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It is considered that until now in the 24th cycle of solar activity 2 ground level enhancements of solar cosmic rays (GLEs) are registered: on May 17,

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Presentation on theme: "It is considered that until now in the 24th cycle of solar activity 2 ground level enhancements of solar cosmic rays (GLEs) are registered: on May 17,"— Presentation transcript:

1 It is considered that until now in the 24th cycle of solar activity 2 ground level enhancements of solar cosmic rays (GLEs) are registered: on May 17, 2012 and on January 6, 2014. Both in quantity, and in power of GLEs the current cycle concedes to the previous. The solar proton events (SPE) registered on satellites was much more – about 30. We decided to analyze a behavior of the CR intensity at the world wide neutron monitor network in those events of 2012 when significant increase of the integral proton fluxes with the energy > 100 MeV was recorded by satellite, directly in the events on January 27, March 7, and March 13 of 2012. The proton event (enhancement of the flux of accelerated charged particles – protons and nuclear – in the Earth’s atmosphere and near Sun space environment) is one of the most important and most dangerous phenomena of the space weather, which needs careful studying. Time distribution of proton events is very inhomogeneous. For studying of proton increases it is useful to unite data of GOES satellites in which uniform and full information on X-ray flares and fluxes of protons in various energy ranges is accumulated, with data of a world network of neutron monitors. Proton increases in 1976-2013 on the background smoothed numbers of solar spots. Small circles mark the time of increase of the protons of >10 MeV energy higher 10 pfu, large circles mark the time of ground lrvrl enhancements (GLE) of solar cosmic rays (SCR) Event on January 27, 2012 The first large proton event in 2012 started on January 23, after the flare of М8.7 class from the region АО11402 (N27W71), located at western side of solar disk. The particle flux with energies of >100 MeV was 2.3 pfu. On January 24 the flux of particles of > 10 MeV reached 3400 pfu. (radiation storm of 3 level), 25 January – 6300 pfu. (radiation storm of 2 level). 26 of January proton enhancement continued on the level 1 of radiation storm. This proton increase did not come to end as on January 27, after the first in 2012 flare of the highest class, the following had begun. A source of this flare became the same active region 11402 (N27W71) which has left from the visible party of a solar limb by this time. In the night from 27 to 28 January 2012 in this area the flare of the class Х1.7 occurred. On the 27 January of 2012 a large proton increase for particles >100 МэВ (11.9 pfu) began, and flux of particles with the energy of >10 МэВ reached of 800 pfu. For particles of >100 MeV, the event was finished on the next day – 28 January 2012. For particles of >10 MeV the event turned out to be long enough and was finished on the 1 of February, 2012. Below, in figures data from neutron monitors SOPO, SOPB and station Mirny with 10 and 30 minute resolution intervals are plotted together with 5-minute data on the protons of >10 MeV, >50 MeV, >100 MeV from GOES 13. Apparently, the increase of CR intensity recorded at these stations started at the same time as increase recorded by satellite GOES 13. CR intensity recorded at NMs South Pole B (SOPB), South Pole (SOPO) with 10-minute resolution and 5- minute data of protons with energies of >10 MeV, >50 MeV, and >100 MeV by the data of GOES 13 on 27-28 January 2012 CR intensity recorded at NMS South Pole B (SOPB), South Pole (SOPO) and station Mirny with 10-minute resolution, and 5-minute data of protons with energies of >10 MeV, >50 MeV, and >100 MeV by the data of GOES 13 on 27-28 January 2012 At other high latitudinal NMs (Thule - THUL, Inuvik - INVK, McMurdo - MCMU, Terre Adelie - TERA, Fort Smith - FSMT) small increase of intensity was also observed. We suppose this event may be considered as small GLE, however, it is worthy further studying and modeling. CR intensity recorded at NMs South Pole B (SOPB), South Pole (SOPO) and Thule (THUL) with 30-minute resolution together with 5-minute data of protons with energies of >10 MeV, >50 MeV, and >100 MeV by the data of GOES 13 on 27-28 January 2012 Event on March 7, 2012 On March 7, 2012 to it the new, more powerful proton event caused by solar flares of a class X from AO11429 and AO11430 was added. Proton fluxes with energy >10 MeV reached an amplitude 6000 pfu, for energy >100 MeV – 70 pfu. For protons with energy >100 MEV, the event ended on March 11, 2012, for protons with energy >10 MEV, it proceeded, gradually weakening. In the figure 8 illustrating fluxes of protons from two flares of a class X, two maxima, probably, corresponding to arrivals of two shock waves are clearly visible. In Figures 9 and 10 data of neutron monitors are presented from the stations: Tixie Bay (TXBY), Fort Smith (FSMT), South Pole В (SOPB), South Pole (SOPO), Thule (THUL) and Inuvik (INVK) with 10- and 30- minute resolution together with 5-minute data on protons with the energies >10 MeV, >50 MeV, >100 MeV recorded at GOES 13. Small increase of CR intensity, registered by these ground level stations, coincided with the second increases of the protons at GOES 13 is clearly visible. In figures data of neutron monitors are presented from the stations: