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Sample records for active 8b solar

  1. Measurement of the total active 8B solar neutrino flux at the Sudbury Neutrino Observatory with enhanced neutral current sensitivity

    The Sudbury Neutrino Observatory (SNO) has precisely determined the total active (vx)8B solar neutrino flux without assumptions about the energy dependence of the ve survival probability. The measurements were made with dissolved NaCl in the heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21+-0.27 (stat)+-0.38(syst)x10-6 cm-2s-1, in agreement with previous measurements and standard solar models. A global analysis of these and other solar and reactor neutrino results yields Δm2 = 7.1+1.2-0.6 x 10-5 eV2 and θ 32.5+2.4-2.3 degrees. Maximal mixing is rejected at the equivalent of 5.4 standard deviations

  2. Measurement of the Total Active 8B Solar Neutrino Flux at the Sudbury Neutrino Observatory with Enhanced Neutral Current Sensitivity

    Ahmed, S N; Beier, E W; Bellerive, A; Biller, S D; Boger, J; Boulay, M G; Bowler, M G; Bowles, T J; Brice, S J; Bullard, T V; Chan, Y D; Chen, M; Chen, X; Cleveland, B T; Cox, G A; Dai, X; Dalnoki-Veress, F; Doe, P J; Dosanjh, R S; Doucas, G; Dragowsky, M R; Duba, C A; Duncan, F A; Dunford, M; Dunmore, J A; Earle, E D; Elliott, S R; Evans, H C; Ewan, G T; Farine, J; Fergani, H; Fleurot, F; Formaggio, J A; Fowler, M M; Frame, K; Fulsom, B G; Gagnon, N; Graham, K; Grant, D R; Hahn, R L; Hall, J C; Hallin, A L; Hallman, E D; Hamer, A S; Handler, W B; Hargrove, C K; Harvey, P J; Hazama, R; Heeger, K M; Heintzelman, W J; Heise, J; Helmer, R L; Hemingway, R J; Hime, A; Howe, M A; Jagam, P; Jelley, N A; Klein, J R; Kos, M S; Krumins, A V; Kutter, T; Kyba, C C M; Labranche, H; Lange, R; Law, J; Lawson, I T; Lesko, K T; Leslie, J R; Levine, I; Luoma, S; MacLellan, R; Majerus, S; Mak, H B; Maneira, J; Marino, A D; McCauley, N; McDonald, A B; McGee, S; McGregor, G; Miin, C; Miknaitis, K K S; Miller, G G; Moffat, B A; Nally, C W; Nickel, B G; Noble, A J; Norman, E B; Oblath, N S; Okada, C E; Ollerhead, R W; Orrell, J L; Oser, S M; Ouellet, C V; Peeters, S J M; Poon, A W P; Robertson, B C; Robertson, R G H; Rollin, E; Rosendahl, S S E; Rusu, V L; Schwendener, M H; Simard, O; Simpson, J J; Sims, C J; Sinclair, D; Skensved, P; Smith, M W E; Starinsky, N; Stokstad, R G; Stonehill, L C; Tafirout, R; Takeuchi, Y; Tesic, G; Thomson, M; Thorman, M; Van Berg, R; Van de Water, R G; Virtue, C J; Wall, B L; Waller, D; Waltham, C E; Wan Chan Tseung, H; Wark, D L; West, N; Wilhelmy, J B; Wilkerson, J F; Wilson, J R; Wouters, J M; Yeh, M; Zuber, K

    2004-01-01

    The Sudbury Neutrino Observatory (SNO) has precisely determined the total active (nu_x) 8B solar neutrino flux without assumptions about the energy dependence of the nu_e survival probability. The measurements were made with dissolved NaCl in the heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21 +/- 0.27 (stat) +/- 0.38 (syst) x10^6 cm^{-2}s^{-1}, in agreement with previous measurements and standard solar models. A global analysis of these and other solar and reactor neutrino results yields Delta m^{2} = 7.1^{+1.2}_{-0.6}x10^{-5} ev^2 and theta = 32.5^{+2.4}_{-2.3} degrees. Maximal mixing is rejected at the equivalent of 5.4 standard deviations.

  3. Independent Measurement of the Total Active 8B Solar Neutrino Flux Using an Array of 3He Proportional Counters at the Sudbury Neutrino Observatory

    Peeters, Simon; SNO Collaboration,

    2008-01-01

    The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (nu_x) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54(+0.33/-0.31 stat, +0.36/-0.34 syst) x 10^6 cm^-2 s^-1, in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino res...

  4. An Independent Measurement of the Total Active 8B Solar Neutrino Flux Using an Array of 3He Proportional Counters at the Sudbury Neutrino Observatory

    Aharmim, B; Amsbaugh, J F; Anthony, A E; Banar, J; Barros, N; Beier, E W; Bellerive, A; Beltran, B; Bergevin, M; Biller, S D; Boudjemline, K; Boulay, M G; Bowles, T J; Browne, M C; Bullard, T V; Burritt, T H; Cai, B; Chan, Y D; Chauhan, D; Chen, M; Cleveland, B T; Cox-Mobrand, G A; Currat, C A; Dai, X; Deng, H; Detwiler, J; Di Marco, M; Doe, P J; Doucas, G; Drouin, P L; Duba, C A; Duncan, F A; Dunford, M; Earle, E D; Elliott, S R; Evans, H C; Ewan, G T; Farine, J; Fergani, H; Fleurot, F; Ford, R J; Formaggio, J A; Fowler, M M; Gagnon, N; Germani, J V; Goldschmidt, A; Goon, J T M; Graham, K; Guillian, E; Habib, S; Hahn, R L; Hallin, A L; Hallman, E D; Hamian, A A; Harper, G C; Harvey, P J; Hazama, R; Heeger, K M; Heintzelman, W J; Heise, J; Helmer, R L; Henning, R; Hime, A; Howard, C; Howe, M A; Huang, M; Jagam, P; Jamieson, B; Jelley, N A; Keeter, K J; Klein, J R; Kormos, L L; Kos, M; Krüger, A; Kraus, C; Krauss, C B; Kutter, T; Kyba, C C M; Lange, R; Law, J; Lawson, I T; Lesko, K T; Leslie, J R; Loach, J C; MacLellan, R; Majerus, S; Mak, H B; Maneira, J; Martin, R; McBryde, K; McCauley, N; McDonald, A B; McGee, S; Miin, C; Miller, G G; Miller, M L; Monreal, B; Monroe, J; Morissette, B; Myers, A; Nickel, B G; Noble, A J; Oblath, N S; O'Keeffe, H M; Ollerhead, R W; Orebi Gann, G D; Oser, S M; Ott, R A; Peeters, S J M; Poon, A W P; Prior, G; Reitzner, S D; Rielage, K; Robertson, B C; Robertson, R G H; Rollin, E; Schwendener, M H; Secrest, J A; Seibert, S R; Simard, O; Simpson, J J; Sinclair, L; Skensved, P; Smith, M W E; Steiger, T D; Stonehill, L C; Tesic, G; Thornewell, P M; Tolich, N; Tsui, T; Tunnell, C D; Van Wechel, T; Van Berg, R; Van Devender, B A; Virtue, C J; Walker, T J; Wall, B L; Waller, D; Wan Chan Tseung, H; Wendland, J; West, N; Wilhelmy, J B; Wilkerson, J F; Wilson, J R; Wouters, J M; Wright, A; Yeh, M; Zhang, F; Zuber, K

    2008-01-01

    The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (nu_x) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54(+0.33/-0.31 stat, +0.36/-0.34 syst) x 10^6 cm^-2 s^-1, in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Delta m^2 = 7.94(+0.42/-0.26) x 10^-5 eV^2 and theta = 33.8(+1.4/-1.3) degrees. The uncertainty on the mixing angle has been reduced from SNO's previous results.

  5. DETECTING GRAVITY MODES IN THE SOLAR 8 B NEUTRINO FLUX

    The detection of gravity modes produced in the solar radiative zone has been a challenge in modern astrophysics for more than 30 yr and their amplitude in the core is not yet determined. In this Letter, we develop a new strategy to look for standing gravity modes through solar neutrino fluxes. We note that due to a resonance effect, the gravity modes of low degree and low order have the largest impact on the 8 B neutrino flux. The strongest effect is expected to occur for the dipole mode with radial order 2, corresponding to periods of about 1.5 hr. These standing gravity waves produce temperature fluctuations that are amplified by a factor of 170 in the boron neutrino flux for the corresponding period, in consonance with the gravity modes. From current neutrino observations, we determine that the maximum temperature variation due to the gravity modes in the Sun's core is smaller than 5.8 × 10–4. This study clearly shows that due to their high sensitivity to the temperature, the 8 B neutrino flux time series is an excellent tool to determine the properties of gravity modes in the solar core. Moreover, if gravity mode footprints are discovered in the 8 B neutrino flux, this opens a new line of research to probe the physics of the solar core as non-standing gravity waves of higher periods cannot be directly detected by helioseismology but could leave their signature on boron neutrino or on other neutrino fluxes

  6. Coulomb dissociation of 8B and solar neutrino problem

    We measured the cross section for Coulomb dissociation of 8B using a radioactive 8B beam of 46.5MeV/u energy with a 208Pb target. The cross section for the 7Be(p,γ)8B capture reaction was deduced at Ecm=0.6-1.7MeV. The extracted astrophysical S17 factors were consistent with the values measured by Vaughn et al. and Filippone et al. Possible corrections due to 7Be excited state population, E1 and M2 contribution, nuclear contribution and post acceleration effects are considered. ((orig.))

  7. 7Be(p, γ)8B and the high-energy solar neutrino flux

    Despite thirty years of extensive experimental and theoretical work, the predicted solar neutrino flux is still in sharp disagreement with measurements. The solar neutrino measurements strongly suggest that the problem cannot be solved within the standard electroweak and astrophysical theories. Thus, the solar neutrino problem constitutes the strongest evidence for physics beyond the Standard Model. Whatever the solution of the solar neutrino problem turns out to be, it is of paramount importance that the input parameters of the underlying electroweak and solar theories rest upon solid ground. The most uncertain nuclear input parameter in standard solar models is the low-energy 7Be(p, γ)8B radiative capture cross section. This reaction produces 8B in the Sun, whose β+ decay is the main source of the high-energy solar neutrinos. Here, the importance of the 7Be(p, γ)8B reaction in predicting the high energy solar neutrino flux is discussed. The author presents a microscopic eight-body model and a potential model for the calculation of the 7Be(p, γ)8B cross section

  8. Indirect measurements of the solar-neutrino production reaction 7Be(p,γ)8B

    Low-energy cross sections of the 7Be(p,γ)8B reaction is of crucial importance, because they determine the high-energy solar neutrino flux. Coulomb dissociation with intermediate-energy 8B beams and low-energy proton-transfer reactions with 7Be beams have been investigated to determine indirectly the astrophysical S17 factors of the 7Be(p,γ)8B reaction. The results of these studies are generally in good agreement with the ones obtained by direct capture measurements using intense proton beams and radioactive 7Be targets

  9. How to observe 8B solar neutrinos in liquid scintillator detectors

    Ianni, A; Villante, F L

    2016-01-01

    We show that liquid organic scintillator detectors (e.g., KamLAND and Borexino) can measure the 8B solar neutrino flux by means of the nu_e charged current interaction with the 13C nuclei naturally contained in the scintillators. The neutrino events can be identified by exploiting the time and space coincidence with the subsequent decay of the produced 13N nuclei. We perform a detailed analysis of the background in KamLAND, Borexino and in a possible liquid scintillator detector at SNOLab, showing that the 8B solar neutrino signal can be extracted with a reasonable uncertainty in a few years of data taking. KamLAND should be able to extract about 18 solar neutrino events from the already collected data. Prospects for gigantic scintillator detectors (such as LENA) are also studied.

  10. Measurement of the 8B Solar Neutrino Flux with KamLAND

    Abe, S; Gando, A; Gando, Y; Ichimura, K; Ikeda, H; Inoue, K; Kibe, Y; Kimura, W; Kishimoto, Y; Koga, M; Minekawa, Y; Mitsui, T; Morikawa, T; Nagai, N; Nakajima, K; Nakamura, K; Nakamura, M; Narita, K; Shimizu, I; Shimizu, Y; Shirai, J; Suekane, F; Suzuki, A; Takahashi, H; Takahashi, N; Takemoto, Y; Tamae, K; Watanabe, H; Xu, B D; Yabumoto, H; Yonezawa, E; Yoshida, H; Yoshida, S; Enomoto, S; Kozlov, A; Murayama, H; Grant, C; Keefer, G; McKee, D; Piepke, A; Banks, T I; Bloxham, T; Detwiler, J A; Freedman, S J; Fujikawa, B K; Han, K; Kadel, R; O'Donnell, T; Steiner, H M; Winslow, L A; Dwyer, D A; Mauger, C; McKeown, R D; Zhang, C; Berger, B E; Lane, C E; Maricic, J; Miletic, T; Batygov, M; Learned, J G; Matsuno, S; Pakvasa, S; Sakai, M; Horton-Smith, G A; Tang, A; Downum, K E; Gratta, G; Tolich, K; Efremenko, Y; Kamyshkov, Y; Perevozchikov, O; Karwowski, H J; Markoff, D M; Tornow, W; Heeger, K M; Piquemal, F; Ricol, J -S; Decowski, M P

    2011-01-01

    We report a measurement of the neutrino-electron elastic scattering rate from 8B solar neutrinos based on a 123 kton-day exposure of KamLAND. The background-subtracted electron recoil rate, above a 5.5 MeV analysis threshold is 1.49+/-0.14(stat)+/-0.17(syst) events per kton-day. Interpreted as due to a pure electron flavor flux with a 8B neutrino spectrum, this corresponds to a spectrum integrated flux of 2.77+/-0.26(stat)+/-0.32(syst) x 10^6 cm^-2s^-1. The analysis threshold is driven by 208Tl present in the liquid scintillator, and the main source of systematic uncertainty is due to background from cosmogenic 11Be. The measured rate is consistent with existing measurements and with Standard Solar Model predictions which include matter enhanced neutrino oscillation.

  11. The CREB Transcription Factor Controls Transcriptional Activity of the Human RIC8B Gene.

    Maureira, Alejandro; Sánchez, Rodolfo; Valenzuela, Nicole; Torrejón, Marcela; Hinrichs, María V; Olate, Juan; Gutiérrez, José L

    2016-08-01

    Proper regulation of gene expression is essential for normal development, cellular growth, and differentiation. Differential expression profiles of mRNA coding for vertebrate Ric-8B during embryo and adult stages have been observed. In addition, Ric-8B is expressed in few cerebral nuclei subareas. These facts point to a dynamic control of RIC8B gene expression. In order to understand the transcriptional regulation of this gene, we searched for cis-elements in the sequence of the human RIC8B promoter region, identifying binding sites for the basic/leucine zipper (bZip) CREB transcription factor family (CRE sites) and C/EBP transcription factor family (C/EBP sites). CRE sites were found clustered near the transcription start site, while the C/EBP sites were found clustered at around 300 bp upstream the CRE sites. Here, we demonstrate the ability of CREB1 and C/EBPβ to bind their respective elements identified in the RIC8B promoter. Comparative protein-DNA interaction analyses revealed only the proximal elements as high affinity sites for CREB1 and only the distal elements as high affinity sites for C/EBPβ. Chromatin immunoprecipitation analyses, carried out using a human neuroblastoma cell line, confirmed the preferential association of CREB to the proximal region of the RIC8B promoter. By performing luciferase reporter assays, we found the CRE sites as the most relevant elements for its transcriptional activity. Taken together, these data show the existence of functional CREB and C/EBP binding sites in the human RIC8B gene promoter, a particular distribution of these sites and demonstrate a relevant role of CREB in stimulating transcriptional activity of this gene. J. Cell. Biochem. 117: 1797-1805, 2016. © 2016 Wiley Periodicals, Inc. PMID:26729411

  12. Borexino: New results on the solar 8B-neutrino flux and outlook on pep- and CNO-neutrinos

    Borexino is a 300 t liquid-scintillator detector designed for the real-time detection of solar neutrinos in the sub-MeV energy range. The experiment is taking data since August 2007 and has published the first real-time spectral measurements of solar 7Be-neutrinos. Based on the statistics of 3 years, Borexino has recently achieved new results for the solar 8B-neutrinos, measuring this rate down to an unprecedented energy threshold of 3 MeV. The measurements of the remaining solar neutrino fluxes of the pep-, CNO- and pp-neutrinos are currently under investigation. The talk presents the new 8B-neutrino results of Borexino and give an outlook on the current efforts on the measurements of the pep- and CNO-neutrinos.

  13. A comment on the 7Be(p,γ)8B cross section and the solar neutrino problem

    Evidence is presented which indicates that the accepted value for the cross section of the 7Be(p,γ)8B reaction at stellar energies is probably too large. It is suggested that the accepted value of the 7Li(d,p)8Li cross section, which has been used for normalization purposes, is too large; that the accepted value for the ratio of the 7Be(p,γ)8B and 7Li(d,p)8Li cross sections is too large; and that the energy dependence used to extrapolate to stellar energies from the higher energies at which measurements have been made is inaccurate. The consequent reduction of the 7Be(p,γ)8B cross section by about 30% would not be sufficient to resolve the solar neutrino problem but would significantly lessen the discrepancy between observation and calculation

  14. A Search for Periodicities in the $^8$B Solar Neutrino Flux Measured by the Sudbury Neutrino Observatory

    Aharmim, B; Anthony, A E; Beier, E W; Bellerive, A; Bergevin, M; Biller, S D; Boulay, M G; Bowler, M G; Chan, Y D; Chen, M; Chen, X; Cleveland, B T; Costin, T; Cox, G A; Currat, C A; Dai, X; Deng, H; Detwiler, J; Doe, P J; Dosanjh, R S; Doucas, G; Duba, C A; Duncan, F A; Dunford, M; Dunmore, J A; Earle, E D; Elliott, S R; Evans, H C; Ewan, G T; Farine, J; Fergani, H; Fleurot, F; Formaggio, J A; Frati, W; Fulsom, B G; Gagnon, N; Goon, J T M; Graham, K; Hahn, R L; Hallin, A L; Hallman, E D; Handler, W B; Hargrove, C K; Harvey, P J; Hazama, R; Heeger, K M; Heelan, L; Heintzelman, W J; Heise, J; Helmer, R L; Hemingway, R J; Hime, A; Howe, M A; Huang, M; Inrig, E; Jagam, P; Jelley, N A; Klein, J R; Kormos, L L; Kos, M S; Krüger, A; Kraus, C V; Krauss, C B; Krumins, A V; Kutter, T; Kyba, C C M; Labranche, H; Lange, R; Law, J; Lawson, I T; Lesko, K T; Leslie, J R; Levine, I; Loach, J C; Luoma, S; MacLellan, R; Majerus, S; Maneira, J; Marino, A D; McCauley, N; McDonald, A B; McGee, S; Miin, C; Miknaitis, K K S; Nickel, B G; Noble, A J; Norman, E B; Oblath, N S; Okada, C E; O'Keeffe, H M; Ollerhead, R W; Orebi-Gann, G D; Orrell, J L; Oser, S M; Ouvarova, T; Peeters, S J M; Poon, A W P; Pun, C S J; Rielage, K; Robertson, B C; Robertson, R G H; Rollin, E; Rosendahl, S S E; Schwendener, M H; Seibert, S R; Simard, O; Simpson, J J; Sims, C J; Sinclair, D; Sinclair, L; Skensved, P; Smith, M W E; Stokstad, R G; Stonehill, L C; Tafirout, R; Takeuchi, Y; Tesic, G; Thomson, M; Tsang, K V; Tsui, T; Van Berg, R; Virtue, C J; Wall, B L; Waller, D; Waltham, C E; Wan Chan Tseung, H; Wark, D L; Wendland, J; West, N; Wilkerson, J F; Wilson, J R; Wouters, J M; Yeh, M; Zuber, K

    2005-01-01

    A search has been made for sinusoidal periodic variations in the $^8$B solar neutrino flux using data collected by the Sudbury Neutrino Observatory over a 4-year time interval. The variation at a period of one year is consistent with modulation of the $^8$B neutrino flux by the Earth's orbital eccentricity. No significant sinusoidal periodicities are found with periods between 1 day and 10 years with either an unbinned maximum likelihood analysis or a Lomb-Scargle periodogram analysis. The data are inconsistent with the hypothesis that the results of the recent analysis by Sturrock et al., based on elastic scattering events in Super-Kamiokande, can be attributed to a 7% sinusoidal modulation of the total $^8$B neutrino flux.

  15. Halo effective field theory constrains the solar 7Be + p → 8B + γ rate

    Zhang, Xilin; Nollett, Kenneth M.; Phillips, D. R.

    2015-12-01

    We report an improved low-energy extrapolation of the cross section for the process 7Be (p , γ)8B, which determines the 8B neutrino flux from the Sun. Our extrapolant is derived from Halo Effective Field Theory (EFT) at next-to-leading order. We apply Bayesian methods to determine the EFT parameters and the low-energy S-factor, using measured cross sections and scattering lengths as inputs. Asymptotic normalization coefficients of 8B are tightly constrained by existing radiative capture data, and contributions to the cross section beyond external direct capture are detected in the data at E EFT subsumes all models into a controlled low-energy approximant, where they are characterized by nine parameters at next-to-leading order. These are fit to data, and marginalized over via Monte Carlo integration to produce the improved prediction for S (E).

