three-dimensional model including diffusion[J]. Astrophys. J., 1983, 265:573
[39]	NEWKIRK G, LOCKWOOD J A. Cosmic ray gradients in the heliosphere and particle drifts[J]. Geophys. Res. Lett., 1981, 8(6):619
[40]	PARKER E N. The passage of energetic charged particles through interplanetary space[J]. Planet. Space Sci., 1965, 13:9