Tixie Bay (TXBY), Fort Smith (FSMT), South Pole В (SOPB), South Pole (SOPO), Thule (THUL) and Inuvik (INVK) with 10- and 30-minute resolution together with 5-minute data on protons with the energies >10 MeV, >50 MeV, >100 MeV recorded at GOES 13. Small increase of CR intensity, registered by these ground level stations, coincided with the second increases of the protons at GOES 13 is clearly visible. Count rate of neutron monitors at the stations: Tixie Bay (TXBY), Fort Smith (FSMT), South Pole В (SOPB), South Pole (SOPO), Thule (THUL) and Inuvik (INVK) with 10- and 30-minute resolution together with 5- minute data on protons with the energies >10 MeV, >50 MeV, >100 MeV recorded at GOES 13 during 6-8 March, 2012 Count rates of neutron monitors at the stations: South Pole В (SOPB) and South Pole (SOPO) with 10-minute resolution and 5-minute data on the protons with the energy >10 MeV, >50 MeV, >100 MeV by the data on satellite GOES 13, during 6-8 March, 2012 Variations of the density of 10GV rigidity CR, of equatorial anisotropy and parameters of Space Weather after the flare of M7.9 in near Earth space during 5-12 March 2012 Time of the shock arrival (SSC) at 4.21 UT coincides with the onset of CR intensity increasing at the stations SOPO and SOPB. Abrupt increase of the solar wind velocity near 8 UT could lead to the acceleration of small energy particles and to the second increase of the CR intensity recorded at SOPB and SOPO within the interval 10-13 UT. Considering event is anisotropic, with possible contribution of the magnetosphere effect. In this event coming of the releases from two filament disappearances caused in near Earth space a magnetic storm which lasted about 18 hours. In increase of intensity of the cosmic rays registered by neutron monitors, surely is a contribution of solar cosmic rays, however model calculations are necessary for more certain conclusions. Event on March 13, 2012 In figure data of NMs at the stations (SOPB) and (SOPO) with 10-minute resolution and 5-minute data of protons with the energies >10 MeV, >50 MeV, >100 MeV from GOES 13 are plotted. It is visible that growth of intensity of cosmic rays at ground level stations began close to increase of particle flux on the GOES 13 satellite that makes possible a contribution of solar cosmic rays to observed effect. Small increase was observed also at the stations Terre Adelie (TERA) and Thule (THUL). Count rates of neutron monitors at the stations: South Pole В (SOPB) and South Pole (SOPO) with 10-minute resolution and 5-minute data on the protons with the energy >10 MeV, >50 MeV, >100 MeV by the data on satellite GOES 13, on March 13, 2013 Conclusions 1) On January 27, 2012 an increase of the counting rate of ~2%, coincides in time with a proton increase at the integral intensity recorded onboard the GOES satellite (E>100 MeV) and also with increases of the average fluxes of 375, 465 and 605 MeV protons recorded on HEPAD. Such an increase is also registered on several sea level NMs that allow one to speak about GLE for this event. 2) On March 13, 2012 an increase at the counting rate similar in size to the event on January 27 is observed on several high- latitude NMs at the same time that an increase in GOES high energy protons, is presented. A GLE, possibly, was observed here. If there was no Forbush decrease at this time the situation, most probably, would been clearer. 3) The most difficult and most interesting situation that deserves a detailed analysis, modeling and further investigation, took place on March 7. In this event, the arrival of SCR to Earth coincided in time with large modulation effects in galactic CRs and with significant magnetospheric disturbance. Our analysis shows that in this event there is a possible influence of SCR on the counting rate of subpolar NMs. Count rates of neutron monitors at the stations: Alma-Ata B (AATB), Jungfraujoch (JUNG), South Pole В (SOPB) and South Pole (SOPO) during 13-14 March, 2012 It is interesting, that if compare the CR intensity at SOPO, SOPB and mid latitude stations AATB and JUNG, then, directly at the moment of the onset of proton enhancement the CR intensity at polar stations increases as compared with mid latitude stations. In figure variations of galactic CR density (for 10 GV rigidity particles) and of equatorial component of CR anisotropy calculated by GSM (Global Survey Method) on the data from world wide neutron monitor network, are presented together with data on IMF intensity and solar wind velocity before and after the flare of M7.9 class, occurred on March 13, 2012. Proton enhancements of solar cosmic rays in January and March 2012 A.Belov 1, E.Eroshenko 1, O.Kryakunova 2, N.Nikolayevskiy 2, A.Malimbayev 2, I.Thepakina 2, V.Yanke 1 1 Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radiowave Propagation (IZMIRAN), Moscow, Russia 2 Instutute of Ionosphere, Almaty, Kazakhstan CR variations (right scale) recorded at NMs Fort Smith (FSMT) and Inuvik (INVK) with 30-minute resolution and 5-minute data of protons by the data of GOES 13 on 27 January 2012, 1500 UT – 28 January 2012, 0900 UT. Average fluxes of 375, 465 and 605 MeV protons recorded on HEPAD on 27 January 2012, 1500 UT – 28 January 2012, 0900 UT. Average fluxes of 375, 465 and 605 MeV protons recorded on HEPAD on 6 March 2012, 1800 UT – 8 March 2012, 0200 UT. Average fluxes of 375, 465 and 605 MeV protons recorded on HEPAD on 13 March 2012, 1400UT – 14 March 2012, 1000 UT.


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