  16. Trafficking and gating of hyperpolarization-activated cyclic nucleotide-gated channels are regulated by interaction with tetratricopeptide repeat-containing Rab8b-interacting protein (TRIP8b) and cyclic AMP at distinct sites

    Y. Han; Y. Noam; A.S. Lewis; J.J. Gallagher; W.J. Wadman; T.Z. Baram; D.M. Chetkovich

    2011-01-01

    Ion channel trafficking and gating are often influenced by interactions with auxiliary subunits. Tetratricopeptide repeat-containing Rab8b-interacting protein (TRIP8b) is an auxiliary subunit for neuronal hyperpolarization-activated cyclic nucleotide-gated (HCN) channels. TRIP8b interacts directly w

  17. Halo effective field theory constrains the solar 7Be + p → 8B + γ rate

    Xilin Zhang

    2015-12-01

    Full Text Available We report an improved low-energy extrapolation of the cross section for the process Be7(p,γB8, which determines the 8B neutrino flux from the Sun. Our extrapolant is derived from Halo Effective Field Theory (EFT at next-to-leading order. We apply Bayesian methods to determine the EFT parameters and the low-energy S-factor, using measured cross sections and scattering lengths as inputs. Asymptotic normalization coefficients of 8B are tightly constrained by existing radiative capture data, and contributions to the cross section beyond external direct capture are detected in the data at E<0.5 MeV. Most importantly, the S-factor at zero energy is constrained to be S(0=21.3±0.7 eVb, which is an uncertainty smaller by a factor of two than previously recommended. That recommendation was based on the full range for S(0 obtained among a discrete set of models judged to be reasonable. In contrast, Halo EFT subsumes all models into a controlled low-energy approximant, where they are characterized by nine parameters at next-to-leading order. These are fit to data, and marginalized over via Monte Carlo integration to produce the improved prediction for S(E.

  18. Measurement of the solar 8B neutrino flux with 246 live days of Borexino and observation of the MSW vacuum-matter transition

    Bellini, G; Bonetti, S; Buizza Avanzini, M; Caccianiga, B; Cadonati, L; Calaprice, F; Carraro, C; Chavarria, A; Dalnoki-Veress, F; D'Angelo, D; De Kerret, H; Derbin, A; Etenko, A; Fomenko, K; Franco, D; Galbiati, C; Gazzana, S; Giammarchi, M; Goeger-Neff, M; Goretti, A; Grieb, C; Hardy, a S; Aldo, Ianni; Andrea, Ianni; Joyce, M; Kobychev, V; Korga, G; Kryn, D; Laubenstein, M; Leung, M; Lewke, T; Litvinovich, E; Loer, B; Lombardi, P; Ludhova, L; Machulin, I; Manecki, S; Maneschg, W; Manuzio, G; Masetti, F; McCarty, K; Meindl, Q; Meroni, E; Miramonti, L; Misiaszek, M; Montanari, D; Muratova, V; Oberauer, L; Obolensky, M; Ortica, F; Pallavicini, M; Papp, L; Perasso, L; Perasso, S; Pocar, A; Raghavan, b R S; Ranucci, G; Razeto, A; Risso, P; Romani, A; Rountree, D; Sabelnikov, A; Saldanha, R; Salvo, C; Schönert, S; Simgen, H; Skorokhvatov, M; Smirnov, O; Sotnikov, A; Sukhotin, S; Suvorov, Y; Tartaglia, R; Testera, G; Vignaud, D; Vogelaar, R B; Von Feilitzsch, F; Wójcik, M; Wurm, M; Zaimidoroga, O; Zavatarelli, S; Zuzel, G

    2008-01-01

    We report the measurement of the 8B solar neutrinos interaction rate with the Borexino detector. The threshold energy of 2.8 MeV is the lowest for 8B achieved so far. The rate of 8B solar neutrino interaction as measured through their scattering on the target electrons is 0.26+-0.04(stat)+-0.02(syst) c/d/100 tons. This corresponds to an equivalent electron neutrino flux of (2.65+-0.44(stat)+-0.18(syst))x10^6 cm^-2 s^-1, as derived from the elastic scattering only, in good agreement with existing measurements and predictions. The corresponding 8B mean electron neutrino survival probability, assuming the BS07(GS98) Standard Solar Model, is 0.35+-0.10 at the effective energy of 8.6 MeV. The survival probability of the 0.862 MeV 7Be neutrinos was previously reported with a subset of these data as 0.56+-0.10. Eliminating the common sources of systematic errors, the ratio between the measured survival probabilities for 7Be and 8B neutrinos is 1.60+-0.33, 1.8 sigmas different form unity. For the first time we confir...

  19. Measurement of the efficient cross section of the reaction 7Be(p, γ)8B at low energies and implications in the problem of solar neutrinos

    The 8B produced inside the sun through the reaction 7Be(p,γ)8B is the main, and even unique, source of high energy neutrinos detected in most solar neutrino detection experiments, except with Gallex and Sage. These experiments have all measured a neutrinos flux lower than the one predicted by solar models. Several explanations have been proposed to explain this deficit, but all require a precise knowledge of the efficient cross-section of the reaction 7Be(p,γ)8B, because the neutrinos flux of 8B is directly proportional to this reaction. The direct measurement of this cross section for the solar energy is impossible because of its low value (about 1 femto-barn). In order to get round this problem, the cross sections are measured at higher energy and extrapolated to the solar energy using a theoretical energy dependence. The 6 previous experimental determinations of the efficient cross section were shared in two distinct groups with differences of about 30% which leads to an uncertainty of the same order on the high energy neutrinos flux. The re-measurement of the cross section of this reaction with a better precision is thus of prime importance. A direct measurement of the cross section in the energy range comprised between 0.35 and 1.4 MeV (cm) has been performed first. These experiments have permitted the precise measurement of each parameter involved in the determination of the cross section. Then, measurements of the cross section have been carried out with the PAPAP accelerator at 185.8, 134.7 and 111.7 keV, the lowest mass center energy never reached before. The results are in excellent agreement with those obtained at higher energies. The value obtained by extrapolation of these data for the astrophysical factor S17(0) is 19.21.3 EV-B, which leads to a significant reduction of the uncertainty on the high energy neutrinos flux of 8B. (J.S.)

  20. Measurement of the nue and Total 8B Solar Neutrino Fluxes with theSudbury Neutrino Observatory Phase I Data Set

    Aharmim, B.; Ahmad, Q.R.; Ahmed, S.N.; Allen, R.C.; Andersen,T.C.; Anglin, J.D.; Buehler, G.; Barton, J.C.; Beier, E.W.; Bercovitch,M.; Bergevin, M.; Bigu, J.; Biller, S.D.; Black, R.A.; Blevis, I.; Boardman, R.J.; Boger, J.; Bonvin, E.; Boulay, M.G.; Bowler, M.G.; Bowles, T.J.; Brice, S.J.; Browne, M.C.; Bullard, T.V.; Burritt, T.H.; Cameron, J.; Chan, Y.D.; Chen, H.H.; Chen, M.; Chen, X.; Cleveland, B.T.; Cowan, J.H.M.; Cowen, D.F.; Cox, G.A.; Currat, C.A.; Dai, X.; Dalnoki-Veress, F.; Davidson, W.F.; Deng, H.; DiMarco, M.; Doe, P.J.; Doucas, G.; Dragowsky, M.R.; Duba, C.A.; Duncan, F.A.; Dunford, M.; Dunmore, J.A.; Earle, E.D.; Elliott, S.R.; Evans, H.C.; Ewan, G.T.; Farine, J.; Fergani, H.; Ferraris, A.P.; Fleurot, F.; Ford, R.J.; Formaggio, J.A.; Fowler, M.M.; Frame, K.; Frank, E.D.; Frati, W.; Gagnon,N.; Germani, J.V.; Gil, S.; Goldschmidt, A.; Goon, J.T.M.; Graham, K.; Grant, D.R.; Guillian, E.; Hahn, R.L.; Hallin, A.L.; Hallman, E.D.; Hamer, A.S.; Hamian, A.A.; Handler, W.B.; Haq, R.U.; Hargrove, C.K.; Harvey, P.J.; Hazama, R.; Heeger, K.M.; Heintzelman, W.J.; Heise, J.; Helmer, R.L.; Henning, R.; Hepburn, J.D.; Heron, H.; Hewett, J.; Hime,A.; Howard, C.; Howe, M.A.; Huang, M.; Hykawy, J.G.; Isaac, M.C.P.; Jagam, P.; Jamieson, B.; Jelley, N.A.; Jillings, C.; Jonkmans, G.; Kazkaz, K.; Keener, P.T.; Kirch, K.; Klein, J.R.; Knox, A.B.; Komar,R.J.; Kormos, L.L.; Kos, M.; Kouzes, R.; Krueger, A.; Kraus, C.; Krauss,C.B.; Kutter, T.; Kyba, C.C.M.; Labranche, H.; Lange, R.; Law, J.; Lawson, I.T.; Lay, M.; Lee, H.W.; Lesko, K.T.; Leslie, J.R.; Levine, I.; Loach, J.C.; Locke, W.; Luoma, S.; Lyon, J.; MacLellan, R.; Majerus, S.; Mak, H.B.; Maneira, J.; Marino, A.D.; Martin, R.; McCauley, N.; McDonald,A.B.; McDonald, D.S.; McFarlane, K.; McGee, S.; McGregor, G.; MeijerDrees, R.; Mes, H.; Mifflin, C.; Miknaitis, K.K.S.; Miller, M.L.; Milton,G.; Moffat, B.A.; Monreal, B.; Moorhead, M.; Morrissette, B.; Nally,C.W.; Neubauer, M.S.; et al.

    2007-02-01

    This article provides the complete description of resultsfrom the Phase I data set of the Sudbury Neutrino Observatory (SNO). ThePhase I data set is based on a 0.65 kt-year exposure of heavy water tothe solar 8B neutrino flux. Included here are details of the SNO physicsand detector model, evaluations of systematic uncertainties, andestimates of backgrounds. Also discussed are SNO's approach tostatistical extraction of the signals from the three neutrino reactions(charged current, neutral current, and elastic scattering) and theresults of a search for a day-night asymmetry in the ?e flux. Under theassumption that the 8B spectrum is undistorted, the measurements fromthis phase yield a solar ?e flux of ?(?e) =1.76+0.05?0.05(stat.)+0.09?0.09 (syst.) x 106 cm?2 s?1, and a non-?ecomponent ?(? mu) = 3.41+0.45?0.45(stat.)+0.48?0.45 (syst.) x 106 cm?2s?1. The sum of these components provides a total flux in excellentagreement with the predictions of Standard Solar Models. The day-nightasymmetry in the ?e flux is found to be Ae = 7.0 +- 4.9 (stat.)+1.3?1.2percent (sys.), when the asymmetry in the total flux is constrained to bezero.

  1. The 3He(alpha, gamma)7Be reaction rate, solar 7Be and 8B neutrino fluxes, and the production of 7Li during the Big Bang

    The 3He(α,γ)7Be reaction plays an important role both in determining the predicted fluxes of 7Be and 8B neutrinos from our Sun, and in the calculation of primordial 7Li production. In light of the highly precise determination of the baryon-to-photon ratio from the cosmic microwave background data, it is necessary to re-determine primordial 7Li production. Recent experimental nuclear astrophysics work has led to an improved determination of the 3He(α,γ)7Be cross section, with several experiments clustered at E = 0.5 MeV center-of-mass energy and above [2, and references therein]. On the other hand, precisely calibrated 7Be and 8B neutrino fluxes from the Sun are now available. Assuming the accepted solar central temperature to be correct, the neutrino flux data can be used to determine the 3He(α,γ)7Be cross section at the solar Gamow peak, E = 0.03 MeV. The energy range relevant for Big Bang 7Li production lies just between 0.03 and 0.5 MeV. The poster aims to use the two above described levels in order to improve the precision of the predicted primordial abundance of 7Li. It updates a previous work that appeared before the new cross section, solar neutrino and microwave background data were available. (author)

  2. Electron Energy Spectra, Fluxes, and Day-Night Asymmetries of $^{8}$B Solar Neutrinos from the 391-Day Salt Phase SNO Data Set

    Aharmim, B; Anthony, A E; Beier, E W; Bellerive, A; Bergevin, M; Biller, S D; Boger, J; Boulay, M G; Bowler, M G; Bullard, T V; Chan, Y D; Chen, M; Chen, X; Cleveland, B T; Cox, G A; Currat, C A; Dai, X; Dalnoki-Veress, F; Deng, H; Doe, P J; Dosanjh, R S; Doucas, G; Duba, C A; Duncan, F A; Dunford, M; Dunmore, J A; Earle, E D; Elliott, S R; Evans, H C; Ewan, G T; Farine, J; Fergani, H; Fleurot, F; Formaggio, J A; Frame, K; Frati, W; Fulsom, B G; Gagnon, N; Graham, K; Grant, D R; Hahn, R L; Hall, J C; Hallin, A L; Hallman, E D; Handler, W B; Hargrove, C K; Harvey, P J; Hazama, R; Heeger, K M; Heelan, L; Heintzelman, W J; Heise, J; Helmer, R L; Hemingway, R J; Hime, A; Howard, C; Howe, M A; Huang, M; Jagam, P; Jelley, N A; Klein, J R; Kormos, L L; Kos, M S; Krüger, A; Kraus, C V; Krauss, C B; Krumins, A V; Kutter, T; Kyba, C C M; Labranche, H; Lange, R; Law, J; Lawson, I T; Lesko, K T; Leslie, J R; Levine, I; Loach, J C; Luoma, S; MacLellan, R; Majerus, S; Mak, H B; Maneira, J; Marino, A D; McCauley, N; McDonald, A B; McGee, S; McGregor, G; Miin, C; Miknaitis, K K S; Moffat, B A; Nally, C W; Neubauer, M S; Nickel, B G; Noble, A J; Norman, E B; Oblath, N S; Okada, C E; Ollerhead, R W; Orrell, J L; Oser, S M; Ouellet, C V; Peeters, S J M; Poon, A W P; Rielage, K; Robertson, B C; Robertson, R G H; Rollin, E; Rosendahl, S S E; Rusu, V L; Schwendener, M H; Seibert, S R; Simard, O; Simpson, J J; Sims, C J; Sinclair, D; Skensved, P; Smith, M W E; Starinsky, N; Stokstad, R G; Stonehill, L C; Tafirout, R; Takeuchi, Y; Tesic, G; Thomson, M; Thorman, M; Tsui, T; Van Berg, R; Van de Water, R G; Virtue, C J; Wall, B L; Waller, D; Waltham, C E; Wan Chan Tseung, H; Wark, D L; Wendland, J; West, N; Wilkerson, J F; Wilson, J R; Wittich, P; Wouters, J M; Wright, A; Yeh, M; Zuber, K

    2005-01-01

    Results are reported from the complete salt phase of the Sudbury Neutrino Observatory experiment in which NaCl was dissolved in the D$_2$O target. The addition of salt enhanced the signal from neutron capture, as compared to the pure D$_2$O detector. By making a statistical separation of charged-current events from other types based on event-isotropy criteria, the effective electron recoil energy spectrum has been extracted. In units of $ 10^6$ cm$^{-2}$ s$^{-1}$, the total flux of active-flavor neutrinos from $^8$B decay in the Sun is found to be $4.94^{+0.21}_{-0.21}{(stat)}^{+0.38}_{-0.34}{(syst)}$ and the integral flux of electron neutrinos for an undistorted $^8$B spectrum is $1.68^{+0.06}_{-0.06}{(stat)}^{+0.08}_{-0.09}{(syst)}$; the signal from ($\

  3. Measurement of the efficient cross section of the reaction {sup 7}Be(p, {gamma}){sup 8}B at low energies and implications in the problem of solar neutrinos; Mesures de la section efficace de la reaction {sup 7}Be(p,{gamma}){sup 8}B a basses energies et implications dans le probleme des neutrinos solaires

    Hammache, Fairouz

    1999-07-01

    The {sup 8}B produced inside the sun through the reaction {sup 7}Be(p,{gamma}){sup 8}B is the main, and even unique, source of high energy neutrinos detected in most solar neutrino detection experiments, except with Gallex and Sage. These experiments have all measured a neutrinos flux lower than the one predicted by solar models. Several explanations have been proposed to explain this deficit, but all require a precise knowledge of the efficient cross-section of the reaction {sup 7}Be(p,{gamma}){sup 8}B, because the neutrinos flux of {sup 8}B is directly proportional to this reaction. The direct measurement of this cross section for the solar energy is impossible because of its low value (about 1 femto-barn). In order to get round this problem, the cross sections are measured at higher energy and extrapolated to the solar energy using a theoretical energy dependence. The 6 previous experimental determinations of the efficient cross section were shared in two distinct groups with differences of about 30% which leads to an uncertainty of the same order on the high energy neutrinos flux. The re-measurement of the cross section of this reaction with a better precision is thus of prime importance. A direct measurement of the cross section in the energy range comprised between 0.35 and 1.4 MeV (cm) has been performed first. These experiments have permitted the precise measurement of each parameter involved in the determination of the cross section. Then, measurements of the cross section have been carried out with the PAPAP accelerator at 185.8, 134.7 and 111.7 keV, the lowest mass center energy never reached before. The results are in excellent agreement with those obtained at higher energies. The value obtained by extrapolation of these data for the astrophysical factor S{sub 17}(0) is 19.21.3 EV-B, which leads to a significant reduction of the uncertainty on the high energy neutrinos flux of {sup 8}B. (J.S.)

  4. Solar activity and medicine

    Temur' yants, N.A.; Makeev, V.B.

    Some statistical data on the effect of solar activity on the human nervous system (variation of the number of traffic accidents) blood-vascular system (variation of mortality due to blood-vascular diseases) circulatory system (change of leucocyte concentration in human blood), epidemics (sick rates of scarlet fever and malaria). It is shown that the increase in solar activity is a factor of risk for patients and weakened persons.

  5. Electron energy spectra, fluxes, and day-night asymmetries of 8B solar neutrinos from the 391-day salt phase SNO data set

    The first phase of the Sudbury Neutrino Observatory, proved that neutrinos change flavour on the way from the sun to the earth, and improved significantly the evidence that neutrinos oscillate. From June 2001 the Sudbury Neutrino Observatory ran with 2000 kg of NaCl added to its 1000 tonnes heavy water target until October 2003. The addition of salt enhanced SNO's ability to detect solar neutrinos in several ways: it improved the neutral current measurement, as well as allowing a better statistical separation of neutral current and charged current events. In this talk I will discuss the experimental aspects of the second phase of the SNO experiment and the resulting measurements presented in the publication of March this year. I'll also give an outlook of the third phase of the SNO experiment which has just started and will continue until december 2006. (author)

  6. Physics of solar activity

    Sturrock, Peter A.

    1993-01-01

    The aim of the research activity was to increase our understanding of solar activity through data analysis, theoretical analysis, and computer modeling. Because the research subjects were diverse and many researchers were supported by this grant, a select few key areas of research are described in detail. Areas of research include: (1) energy storage and force-free magnetic field; (2) energy release and particle acceleration; (3) radiation by nonthermal electrons; (4) coronal loops; (5) flare classification; (6) longitude distributions of flares; (7) periodicities detected in the solar activity; (8) coronal heating and related problems; and (9) plasma processes.

  7. Magnetohydrodynamic process in solar activity

    Jingxiu Wang

    2014-01-01

    Full Text Available Magnetohydrodynamics is one of the major disciplines in solar physics. Vigorous magnetohydrodynamic process is taking place in the solar convection zone and atmosphere. It controls the generating and structuring of the solar magnetic fields, causes the accumulation of magnetic non-potential energy in the solar atmosphere and triggers the explosive magnetic energy release, manifested as violent solar flares and coronal mass ejections. Nowadays detailed observations in solar astrophysics from space and on the ground urge a great need for the studies of magnetohydrodynamics and plasma physics to achieve better understanding of the mechanism or mechanisms of solar activity. On the other hand, the spectacular solar activity always serves as a great laboratory of magnetohydrodynamics. In this article, we reviewed a few key unresolved problems in solar activity studies and discussed the relevant issues in solar magnetohydrodynamics.

  8. 15 CFR 8b.16 - Discrimination prohibited.

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Discrimination prohibited. 8b.16 Section 8b.16 Commerce and Foreign Trade Office of the Secretary of Commerce PROHIBITION OF DISCRIMINATION... Accessibility § 8b.16 Discrimination prohibited. No qualified handicapped individual shall, because a...

  9. 15 CFR 8b.11 - Discrimination prohibited.

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Discrimination prohibited. 8b.11 Section 8b.11 Commerce and Foreign Trade Office of the Secretary of Commerce PROHIBITION OF DISCRIMINATION... Practices § 8b.11 Discrimination prohibited. (a) General. (1) No qualified handicapped individual shall,...

  10. 15 CFR 8b.4 - Discrimination prohibited.

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Discrimination prohibited. 8b.4 Section 8b.4 Commerce and Foreign Trade Office of the Secretary of Commerce PROHIBITION OF DISCRIMINATION... Provisions § 8b.4 Discrimination prohibited. (a) General. No qualified handicapped individual shall, on...

  11. Solar activity and earth's climate

    Benestad, Rasmus E

    2006-01-01

    Introduces the subject of solar activity and the connection with Earth''s climate. This book commences with a review of the historical progress on the understanding of the solar-terrestrial connection and moves on to an objective scrutiny of the various hypothesis. It focuses on how knowledge about the solar cycle and Earth''s climate is obtained.

