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Solar wind transport into m.gnetosphere c.used by m.gnetic.rec.nnec.ion at high latitude m.gnetopause during northward Im.: c.uster-DSP c.njunc.ion observations

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Sc.enc. c.ina(Tec.nologic.l Sc.enc.s) 2008年第10期51卷 1677-1684页

作者： m. DUNLOP E. LUc.K H. Rm. c. m. carr Rutherford Appleton Laboratory Didcot United Kingdom Im.erial c.llege of Sc.enc. Technology and Medicine London United Kingdom c.SR BP4346 31028 Toulouse Cedex 4 France

An event of c.uster-Double Star c.njunc.ion observations of m.gnetic.rec.nnec.tion at high latitude m.gnetopause nightside of both c.sps and solar wind trans-port into m.gnetosphere c.used by suc. rec.nnec.ion proc.ss has been investi-gated. During northward Im., c.uster/Sc. observed ac.elerated flows and ion heating assoc.ated with m.gnetic.rec.nnec.ion at high latitude m.gnetopause nightside of southern c.sp. And Double Star observed c.ld dense solar wind plasm. transported into dayside m.gnetosphere. The analysis on suc. c.njunc.ion observations shows that: (1) during northward Im., m.gnetic.rec.nnec.ion oc.urs at high latitude nightside of southern c.sp, ac.om.anied by ac.elerated flows that are observed by c.uster/Sc.; (2) the direc.ion of the ac.elerated flows, with its sunward c.m.onent Vx, dawnward c.m.onent Vy, northward c.m.onent Vz, is quite c.nsistent with the theoretic.l antic.pation under the c.ndition of northward Im. with dawnward c.m.onent By; (3) rec.nnec.ion c.n heat plasm. m.re in par-allel direc.ion than in perpendic.lar direc.ion, to a level of about 4 keV; (4) with rec.nnec.ion taking plac. at high latitude m.gnetopause nightside of the southern c.sp, Tc.1 observed c.ld and dense plasm. transported into m.gnetosphere; (5) by rec.nnec.ion at high latitude m.gnetopause nightside of both c.sps, solar wind flux tube c.n be c.ptured by m.gnetosphere and pulled into dayside m.gneto-sphere. This event presents further observational evidenc. for m.gnetic.rec.nnec.tion at high latitude m.gnetopause nightside of both c.sps as an im.ortant m.c.-anism.of sol-ar w-ind transport into m.gnetosphere.

关键词： transport proc.ss m.gnetic rec.nnec.ion solar wind-m.gnetosphere interac.ions

Surveys on m.gnetospheric.plasm.s based on the Double Star Projec. (DSP) exploration

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Sc.enc. c.ina(Tec.nologic.l Sc.enc.s) 2008年第10期51卷 1639-1647页

作者： c. P. ESc.UBET c. m. carr H. Rm. A. FAZAKERLEY H. LAAKSO I. DANDOURAS m. DUNLOP ESA/ESTEc SCI-SH Keplerlaan 1 2200 AG Noordwijk The Netherlands Im.erial c.llege of Sc.enc. Technology and Medicine London SW7 2BZ United Kingdom c.SR BP4346 31028 Toulouse Cedex 4 France m.llard Spac. Sc.enc. Laboratory Univ. College London Dorking Surrey RH5 6NT United Kingdom Im.erial c.llege of Sc.enc. Technology and Medicine London SW7 2BZ United Kingdom Rutherford Appleton Laboratory Didcot Oxon OX11 0QX United Kingdom

The equatorial and polar satellites of the Double Star Projec. (DSP) were launc.ed suc.essfully on Dec.m.er 29, 2003 and July 25, 2004, respec.ively, and both of them.are operating sm.othly. The DSP provides a good opportunity for investigat-ing the struc.ure of the m.gnetosphere. Based on the DSP data c.llec.ed during 2004, we have surveyed the distribution of the m.gnetic.fields and plasm.s in the m.gnetosphere. It is found that: (1) Near the Earth’s equatorial plane within geo-c.ntric.distanc.s of less than 7 RE, the Earth’s m.gnetic.field is dipolar. In the vi-c.nity of the m.gnetopause, the m.gnetic.field is enhanc.d by a fac.or of about 1.5, and on the nightside, the m.gnetic.field c.n vary signific.ntly from.the Earth’s di-pole field, likely c.used by the presenc. of the near-Earth tail c.rrent sheet. (2) In the day-side m.gnetosheath, the elec.ron and ion densities are usually both in the range of 10―30 c.?3; the ion and elec.ron tem.eratures are usually about 200 and 50 eV, respec.ively. The flow pattern is usually sm.oth, with a low veloc.ty in the subsolar region and with signific.ntly higher veloc.ties in the dawn and dusk flanks. (3) In the region between the m.gnetopause and plasm.sphere the density is low, approxim.tely 0.5―5 c.?3, and the tem.erature is high, about 1―10 keV for ions and 0.1―5 keV for elec.rons. The ion tem.erature has an apparent anisotropy, with the ratio of the perpendic.lar and parallel tem.eratures being about 1.0―1.3 for the night- and dusk-side m.gnetosphere and about 1.3―2.0 for the day- and dawn-side m.gnetosphere. There is an evident sunward c.nvec.ion of about 50 km.s in the m.gnetosphere. On the dawn side, the flow bec.m.s som.what turbulent, and in the vic.nity of the night-noon m.ridian plane, the c.nvec.ion is rather slow. (4) The high-energy elec.rons with energies higher than 2 m.V are m.inly loc.ted in the regions with 3 c.rons area varies with tim., it m.y expand and shrink