  12. Solar collector manufacturing activity, 1990

    The Solar Collector Manufacturing Activity 1990 report prepared by the Energy Information Administration (EIA) presents summary and detailed data provided by domestic manufacturers on shipments of solar thermal collectors and photovoltaic cells and modules. Summary data on solar thermal collector shipments are presented for the period 1974 through 1990. Summary data on photovoltaic cell and module shipments are presented for the period 1982 through 1990. Detailed information for solar thermal collectors and photovoltaic cells and modules are presented for 1990

  13. The enigma of solar activity

    The paper reviews the outstanding puzzles presented by the activity of the Sun. It has become clear in the last ten years that the cause of all the many different forms of solar activity can be traced to the convection and circulation within the Sun. The theory of convection, circulation, and nonuniform rotation is fundamental to the understanding of solar activity. (Auth.)

  14. Solar activity and myocardial infarction.

    Szczeklik, E; Mergentaler, J; Kotlarek-Haus, S; Kuliszkiewicz-Janus, M; Kucharczyk, J; Janus, W

    1983-01-01

    The correlation between the incidence of myocardial infarction, sudden cardiac death, the solar activity and geomagnetism in the period 1969-1976 was studied, basing on Wrocław hospitals material registered according to WHO standards; sudden death was assumed when a person died within 24 hours after the onset of the disease. The highest number of infarctions and sudden deaths was detected for 1975, which coincided with the lowest solar activity, and the lowest one for the years 1969-1970 coinciding with the highest solar activity. Such an inverse, statistically significant correlation was not found to exist between the studied biological phenomena and geomagnetism. PMID:6851574

  15. Activity Cycle of Solar Filaments

    K. J. Li; Q. X. Li; P. X. Gao; J. Mu; H. D. Chen; T. W. Su

    2007-06-01

    Long-term variation in the distribution of the solar filaments observed at the Observatorie de Paris, Section de Meudon from March 1919 to December 1989 is presented to compare with sunspot cycle and to study the periodicity in the filament activity, namely the periods of the coronal activity with the Morlet wavelet used. It is inferred that the activity cycle of solar filaments should have the same cycle length as sunspot cycle, but the cycle behavior of solar filaments is globally similar in profile with, but different in detail from, that of sunspot cycles. The amplitude of solar magnetic activity should not keep in phase with the complexity of solar magnetic activity. The possible periods in the filament activity are about 10.44 and 19.20 years. The wavelet local power spectrum of the period 10.44 years is statistically significant during the whole consideration time. The wavelet local power spectrum of the period 19.20 years is under the 95% confidence spectrum during the whole consideration time, but over the mean red-noise spectrum of = 0.72 before approximate Carrington rotation number 1500, and after that the filament activity does not statistically show the period. Wavelet reconstruction indicates that the early data of the filament archive (in and before cycle 16) are more noiseful than the later (in and after cycle 17).

  16. Deciphering Solar Magnetic Activity: On Grand Minima in Solar Activity

    McIntosh, Scott W

    2015-01-01

    The Sun provides the energy necessary to sustain our existence. While the Sun provides for us, it is also capable of taking away. The weather and climatic scales of solar evolution and the Sun-Earth connection are not well understood. There has been tremendous progress in the century since the discovery of solar magnetism - magnetism that ultimately drives the electromagnetic, particulate and eruptive forcing of our planetary system. There is contemporary evidence of a decrease in solar magnetism, perhaps even indicators of a significant downward trend, over recent decades. Are we entering a minimum in solar activity that is deeper and longer than a typical solar minimum, a "grand minimum"? How could we tell if we are? What is a grand minimum and how does the Sun recover? These are very pertinent questions for modern civilization. In this paper we present a hypothetical demonstration of entry and exit from grand minimum conditions based on a recent analysis of solar features over the past 20 years and their p...

  17. Solar Activity and Classical Physics

    2001-01-01

    This review of solar physics emphasizes several of the more conspicuous scientific puzzles posed by contemporary observational knowledge of the magnetic activity of the Sun. The puzzles emphasize how much classical physics we have yet to learn from the Sun. The physics of solar activity is based on the principles of Newton, Maxwell, Lorentz, Boltzmann, et. al., along with the principles of radiative transfer. In the large, these principles are expressed by magnetohydrodynamics. A brief derivation of the magnetohydrodynamic induction and momentum equations is provided, with a discussion of popular misconceptions.

  18. 15 CFR 8b.25 - Nonacademic services.

    2010-01-01

    ... Secondary Education § 8b.25 Nonacademic services. (a) Physical education and athletics. (1) In providing physical education courses and athletics and similar aid, benefits, or services to any of its students, a... offers physical education courses or that operates or sponsors intercollegiate, club, or...

  19. 15 CFR 8b.13 - Employment criteria.

    2010-01-01

    ... job skills aptitude, or whatever factor the test purports to measure, rather than reflecting the... Practices § 8b.13 Employment criteria. (a) A recipient may not make use of any employment test or other... handicapped individuals unless; (1) The test score or other selection criterion, as used by the recipient,...

  20. Neuroprotection of Neuro2a cells and the cytokine suppressive and anti-inflammatory mode of action of resveratrol in activated RAW264.7 macrophages and C8-B4 microglia.

    Steiner, Nicole; Balez, Rachelle; Karunaweera, Niloo; Lind, Joanne M; Münch, Gerald; Ooi, Lezanne

    2016-05-01

    Chronic inflammation is a hallmark of neurodegenerative disease and cytotoxic levels of nitric oxide (NO) and pro-inflammatory cytokines can initiate neuronal death pathways. A range of cellular assays were used to assess the anti-inflammatory and neuroprotective action of resveratrol using murine microglial (C8-B4), macrophage (RAW264.7) and neuronal-like (Neuro2a) cell lines. We examined the release of NO by Griess assay and used a Bioplex array to measure a panel of pro- and anti-inflammatory cytokines and chemokines, in response to the inflammatory stimuli lipopolysaccharide (LPS) and interferon-γ (IFN-γ). Resveratrol was a potent inhibitor of NO and cytokine release in activated macrophages and microglia. The activity of resveratrol increased marginally in potency with longer pre-incubation times in cell culture that was not due to cytotoxicity. Using an NO donor we show that resveratrol can protect Neuro2a cells from cytotoxic concentrations of NO. The protective effect of resveratrol from pro-inflammatory signalling in RAW264.7 cells was confirmed in co-culture experiments leading to increased survival of Neuro2a cells. Together our data are indicative of the potential neuroprotective effect of resveratrol during nitrosative stress and neuroinflammation. PMID:26522689

  1. Forecasting the solar activity cycle: new insights

    Nandy, Dibyendu; Karak, Bidya Binay

    2013-01-01

    Having advanced knowledge of solar activity is important because the Sun's magnetic output governs space weather and impacts technologies reliant on space. However, the irregular nature of the solar cycle makes solar activity predictions a challenging task. This is best achieved through appropriately constrained solar dynamo simulations and as such the first step towards predictions is to understand the underlying physics of the solar dynamo mechanism. In Babcock-Leighton type dynamo models, ...

  2. Monitoring of the solar activity and solar energetic particles

    Solar activity is the source of various space weather phenomena in geospace and deep space. Solar X-ray radiation in flare, energetic particles, coronal mass ejection (CME) can cause various kind of disturbance near earth space. Therefore, detailed monitoring of the solar activity and its propagation in the interplanetary space is essential task for space weather. For example, solar energetic particle which sometimes affect spacecraft operation and manned space flight, is considered to be produced by solar flares and travelling shockwave caused by flares and CME. The research and development of monitoring technique and system for various solar activity has been an important topic of space weather forecast program in NICT. In this article, we will introduce the real time data acquisitions of STEREO and optical and radio observations of the Sun at Hiraiso Solar Observatory. (author)

  3. Forecasting the solar activity cycle: new insights

    Nandy, Dibyendu

    2013-01-01

    Having advanced knowledge of solar activity is important because the Sun's magnetic output governs space weather and impacts technologies reliant on space. However, the irregular nature of the solar cycle makes solar activity predictions a challenging task. This is best achieved through appropriately constrained solar dynamo simulations and as such the first step towards predictions is to understand the underlying physics of the solar dynamo mechanism. In Babcock-Leighton type dynamo models, the poloidal field is generated near the solar surface whereas the toroidal field is generated in the solar interior. Therefore a finite time is necessary for the coupling of the spatially segregated source layers of the dynamo. This time delay introduces a memory in the dynamo mechanism which allows forecasting of future solar activity. Here we discuss how this forecasting ability of the solar cycle is affected by downward turbulent pumping of magnetic flux. With significant turbulent pumping the memory of the dynamo is ...

  4. Magnetohydrodynamic process in solar activity

    Jingxiu Wang; Jie Jiang

    2014-01-01

    Magnetohydrodynamics is one of the major disciplines in solar physics. Vigorous magnetohydrodynamic process is taking place in the solar convection zone and atmosphere. It controls the generating and structuring of the solar magnetic fields, causes the accumulation of magnetic non-potential energy in the solar atmosphere and triggers the explosive magnetic energy release, manifested as violent solar flares and coronal mass ejections. Nowadays detailed observations in solar astrophysics from s...

  5. New measurement of 8B Coulomb dissociation and E2 component

    The Coulomb dissociation of 8B in the field of 208Pb was studied at around 50 MeV/u incident energy. The astrophysical S-factors for the 7Be(p,γ)8B reaction, a key of the solar neutrino production, were deduced. Possible mixture of the E2 components are expected to be small based on our measurement of angular distribution in a wide range. This supports our earlier analysis assuming pure E1 transitions. (orig.)

  6. Evidence for distinct modes of solar activity

    Usoskin, I G; Gallet, Y; Roth, R; Licht, A; Joos, F; Kovaltsov, G A; Thebault, E; Khokhlov, A

    2014-01-01

    Aims. The Sun shows strong variability in its magnetic activity, from Grand minima to Grand maxima, but the nature of the variability is not fully understood, mostly because of the insufficient length of the directly observed solar activity records and of uncertainties related to long-term reconstructions. Here we present a new adjustment-free reconstruction of solar activity over three millennia and study its different modes. Methods. We present a new adjustment-free, physical reconstruction of solar activity over the past three millennia, using the latest verified carbon cycle, 14C production, and archeomagnetic field models. This great improvement allowed us to study different modes of solar activity at an unprecedented level of details. Results. The distribution of solar activity is clearly bi-modal, implying the existence of distinct modes of activity. The main regular activity mode corresponds to moderate activity that varies in a relatively narrow band between sunspot numbers about 20 and 67. The exist...

  7. Deciphering Solar Magnetic Activity: On Grand Minima in Solar Activity

    Scott William Mcintosh; Leamon, Robert J.

    2015-01-01

    The Sun provides the energy necessary to sustain our existence. While the Sun provides for us, it is also capable of taking away. The weather and climatic scales of solar evolution and the Sun-Earth connection are not well understood. There has been tremendous progress in the century since the discovery of solar magnetism - magnetism that ultimately drives the electromagnetic, particulate and eruptive forcing of our planetary system. There is contemporary evidence of a decrease in solar magne...

  8. Deciphering solar magnetic activity: on grand minima in solar activity

    Mcintosh, Scott W.; Leamon, Robert J.

    2015-01-01

    The Sun provides the energy necessary to sustain our existence. While the Sun provides for us, it is also capable of taking away. The weather and climatic scales of solar evolution and the Sun-Earth connection are not well understood. There has been tremendous progress in the century since the discovery of solar magnetism - magnetism that ultimately drives the electromagnetic, particulate and eruptive forcing of our planetary system. There is contemporary evidence of a decrease in solar magne...

  9. Solar activity and climate in Central America

    Javier Bonatti; Esteban Araya; Walter Fernández

    2000-01-01

    Possible effects of solar activity on the records of air surface temperature and rainfall in Central America are analysed. The correlation between the series of sunspot numbers, surface air temperature and precipitation, is poor. However an increasing tendency in the series is observed for the time period considered. Using Fourier analysis, frequency peaks were found close to 11 years and 5 years for both solar and climate data. This suggest that solar activity might be a factor which affects...

  10. Sustainable Buildings. Using Active Solar Power

    Sharp, M. Keith [Univ. of Louisville, KY (United States); Barnett, Russell [Univ. of Louisville, KY (United States)

    2015-04-20

    The objective of this project is to promote awareness and knowledge of active solar energy technologies by installing and monitoring the following demonstration systems in Kentucky: 1) Pool heating system, Churchill Park School, 2) Water heating and daylighting systems, Middletown and Aiken Road Elementary Schools, 3) Photovoltaic street light comparison, Louisville Metro, 4) up to 25 domestic water heating systems across Kentucky. These tasks will be supported by outreach activities, including a solar energy installer training workshop and a Kentucky Solar Energy Conference.

  11. New measurement and analysis of the $^{7}Be(p,\\gamma) ^{8}B$ cross section

    Hammache, F; Aguer, P; Angulo, C; Barhoumi, S; Brillard, L; Chemin, J F; Claverie, G; Coc, A; Hussonnois, M; Jacotin, M; Kiener, J; Lefebvre, A; Scheurer, J N; Thibaud, J P; Virassamynaïken, E

    1998-01-01

    Cross sections for the 7Be(p,gamma)8B reaction have been measured for E_c.m.= 0.35-1.4 MeV using radioactive 7Be targets. Two independent measurements carried out with different beam conditions, different targets and detectors are in excellent agreement. A statistical comparison of these measurements with previous results leads to a restricted set of consistent data. The deduced zero-energy S-factor S(0) is found to be 15-20% smaller than the previously recommended value. This implies a 8B solar neutrino flux lower than previously predicted in various standard solar models.

  12. Solar Activity and the Climate of Prebaikalia

    V. A. Kovalenko; G.A. Zherebtsov; S.I. Molodykh

    2005-01-01

    This paper presents convincing evidence for the reality of manifestations of solar variability in climate characteristics of the Prebaikalia. A numerical estimate is obtained of this influence on ground air temperature. It is shown that the main meaningful variations in air temperature in the region for the period1881-1960 were caused by solar activity. Since the 1960s till the present, with the influence of solar variability continuing, a clear-cut influence of another factor has been observed, the role of which has been steadily increasing, and in the hst decade it has now exceeded the contribution of solar variability. Research results on the variations in hydrological characteristics of Lake Baikal and the Angara river and their connection with solar activity are presented. It is shown that these characteristics are closely correlated with the duration of solar cycles.

  13. Science Activities in Energy: Solar Energy II.

    Oak Ridge Associated Universities, TN.

    Included in this science activities energy package are 14 activities related to solar energy for secondary students. Each activity is outlined on a single card and is introduced by a question such as: (1) how much solar heat comes from the sun? or (2) how many times do you have to run water through a flat-plate collector to get a 10 degree rise in…

  14. Solar activities and Climate change hazards

    Hady, A. A., II

    2014-12-01

    Throughout the geological history of Earth, climate change is one of the recurrent natural hazards. In recent history, the impact of man brought about additional climatic change. Solar activities have had notable effect on palaeoclimatic changes. Contemporary, both solar activities and building-up of green-house gases effect added to the climatic changes. This paper discusses if the global worming caused by the green-house gases effect will be equal or less than the global cooling resulting from the solar activities. In this respect, we refer to the Modern Dalton Minimum (MDM) which stated that starting from year 2005 for the next 40 years; the earth's surface temperature will become cooler than nowadays. However the degree of cooling, previously mentioned in old Dalton Minimum (c. 210 y ago), will be minimized by building-up of green-house gases effect during MDM period. Regarding to the periodicities of solar activities, it is clear that now we have a new solar cycle of around 210 years. Keywords: Solar activities; solar cycles; palaeoclimatic changes; Global cooling; Modern Dalton Minimum.

  15. A History of Solar Activity over Millennia

    Ilya G. Usoskin

    2013-03-01

    Full Text Available Presented here is a review of present knowledge of the long-term behavior of solar activity on a multi-millennial timescale, as reconstructed using the indirect proxy method. The concept of solar activity is discussed along with an overview of the special indices used to quantify different aspects of variable solar activity, with special emphasis upon sunspot number. Over long timescales, quantitative information about past solar activity can only be obtained using a method based upon indirect proxies, such as the cosmogenic isotopes 14C and 10Be in natural stratified archives (e.g., tree rings or ice cores. We give an historical overview of the development of the proxy-based method for past solar-activity reconstruction over millennia, as well as a description of the modern state. Special attention is paid to the verification and cross-calibration of reconstructions. It is argued that this method of cosmogenic isotopes makes a solid basis for studies of solar variability in the past on a long timescale (centuries to millennia during the Holocene. A separate section is devoted to reconstructions of strong solar energetic-particle (SEP events in the past, that suggest that the present-day average SEP flux is broadly consistent with estimates on longer timescales, and that the occurrence of extra-strong events is unlikely. Finally, the main features of the long-term evolution of solar magnetic activity, including the statistics of grand minima and maxima occurrence, are summarized and their possible implications, especially for solar/stellar dynamo theory, are discussed.

  16. New NSO Solar Surface Activity Maps

    Henney, C. J.; Harvey, J. W.

    2001-05-01

    Using NSO-Kitt Peak Vacuum Telescope (KPVT) synoptic data, we present several new solar surface activity maps. The motivation is to test conventional wisdom about conditions that are likely to produce solar activity such as flares, coronal mass ejections and high speed solar wind streams. The ultimate goal is to improve real-time, observation-based models for the purpose of predicting solar activity. A large number of maps will eventually be produced based on the wide range of ideas and models of the conditions thought to lead to solar activity events. When data from the new SOLIS instruments becomes available, the range of possible models that can be tested will be greatly expanded. At present, the daily maps include ones that show magnetic field complexity, emerging flux and high speed solar wind sources. As a proxy for local magnetic potential energy, each element of the magnetic complexity map is the distance-weighted rms of the opposing ambient magnetic field. The flux emergence map is the difference between the two most recent absolute magnetic flux images. The solar wind source map is produced from coronal hole area data. The new maps are available on the NSO-Kitt Peak World Wide Web page. This research was supported in part by the Office of Navel Research Grant N00014-91-J-1040. The NSO-Kitt Peak data used here are produced cooperatively by NSF/AURA, NASA/GSFC, and NOAA/SEC.

  17. Volcanic eruptions and solar activity

    Stothers, Richard B.

    1989-01-01

    The historical record of large volcanic eruptions from 1500 to 1980 is subjected to detailed time series analysis. In two weak but probably statistically significant periodicities of about 11 and 80 yr, the frequency of volcanic eruptions increases (decreases) slightly around the times of solar minimum (maximum). Time series analysis of the volcanogenic acidities in a deep ice core from Greenland reveals several very long periods ranging from about 80 to about 350 yr which are similar to the very slow solar cycles previously detected in auroral and C-14 records. Solar flares may cause changes in atmospheric circulation patterns that abruptly alter the earth's spin. The resulting jolt probably triggers small earthquakes which affect volcanism.

  18. Solar activity forcing of the middle atmosphere

    K. Mohanakumar

    Full Text Available Studies on the influence of solar activity in 11-year cycle on middle atmospheric thermodynamic parameters, such as temperature, pressure and density, and zonal and meridional wind components over three meteorological rocket launching stations, located in the tropics (Thumba, mid-latitude (Volgograd and high-latitude (Heiss Island regions of the northern hemisphere have been carried out. The temperature in all the three regions showed a negative response in the stratosphere and positive association in the mesosphere with the changes in solar activity. The temperature decreases by 2–3% from its mean value in the stratosphere and increases by 4–6% in the mesosphere for an increase in 100 units of solar radio flux. Atmospheric pressure is found to be more sensitive to solar changes. An average solar maximum condition enhances the pressure in the stratosphere by 5% and in the upper mesosphere by 16–18% compared to the respective mean values. Density also showed strong association with the changes in solar activity. Increase in the solar radio flux tends to strengthen winter westerlies in the upper stratosphere over the mid-latitude and summer easterlies in the middle stratosphere over tropics. Larger variability in the zonal wind is noted near stratopause height. Results obtained from the study indicate that there is an external force exerted on the Earth's atmosphere during the period of high solar activity. These results can be incorporated for further studies on the dynamics of the middle atmosphere in association with the changes in solar activity.

  19. A History of Solar Activity over Millennia

    Usoskin Ilya G.

    2008-10-01

    Full Text Available Presented here is a review of present knowledge of the long-term behavior of solar activity on a multi-millennial timescale, as reconstructed using the indirect proxy method.The concept of solar activity is discussed along with an overview of the special indices used to quantify different aspects of variable solar activity, with special emphasis upon sunspot number.Over long timescales, quantitative information about past solar activity can only be obtained using a method based upon indirect proxy, such as the cosmogenic isotopes 14C and 10Be in natural stratified archives (e.g., tree rings or ice cores. We give an historical overview of the development of the proxy-based method for past solar-activity reconstruction over millennia, as well as a description of the modern state. Special attention is paid to the verification and cross-calibration of reconstructions. It is argued that this method of cosmogenic isotopes makes a solid basis for studies of solar variability in the past on a long timescale (centuries to millennia during the Holocene.A separate section is devoted to reconstructions of strong solar–energetic-particle (SEP events in the past, that suggest that the present-day average SEP flux is broadly consistent with estimates on longer timescales, and that the occurrence of extra-strong events is unlikely.Finally, the main features of the long-term evolution of solar magnetic activity, including the statistics of grand minima and maxima occurrence, are summarized and their possible implications, especially for solar/stellar dynamo theory, are discussed.

  20. BMP8B Increases Brown Adipose Tissue Thermogenesis through Both Central and Peripheral Actions

    Whittle AJ; Carobbio S; Martins L; Slawik M; Hondares E; V\\xe1zquez MJ; Morgan D; Csikasz RI; Gallego R; Rodriguez-Cuenca S; Dale M.; Virtue S; Villarroya F; Cannon B; Rahmouni K

    2012-01-01

    Summary Thermogenesis in brown adipose tissue (BAT) is fundamental to energy balance and is also relevant for humans. Bone morphogenetic proteins (BMPs) regulate adipogenesis, and, here, we describe a role for BMP8B in the direct regulation of thermogenesis. BMP8B is induced by nutritional and thermogenic factors in mature BAT, increasing the response to noradrenaline through enhanced p38MAPK/CREB signaling and increased lipase activity. Bmp8b−/− mice exhibit impaired thermogenesis and reduce...