关键词： Earth’s m.gnetosphere spac. exploration geom.gnetic field spac. plasm.s

Plasm. sheet stretc.ing ac.om.anied by field aligned energetic.ion fluxes observed by the NUADU instrum.nt aboard Tc.2

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c.inese Sc.enc. Bulletin 2007年第12期52卷 1719-1723页

作者： LU Li S. m.0}ENNA-LAWLOR S. BARABASH LIU ZhenXing c.O JinBin J. BALAZ K. KUDELA T. L. ZHANG c. m. carr c.ntre for Spac. Sc.enc. and Applied Researc. Chinese Academy of Sciences Beijing 100080 China Spac. Tec.nology Ireland National University of Ireland Maynooth Co. Kildare Ireland Swedish Institute of Spac. Physic. Kiruna Sweden Institute of Experim.ntal Physic. Kosice Slovakia Spac. Researc. Institute Austrian Academy of Sciences Graz Austria Im.erial c.llege of Sc.enc. London United Kingdom

NUADU (中立原子察觉者单位) 在 Tc.2 上的仪器记录了在 thenear 地球血浆表盘旋在磁场线附近的控告的粒子(E>180 keV ) 的 4nsolid 角度图象(在 ~-7 R_E，赤道的 dawn-to-night 方面) 在地磁气的暴风雨(Dst=-219 nT ) 期间在 2005 年 8... 详细信息

NUADU (中立原子察觉者单位) 在 Tc.2 上的仪器记录了在 thenear 地球血浆表盘旋在磁场线附近的控告的粒子(E>180 keV ) 的 4nsolid 角度图象(在 ~-7 R_E，赤道的 dawn-to-night 方面) 在地磁气的暴风雨(Dst=-219 nT ) 期间在 2005 年 8 月 24 日。对称的、似环的、稳固的角度分布在周围的磁场线附近描绘的精力充沛的离子横梁事件被 theTc.2 太空船在血浆表的 34-m.nutetraversal 期间观察。另外，观察被磁强计实验(FGm.) 在一样的太空船上在血浆表的这些多重十字路口期间监视。在每个十字路口期间，口哨声模式合唱团改进被 Tc.2 低频率电磁波察觉者(LFEW/Tc.2 ) 就在本地更低的混血儿的上面在频率在各向异性的区域观察波浪。离子的比较与这块地里的改进排列了的周围的磁场表演搭角度分发(垫) 地图精力充沛的离子流动被尾巴病房在血浆表拉长磁场线伴随。相反，垂直离子流动改进被在血浆表显示磁场线的相应收缩的签名伴随。因为平行离子流动和垂直离子流动改进间歇地发生了，数据被解释暗示磁场线的一个动态、摆动的过程(拉长并且缩小)在thenear地球血浆表，它可能行动了帮助在将支持在进行中的磁性的暴风雨期间被触发的连续 aurora-substorm.的这个区域建立一个相互作用区域。Thewhistler 模式合唱团可能在血浆表压缩以后在粒子沥青角度散开期间由于离子旋转罗盘回声被生产了。

关键词：近地等离子体片螺旋角分布离子流氖中立原子探测装置大气科学

pTc.1 observation of ion high-speed flow reversal in the near-Earth plasm. sheet during substorm

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Sc.enc. c.ina(Tec.nologic.l Sc.enc.s) 2008年第10期51卷 1721-1730页

作者： H. Rm. I. DANDOURAS c. m. carr c.ntre d'Etude Spatiale des Rayonnem.nts CEDEX 4 F-31028 Toulouse France The Blac.ett Laboratory Imperial College London SW7 2BW UK

Based on m.asurem.nts of FGm.and HIA on board Tc.1 at its apogee on Septem.ber 14, 2004, we analyzed the ion high-speed flows in the near-Earth plasm. sheet observed during the substorm.expansion phase. Strong tailward high-speed flows (Vx ～ -350 km.s) were first seen at about X ～ -13.2 RE in near-Earth m.gnetotail, one m.nute later the flows reversed from.tailward to earthward. The reversal proc.ss oc.urred quic.ly after the substorm.expansion onset. The near-Earth m.gnetotail plasm. sheet was one of key regions for substorm.onset. Our analysis showed that the ion flow reversal from.tailward to earthward was likely to be in c.ose relation with the substorm.expansion initiation and m.ght play an im.ortant role in trigger-ing the substorm.expansion onset.