  1. Global water cycle and solar activity variations

    Al-Tameemi, Muthanna A.; Chukin, Vladimir V.

    2016-05-01

    The water cycle is the most active and most important component in the circulation of global mass and energy in the Earth system. Furthermore, water cycle parameters such as evaporation, precipitation, and precipitable water vapour play a major role in global climate change. In this work, we attempt to determine the impact of solar activity on the global water cycle by analyzing the global monthly values of precipitable water vapour, precipitation, and the Solar Modulation Potential in 1983-2008. The first object of this study was to calculate global evaporation for the period 1983-2008. For this purpose, we determined the water cycle rate from satellite data, and precipitation/evaporation relationship from 10 years of Planet Simulator model data. The second object of our study was to investigate the relationship between the Solar Modulation Potential (solar activity index) and the evaporation for the period 1983-2008. The results showed that there is a relationship between the solar modulation potential and the evaporation values for the period of study. Therefore, we can assume that the solar activity has an impact on the global water cycle.

  2. 15 CFR 8b.20 - Admission and recruitment.

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Admission and recruitment. 8b.20... Secondary Education § 8b.20 Admission and recruitment. (a) General. Qualified handicapped may not, on the basis of handicap, be denied admission or be subjected to discrimination in admission or recruitment...

  3. Magnetic Helicity Injection in Solar Active Regions

    Hong-Qi Zhang

    2006-01-01

    We present the evolution of magnetic field and its relationship with magnetic (current) helicity in solar active regions from a series of photospheric vector magnetograms obtained by Huairou Solar Observing Station, longitudinal magnetograms by MDI of SOHO and white light images of TRACE. The photospheric current helicity density is a quantity reflecting the local twisted magnetic field and is related to the remaining magnetic helicity in the photosphere, even if the mean current helicity density brings the general chiral property in a layer of solar active regions. As new magnetic flux emerges in active regions, changes of photospheric current helicity density with the injection of magnetic helicity into the corona from the subatmosphere can be detected, including changes in sign caused by the injection of magnetic helicity of opposite sign. Because the injection rate of magnetic helicity and photospheric current helicity density have different means in the solar atmosphere,the injected magnetic helicity is probably not proportional to the current helicity density remaining in the photosphere. The evidence is that rotation of sunspots does not synchronize exactly with the twist of photospheric transverse magnetic field in some active regions (such as, delta active regions). They represent different aspects of magnetic chirality. A combined analysis of the observational magnetic helicity parameters actually provides a relative complete picture of magnetic helicity and its transfer in the solar atmosphere.

  4. Effects of the March 1989 solar activity

    Two weeks of intense solar activity which produced an historically great magnetic storm occurred in March 1989. Here, the observed effects of that activity are described, including the injection of energetic particles to geostationary orbit, the extreme magnetospheric compression, the cosmic ray penetration, radiation belt precipitation, geomagnetic storms and substorms, and extremely large auroral zone, and radio aurorae that resulted from the activity are reviewed. The effects of the activity on technological systems on earth and in space are addressed

  5. Active Solar Energy Use Approaching Sustainability

    NikouJavadiEshkalak,

    2014-06-01

    Full Text Available Nowadays, sustainability becomes one of the most important issues that should be taken into consideration in various fields especially in architecture. Our responsibility for the future generation insinuates us for using renewable energy sources and integrating this pioneer system into the built environment. Although the world is facing problems of fossil fuel resources but unfortunately Utilization of solar energy received limited attention until recently. However, Integrating of active solar energy devices into the building envelopes is one of the good strategies for heat producing and power generating simultaneously from the same building. This paper discusses some characteristics about integration of PV s and solar thermal collectors. Therefore, the aim of this paper is to find suitable and possible ways of PV s and solar thermal collector's building integration in order to increasing energy efficiency without any impact on architectural features. \\

  6. Microbial solar cells: applying photosynthetic and electrochemically active organisms

    Strik, D.P.B.T.B.; Timmers, R.A.; Helder, M.; Steinbusch, K.J.J.; Hamelers, H.V.M.; Buisman, C.J.N.

    2011-01-01

    Microbial solar cells (MSCs) are recently developed technologies that utilize solar energy to produce electricity or chemicals. MSCs use photoautotrophic microorganisms or higher plants to harvest solar energy, and use electrochemically active microorganisms in the bioelectrochemical system to gener

  7. Multiscale statistical analysis of coronal solar activity

    Gamborino, Diana; Martinell, Julio J

    2016-01-01

    Multi-filter images from the solar corona are used to obtain temperature maps which are analyzed using techniques based on proper orthogonal decomposition (POD) in order to extract dynamical and structural information at various scales. Exploring active regions before and after a solar flare and comparing them with quiet regions we show that the multiscale behavior presents distinct statistical properties for each case that can be used to characterize the level of activity in a region. Information about the nature of heat transport is also be extracted from the analysis.

  8. Solar Energy Education. Home economics: student activities. Field test edition

    1981-03-01

    A view of solar energy from the standpoint of home economics is taken in this book of activities. Students are provided information on solar energy resources while performing these classroom activities. Instructions for the construction of a solar food dryer and a solar cooker are provided. Topics for study include window treatments, clothing, the history of solar energy, vitamins from the sun, and how to choose the correct solar home. (BCS)

  9. The phospholipid flippase ATP8B1 mediates apical localization of the cystic fibrosis transmembrane regulator.

    van der Mark, Vincent A; de Jonge, Hugo R; Chang, Jung-Chin; Ho-Mok, Kam S; Duijst, Suzanne; Vidović, Dragana; Carlon, Marianne S; Oude Elferink, Ronald P J; Paulusma, Coen C

    2016-09-01

    Progressive familial intrahepatic cholestasis type 1 (PFIC1) is caused by mutations in the gene encoding the phospholipid flippase ATP8B1. Apart from severe cholestatic liver disease, many PFIC1 patients develop extrahepatic symptoms characteristic of cystic fibrosis (CF), such as pulmonary infection, sweat gland dysfunction and failure to thrive. CF is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR), a chloride channel essential for epithelial fluid transport. Previously it was shown that CFTR transcript levels were strongly reduced in livers of PFIC1 patients. Here we have investigated the hypothesis that ATP8B1 is important for proper CFTR expression and function. We analyzed CFTR expression in ATP8B1-depleted intestinal and pulmonary epithelial cell lines and assessed CFTR function by measuring short-circuit currents across transwell-grown ATP8B1-depleted intestinal T84 cells and by a genetically-encoded fluorescent chloride sensor. In addition, we studied CFTR surface expression upon induction of CFTR transcription. We show that CFTR protein levels are strongly reduced in the apical membrane of human ATP8B1-depleted intestinal and pulmonary epithelial cell lines, a phenotype that coincided with reduced CFTR activity. Apical membrane insertion upon induction of ectopically-expressed CFTR was strongly impaired in ATP8B1-depleted cells. We conclude that ATP8B1 is essential for correct apical localization of CFTR in human intestinal and pulmonary epithelial cells, and that impaired CFTR localization underlies some of the extrahepatic phenotypes observed in ATP8B1 deficiency. PMID:27301931

  10. Foothills Parkway Section 8B Final Environmental Report, Volume 1

    Blasing, T.J.; Cada, G.F.; Carer, M.; Chin, S.M.; Dickerman, J.A.; Etnier, D.A.; Gibson, R.; Harvey, M.; Hatcher, B.; Lietzske, D.; Mann, L.K.; Mulholland, P.J.; Petrich, C.H.; Pounds, L.; Ranney, J.; Reed, R.M.; Ryan, P.F.; Schweitzer, M.; Smith, D.; Thomason, P.; Wade, M.C.

    1999-07-01

    In 1994, Oak Ridge National Laboratory (ORNL) was tasked by the National Park Service (NPS) to prepare an Environmental Report (ER) for Section 8B of the Foothills Parkway in the Great Smoky Mountains National Park (GSMNP). Section 8B represents 27.7 km (14.2 miles) of a total of 115 km (72 miles) of the planned Foothills Parkway and would connect the Cosby community on the east to the incorporated town of Pittman Center to the west.

  11. Lower Ionosphere Response to Solar Activity Forcing

    Laštovička, Jan

    Mysore, 2012. C1.1-61-12/1035. [COSPAR Scientific Assembly /39./. 14.07.2012-22.07.2012, Mysore] R&D Projects: GA MŠk LD12070 Institutional support: RVO:68378289 Keywords : Lower ionosphere * solar activity Subject RIV: DG - Athmosphere Sciences, Meteorology https://www.cospar-assembly.org/abstractcd/COSPAR-12/abstracts/C2.3-0010-12.pdf

  12. Thermal cyclotron radiation from solar active regions

    Various frequency spectra with the fine structure resulting from the thermal cyclotron radio emission from solar active regions are discussed. The conditions in sources (distribution of magnetic field and kinetic temperature over the height) are put forward which provide the frequency spectrum as a set of cyclotron lines and high frequency cut-offs. For each kind of distribution the frequency spectrum and polarization are of peculiar character. This permits one to find the conditions in the source through the properties of the observed microwave solar radio emission. To obtain reliable data on the fine structure and judge about conditions in the sources it is necessary to study microwave solar radio emission using the swept-frequency or multi-channel receivers combined with high directional antennae. (Auth.)

  13. Total Solar Irradiance Variability and the Solar Activity Cycle

    Raychaudhuri, Probhas

    2006-01-01

    It is suggested that the solar variability is due to the perturbed nature of the solar core and this variability is provided by the variability of the solar neutrino flux from the solar neutrino detectors i.e., Homestake, Superkamiokande, SAGE and GALLEX-GNO. The solar neutrino flux in the standard solar model (SSM) was calculated on the assumption of L_nu (neutrino luminosity) = L_gamma (optical luminosity) which implies that if there is a change in optical luminosity then solar neutrino flu...

  14. Frequency of coronal transients and solar activity

    The High Altitude Observatory's white light coronagraph aboard Skylab observed some 110 coronal transients - rapid changes in appearance of the corona - during its 227 days of operation. The longitudes of the origins of these transients were not distributed uniformly around the solar surface (51 of the 100 events observed in seven solar rotations arose from a single quadrant of longitude). Further, the frequency of transient production from each segment of the solar surface was well correlated with the sunspot number and Ca II plage (area x brightness) index in the segment, rotation by rotation. This correlation implies that transients occur more often above strong photospheric and chromospheric magnetic fields, that is, in regions where the coronal magnetic field is stronger and, perhaps, more variable. This pattern of occurrence is consistent with the belief that the forces propelling transient material outward are, primarily, magnetic. A quantitative relation between transient production from an area and the Zuerich sunspot number appropriate to that area is derived, and it is speculated that the relation is independent of phase in the solar activity cycle. If true, the Sun may give rise to as many as 100 white light coronal transients per month at solar cycle maximum. (Auth.)

  15. The Heliosphere Through the Solar Activity Cycle

    Balogh, A.; Lanzerotti, L. J.; Suess, S. T.

    2006-01-01

    Understanding how the Sun changes though its 11-year sunspot cycle and how these changes affect the vast space around the Sun the heliosphere has been one of the principal objectives of space research since the advent of the space age. This book presents the evolution of the heliosphere through an entire solar activity cycle. The last solar cycle (cycle 23) has been the best observed from both the Earth and from a fleet of spacecraft. Of these, the joint ESA-NASA Ulysses probe has provided continuous observations of the state of the heliosphere since 1990 from a unique vantage point, that of a nearly polar orbit around the Sun. Ulysses results affect our understanding of the heliosphere from the interior of the Sun to the interstellar medium - beyond the outer boundary of the heliosphere. Written by scientists closely associated with the Ulysses mission, the book describes and explains the many different aspects of changes in the heliosphere in response to solar activity. In particular, the authors describe the rise in solar ESA and NASA have now unamiously agreed a third extension to operate the highly successful Ulysses spacecraft until March 2008 and, in 2007 and 2008, the European-built space probe will fly over the poles of the Sun for a third time. This will enable Ulysses to add an important chapter to its survey of the high-latitude heliosphere and this additional material would be included in a 2nd edition of this book.

  16. Coronal Activity and Extended Solar Cycles

    Altrock, R. C.

    2012-12-01

    Wilson et al. (1988, Nature 333, 748) discussed a number of solar parameters, which appear at high latitudes and gradually migrate towards the equator, merging with the sunspot "butterfly diagram". They found that this concept had been identified by earlier investigators extending back to 1957. They named this process the "Extended Solar Cycle" (ESC). Altrock (1997, Solar Phys. 170, 411) found that this process continued in Fe XIV 530.3 nm emission features. In cycles 21 - 23 solar maximum occurred when the number of Fe XIV emission regions per day > 0.19 (averaged over 365 days and both hemispheres) first reached latitudes 18°, 21° and 21°, for an average of 20° ± 1.7°. Other recent studies have shown that Torsional Oscillation (TO) negative-shear zones are co-located with the ESC from at least 50° down to the equator and also in the zones where the Rush to the Poles occur. These phenomena indicate that coronal activity occurring up to 50° and higher latitudes is related to TO shear zones, another indicator that the ESC is an important solar process. Another high-latitude process, which appears to be connected with the ESC, is the "Rush to the Poles" ("Rush") of polar crown prominences and their associated coronal emission, including Fe XIV. The Rush is is a harbinger of solar maximum (cf. Altrock, 2003, Solar Phys. 216, 343). Solar maximum in cycles 21 - 23 occurred when the center line of the Rush reached a critical latitude. These latitudes were 76°, 74° and 78°, respectively, for an average of 76° ± 2°. Applying the above conclusions to Cycle 24 is difficult due to the unusual nature of this cycle. Cycle 24 displays an intermittent "Rush" that is only well-defined in the northern hemisphere. In 2009 an initial slope of 4.6°/yr was found in the north, compared to an average of 9.4 ± 1.7 °/yr in the previous three cycles. This early fit to the Rush would have reached 76° at 2014.6. However, in 2010 the slope increased to 7.5°/yr (an increase

  17. Division E Commission 10: Solar Activity

    Schrijver, Carolus J.; Fletcher, Lyndsay; van Driel-Gesztelyi, Lidia; Asai, Ayumi; Cally, Paul S.; Charbonneau, Paul; Gibson, Sarah E.; Gomez, Daniel; Hasan, Siraj S.; Veronig, Astrid M.; Yan, Yihua

    2016-04-01

    After more than half a century of community support related to the science of ``solar activity'', IAU's Commission 10 was formally discontinued in 2015, to be succeeded by C.E2 with the same area of responsibility. On this occasion, we look back at the growth of the scientific disciplines involved around the world over almost a full century. Solar activity and fields of research looking into the related physics of the heliosphere continue to be vibrant and growing, with currently over 2,000 refereed publications appearing per year from over 4,000 unique authors, publishing in dozens of distinct journals and meeting in dozens of workshops and conferences each year. The size of the rapidly growing community and of the observational and computational data volumes, along with the multitude of connections into other branches of astrophysics, pose significant challenges; aspects of these challenges are beginning to be addressed through, among others, the development of new systems of literature reviews, machine-searchable archives for data and publications, and virtual observatories. As customary in these reports, we highlight some of the research topics that have seen particular interest over the most recent triennium, specifically active-region magnetic fields, coronal thermal structure, coronal seismology, flares and eruptions, and the variability of solar activity on long time scales. We close with a collection of developments, discoveries, and surprises that illustrate the range and dynamics of the discipline.

  18. Analysis of Human TAAR8 and Murine Taar8b Mediated Signaling Pathways and Expression Profile

    Jessica Mühlhaus

    2014-11-01

    Full Text Available The thyroid hormone derivative 3-iodothyronamine (3-T1AM exerts metabolic effects in vivo that contradict known effects of thyroid hormones. 3-T1AM acts as a trace amine-associated receptor 1 (TAAR1 agonist and activates Gs signaling in vitro. Interestingly, 3-T1AM-meditated in vivo effects persist in Taar1 knockout-mice indicating that further targets of 3-T1AM might exist. Here, we investigated another member of the TAAR family, the only scarcely studied mouse and human trace-amine-associated receptor 8 (Taar8b, TAAR8. By RT-qPCR and locked-nucleic-acid (LNA in situ hybridization, Taar8b expression in different mouse tissues was analyzed. Functionally, we characterized TAAR8 and Taar8b with regard to cell surface expression and signaling via different G-protein-mediated pathways. Cell surface expression was verified by ELISA, and cAMP accumulation was quantified by AlphaScreen for detection of Gs and/or Gi/o signaling. Activation of G-proteins Gq/11 and G12/13 was analyzed by reporter gene assays. Expression analyses revealed at most marginal Taar8b expression and no gender differences for almost all analyzed tissues. In heart, LNA-in situ hybridization demonstrated the absence of Taar8b expression. We could not identify 3-T1AM as a ligand for TAAR8 and Taar8b, but both receptors were characterized by a basal Gi/o signaling activity, a so far unknown signaling pathway for TAARs.

  19. Analysis of Human TAAR8 and Murine Taar8b Mediated Signaling Pathways and Expression Profile

    Mühlhaus, Jessica; Dinter, Juliane; Nürnberg, Daniela; Rehders, Maren; Depke, Maren; Golchert, Janine; Homuth, Georg; Yi, Chun-Xia; Morin, Silke; Köhrle, Josef; Brix, Klaudia; Tschöp, Matthias; Kleinau, Gunnar; Biebermann, Heike

    2014-01-01

    The thyroid hormone derivative 3-iodothyronamine (3-T1AM) exerts metabolic effects in vivo that contradict known effects of thyroid hormones. 3-T1AM acts as a trace amine-associated receptor 1 (TAAR1) agonist and activates Gs signaling in vitro. Interestingly, 3-T1AM-meditated in vivo effects persist in Taar1 knockout-mice indicating that further targets of 3-T1AM might exist. Here, we investigated another member of the TAAR family, the only scarcely studied mouse and human trace-amine-associated receptor 8 (Taar8b, TAAR8). By RT-qPCR and locked-nucleic-acid (LNA) in situ hybridization, Taar8b expression in different mouse tissues was analyzed. Functionally, we characterized TAAR8 and Taar8b with regard to cell surface expression and signaling via different G-protein-mediated pathways. Cell surface expression was verified by ELISA, and cAMP accumulation was quantified by AlphaScreen for detection of Gs and/or Gi/o signaling. Activation of G-proteins Gq/11 and G12/13 was analyzed by reporter gene assays. Expression analyses revealed at most marginal Taar8b expression and no gender differences for almost all analyzed tissues. In heart, LNA-in situ hybridization demonstrated the absence of Taar8b expression. We could not identify 3-T1AM as a ligand for TAAR8 and Taar8b, but both receptors were characterized by a basal Gi/o signaling activity, a so far unknown signaling pathway for TAARs. PMID:25391046

  20. Cosmic rays, solar activity and the climate

    Although it is generally believed that the increase in the mean global surface temperature since industrialization is caused by the increase in green house gases in the atmosphere, some people cite solar activity, either directly or through its effect on cosmic rays, as an underestimated contributor to such global warming. In this letter a simplified version of the standard picture of the role of greenhouse gases in causing the global warming since industrialization is described. The conditions necessary for this picture to be wholly or partially wrong are then introduced. Evidence is presented from which the contributions of either cosmic rays or solar activity to this warming is deduced. The contribution is shown to be less than 10% of the warming seen in the twentieth century. (letter)

  1. Long-term variations of solar activity

    2007-01-01

    Using the Lomb-Scargle periodogram we analyzed two sunspot series: the one over the past 11000 years at the 10-year interval based upon the survey data of 14C concentration in tree-rings, reconstructed by Solanki et al.; and the sunspot number over the past 7000 years, derived from geomagnetic variations by Usoskin et al. We found the periods and quasi-periods in solar activity, such as about 225, 352, 441, 522 and 561 a, and near 1000 and 2000 a. An approach of wavelet transform was applied to check the two sunspot time series, with emphasis on investigating time-varying characteristics in the long-term fluctuations of solar activity. The results show that the lengths and amplitudes of the periods have changed with time, and large variations have taken place during some periods.

  2. Cosmic rays, solar activity and the climate

    Sloan, T.; Wolfendale, A. W.

    2013-12-01

    Although it is generally believed that the increase in the mean global surface temperature since industrialization is caused by the increase in green house gases in the atmosphere, some people cite solar activity, either directly or through its effect on cosmic rays, as an underestimated contributor to such global warming. In this letter a simplified version of the standard picture of the role of greenhouse gases in causing the global warming since industrialization is described. The conditions necessary for this picture to be wholly or partially wrong are then introduced. Evidence is presented from which the contributions of either cosmic rays or solar activity to this warming is deduced. The contribution is shown to be less than 10% of the warming seen in the twentieth century.

  3. Active Longitude and Solar Flare Occurrences

    Gyenge, N; Baranyi, T

    2015-01-01

    The aim of the present work is to specify the spatio-temporal characteristics of flare activity observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and Geostationary Operational Environmental Satellite (GOES) satellites in connection with the behaviour of the longitudinal domain of enhanced sunspot activity known as active longitude (AL). By using our method developed for this purpose, we identified the AL in every Carrington Rotation provided by the Debrecen Photoheliographic Data (DPD). The spatial probability of flare occurrence has been estimated depending on the longitudinal distance from AL in the northern and southern hemispheres separately. We have found that more than the 60\\% of the RHESSI and GOES flares is located within $\\pm 36^{\\circ}$ from the active longitude. Hence, the most flare-productive active regions tend to be located in or close to the active longitudinal belt. This observed feature may allow predicting the geo-effective position of the domain of enhanced fla...