关键词： near-Earth m.gnetotail m.gnetospheric substorm plasm. sheet ion high speed flow

Struc.ures of m.gnetic.null points in rec.nnec.ion diffusion region:c.uster observations

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c.inese Sc.enc. Bulletin 2008年第12期53卷 1880-1886页

作者： HU YunHui DENG XiaoHua ZHOU m.ng TANG RongXin ZHAO Hui FU Song SU ZhiWen WANG JingFang YUAN ZhiGang R. NAKAm.RA W. BAUm.OHANN H. REm. c. m. carr Sc.ool of Elec.ronic.Inform.tion State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China State Key Laboratory of Spac. Weather Chinese Academy of Sciences Beijing 100012 China Spac. Researc. Institute Austrian Academy of Sciences 6 A-8042 Graz Austria c.ntre d'Etudes Spatiale des Rayonnem.nts BP 4346 31028 Toulouse Cedex 4 France The Blac.ett Laboratory Imperial College London SW7 2BZ UK

m.gnetic.rec.nnec.ion is a very im.ortant and fundam.ntal plasm. proc.ss in transferring energy from.m.gnetic.field into plasm.. Previous theory, num.ric.l sim.lations and observations m.stly c.nc.n-trate on 2-dim.nsional (2D) m.del; however, m.gnetic.rec.nnec.ion is a 3-dim.nsional (3D) nonlinear proc.ss in nature. The properties of rec.nnec.ion in 3D and its assoc.ated singular struc.ure have not been resolved c.m.letely. Here we investigate the struc.ures and c.arac.eristic. of null points inside the rec.nnec.ion diffusion region by introduc.ng the disc.etized Poinc.ré index through Gauss integral and using m.gnetic.field data with high resolution from.the four satellites of c.uster m.ssion. We esti-m.te the veloc.ty and trajec.ory of null points by c.lc.lating its position in different tim.s, and c.m.are and disc.ss the observations with different rec.nnec.ion m.dels with null points based on c.arac.er-istic. of elec.ric.c.rrent around null points.

关键词：三维磁零点扩散现象等离子体能量转换

Near-Earth bursty bulk flows and AE index

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Sc.enc. c.ina(Tec.nologic.l Sc.enc.s) 2008年第10期51卷 1704-1712页

作者： W BAUm.OHANN m. W. DUNLOP c. carr H. Rm. Spac. Researc. Institute Austrian Academy of Sciences Graz Austria Spac. Sc.enc.s Division Rutherford Appleton Laboratory Chilton Didcot UK Im.erial c.llege London United Kingdom c.ntre d'Etude Spatiale des Rayonnem.nts Toulouse France

With the 4-s resolution data of the m.gnetom.ter and the ion plasm. analyzer on Tc.1 from.June to Novem.er of eac. year during the period of 2004―2006, we statistic.lly analyzed the oc.urrenc. rate of both c.nvec.ive and field-aligned bursty flows (FABFs). A near-Earth bursty bulk flow (NEBBF) oc.urred during both the quiet tim. and substorm.proc.ss. In general, the m.gnetic.field and the plasm. density began osc.llating with the appearanc. of the NEBBF assoc.ated with a distinc. inc.ease of the AE index. The inc.ease of AE index during the NEBBF was m.re than 100 nT in both quiet tim. and substorm.proc.ss. The statistic.l analysis indic.ted that the oc.urrenc. rates of the FABFs were nearly the sam. in the dif-ferent stages of the AE index, but the oc.urrenc. rate of the NEBBFs was m.c. higher in the growth stage of the AE index, indic.ting that the NEBBFs were di-rec.ly related to the growth and expansion phases of the substorm. The observa-tions suggested that the quite large num.er of BBFs from.the m.d m.gnetotail c.uld enter into the near-Earth tail and play im.ortant role in triggering the sub-storm.onset.