  4. Phospholipase D2 mediates signaling by ATPase class I type 8B membrane 1[S

    Chen, Frank; Ghosh, Ayantika; Shneider, Benjamin L.

    2013-01-01

    Functional defects in ATPase class I type 8B membrane 1 (ATP8B1 or familial intrahepatic cholestasis 1, FIC1) lead to cholestasis by mechanism(s) that are not fully understood. One proposed pathophysiology involves aberrant signaling to the bile acid sensor, the farnesoid X receptor (FXR), via protein kinase C ζ (PKCζ). The following cell line-based studies investigated whether phospholipase D2 may transduce a signal from FIC1 to FXR. PLD2 gain of function led to activation of the bile salt e...

  5. Solar Eruptions Initiated in Sigmoidal Active Regions

    Savcheva, Antonia

    2016-07-01

    active regions that have been shown to possess high probability for eruption. They present a direct evidence of the existence of flux ropes in the corona prior to the impulsive phase of eruptions. In order to gain insight into their eruptive behavior and how they get destabilized we need to know their 3D magnetic field structure. First, we review some recent observations and modeling of sigmoidal active regions as the primary hosts of solar eruptions, which can also be used as useful laboratories for studying these phenomena. Then, we concentrate on the analysis of observations and highly data-constrained non-linear force-free field (NLFFF) models over the lifetime of several sigmoidal active regions, where we have captured their magnetic field structure around the times of major flares. We present the topology analysis of a couple of sigmoidal regions pointing us to the probable sites of reconnection. A scenario for eruption is put forward by this analysis. We demonstrate the use of this topology analysis to reconcile the observed eruption features with the standard flare model. Finally, we show a glimpse of how such a NLFFF model of an erupting region can be used to initiate a CME in a global MHD code in an unprecedented realistic manner. Such simulations can show the effects of solar transients on the near-Earth environment and solar system space weather.

  6. Conserved POU/OCT- and GATA-binding sites in 5'-flanking promoter region of mammalian WNT8B orthologs.

    Katoh, Masuko; Katoh, Masaru

    2007-05-01

    WNT family members are secreted-type glycoproteins regulating cell fate, planar cell polarity, cell adhesion, and cell movement. WNT signals are context-dependently transduced to the canonical pathway for the transcriptional up-regulation of MYC, CCND1, FGF20, JAG1, WISP1 and DKK1 genes, and also to the non-canonical pathway for the activation of RHOA, JNK, PKC, NFAT and NLK signaling cascades. We cloned and characterized the wild-type human WNT8B, while another group the aberrant human WNT8B with Gly230Ala and Arg284Leu amino-acid substitutions. Although WNT8B is undetectable in normal adult tissues by using Northern blot analyses, WNT8B is expressed in gastric cancer, pancreatic cancer, colorectal cancer, breast cancer, and embryonal tumors. Here, comparative integromics on WNT8B orthologs were investigated by using bioinformatics (Techint) and human intelligence (Humint). Cow Wnt8b gene was identified within NW_001494361.1 genome sequence. Predicted sequence XM_582222.3 was an artificial cow Wnt8b with aberrant prediction for the first exon. Cow Wnt8b complete coding sequence was found to encode a 350-amino-acid protein, which showed 96.9% total-amino-acid identity with human WNT8B. Comparative proteomics revealed that N-terminal signal peptide, 22 Cys residues, two Asn-linked glycosylation sites, Gly230, and Arg284 of human WNT8B were conserved among mammalian WNT8B orthologs. Comparative genomics revealed that POU/OCT- and GATA-binding sites in the 5'-flanking promoter region were conserved among human, chimpanzee, cow, mouse, and rat WNT8B orthologs. In silico expression analyses revealed that human WNT8B was expressed in embryoid body derived from embryonic stem (ES) cells, hepatocyte progenitors derived from ES cells, fetal brain, diffuse-type gastric cancer, colorectal cancer, prostate cancer, and ovarian fibrotheoma. Based on the expression profiles of POU and GATA family transcription factors, it was revealed that WNT8B expression in hepatocyte

  7. Solar Energy Education. Renewable energy activities for earth science

    1980-01-01

    A teaching manual is provided to aid teachers in introducing renewable energy topics to earth science students. The main emphasis is placed on solar energy. Activities for the student include a study of the greenhouse effect, solar gain for home heating, measuring solar radiation, and the construction of a model solar still to obtain fresh water. Instructions for the construction of apparatus to demonstrate a solar still, the greenhouse effect and measurement of the altitude and azimuth of the sun are included. (BCS)

  8. The Heliosphere through the Solar Activity Cycle

    Balogh, André; Suess, Steven T

    2008-01-01

    Understanding how the Sun changes though its 11-year sunspot cycle and how these changes affect the vast space around the Sun – the heliosphere – has been one of the principal objectives of space research since the advent of the space age. This book presents the evolution of the heliosphere through an entire solar activity cycle. The last solar cycle (cycle 23) has been the best observed from both the Earth and from a fleet of spacecraft. Of these, the joint ESA-NASA Ulysses probe has provided continuous observations of the state of the heliosphere since 1990 from a unique vantage point, that of a nearly polar orbit around the Sun. Ulysses’ results affect our understanding of the heliosphere from the interior of the Sun to the interstellar medium - beyond the outer boundary of the heliosphere. Written by scientists closely associated with the Ulysses mission, the book describes and explains the many different aspects of changes in the heliosphere in response to solar activity. In particular, the authors...

  9. Influence of solar activity on Jupiter's atmosphere

    Vidmachenko, A. P.

    2016-05-01

    The influx of solar energy to different latitudes while Jupiter's orbital motion around the Sun varies significantly. This leads to a change in the optical and physical characteristics of its atmosphere. Analysis of the data for 1850-1991 on determination of the integral magnitude Mj Jupiter in the V filter, and a comparison with the changes of the Wolf numbers W, characterizing the variations of solar activity (SA) - showed that the change of Mj in maxima of the SA - has minima for odd, and maximums - for the even of SA cycles. That is, changing of the Jupiter brightness in visible light is much evident 22.3-year magnetic cycle, and not just about the 11.1-year cycle of solar activity. Analysis of the obtained in 1960-2015 data on the relative distribution of brightness along the central meridian of Jupiter, for which we calculated the ratio of the brightness Aj of northern to the southern part of the tropical and temperate latitudinal zones, allowed to approximate the change of Aj by sinusoid with a period of 11.91±0.07 earth years. Comparison of time variation of Aj from changes in the index of SA R, and the movement of the planet in its orbit - indicates the delay of response of the visible cloud layer in the atmosphere of the Sun's exposure mode for 6 years. This value coincides with the radiative relaxation of the hydrogen-helium atmosphere

  10. 15 CFR 8b.21 - Treatment of students.

    2010-01-01

    ..., counseling, financial aid, physical education, athletics, recreation, transportation, other extracurricular, or other post secondary education aid, benefits, or services to which this subpart applies. (b) A... Secondary Education § 8b.21 Treatment of students. (a) General. No qualified handicapped student shall,...

  11. Tsunami related to solar and geomagnetic activity

    Cataldi, Gabriele; Cataldi, Daniele; Straser, Valentino

    2016-04-01

    The authors of this study wanted to verify the existence of a correlation between earthquakes of high intensity capable of generating tsunami and variations of solar and Earth's geomagnetic activity. To confirming or not the presence of this kind of correlation, the authors analyzed the conditions of Spaceweather "near Earth" and the characteristics of the Earth's geomagnetic field in the hours that preceded the four earthquakes of high intensity that have generated tsunamis: 1) Japan M9 earthquake occurred on March 11, 2011 at 05:46 UTC; 2) Japan M7.1 earthquake occurred on October 25, 2013 at 17:10 UTC; 3) Chile M8.2 earthquake occurred on April 1, 2014 at 23:46 UTC; 4) Chile M8.3 earthquake occurred on September 16, 2015 at 22:54 UTC. The data relating to the four earthquakes were provided by the United States Geological Survey (USGS). The data on ion density used to realize the correlation study are represented by: solar wind ion density variation detected by ACE (Advanced Composition Explorer) Satellite, in orbit near the L1 Lagrange point, at 1.5 million of km from Earth, in direction of the Sun. The instrument used to perform the measurement of the solar wind ion density is the Electron, Proton, and Alpha Monitor (EPAM) instrument, equipped on the ACE Satellite. To conduct the study, the authors have taken in consideration the variation of the solar wind protons density of three different energy fractions: differential proton flux 1060-1900 keV (p/cm^2-sec-ster-MeV); differential proton flux 761-1220 keV (p/cm^2-sec-ster-MeV); differential proton flux 310-580 keV (p/cm^2-sec-ster-MeV). Geomagnetic activity data were provided by Tromsø Geomagnetic Observatory (TGO), Norway; by Scoresbysund Geomagnetic Observatory (SCO), Greenland, Denmark and by Space Weather Prediction Center of Pushkov Institute of terrestrial magnetism, ionosphere and radio wave propagation (IZMIRAN), Troitsk, Moscow Region. The results of the study, in agreement with what already

  12. Preferred longitudes in solar and stellar activity

    Berdyugina, S. V.

    An analysis of the distribution of starspots on the surfaces of very active stars, such as RS CVn- FK Com-type stars as well as young solar analogs, reveals preferred longitudes of spot formation and their quasi-periodic oscillations, i.e. flip-flop cycles. A non-linear migration of the preferred longitudes suggests the presence of the differential rotation and variations of mean spot latitudes. It enables recovering stellar butterfly diagrams. Such phenomena are found to persist in the sunspot activity as well. A comparison of the observed properties of preferred longitudes on the Sun with those detected on more active stars leads to the conclusion that we can learn fine details of the stellar dynamo by studying the Sun, while its global parameters on the evolutionary time scale are provided by a sample of active stars.

  13. Searches for high frequency variations in the 8-B neutrino flux at the Sudbury neutrino observatory

    We have peformed three searches for high-frequency signals in the solar neutrino flux measured by the Sudbury Neutrino Observatory (SNO), motivated by the possibility that solar g-mode oscillations could affect the production or propagation of solar 8B neutrinos. The first search looked for any significant peak in the frequency range l/day to 144/day, with a sensitivity to sinusoidal signals with amplitudes of 12% or greater. The second search focused on regions in which g-mode signals have been claimed by experiments aboard the SoHO satellite, and was sensitive to signals with amplitudes of 10% or greater. The third search looked for extra power across the entire frequency band. No statistically significant signal was detected in any of the three searches.

  14. Searches for high frequency variations in the 8-B neutrino flux at the Sudbury neutrino observatory

    Rielage, Keith [Los Alamos National Laboratory; Seibert, Stanley R [Los Alamos National Laboratory; Hime, Andrew [Los Alamos National Laboratory; Elliott, Steven R [Los Alamos National Laboratory; Stonehill, L C [Los Alamos National Laboratory; Wouters, J M [Los Alamos National Laboratory; Aharmim, B [LAURENTIAN UNIV; Ahmed, S N [QUEEN' S UNIV; Anthony, A E [UNIV OF TEXAS; Barros, N [PORTUGAL; Beier, E W [UNIV OF PA; Bellerive, A [CARLETON UNIV; Belttran, B [UNIV OF ALBERTA; Bergevin, M [LBNL; Biller, S D [UNIV OF OXFORD; Boudjemline, K [CARLETON UNIV; Burritt, T H [UNIV OF WASHINGTON; Cai, B [QUEEN' S UNIV; Chan, Y D [LBNL; Chauhan, D [LAURENTIAN UNIV; Chen, M [QUEEN' S UNIV; Cleveland, B T [UNIV OF OXFORD; Cox - Mobrand, G A [UNIV OF WASHINGTON; Dai, X [QUEEN' S UNIV; Deng, H [UNIV OF PA; Detwiler, J [LBNL; Dimarco, M [QUEEN' S UNIV; Doe, P J [UNIV OF WASHINGTON; Drouin, P - L [CARLTON UNIV; Duba, C A [UNIV OF WASHINGTON; Duncan, F A [SNOLAB, SUDBURY; Dunford, M [UNIV OF PA; Earle, E D [QUEEN' S UNIV; Evans, H C [QUEEN' S UNIV; Ewan, G T [QUEEN' S UNIV; Farine, J [LAURENTTIAN UNIV; Fergani, H [UNIV OF OXFORD; Fleurot, F [LAURENTIAN UNIV; Ford, R J [SNOLAB, SUDBURY; Formaggilo, J A [MASSACHUSETTS INST. OF TECH.; Gagnon, N [UNIV OF WASHINGTON; Goon, J Tm [LOUISIANA STATE UNIV; Guillian, E [QUEEN' S UNIV; Habib, S [UNIV OF ALBERTA; Hahn, R L [BNL; Hallin, A L [UNIV OF ALBERTA; Hallman, E D [LAURENTIAN UNIV; Harvey, P J [QUEEN' S UNIV; Hazama, R [UNIV OF WASHINGTON; Heintzelman, W J [UNIV OF PA; Heise, J [SNOLAB, SUDBURY; Helmer, R L [TRIUMF; Howard, C [UNIV OF ALBERTA; Howe, M A [UNIV OF WASHINGTON; Huang, M [UNIV OF TEXAS; Jamieson, B [UNIV OF BRITISH COLUMBIA; Jelley, N A [UNIV OF OXFORD; Keeter, K J [SNOLAB, SUDBURY; Klein, J R [UNIV OF TEXAS; Kos, M [QUEEN' S UNIV; Kraus, C [QUEEN' S UNIV; Krauss, C B [UNIV OF ALBERTA; Kutter, T [LOUISIANA STATE UNIV; Kyba, C C M [UNIV OF PA; Law, J [UNIV OF GUELPH; Lawson, I T [SNOLAB, SUDBURY; Lesko, K T [LBNL; Leslie, J R [QUEEN' S UNIV; Loach, J C [UNIV OF OXFORD; Maclellan, R [QUEEN' S UNIV; Majerus, S [UNIV OF OXFORD; Mak, H B [QUEEN' S UNIV; Maneira, J [PORTUGAL; Martin, R [QUEEN' S UNIV; Mccauley, N [UNIV OF PA; Mc Donald, A B [QUEEN' S UNIV; Mcgee, S [UNIV OF WASHINGTON; Miffin, C [CARLETON UNIV; Miller, M L [MASSACHUSETTS INST. OF TECH.; Monreal, B [MASSACHUSETTS INST. OF TECH.; Monroe, J [MASSACHUSETTS INST. OF TECH; Morissette, B [SNOLAB, SUDBURY; Nickel, B G [UNIV OF GUELPH; Noble, A J [QUEEN' S UNIV; O' Keeffe, H M [UNIV OF OXFORD; Oblath, N S [UNIV OF WASHINGTON; Orebi Gann, G D [UNIV OF OXFORD; Oser, S M [UNIV OF BRITISH COLUMBIA; Ott, R A [MASSACHUSETTS INST. OF TECH.; Peeters, S J M [UNIV OF OXFORD; Poon, A W P [LBNL; Prior, G [LBNL; Reitzner, S D [UNIV OF GUELPH; Robertson, B C [QUEEN' S UNIV; Robertson, R G H [UNIV OF WASHINGTON; Rollin, E [CARLETON UNIV; Schwendener, M H [LAURENTIAN UNIV; Secrest, J A [UNIV OF PA; Seibert, S R [UNIV OF TEXAS; Simard, O [CARLETON UNIV; Sinclair, D [CARLETON UNIV; Sinclair, L [CARLETON UNIV; Skensved, P [QUEEN' S UNIV; Sonley, T J [MASSACHUSETTS INST. OF TECH.; Tesic, G [CARLETON UNIV; Tolich, N [UNIV OF WASHINGTON; Tsui, T [UNIV OF BRITISH COLUMBIA; Tunnell, C D [UNIV OF TEXAS; Van Berg, R [UNIV OF PA; Van Devender, B A [UNIV OF WASHINGTON; Virtue, C J [LAURENTIAN UNIV; Wall, B L [UNIV OF WASHINGTON; Waller, D [CARLETON UNIV; Wan Chan Tseung, H [UNIV OF OXFORD; West, N [UNIV OF OXFORD; Wilkerson, J F [UNIV OF WASHINGTON; Wilson, J R [UNIV OF OXFORD; Wright, A [QUEEN' S UNIV; Yeh, M [BNL; Zhang, F [CARLETON UNIV; Zuber, K [UNIV OF OXFORD

    2009-01-01

    We have peformed three searches for high-frequency signals in the solar neutrino flux measured by the Sudbury Neutrino Observatory (SNO), motivated by the possibility that solar g-mode oscillations could affect the production or propagation of solar {sup 8}B neutrinos. The first search looked for any significant peak in the frequency range l/day to 144/day, with a sensitivity to sinusoidal signals with amplitudes of 12% or greater. The second search focused on regions in which g-mode signals have been claimed by experiments aboard the SoHO satellite, and was sensitive to signals with amplitudes of 10% or greater. The third search looked for extra power across the entire frequency band. No statistically significant signal was detected in any of the three searches.

  15. Transient flows of the solar wind associated with small-scale solar activity in solar minimum

    Slemzin, Vladimir; Veselovsky, Igor; Kuzin, Sergey; Gburek, Szymon; Ulyanov, Artyom; Kirichenko, Alexey; Shugay, Yulia; Goryaev, Farid

    The data obtained by the modern high sensitive EUV-XUV telescopes and photometers such as CORONAS-Photon/TESIS and SPHINX, STEREO/EUVI, PROBA2/SWAP, SDO/AIA provide good possibilities for studying small-scale solar activity (SSA), which is supposed to play an important role in heating of the corona and producing transient flows of the solar wind. During the recent unusually weak solar minimum, a large number of SSA events, such as week solar flares, small CMEs and CME-like flows were observed and recorded in the databases of flares (STEREO, SWAP, SPHINX) and CMEs (LASCO, CACTUS). On the other hand, the solar wind data obtained in this period by ACE, Wind, STEREO contain signatures of transient ICME-like structures which have shorter duration (<10h), weaker magnetic field strength (<10 nT) and lower proton temperature than usual ICMEs. To verify the assumption that ICME-like transients may be associated with the SSA events we investigated the number of weak flares of C-class and lower detected by SPHINX in 2009 and STEREO/EUVI in 2010. The flares were classified on temperature and emission measure using the diagnostic means of SPHINX and Hinode/EIS and were confronted with the parameters of the solar wind (velocity, density, ion composition and temperature, magnetic field, pitch angle distribution of the suprathermal electrons). The outflows of plasma associated with the flares were identified by their coronal signatures - CMEs (only in few cases) and dimmings. It was found that the mean parameters of the solar wind projected to the source surface for the times of the studied flares were typical for the ICME-like transients. The results support the suggestion that weak flares can be indicators of sources of transient plasma flows contributing to the slow solar wind at solar minimum, although these flows may be too weak to be considered as separate CMEs and ICMEs. The research leading to these results has received funding from the European Union’s Seventh Programme

  16. Research programme 'Active Solar Energy Use - Solar Heating and Heat Storage'. Activities and projects 2003

    In this report by the research, development and demonstration (RD+D) programme coordinators the objectives, activities and main results in the area of solar heating and heat storage in Switzerland are presented for 2003. In a stagnating market environment the strategy of the Swiss Federal Office of Energy mainly consists in improving the quality and durability of solar collectors and materials, optimizing combisystems for space heating and domestic hot water preparation, searching for storage systems with a higher energy storage density than in the case of sensible heat storage in water, developing coloured solar collectors for more architectonic freedom, and finalizing a seasonal heat storage project for 100 dwellings to demonstrate the feasibility of solar fractions larger than 50% in apartment houses. Support was granted to the Swiss Testing Facility SPF in Rapperswil as in previous years; SPF was the first European testing institute to perform solar collector labeling according to the new rules of the 'Solar Keymark', introduced in cooperation with the European Committee for Standardization CEN. Several 2003 projects were conducted within the framework of the Solar Heating and Cooling Programme of the International Energy Agency IEA. Computerized simulation tools were improved. With the aim of jointly producing high-temperature heat and electric power a solar installation including a concentrating collector and a thermodynamic machine based on a Rankine cycle is still being developed. Seasonal underground heat storage was studied in detail by means of a validated computer simulation programme. Design guidelines were obtained for such a storage used in the summer time for cooling and in the winter time for space heating via a heat pump: depending on the ratio 'summer cooling / winter heating', cooling requires a cooling machine, or direct cooling without such a machine is possible. The report ends up with the list of all supported RD+D projects

  17. Solar Magnetism and the Activity Telescope at HSOS

    Hong-Qi Zhang; Ya-Nan Wang; Qi-Qian Hu; Jun-Sun Xue; Hai-Tian Lu; Hou-Kun Ni; Han-Liang Chen; Xiao-Jun Zhou; Qing-Sheng Zhu; Lü-Jun Yuan; Yong Zhu; Dong-Guang Wang; Yuan-Yong Deng; Ke-Liang Hu; Jiang-Tao Su; Jia-Ben Lin; Gang-Hua Lin; Shi-Mo Yang; Wei-Jun Mao

    2007-01-01

    A new solar telescope system is described, which has been operating at Huairou Solar Observing Station (HSOS), National Astronomical Observatories, Chinese Academy of Sciences (CAS), since the end of 2005. This instrument, the Solar Magnetism and Activity Telescope (SMAT), comprises two telescopes which respectively make measurements of full solar disk vector magnetic field and Hα observation. The core of the full solar disk video vector magnetograph is a birefringent filter with 0.1(A) bandpass, installed in the tele-centric optical system of the telescope. We present some preliminary observational results of the full solar disk vector magnetograms and Hα filtergrams obtained with this telescope system.