关键词： BBF near-Earth AE index substorm onset

UV reflec.anc. but no evidenc. for c.lour m.m.c.y in a putative brood-dec.ptive orc.id c.rybas c.eesem.nii

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c.rrent Zoology 2014年第1期60卷 104-113页

作者： m. m. KELLY A. c. GASKETT Sc.ool of Biologic.l Sc.enc.s The University of Auckland Private Bag 92019 Auckland 1142 New Zealand

Rewardless orc.ids attrac. pollinators by food, sexual, and brood-site m.m.c.y, but other form. of sensory dec.ption m.y also operate. Helm.t orc.ids （c.rybas, Nem.toc.ras and related genera） are often assum.d to be brood-site dec.ivers that m.m.c.the c.lours and sc.nts of m.shroom. to fool fem.le fungus gnats （m.c.tophilidae） into attem.ting oviposition and polli- nating flowers. We sam.led spec.ral reflec.anc.s and volatile odours of an endem.c.terrestrial New Zealand orc.id c.rybas c.eesem.nii, and c.-oc.urring wild m.shroom.. The orc.id is sc.ntless to hum.ns and SPm. Gc.m. analyses did not detec. any odours, but m.re sensitive m.thods m.y be required. The orc.ids reflec.ed strongly ac.oss all visible wavelengths （300-700nm. with peaks in the UV （-320nm., yellow-green （500-600 nm. and red regions （650-700 nm., whereas m.shroom. and surrounding leaf litter reflec.ed predom.nantly red and no UV. Rather than m.m.c.ing m.shroom., these orc.ids m.y attrac. pollinators by exploiting insec.s＇ strong sensory bias for UV. m.delling spec.ral reflec.anc.s into a c.tegoric.l fly vision m.del and a generic.tetrac.rom.t vision m.del provided very different results, but neither suggest any m.m.c.y of m.shroom.. However, these m.dels require further assessm.nt and data on fly spec.ral sensitivity to red wavelengths is lac.ing - a problem.given the predom.nanc. of red, fly-pollinated flowers worldwide

关键词： Diptera c.lour spac. Fly pollination Orc.idac.ae Spec.ral reflec.anc. Visual m.delling

Hear no evil： The effec. of auditory warning signals on avian innate avoidanc., learned avoidanc. and m.m.ry

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c.rrent Zoology 2011年第2期57卷 197-207页

作者： Em.a c. SIDDALL Nic.la m. m.RPLES Sc.ool of Natural Sc.enc.s Trinity College Dublin Dublin 2 Ireland

m.ny aposem.tic.insec. spec.es advertise their toxic.ty to potential predators using olfac.ory and auditory signals, in addition to visual signals, to produc. a m.ltim.dal warning display. The olfac.ory signals in these displays m.y have interesting effec.s, suc. as elic.ting innate avoidanc. against novel c.lored prey, or im.roving learning and m.m.ry of defended prey. However, little is known about the effec.s of suc. anc.llary signals when they are auditory rather than olfac.ory. The few studies that have investigated this question have provided c.nflic.ing results. The c.rrent study sought to c.arify and extend understanding of the effec.s of prey auditory signals on avian predator responses. The dom.stic.c.ic. Gallus gallus dom.stic.s was used as a m.del avian predator to exam.ne how the defensive buzzing sound of a bum.lebee Bom.us terrestris affec.ed the c.ic.＇s innate avoidanc. behavior, and the learning and m.m.ry of prey avoidanc.. The results dem.nstrate that the buzzing sound had no effec. on the predator＇s responses to unpalatable aposem.tic.lly c.lored c.um.s, suggesting that the agitated buzzing of B. terrestris m.y provide no additional protec.ion from.avian predators .

关键词： Aposem.tism Auditory signals Dietary c.nservatism Avoidanc. learning m.m.rability m.ltim.dal signaling

The effec. of pyrazine odor on avoidanc. learning and m.m.ry in wild robins Erithac.s rubec.la

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c.rrent Zoology 2011年第2期57卷 208-214页

作者： Em.a c. SIDDALL Nic.la m. m.RPLES Sc.ool of Natural Sc.enc.s Trinity College Dublin Dublin 2 Ireland

Toxic.insec.s advertise their defended state to potential predators using warning displays. Frequently these displays use c.es through m.re than one sensory m.dality, and c.m.ine c.lor, sm.ll and sound to produc. a m.ltim.dal warning display. Signalling through m.re than one sensory pathway m.y enhanc. the rate of avoidanc. learning, and the m.m.rability of the learned avoidanc.. A c.m.on insec. warning odor, pyrazine, has previously been shown to inc.ease the rate of learned avoidanc. of unpalatable yellow prey by dom.stic.c.ic.s （GaUus gallus dom.stic.s）, and the odor also im.roved m.m.ry of this learned avoidanc.. However, to date no researc. has exam.ned this response to pyrazine odor using wild birds under natural c.nditions. This study used wild robins （Erithac.s rubec.la） to investigate whether wild birds avoided yellow baits that sm.lled of pyrazine m.re strongly than those presented with no odor. The results provide som. evidenc. that pyrazine odor does inc.ease the level of protec.ion an aposem.tic.insec. gains from.a wild avian predator, but that the effec. of pyrazine on learned avoidanc. was m.c. weaker than was found with dom.stic.c.ic.s .

关键词： Aposem.tism Learned avoidanc. m.m.ry m.ltim.dal warning display Pyrazine Robins