  18. Solar Energy Education. Industrial arts: student activities. Field test edition

    1981-02-01

    In this teaching manual several activities are presented to introduce students to information on solar energy through classroom instruction. Wind power is also included. Instructions for constructing demonstration models for passive solar systems, photovoltaic cells, solar collectors and water heaters, and a bicycle wheel wind turbine are provided. (BCS)

  19. Methods of computational topology for Solar Activity forecasting (Extended abstract)

    Knyazeva, Irina; Makarenko, Nikolay; Malkova, Daria

    2015-01-01

    Solar activity is a space-time complex of events which produced by the Sun magnetic fields. One of the results of this activity is a huge plasma ejection which called solar flares. The solar flares occurs mainly in the areas with an especially strong magnetic fields called Active Regions (AR). Observation phenomenology indicates that significant change in the magnetic field topology precede the strong flares. We investigated changes in topology by the methods of computational topology. For th...

  20. ANATOMY OF SOLAR CYCLE LENGTH AND SUNSPOT NUMBER: DEPENDENCE OF AVERAGE GLOBAL TEMPERATURE ON SOLAR ACTIVITY

    A. B. BHATTACHARYA

    2011-11-01

    Full Text Available The paper examines thoroughly all the past 23 sunspot cycles and the associated 11 hale cycles. It is noticed that solar cycle 23 had a deep minimum with longest decline phase. When solar cycles 20 to 23 are compared with solar cycles 1 to 4, the forthcoming Dalton minimum can be expected. The predicted variation of sunspot number for the present solar cycle 24 is examined at length and it appears that the peak monthly sunspot number of the solar cycle 24 will be around 80. We have correlated the solar cycle length and peak sunspot number witha priority to the solar cycle 24. From an elaborate analysis it appears that the most common cycle length is around 10.5 years, with few cycles in the range 11.5 to 12.5 years. Global temperature depends upon the total solar irradiance which in turn depends on duration of solar cycle. Also cloud cover directly depends on the solar irradiance. Our analysis supports that the global temperature is governed by the length of the predicted cycle.From the increased length of solar cycle 23, we have estimated the temperature variation of cycle 24. The predicted result reassures that average global temperature will be decreased for next few solar cycles due totypical solar activity. The results have been interpreted emphasizing the formation of type III solar radio bursts caused by plasma excitation.

  1. Solar wind turbulence as a driver of geomagnetic activity

    Ikechukwu Ugwu, Ernest Benjamin; Nneka Okeke, Francisca; Ugonabo, Obiageli Josephine

    2016-07-01

    We carried out simultaneous analyses of interplanetary and geomagnetic datasets for the period of (solar Maunder) least (2009) and maximum (2002) solar activity to determine the nature of solar wind turbulence on geomagnetic activity using AE, ASY-D, and ASY-H indices. We determined the role played by Alfvénic fluctuations in the solar wind so as to find out the nature of the turbulence. Our analyses showed that solar wind turbulence play a role in geomagnetic processes at high latitudes during periods of low and high solaractivity but does not have any effect at mid-low latitudes.

  2. Solar Activity Studies using Microwave Imaging Observations

    Gopalswamy, N.

    2016-01-01

    We report on the status of solar cycle 24 based on polar prominence eruptions (PEs) and microwave brightness enhancement (MBE) information obtained by the Nobeyama radioheliograph. The north polar region of the Sun had near-zero field strength for more than three years (2012-2015) and ended only in September 2015 as indicated by the presence of polar PEs and the lack of MBE. The zero-polar-field condition in the south started only around 2013, but it ended by June 2014. Thus the asymmetry in the times of polarity reversal switched between cycle 23 and 24. The polar MBE is a good proxy for the polar magnetic field strength as indicated by the high degree of correlation between the two. The cross-correlation between the high- and low-latitude MBEs is significant for a lag of approximately 5.5 to 7.3 years, suggesting that the polar field of one cycle indicates the sunspot number of the next cycle in agreement with the Babcock-Leighton mechanism of solar cycles. The extended period of near-zero field in the north-polar region should result in a weak and delayed sunspot activity in the northern hemisphere in cycle 25.

  3. Magnetic history of solar active regions

    An attempt was made to use recent magnetic observations to trace the history of a typical solar active region from birth to death. By comparing the short-term motions to the long-term spreading, it is demonstrated that the decay process is dominated, over periods ranging from days to months, by a random walk of field lines, with a diffusion constant of roughly 200 to 400 km2/sec. While the interaction between diffusion and differential rotation dictates the geometric pattern of the decaying region, the actual quantity of surviving flux appears to be less, and its ultimate annihilation more thorough, than would have been expected. This probably indicates a continued subsurface coupling between opposite polarity features. In addition, the long-range agreement between theory and observation is considerably improved by postulating the existence, in the middle latitudes of each hemisphere, of a systematic, poleward-moving meridional flow of about 3 m/sec. The outlook for being able to make continued progress towards the understanding of basic solar phenomena by further efforts in this direction is promising

  4. Solar active regions: a nonparametric statistical analysis

    Pelt, J; Tuominen, I

    2009-01-01

    The sunspots and other solar activity indicators tend to cluster on the surface of the Sun.These clusters very often occur at certain longitudes that persist in time.It is of general interest to find new and simple ways to characterize the observed distributions of different indicators and their behaviour in time. In the present work we use Greenwich sunspot data to evaluate statistical but not totally coherent stability of sunspot distribution along latitudes as well as longitudes. The aim was to obtain information on the longitudinal distribution of the underlying spot-generating mechanism rather than on the distribution and migration of sunspots or sunspot groups on the solar surface. Therefore only sunspot groups were included in the analysis, and only the time of their first appearance was used. We use simple nonparametric approach to reveal sunspot migration patterns and their persistency. Our analysis shows that regions where spots are generated tend to rotate differentially as the spots and spot group...

  5. Usability of solar radius variations as an indicator of solar activity and influence on climate

    Kilcik, A.; Golbasi, O.; Kilic, H.; Ozkan, V.; Yuceer, A. Y.

    In this study we investigated whether the solar semi-diameter could be treated as an indicator of solar activity. We applied the cross-correlation method to show the agreement of solar radius data with solar irradiance measurements. We used the solar semi-diameter data obtained from astrolabe observations at TUBITAK National Observatory (TUG) / Turkey and at Cote d'Azur Observatory (OCA)/France. We treated the regional air surface temperature measured in Antalya/Turkey as a climate indicator. Result of our analyses, indicates a considerable correlation (-0.63) between the solar radius and solar irradiance measurements. In addition, a comparison of solar radius and regional temperature values indicated that there is an acceptable correlative and periodical agreement between the two quantities.

  6. Nuclear Interference effects in 8B sub-Coulomb breakup

    Nunes, F. M.; Thompson, I.J.

    1998-01-01

    The breakup of $^8$B on $^{58}$Ni below the Coulomb barrier was measured recently with the aim of determining the Coulomb breakup components. We reexamine this reaction, and perform one step quantum-mechanical calculations that include E1, E2 and nuclear contributions. We show that the nuclear contribution is by no means negligible at the intermediate angular range where data was taken. Our results indicate that, for an accurate description of this reaction, Coulomb E1, E2 and nuclear process...

  7. Active Vibration Damping of Solar Arrays

    Reinicke, Gunar; Baier, Horst; Grillebeck, Anton; Scharfeld, Frank; Hunger, Joseph; Abou-El-Ela, A.; Lohberg, Andreas

    2012-07-01

    Current generations of large solar array panels are lightweight and flexible constructions to reduce net masses. They undergo strong vibrations during launch. The active vibration damping is one convenient option to reduce vibration responses and limit stresses in facesheets. In this study, two actuator concepts are used for vibration damping. A stack interface actuator replaces a panel hold down and is decoupled from bending moments and shear forces. Piezoelectric patch actuators are used as an alternative, where the number, position and size of actuators are mainly driven by controllability analyses. Linear Quadratic Gaussian control is used to attenuate vibrations of selected mode shapes with both actuators. Simulations as well as modal and acoustic tests show the feasibility of selected actuator concepts.

  8. Revisiting the question: Does high-latitude solar activity lead low-latitude solar activity in time phase?

    Cross-correlation analysis and wavelet transform methods are used to investigate whether high-latitude solar activity leads low-latitude solar activity in time phase or not, using the data of the Carte Synoptique solar filaments archive from 1919 March to 1989 December. From the cross-correlation analysis, high-latitude solar filaments have a time lead of 12 Carrington solar rotations with respect to low-latitude ones. Both the cross-wavelet transform and wavelet coherence indicate that high-latitude solar filaments lead low-latitude ones in time phase. Furthermore, low-latitude solar activity is better correlated with high-latitude solar activity of the previous cycle than with that of the following cycle, which is statistically significant. Thus, the present study confirms that high-latitude solar activity in the polar regions is indeed better correlated with the low-latitude solar activity of the following cycle than with that of the previous cycle, namely, leading in time phase.

  9. Solar air-conditioning-active, hybrid and passive

    Yellott, J. I.

    1981-04-01

    After a discussion of summer air conditioning requirements in the United States, active, hybrid, and passive cooling systems are defined. Active processes and systems include absorption, Rankine cycle, and a small variety of miscellaneous systems. The hybrid solar cooling and dehumidification technology of desiccation is covered as well as evaporative cooling. The passive solar cooling processes covered include convective, radiative and evaporative cooling. Federal and state involvement in solar cooling is then discussed. (LEW)

  10. Relations between the solar inertial motion, solar activity and geomagnetic index aa since the year 1844

    Charvátová, Ivanka; Střeštík, Jaroslav

    2007-01-01

    Roč. 40, - (2007), s. 1026-1031. ISSN 0273-1177 R&D Projects: GA AV ČR(CZ) IAA300120608 Institutional research plan: CEZ:AV0Z30120515 Keywords : solar motion * solar activity * geomagnetic activity Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 0.774, year: 2007

  11. Low-lying non-normal parity states in 8B measured by proton elastic scattering on 7Be

    Yamaguchi, H; Amadio, G; Fujikawa, H; Teranishi, T; Saito, A; He, J J; Nishimura, S; Togano, Y; Kwon, Y K; Niikura, M; Iwasa, N; Inafuku, K; Khiem, L H

    2008-01-01

    A new measurement of proton resonance scattering on 7Be was performed up to the center-of-mass energy of 6.7 MeV using the low-energy RI beam facility CRIB (CNS Radioactive Ion Beam separator) at the Center for Nuclear Study of the University of Tokyo. The excitation function of 7Be+p elastic scattering above 3.5 MeV was measured successfully for the first time, providing important information about the resonance structure of the 8B nucleus. The resonances are related to the reaction rate of 7Be(p, gamma)8B, which is the key reaction in solar 8B neutrino production. Evidence for the presence of two negative parity states is presented. One of them is a 2- state observed as a broad s-wave resonance, the existence of which had been questionable. Its possible effects on the determination of the astrophysical S-factor of 7Be(p, gamma)8B at solar energy are discussed. The other state had not been observed in previous measurements, and its spin and parity were determined as 1-.

  12. Solar Activity, Different Geomagnetic Activity Levels and Acute Myocardial Infarction

    Dimitrova, Svetla; Jordanova, Malina; Stoilova, Irina; Taseva, Tatiana; Maslarov, Dimitar

    Results on revealing a possible relationship between solar activity (SA) and geomagnetic activity (GMA) and acute myocardial infarction (AMI) morbidity are presented. Studies were based on medical data covering the period from 1.12.1995 to 31.12.2004 and concerned daily distribution of patients with AMI diagnose (in total 1192 cases) from Sofia region on the day of admission at the hospital. Analysis of variance (ANOVA) was applied to check the significance of GMA intensity effect and the type of geomagnetic storms, those caused by Magnetic Clouds (MC) and by High Speed Solar Wind Streams (HSSWS), on AMI morbidity. Relevant correlation coefficients were calculated. Results revealed statistically significant positive correlation between considered GMA indices and AMI. ANOVA revealed that AMI number was signifi- cantly increased from the day before (-1st) till the day after (+1st) geomagnetic storms with different intensities. Geomagnetic storms caused by MC were related to significant increase of AMI number in comparison with the storms caused by HSSWS. There was a trend for such different effects even on -1st and +1st day.

  13. Can origin of the 2400-year cycle of solar activity be caused by solar inertial motion?

    I. Charvátová

    Full Text Available A solar activity cycle of about 2400 years has until now been of uncertain origin. Recent results indicate it is caused by solar inertial motion. First we describe the 178.7-year basic cycle of solar motion. The longer cycle, over an 8000 year interval, is found to average 2402.2 years. This corresponds to the Jupiter/Heliocentre/Barycentre alignments (9.8855 × 243. Within each cycle an exceptional segment of 370 years has been found characterized by a looping pattern by a trefoil or quasitrefoil geometry. Solar activity, evidenced by 14C tree-ring proxies, shows the same pattern. Solar motion is computable in advance, so this provides a basis for future predictive assessments. The next 370-year segment will occur between AD 2240 and 2610.

    Key words: Solar physics (celestial mechanics

  14. Size-Flux Relation in Solar Active Regions

    2003-01-01

    We present a study of the relationship between integral area and corre-sponding total magnetic flux for solar active regions. It is shown that some of theserelationships are satisfied to simple power laws. Fractal examination showed thatsome of these power laws can not be justified inside the simple models of stationarymagnetic flux tube aggregation. All magnetic fluxes and corresponding areas werecalculated using the data measured with the Solar Magnetic Field Telescope of theHuairou Solar Observing Station in Beijing.

  15. North South Asymmetry of Different Solar Activity Features During Solar Cycle 23

    Bankoti, Neeraj Singh; Pande, Seema; Pande, Bimal; Pandey, Kavita

    2009-01-01

    A study on North South (NS) asymmetry of different solar activity features (DSAF) such as solar proton events, solar active prominences, H alpha flare index, soft X ray flares, monthly mean sunspot area and monthly mean sunspot number were carried out from 1996 to 2008. It is found in our result that solar cycle 23 is magnetically weak compared to solar cycle 22. Study shows the Southern dominance of DSAF during the time period of study. During the rising phase of the cycle the numbers of DSAF approximately equal on the North and South Hemisphere. However, these activities tend to shift from Northern Hemisphere to Southern Hemisphere in between year 1998 to 1999. The statistical significance of the asymmetry time series using a chi square test of goodness of fit indicates that in most of the cases the asymmetry is highly significant, i.e., the asymmetry is a real feature in the NS distribution of DSAF.

  16. Observation of Hysteresis between Solar Activity Indicators and -mode Frequency Shifts for Solar Cycle 22

    S. C. Tripathy; Brajesh Kumar; Kiran Jain; A. Bhatnagar

    2000-09-01

    Using intermediate degree p-mode frequency data sets for solar cycle 22, we find that the frequency shifts and magnetic activity indicators show a ``hysteresis" phenomenon. It is observed that the magnetic indices follow different paths for the ascending and descending phases of the solar cycle while for radiative indices, the separation between the paths are well within the error limits.

  17. Annual DOE active solar heating and cooling contractors' review meeting. Premeeting proceedings and project summaries

    None,

    1981-09-01

    Ninety-three project summaries are presented which discuss the following aspects of active solar heating and cooling: Rankine solar cooling systems; absorption solar cooling systems; desiccant solar cooling systems; solar heat pump systems; solar hot water systems; special projects (such as the National Solar Data Network, hybrid solar thermal/photovoltaic applications, and heat transfer and water migration in soils); administrative/management support; and solar collector, storage, controls, analysis, and materials technology. (LEW)

  18. On the Relationship Between Solar Wind Speed, Geomagnetic Activity, and the Solar Cycle Using Annual Values

    Wilson, Robert M.; Hathaway, David H.

    2008-01-01

    The aa index can be decomposed into two separate components: the leading sporadic component due to solar activity as measured by sunspot number and the residual or recurrent component due to interplanetary disturbances, such as coronal holes. For the interval 1964-2006, a highly statistically important correlation (r = 0.749) is found between annual averages of the aa index and the solar wind speed (especially between the residual component of aa and the solar wind speed, r = 0.865). Because cyclic averages of aa (and the residual component) have trended upward during cycles 11-23, cyclic averages of solar wind speed are inferred to have also trended upward.

  19. Solar-collector manufacturing activity, July through December, 1981

    None

    1982-03-01

    Solar thermal collector and solar cell manufacturing activity is both summarized and tabulated. Data are compared for three survey periods (July through December, 1981; January through June, 1981; and July through December, 1980). Annual totals are also provided for the years 1979 through 1981. Data include total producer shipments, end use, market sector, imports and exports. (LEW)

  20. Helicity of Solar Active Regions from a Dynamo Model

    Piyali Chatterjee

    2006-06-01

    We calculate helicities of solar active regions based on the idea that poloidal flux lines get wrapped around a toroidal flux tube rising through the convection zone, thereby giving rise to the helicity. We use our solar dynamo model based on the Babcock–Leighton -effect to study how helicity varies with latitude and time.

  1. Solar Energy Education. Renewable energy activities for biology

    1982-01-01

    An instructional aid for teachers is presented that will allow biology students the opportunity to learn about renewable energy sources. Some of the school activities include using leaves as collectors of solar energy, solar energy stored in wood, and a fuel value test for green and dry woods. A study of organic wastes as a source of fuel is included. (BCS)

  2. Solar energy education. Renewable energy activities for general science

    1985-01-01

    Renewable energy topics are integrated with the study of general science. The literature is provided in the form of a teaching manual and includes such topics as passive solar homes, siting a home for solar energy, and wind power for the home. Other energy topics are explored through library research activities. (BCS)

  3. Recent perspectives in solar physics - Elemental composition, coronal structure and magnetic fields, solar activity

    Newkirk, G., Jr.

    1975-01-01

    Elemental abundances in the solar corona are studied. Abundances in the corona, solar wind and solar cosmic rays are compared to those in the photosphere. The variation in silicon and iron abundance in the solar wind as compared to helium is studied. The coronal small and large scale structure is investigated, emphasizing magnetic field activity and examining cosmic ray generation mechanisms. The corona is observed in the X-ray and EUV regions. The nature of coronal transients is discussed with emphasis on solar-wind modulation of galactic cosmic rays. A schematic plan view of the interplanetary magnetic field during sunspot minimum is given showing the presence of magnetic bubbles and their concentration in the region around 4-5 AU by a fast solar wind stream.

  4. The Magnetic Classification of Solar Active Regions 1992 - 2015

    Jaeggli, Sarah A.; Norton, Aimee A.

    2016-01-01

    The purpose of this letter is to address a blind-spot in our knowledge of solar active region statistics. To the best of our knowledge there are no published results showing the variation of the Mount Wilson magnetic classifications as a function of solar cycle based on modern observations. We show statistics for all active regions reported in the daily Solar Region Summary from 1992 January 1 to 2015 December 31. We find that the $\\alpha$ and $\\beta$ class active regions (including all sub-g...

  5. A Solar Cycle Dependence of Nonlinearity in Magnetospheric Activity

    Johnson, Jay R; Wing, Simon

    2005-03-08

    The nonlinear dependencies inherent to the historical K(sub)p data stream (1932-2003) are examined using mutual information and cumulant based cost as discriminating statistics. The discriminating statistics are compared with surrogate data streams that are constructed using the corrected amplitude adjustment Fourier transform (CAAFT) method and capture the linear properties of the original K(sub)p data. Differences are regularly seen in the discriminating statistics a few years prior to solar minima, while no differences are apparent at the time of solar maximum. These results suggest that the dynamics of the magnetosphere tend to be more linear at solar maximum than at solar minimum. The strong nonlinear dependencies tend to peak on a timescale around 40-50 hours and are statistically significant up to one week. Because the solar wind driver variables, VB(sub)s and dynamical pressure exhibit a much shorter decorrelation time for nonlinearities, the results seem to indicate that the nonlinearity is related to internal magnetospheric dynamics. Moreover, the timescales for the nonlinearity seem to be on the same order as that for storm/ring current relaxation. We suggest that the strong solar wind driving that occurs around solar maximum dominates the magnetospheric dynamics suppressing the internal magnetospheric nonlinearity. On the other hand, in the descending phase of the solar cycle just prior to solar minimum, when magnetospheric activity is weaker, the dynamics exhibit a significant nonlinear internal magnetospheric response that may be related to increased solar wind speed.

  6. Recent solar flare activity and its effect on in-orbit solar arrays

    This paper discusses how we are in the 22nd solar cycle, which began in September 1986 and appears to be as active as the 19th cycle, one of the most active ever observed. Solar flares during the active portion of this cycle can cause radio and communication disruptions; auroras at the poles; expanding of the earth's upper atmosphere, adding increased atmospheric drag on satellites; and degradation of electrical components on satellites---the result of the occasional major solar proton flare. Three major solar proton events (12 August, 29 September, and 19 October 1989) occurred thus far in the 22nd solar cycle. The in-orbit solar array performance of 11 geosynchronous spacecraft was analyzed to determine the effects from these events. The observed degradation was compared to predicted degradations using the flux energy spectra given by the GOES 7 detectors. The observed in-orbit performance degradation to the solar array varied from 2 to 5% for current at a given voltage, depending on the type of solar cells, cover glass thickness, and length of time in-orbit

  7. Preliminary design activities for solar heating and cooling systems

    1978-01-01

    Information on the development of solar heating and cooling systems is presented. The major emphasis is placed on program organization, system size definition, site identification, system approaches, heat pump and equipment design, collector procurement, and other preliminary design activities.

  8. Secular variations in the solar corona shape according to observations during a solar activity minimum epoch

    Tlatov, A. G.

    2008-01-01

    Analysis of the solar corona structure during the periods of minimum solar activity from 1867 till 2006 has been carried out. A new flattening index for the large coronal streamers has been proposed. It has been shown that the index has been smoothly changing during the last 140 years. The minimal value of the index occurred during activity cycles 17--19; this was the period when the solar corona most of all corresponded to the dipole configuration of the global magnetic field of the Sun. At ...

  9. Edge Adapted Wavelets, Solar Magnetic Activity, and Climate Change

    Johnson, Robert W

    2009-01-01

    The continuous wavelet transform is adapted to account for signal truncation through renormalization and by modifying the shape of the analyzing window. Comparison is made of the instant and integrated wavelet power with previous algorithms. The edge adapted and renormalized admissible wavelet transforms are used to estimate the level of solar magnetic activity from the sunspot record. The solar activity is compared to Oerlemans' temperature reconstruction and to the Central England Temperatu...

  10. Solar active envelope module with an adjustable transmittance/absorptance

    C. Villasante Villasante; I. del Hoyo; Pagola, I. (I.); Sanchez, M.; E. Aranzabe

    2015-01-01

    A solar active envelope module with a high flexibility degree is proposed in this paper. The transparent module controls the day-lighting of the room, improving the indoor environment, while absorbing the superfluous solar energy inside. That energy is used to increase the efficiency of heating, ventilation, and the air-conditioning (HVAC) system of the building. This is carried out through a fine control of the absorptance of the envelope module. The active envelope module consists of three ...

  11. Solar activity dependence of nightside aurora in winter conditions

    Zhou, Su; Luan, Xiaoli; Dou, Xiankang

    2016-02-01

    The dependence of the nightside (21:00-03:00 MLT; magnetic local time) auroral energy flux on solar activity was quantitatively studied for winter/dark and geomagnetically quiet conditions. Using data combined from Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics/Global Ultraviolet Imager and Defense Meteorological Satellite Program/Special Sensor Ultraviolet Spectrographic Imager observations, we separated the effects of geomagnetic activity from those of solar flux on the nightside auroral precipitation. The results showed that the nightside auroral power was reduced by ~42% in solar maximum (F10.7 = 200 sfu; solar flux unit 1 sfu = 10-22 W m-2 Hz-1) with respect to that under solar minimum (F10.7 = 70 sfu) for the Kp = 1 condition, and this change rate became less (~21%) for the Kp = 3 condition. In addition, the solar cycle dependence of nightside auroral power was similar with that from both the premidnight (21:00-23:00 MLT) and postmidnight (01:00-03:00 MLT) sectors. These results indicated that as the ionospheric ionization increases with the enhanced auroral and geomagnetic activities, the solar activity dependences of nightside auroral power become weaker, at least under geomagnetically quiet conditions.

  12. Solar activity and life. A review

    Recent claims advocate a downward revision of the solar oxygen abundance. This is a reflection of what may be called a 'solar crisis' whereby we mean that previous consensus in our understanding of our nearest star was unfounded. The implications for solar physics, and chemistry, are obvious and much research in the near future will give us a much clearer understanding of the Sun. We wish to review and update recent work concerning the frontier between Space Weather (SpW) and Astrobiology. We argue that the present robust programs of various space agencies reinforce our hope for a better understanding of the bases of Astrobiology. Eventually with a more realistic model of the Sun, more reliable discussions of all the factors influencing the origin of life on Earth will be possible. (author)

  13. Radio Imaging Observations of Solar Activity Cycle and Its Anomaly

    Shibasaki, K.

    2011-12-01

    The 24th solar activity cycle has started and relative sunspot numbers are increasing. However, their rate of increase is rather slow compared to previous cycles. Active region sizes are small, lifetime is short, and big (X-class) flares are rare so far. We study this anomalous situation using data from Nobeyama Radioheliograph (NoRH). Radio imaging observations have been done by NoRH since 1992. Nearly 20 years of daily radio images of the Sun at 17 GHz are used to synthesize a radio butterfly diagram. Due to stable operation of the instrument and a robust calibration method, uniform datasets are available covering the whole period of observation. The radio butterfly diagram shows bright features corresponding to active region belts and their migration toward low latitude as the solar cycle progresses. In the present solar activity cycle (24), increase of radio brightness is delayed and slow. There are also bright features around both poles (polar brightening). Their brightness show solar cycle dependence but peaks around solar minimum. Comparison between the last minimum and the previous one shows decrease of its brightness. This corresponds to weakening of polar magnetic field activity between them. In the northern pole, polar brightening is already weakened in 2011, which means it is close to solar maximum in the northern hemisphere. Southern pole does not show such feature yet. Slow rise of activity in active region belt, weakening of polar activity during the minimum, and large north-south asymmetry in polar activity imply that global solar activity and its synchronization are weakening.

  14. Latitude migration of solar activity at high latitudes

    2008-01-01

    Utilized here is the Carte Synoptique solar filament archive,namely the catalogue of solar filaments from March 1919 to December 1989,corresponding to solar rotation numbers 876 to 1823 to study Iatitudinal migration of solar activity at high Iatitudes.Except the well-known poleward migration of solar activity from middle Iatitudes to the poles,an equatorward migration is found from the solar poles toward middle Iatitudes(about 40°)within a normal cycle,which iS neglected before,and the time interval for the former migration(4.4 years)is about 2.2 years shorter than that for the latter(6.6 years),indicating that the change from one migration to the other takes place around the maximum time of a normal cycle.In the future,a dynamo model should represent the migration from the poles toward middle Iatitudes of the Sun,besides the migration in"butterfly diagrams"and the"rush to the poles".The traditional extended activity cycle is actually a part of the period of the successive migration from the poles toward the solar equator.

  15. Are cold winters in Europe associated with low solar activity?

    Lockwood, M; Harrison, R G; Woollings, T [Space Environment Physics Group, Department of Meteorology, University of Reading, Earley Gate, PO Box 243, Reading RG6 6BB (United Kingdom); Solanki, S K, E-mail: m.lockwood@reading.ac.uk [MPI fuer Sonnensystemforschung, Max-Planck-Strasse 2, 37191 Katlenburg-Lindau (Germany)

    2010-04-15

    Solar activity during the current sunspot minimum has fallen to levels unknown since the start of the 20th century. The Maunder minimum (about 1650-1700) was a prolonged episode of low solar activity which coincided with more severe winters in the United Kingdom and continental Europe. Motivated by recent relatively cold winters in the UK, we investigate the possible connection with solar activity. We identify regionally anomalous cold winters by detrending the Central England temperature (CET) record using reconstructions of the northern hemisphere mean temperature. We show that cold winter excursions from the hemispheric trend occur more commonly in the UK during low solar activity, consistent with the solar influence on the occurrence of persistent blocking events in the eastern Atlantic. We stress that this is a regional and seasonal effect relating to European winters and not a global effect. Average solar activity has declined rapidly since 1985 and cosmogenic isotopes suggest an 8% chance of a return to Maunder minimum conditions within the next 50 years (Lockwood 2010 Proc. R. Soc. A 466 303-29): the results presented here indicate that, despite hemispheric warming, the UK and Europe could experience more cold winters than during recent decades.

  16. Active solar heating and cooling information user study

    Belew, W.W.; Wood, B.L.; Marle, T.L.; Reinhardt, C.L.

    1981-01-01

    The results of a series of telephone interviews with groups of users of information on active solar heating and cooling (SHAC). An earlier study identified the information user groups in the solar community and the priority (to accelerate solar energy commercialization) of getting information to each group. In the current study only high-priority groups were examined. Results from 19 SHAC groups respondents are analyzed in this report: DOE-Funded Researchers, Non-DOE-Funded Researchers, Representatives of Manufacturers (4 groups), Distributors, Installers, Architects, Builders, Planners, Engineers (2 groups), Representatives of Utilities, Educators, Cooperative Extension Service County Agents, Building Owners/Managers, and Homeowners (2 groups). The data will be used as input to the determination of information products and services the Solar Energy Research Institute, the Solar Energy Information Data Bank Network, and the entire information outreach community should be preparing and disseminating.

  17. Cost Effective System Modeling of Active Micro- Module Solar Tracker

    Md. Faisal Shuvo

    2014-01-01

    Full Text Available The increasing interests in using renewable energies are coming from solar thermal energy and solar photovoltaic systems to the micro production of electricity. Usually we already have considered the solar tracking topology in large scale applications like power plants and satellite but most of small scale applications don’t have any solar tracker system, mainly because of its high cost and complex circuit design. From that aspect, this paper confab microcontroller based one dimensional active micro-module solar tracking system, in which inexpensive LDR is used to generate reference voltage to operate microcontroller for functioning the tracking system. This system provides a fast response of tracking system to the parameters like change of light intensity as well as temperature variations. This micro-module model of tracking system can be used for small scale applications like portable electronic devices and running vehicles.

  18. Breakup of loosely bound nuclei as indirect method in nuclear astrophysics. 8B, 9C, 23Al

    We discuss the use of one-nucleon breakup reactions of loosely bound nuclei at intermediate energies as an indirect method in nuclear astrophysics. These are peripheral processes, therefore from breakup reaction data we can extract asymptotic normalization coefficients (ANC) from which reaction rates of astrophysical interest can be precisely evaluated. In particular, the breakup of 8B and 9C is described in detail in terms of an extended Glauber model. The results of this new analysis lead to the astrophysical factor S17(0) = 18.7 ± 1.9 eVb for the key reaction for solar neutrino production 7Be(p,γ)8B. We discuss a proposed use of the breakup of proton drip line nucleus 23Al to obtain the stellar reaction rate for 22Mg(p,γ)23Al. (author)

  19. Solar activity monitoring and forecasting capabilities at Big Bear Solar Observatory

    P. T. Gallagher

    Full Text Available The availability of full-disk, high-resolution Ha images from Big Bear Solar Observatory (USA, Kanzelhöhe Solar Observatory (Austria, and Yunnan Astronomical Observatory (China allows for the continual monitoring of solar activity with unprecedented spatial and temporal resolution. Typically, this Global Ha Network (GHN provides almost uninterrupted Ha images with a cadence of 1 min and an image scale of 1'' per pixel. 

    Every hour, GHN images are transferred to the web-based BBSO Active Region Monitor (ARM; www.bbso.njit.edu/arm, which includes the most recent EUV, continuum, and magnetogram data from the Solar and Heliospheric Observatory, together with magnetograms from the Global Oscillation Network Group. ARM also includes a variety of active region properties from the National Oceanic and Atmospheric Administration’s Space Environment Center, such as up-to-date active region positions, GOES 5-min X-ray data, and flare identification. Stokes I, V, Q, and U images are available from the recently operational BBSO Digital Vector Magnetograph and the Vector Magnetograph at the Huairou Solar Observing Station of Beijing Observatory. Vector magnetograms provide complete information on the photospheric magnetic field, and allow for magnetic flux gradients, electric currents, and shear forces to be calculated: these measurements are extremely sensitive to conditions resulting in flaring activity. Furthermore, we have developed a Flare Prediction System which estimates the probability for each region to produce C-, M-, or X-class flares based on nearly eight years of NOAA data from cycle 22. This, in addition to BBSO’s daily solar activity reports, has proven a useful resource for activity forecasting.

    Key words. Solar physics, astronomy and astrophysics (flares and mass ejections; instruments and techniques

  20. Can origin of the 2400-year cycle of solar activity be caused by solar inertial motion?

    I. Charvátová

    2000-01-01

    A solar activity cycle of about 2400 years has until now been of uncertain origin. Recent results indicate it is caused by solar inertial motion. First we describe the 178.7-year basic cycle of solar motion. The longer cycle, over an 8000 year interval, is found to average 2402.2 years. This corresponds to the Jupiter/Heliocentre/Barycentre alignments (9.8855 × 243). Within each cycle an exceptional segment of 370 years has been found characterized by a looping pattern by a trefoil or quasitr...

  1. Solar activity forecast with a dynamo model

    Jiang, Jie; Chatterjee, Piyali; Choudhuri, Arnab Rai

    2007-01-01

    Although systematic measurements of the solar polar magnetic field exist only from mid 1970s, other proxies can be used to infer the polar field at earlier times. The observational data indicate a strong correlation between the polar field at a sunspot minimum and the strength of the next cycle, although the strength of the cycle is not correlated well with the polar field produced at its end. This suggests that the Babcock Leighton mechanism of poloidal field generation from decaying sunspot...

  2. Ionospheric disturbances under low solar activity conditions

    Burešová, Dalia; Laštovička, Jan; Hejda, Pavel; Bochníček, Josef

    2014-01-01

    Roč. 54, č. 2 (2014), s. 185-196. ISSN 0273-1177 R&D Projects: GA ČR(CZ) GAP209/11/1908 Institutional support: RVO:68378289 ; RVO:67985530 Keywords : ionosphere * solar minimum * magnetic storms * ionospheric variability Subject RIV: DG - Athmosphere Sciences, Meteorology; DG - Athmosphere Sciences, Meteorology (GFU-E) Impact factor: 1.358, year: 2014 http://www.sciencedirect.com/science/article/pii/S027311771400221X

  3. Danish participation in the IEA solar cell activities

    In the 12-month period 01.05.93 - 30.04.94 the Danish activities in the IEA 'Solar Cell Agreement' consisted in: participation in the Executive Committee (ExCo) and participation in Task 1 'Exchange and Dissemination of Information on PV Power Systems'. ExCo has meetings every half-year and is a coordinating organ for the Agreement. Work on the Task 1 is organized in 4 subtasks: (1) mapping of solar cell activities in the OECD countries and preparation of an IEA handbook on solar cell technology; (2) publishing of a semiannual newsletter about the agreement; (3) an 'executive conference' on solar cell technology and its uses with participation of the decision-makers in respective power industries; (4) information dissemination whenever required. Demonstration projects, like a photovoltaic roof-integrated system connected to the grid. have been implemented. Three larger solar cell projects, subsidized by the EU means, comprehend 'real time monitoring' by a solar system, WHO project 'Solar Energy Applications for Primary Health Care Clinics for Remote Rural Areas' (SAPHIR) and a grid-connected photovoltaic system in a suburb residential settlement. (EG)

  4. The Magnetic Classification of Solar Active Regions 1992-2015

    Jaeggli, S. A.; Norton, A. A.

    2016-03-01

    The purpose of this Letter is to address a blindspot in our knowledge of solar active region (AR) statistics. To the best of our knowledge, there are no published results showing the variation of the Mount Wilson magnetic classifications as a function of solar cycle based on modern observations. We show statistics for all ARs reported in the daily Solar Region Summary from 1992 January 1 to 2015 December 31. We find that the α and β class ARs (including all sub-groups, e.g., βγ, βδ) make up fractions of approximately 20% and 80% of the sample, respectively. This fraction is relatively constant during high levels of activity however, an increase in the α fraction to about 35% and and a decrease in the β fraction to about 65% can be seen near each solar minimum and are statistically significant at the 2σ level. Over 30% of all ARs observed during the years of solar maxima were appended with the classifications γ and/or δ, while these classifications account for only a fraction of a percent during the years near the solar minima. This variation in the AR types indicates that the formation of complex ARs may be due to the pileup of frequent emergence of magnetic flux during solar maximum, rather than the emergence of complex, monolithic flux structures.

  5. Investigation of relationships between parameters of solar nano-flares and solar activity

    Safari, Hossein; Javaherian, Mohsen; Kaki, Bardia

    2016-07-01

    Solar flares are one of the important coronal events which are originated in solar magnetic activity. They release lots of energy during the interstellar medium, right after the trigger. Flare prediction can play main role in avoiding eventual damages on the Earth. Here, to interpret solar large-scale events (e.g., flares), we investigate relationships between small-scale events (nano-flares) and large-scale events (e.g., flares). In our method, by using simulations of nano-flares based on Monte Carlo method, the intensity time series of nano-flares are simulated. Then, the solar full disk images taken at 171 angstrom recorded by SDO/AIA are employed. Some parts of the solar disk (quiet Sun (QS), coronal holes (CHs), and active regions (ARs)) are cropped and the time series of these regions are extracted. To compare the simulated intensity time series of nano-flares with the intensity time series of real data extracted from different parts of the Sun, the artificial neural networks is employed. Therefore, we are able to extract physical parameters of nano-flares like both kick and decay rate lifetime, and the power of their power-law distributions. The procedure of variations in the power value of power-law distributions within QS, CH is similar to AR. Thus, by observing the small part of the Sun, we can follow the procedure of solar activity.

  6. Fast growth associated with aberrant vasculature and hypoxia in fibroblast growth factor 8b (FGF8b over-expressing PC-3 prostate tumour xenografts

    Kinnunen Ilpo

    2010-10-01

    Full Text Available Abstract Background Prostate tumours are commonly poorly oxygenated which is associated with tumour progression and development of resistance to chemotherapeutic drugs and radiotherapy. Fibroblast growth factor 8b (FGF8b is a mitogenic and angiogenic factor, which is expressed at an increased level in human prostate tumours and is associated with a poor prognosis. We studied the effect of FGF8b on tumour oxygenation and growth parameters in xenografts in comparison with vascular endothelial growth factor (VEGF-expressing xenografts, representing another fast growing and angiogenic tumour model. Methods Subcutaneous tumours of PC-3 cells transfected with FGF8b, VEGF or empty (mock vectors were produced and studied for vascularity, cell proliferation, glucose metabolism and oxygenation. Tumours were evaluated by immunohistochemistry (IHC, flow cytometry, use of radiolabelled markers of energy metabolism ([18F]FDG and hypoxia ([18F]EF5, and intratumoral polarographic measurements of pO2. Results Both FGF8b and VEGF tumours grew rapidly in nude mice and showed highly vascularised morphology. Perfusion studies, pO2 measurements, [18F]EF5 and [18F]FDG uptake as well as IHC staining for glucose transport protein (GLUT1 and hypoxia inducible factor (HIF 1 showed that VEGF xenografts were well-perfused and oxygenised, as expected, whereas FGF8b tumours were as hypoxic as mock tumours. These results suggest that FGF8b-induced tumour capillaries are defective. Nevertheless, the growth rate of hypoxic FGF8b tumours was highly increased, as that of well-oxygenised VEGF tumours, when compared with hypoxic mock tumour controls. Conclusion FGF8b is able to induce fast growth in strongly hypoxic tumour microenvironment whereas VEGF-stimulated growth advantage is associated with improved perfusion and oxygenation of prostate tumour xenografts.

  7. Fast growth associated with aberrant vasculature and hypoxia in fibroblast growth factor 8b (FGF8b) over-expressing PC-3 prostate tumour xenografts

    Prostate tumours are commonly poorly oxygenated which is associated with tumour progression and development of resistance to chemotherapeutic drugs and radiotherapy. Fibroblast growth factor 8b (FGF8b) is a mitogenic and angiogenic factor, which is expressed at an increased level in human prostate tumours and is associated with a poor prognosis. We studied the effect of FGF8b on tumour oxygenation and growth parameters in xenografts in comparison with vascular endothelial growth factor (VEGF)-expressing xenografts, representing another fast growing and angiogenic tumour model. Subcutaneous tumours of PC-3 cells transfected with FGF8b, VEGF or empty (mock) vectors were produced and studied for vascularity, cell proliferation, glucose metabolism and oxygenation. Tumours were evaluated by immunohistochemistry (IHC), flow cytometry, use of radiolabelled markers of energy metabolism ([18F]FDG) and hypoxia ([18F]EF5), and intratumoral polarographic measurements of pO2. Both FGF8b and VEGF tumours grew rapidly in nude mice and showed highly vascularised morphology. Perfusion studies, pO2 measurements, [18F]EF5 and [18F]FDG uptake as well as IHC staining for glucose transport protein (GLUT1) and hypoxia inducible factor (HIF) 1 showed that VEGF xenografts were well-perfused and oxygenised, as expected, whereas FGF8b tumours were as hypoxic as mock tumours. These results suggest that FGF8b-induced tumour capillaries are defective. Nevertheless, the growth rate of hypoxic FGF8b tumours was highly increased, as that of well-oxygenised VEGF tumours, when compared with hypoxic mock tumour controls. FGF8b is able to induce fast growth in strongly hypoxic tumour microenvironment whereas VEGF-stimulated growth advantage is associated with improved perfusion and oxygenation of prostate tumour xenografts

  8. Solar-Type Activity in Main-Sequence Stars

    Gershberg, Roald E

    2005-01-01

    Solar-type activity over the whole range of the electromagnetic spectrum is a phenomenon inherent in the majority of low- and moderate-mass main sequence stars. In this monograph observational results are summarized in a systematic and comprehensive fashion. The analysis of the various manifestations of such stellar activity leads to the identification of these phenomena with macroscopic non-linear processes in a magnetized plasma. Comparative study of flare stars and the Sun has become increasingly fruitful and is presently an active field of research involving stellar and solar physicists, experts in plasma physics and high-energy astrophysicists. This book will provide them with both an introduction and overview of observational results from the first optical photometry and spectroscopy, from the satellite telescopes International Ultraviolet Explorer to Hubble Space Telescope, XMM-Newton and Chandra, as well as with the present physical interpretation of solar-type activity in main sequence stars. Gershbe...

  9. The Magnetic Classification of Solar Active Regions 1992 - 2015

    Jaeggli, Sarah A

    2016-01-01

    The purpose of this letter is to address a blind-spot in our knowledge of solar active region statistics. To the best of our knowledge there are no published results showing the variation of the Mount Wilson magnetic classifications as a function of solar cycle based on modern observations. We show statistics for all active regions reported in the daily Solar Region Summary from 1992 January 1 to 2015 December 31. We find that the $\\alpha$ and $\\beta$ class active regions (including all sub-groups e.g. $\\beta\\gamma$, $\\beta\\delta$) make up fractions of approximately 20% and 80% of the sample respectively. This fraction is relatively constant during high levels of activity, however, an increase in the $\\alpha$ fraction to about 35% and and a decrease in the $\\beta$ fraction to about 65% can be seen near each solar minimum and is statistically significant at the 2-$\\sigma$ level. Over 30% of all active regions observed during the years of solar maxima were appended with the classifications $\\gamma$ and/or $\\del...

  10. The risk characteristics of solar and geomagnetic activity

    Podolská, Kateřina

    Göttingen: European Geosciences Union, 2016. EGU2016-10230. ISSN 1607-7962. [EGU General Assembly 2016. 17.04.2016-22.04.2016, Vienna] Institutional support: RVO:68378289 Keywords : solar activity * geomagnetic activity * mortality Subject RIV: DG - Athmosphere Sciences, Meteorology http://meetingorganizer.copernicus.org/EGU2016/EGU2016-10230.pdf

  11. Experimental evaluation of an active solar thermoelectric radiant wall system

    Highlights: • A novel active solar thermoelectric radiant wall are proposed and tested. • The novel wall can control thermal flux of building envelope by using solar energy. • The novel wall can eliminate building envelop thermal loads and provide cooling capacity for space cooling. • Typical application issues including connection strategies, coupling with PV system etc. are discussed. - Abstract: Active solar thermoelectric radiant wall (ASTRW) system is a new solar wall technology which integrates thermoelectric radiant cooling and photovoltaic (PV) technologies. In ASTRW system, a PV system transfers solar energy directly into electrical energy to power thermoelectric cooling modes. Both the thermoelectric cooling modes and PV system are integrated into one enclosure surface as radiant panel for space cooling and heating. Hence, ASTRW system presents fundamental shift from minimizing building envelope energy losses by optimizing the insulation thickness to a new regime where active solar envelop is designed to eliminate thermal loads and increase the building’s solar gains while providing occupant comfort in all seasons. This article presents an experimental study of an ASTRW system with a dimension of 1580 × 810 mm. Experimental results showed that the inner surface temperature of the ASTRW is 3–8 °C lower than the indoor temperature of the test room, which indicated that the ASTRW system has the ability to control thermal flux of building envelope by using solar energy and reduce the air conditioning system requirements. Based on the optimal operating current of TE modules and the analysis based upon PV modeling theories, the number and type of the electrical connections for the TE modules in ASTRW system are discussed in order to get an excellent performance in the operation of the ASTRW system

  12. North-south asymmetry of different solar activity features during solar cycle 23

    Bankoti, Neeraj Singh; Joshi, Navin Chandra; Pande, Seema; Pande, Bimal; Pandey, Kavita

    2010-08-01

    A study on north-south (N-S) asymmetry of different solar activity features (DSAF) such as solar proton events, solar active prominences [total, low (⩽40°) and high (⩾50°) latitudes], H α flare indices, soft X-ray flares, monthly mean sunspot areas and monthly mean sunspot numbers carried out from May 1996 to October 2008. Study shows a southern dominance of DSAF during this period. During the rising phase of the cycle 23 the number of DSAF approximately equals on both, the northern and the southern hemispheres. But these activities tend to shift from northern to southern hemisphere during the period 1998-1999. The statistical significance of the asymmetry time series using a χ2-test of goodness of fit indicates that in most of the cases the asymmetry is highly significant, meaning thereby that the asymmetry is a real feature in the N-S distribution of DSAF.

  13. Adsorption of Procion Red MX 8B using spent tea leaves as adsorbent

    Heraldy, Eddy; Osa, Riesta Ramdhaniyati; Suryanti, Venty

    2016-02-01

    The adsorption of Procion Red MX 8B using spent tea leaves (STL) as adsorbent, has been studied by batch adsorption technique. The adsorbent was activated by NaOH 4% for 24 hours for delignification process. The adsorbent was characterized using FTIR to indetify the functional groups of cellulose was shown by uptake -OH, C-H and C-O. The optimum conditions of adsorption experiments were achieved when pH was set as 6 with contact time of 75 minutes and capacity of adsorption was 3.28 mg/g. The equilibrium data were fitted to Langmuir and Isotherm Freundlichs. The kinetic models, pseudo first order and pseudo second order were employed to describe the adsorption mechanism. The experimental results showed that the pseudo second order equation was the best model that described the adsorption behavior with the coefficient of correlation (R2) was equal higher than 0.99 The results suggested that STL had high potential to be used as effective adsorbent for Procion Red MX 8B removal.

  14. Solar Activity Studies using Microwave Imaging Observations

    Gopalswamy, Nat

    2016-01-01

    We report on the status of solar cycle 24 based on polar prominence eruptions (PEs) and microwave brightness enhancement (MBE) information obtained by the Nobeyama radioheliograph. The north polar region of the Sun had near-zero field strength for more than three years (2012 to 2015) and ended only in September 2015 as indicated by the presence of polar PEs and the lack of MBE. The zero-polar-field condition in the south started only around 2013, but it ended by June 2014. Thus the asymmetry in the times of polarity reversal switched between cycle 23 and 24. The polar MBE is a good proxy for the polar magnetic field strength as indicated by the high degree of correlation between the two. The cross-correlation between the high- and low-latitude MBEs is significant for a lag of ~5.5 to 7.3 years, suggesting that the polar field of one cycle indicates the sunspot number of the next cycle in agreement with the Babcock-Leighton mechanism of solar cycles. The extended period of near-zero field in the north-polar re...

  15. IS THE CURRENT LACK OF SOLAR ACTIVITY ONLY SKIN DEEP?

    The Sun is a variable star whose magnetic activity and total irradiance vary on a timescale of approximately 11 years. The current activity minimum has attracted considerable interest because of its unusual duration and depth. This raises the question: what might be happening beneath the surface where the magnetic activity ultimately originates? The surface activity can be linked to the conditions in the solar interior by the observation and analysis of the frequencies of the Sun's natural seismic modes of oscillation-the p modes. These seismic frequencies respond to changes in activity and are probes of conditions within the Sun. The Birmingham Solar-Oscillations Network (BiSON) has made measurements of p-mode frequencies over the last three solar activity cycles, and so is in a unique position to explore the current unusual and extended solar minimum. We show that the BiSON data reveal significant variations of the p-mode frequencies during the current minimum. This is in marked contrast to the surface activity observations, which show little variation over the same period. The level of the minimum is significantly deeper in the p-mode frequencies than in the surface observations. We observe a quasi-biennial signal in the p-mode frequencies, which has not previously been observed at mid- and low-activity levels. The stark differences in the behavior of the frequencies and the surface activity measures point to activity-related processes occurring in the solar interior, which are yet to reach the surface, where they may be attenuated.

  16. Initiation of non-tropical thunderstorms by solar activity

    Correlative evidence accumulating since 1926 suggests that there must be some physical coupling mechanism between solar activity and thunderstorm occurrence in middle to high latitudes. Such a link may be provided by alteration of atmospheric electric parameters through the influence of cosmic ray decreases and/or high-energy solar protons associated with active solar events. Galactic cosmic ray decreases tend to enhance the electric field at low heights. The protons produce excess ionization near and above 20 km, greatly increasing the atmospheric conductivity and possibly lowering the height of the electrosphere. Consequent effects near the solar proton cut-off latitude also lead to an enhancement of the atmospheric electric field near the surface. If appropriate meteorological conditions (warm moist air with updrafts) exist or develop during a solar event, the atmospheric electric field enhancement may be sufficient to trigger thunderstorm development. The suggested mechanism appears plausible enough to warrant a co-ordinated experimental effort involving satellite balloon and ground-based measurements of the possible forcing functions (solar protons and cosmic rays) and the responding atmospheric electrical and ionic species' characteristics. (author)

  17. Reconstructed Total Solar Irradiance as a precursor for long-term solar activity predictions: a nonlinear dynamics approach

    Sello, S

    2012-01-01

    Total solar irradiance variations, about 0.1% between solar activity maximum and minimum, are available from accurate satellite measurements since 1978 and thus do not provide useful information on longer-term secular trends. Recently, Krivova et al., 2007 reconstructed, using suitable models, the total solar irradiance from the end of the Maunder minimum to the present, based on variations of the surface distribution of the solar magnetic field. The latter is calculated from the long historical record of the sunspot numbers using a simple but consistent physical model. There are many classes of proposed prediction methods for solar cycles behavior, based on different direct solar activity indices or on various valuable proxies. In particular, the precursor based methods, utilize a given proxy index to predict the future evolution of solar activity. Long-term time series of sunspot numbers, allow us to reliably predict the behavior of the next solar cycle, few years in advance. In previous papers we predicted...

  18. Calibration Of Sno For The Detection Of (8)b Neutrinos

    Ford, R J

    1999-01-01

    The Sudbury Neutrino Observatory (SNO) is a second generation water Čerenkov detector using 1000 tonnes of heavy water to study neutrino astrophysics. Using deuterium neutrino reactions, SNO will measure the flux and energy spectrum of solar electron neutrinos, and will measure the flavour-blind flux of neutrinos. A nitrogen/multi-dye laser diffuser ball has been designed and installed in SNO for calibration of the electronics, photomultiplier tubes (PMTs) and optical parameters. The laser provides pulsed radiation at 337.1 nm with a 600 psec width and pulse rate up to 50 Hz. The laser can be used directly or as a pump for one of four dye laser resonators, which provides five wavelength selections from 337–500 nm. The light is delivered to a pseudo-isotropic diffuser ball (the laserball) by a 100 μm UV-VIS fibre bundle with less than 1 nsec dispersion at 337 nm. The laserball can be deployed throughout the detector with the rope manipulator system. The laserball output is adjustabl...

  19. Multi-parametric Effect of Solar Activity on Cosmic Rays

    V. K. Mishra; Meera Gupta; B. N. Mishra; S. K. Nigam; A. P. Mishra

    2008-03-01

    The long-term modulation of cosmic ray intensity (CRI) by different solar activity (SA) parameters and an inverse correlation between individual SA parameter and CRI is well known. Earlier, it has been suggested that the concept of multi-parametric modulation of CRI may play an important role in the study of long-term modulation of CRI. In the present study, we have tried to investigate the combined effect of a set of two SA parameters in the long-term modulation of CRI. For this purpose, we have used a new statistical technique called “Running multiple correlation method”, based on the “Running cross correlation method”. The running multiple correlation functions among different sets of two SA parameters (e.g., sunspot numbers and solar flux, sunspot numbers and coronal index, sunspot numbers and grouped solar flares, etc.) and CRI have been correlated separately. It is found that the strength of multiple correlation (among two SA parameters and CRI) and cross correlation (between individual SA parameter and CRI) is almost similar throughout the period of investigation (1955–2005). It is also found that the multiple correlations among various SA parameters and CRI is stronger during ascending and descending phases of the solar cycles and it becomes weaker during maxima and minima of the solar cycles, which is in accordance with the linear relationship between SA parameters and CRI. The values of multiple correlation functions among different sets of SA parameters and CRI fall well within the 95% confidence interval. In the view of odd–even hypothesis of solar cycles, the strange behaviour of present cycle 23 (odd cycle), as this is characterized by many peculiarities with double peaks and many quiet periods (Gnevyshev gaps) interrupted the solar activity (for example April 2001, October–November 2003 and January 2005), leads us to speculate that the solar cycle 24 (even cycle) might be of exceptional nature.

  20. Is the current lack of solar activity only skin deep?

    Broomhall, A -M; Elsworth, Y; Fletcher, S T; New, R; 10.1088/0004-637X/700/2/L162

    2009-01-01

    The Sun is a variable star whose magnetic activity and total irradiance vary on a timescale of approximately 11 years. The current activity minimum has attracted considerable interest because of its unusual duration and depth. This raises the question: what might be happening beneath the surface where the magnetic activity ultimately originates? The surface activity can be linked to the conditions in the solar interior by the observation and analysis of the frequencies of the Sun's natural seismic modes of oscillation - the p modes. These seismic frequencies respond to changes in activity and are probes of conditions within the Sun. The Birmingham Solar-Oscillations Network (BiSON) has made measurements of p-mode frequencies over the last three solar activity cycles, and so is in a unique position to explore the current unusual and extended solar minimum. We show that the BiSON data reveal significant variations of the p-mode frequencies during the current minimum. This is in marked contrast to the surface ac...

  1. Edge Adapted Wavelets, Solar Magnetic Activity, and Climate Change

    Johnson, Robert W

    2009-01-01

    The continuous wavelet transform is adapted to account for signal truncation through renormalization and by modifying the shape of the analyzing window. Comparison is made of the instant and integrated wavelet power with previous algorithms. The edge adapted and renormalized admissible wavelet transforms are used to estimate the level of solar magnetic activity from the sunspot record. The solar activity is compared to Oerlemans' temperature reconstruction and to the Central England Temperature record. A correlation is seen for years between 1610 and 1990, followed by a strong deviation as the recently observed temperature increases.

  2. Measurement of the $^{7}$Be$(p,\\gamma)^{8}$B Cross-Section with an Implanted Target

    2002-01-01

    % IS366\\\\ \\\\ The $^7$Be(p,$\\gamma)^8$B capture reaction is of major importance to the physics of the sun and the issues of the ``solar neutrino puzzle'' and neutrino masses. We report here on a new determination of the absolute cross section of this reaction, using a novel method which overcomes some of the major experimental uncertainties of previous measurements. We utilize an implanted $^7$Be target and a uniformly scanned particle beam larger than the target spot, eliminating issues of target homogeneity and backscattering loss of $^8$B reaction products. The target was produced using a beam of 1.8 10$^{10}$/s $^7$Be nuclei extracted at ISOLDE(CERN) from a graphite target bombarded by 1 GeV protons in a two-step resonant laser ionization source. The $^7$Be nuclei were directly implanted into a copper substrate to obtain a target of 2 mm diameter with a total of 3.10$^{15}$ atoms. The measurement of the $^8$B production cross section was carried out at the Van de Graaff laboratory of the Weizmann Institute...

  3. The Solar System Ballet: A Kinesthetic Spatial Astronomy Activity

    Heyer, Inge; Slater, T. F.; Slater, S. J.; Astronomy, Center; Education ResearchCAPER, Physics

    2011-05-01

    The Solar System Ballet was developed in order for students of all ages to learn about the planets, their motions, their distances, and their individual characteristics. To teach people about the structure of our Solar System can be revealing and rewarding, for students and teachers. Little ones (and some bigger ones, too) often cannot yet grasp theoretical and spatial ideas purely with their minds. Showing a video is better, but being able to learn with their bodies, essentially being what they learn about, will help them understand and remember difficult concepts much more easily. There are three segments to this activity, which can be done together or separately, depending on time limits and age of the students. Part one involves a short introductory discussion about what students know about the planets. Then students will act out the orbital motions of the planets (and also moons for the older ones) while holding a physical model. During the second phase we look at the structure of the Solar System as well as the relative distances of the planets from the Sun, first by sketching it on paper, then by recreating a scaled version in the class room. Again the students act out the parts of the Solar System bodies with their models. The third segment concentrates on recreating historical measurements of Earth-Moon-Sun system. The Solar System Ballet activity is suitable for grades K-12+ as well as general public informal learning activities.

  4. DASL-Data and Activities for Solar Learning

    Jones, Harrison P.; Henney, Carl; Hill, Frank; Gearen, Michael; Pompca, Stephen; Stagg, Travis; Stefaniak, Linda; Walker, Connie

    2004-01-01

    DASL-Data and Activities for Solar Learning Data and Activities for Solar Learning (DASL) provides a classroom learning environment based on a twenty-five year record of solar magnetograms from the National Solar Observatory (NSO) at Kitt Peak, AZ. The data, together with image processing software for Macs or PCs, can be used to learn basic facts about the Sun and astronomy at the middle school level. At the high school level, students can study properties of the Sun's magnetic cycle with classroom exercises emphasizing data and error analysis and can participate in a new scientific study, Research in Active Solar Longitudes (RASL), in collaboration with classrooms throughout the country and scientists at NSO and NASA. We present a half-day course to train teachers in the scientific content of the project and its classroom use. We will provide a compact disc with the data and software and will demonstrate software installation and use, classroom exercises, and participation in RASL with computer projection.

  5. Phosphodiesterase 8B gene polymorphism in women with recurrent miscarriage: A retrospective case control study

    Granfors Michaela; Karypidis Helena; Hosseini Frida; Skjöldebrand-Sparre Lottie; Stavreus-Evers Anneli; Bremme Katarina; Landgren Britth-Marie; Sundström-Poromaa Inger; Wikström Anna-Karin; Åkerud Helena

    2012-01-01

    Abstract Background Recurrent miscarriage affects approximately 1% of all couples. There is a known relation between hypothyroidism and recurrent miscarriage. Phosphodiesterase 8B (PDE8B) is a regulator of cyclic adenosine monophosphate (cAMP) with important influence on human thyroid metabolism. Single nucleotide polymorphism (SNP) rs 4704397 in the PDE8B gene has been shown to be associated with variations in serum Thyroid Stimulating Hormone (TSH) and thyroxine (T4) levels. The aim of this...

  6. Rotation of the Earth, solar activity and cosmic ray intensity

    Barlyaeva, T.; Bard, E. [Aix-Marseille Univ., CNRS, IRD, Aix-en-Provence (France). CEREGE, College de France; Abarca-del-Rio, R. [Universidad de Concepcion (UDEC) (Chile). Dept. de Geofisica (DGEO)

    2014-10-01

    We analyse phase lags between the 11-year variations of three records: the semi-annual oscillation of the length of day (LOD), the solar activity (SA) and the cosmic ray intensity (CRI). The analysis was done for solar cycles 20-23. Observed relationships between LOD, CRI and SA are discussed separately for even and odd solar cycles. Phase lags were calculated using different methods (comparison of maximal points of cycles, maximal correlation coefficient, line of synchronization of cross-recurrence plots). We have found different phase lags between SA and CRI for even and odd solar cycles, confirming previous studies. The evolution of phase lags between SA and LOD as well as between CRI and LOD shows a positive trend with additional variations of phase lag values. For solar cycle 20, phase lags between SA and CRI, between SA and LOD, and between CRI and LOD were found to be negative. Overall, our study suggests that, if anything, the length of day could be influenced by solar irradiance rather than by cosmic rays.

  7. Rotation of the Earth, solar activity and cosmic ray intensity

    We analyse phase lags between the 11-year variations of three records: the semi-annual oscillation of the length of day (LOD), the solar activity (SA) and the cosmic ray intensity (CRI). The analysis was done for solar cycles 20-23. Observed relationships between LOD, CRI and SA are discussed separately for even and odd solar cycles. Phase lags were calculated using different methods (comparison of maximal points of cycles, maximal correlation coefficient, line of synchronization of cross-recurrence plots). We have found different phase lags between SA and CRI for even and odd solar cycles, confirming previous studies. The evolution of phase lags between SA and LOD as well as between CRI and LOD shows a positive trend with additional variations of phase lag values. For solar cycle 20, phase lags between SA and CRI, between SA and LOD, and between CRI and LOD were found to be negative. Overall, our study suggests that, if anything, the length of day could be influenced by solar irradiance rather than by cosmic rays.

  8. Solar Spectral Irradiance, Solar Activity, and the Near-Ultra-Violet

    Fontenla, J. M.; Stancil, P. C.; Landi, E.

    2015-08-01

    The previous calculations of the Solar Spectral Irradiance (SSI) by the Solar Radiation Physical Modeling, version 2 system, are updated in this work by including new molecular photodissociation cross-sections of important species, and many more levels and lines in its treatment of non-LTE radiative transfer. The current calculations including the new molecular photodissociation opacities produce a reduced over-ionizaton of heavy elements in the lower chromosphere and solve the problems with prior studies of the UV SSI in the wavelength range 160-400 nm and now reproduce the available observations with much greater accuracy. Calculations and observations of the near-UV at 0.1 nm resolution and higher are compared. The current set of physical models includes four quiet-Sun and five active-region components, from which radiance is computed for ten observing angles. These radiances are combined with images of the solar disk to obtain the SSI and Total Solar Irradiance and their variations. The computed SSI is compared with measurements from space at several nm resolution and agreement is found within the accuracy level of these measurements. An important result is that the near-UV SSI increase with solar activity is significant for the photodissociation of ozone in the terrestrial atmosphere because a number of highly variable upper chromospheric lines overlap the ozone Hartley band.

  9. Solar activity forecast with a dynamo model

    Jiang, Jie; Choudhuri, Arnab Rai

    2007-01-01

    Although systematic measurements of the solar polar magnetic field exist only from mid 1970s, other proxies can be used to infer the polar field at earlier times. The observational data indicate a strong correlation between the polar field at a sunspot minimum and the strength of the next cycle, although the strength of the cycle is not correlated well with the polar field produced at its end. This suggests that the Babcock Leighton mechanism of poloidal field generation from decaying sunspots involves randomness, whereas the other aspects of the dynamo process must be reasonably ordered and deterministic. Only if the magnetic diffusivity within the convection zone is assumed to be high, we can explain the correlation between the polar field at a minimum and the next cycle. We give several independent arguments that the diffusivity must be of this order. In a dynamo model with diffusivity like this, the poloidal field generated at the mid latitudes is advected toward the poles by the meridional circulation an...

  10. Solar activity and its evolution across the corona: recent advances

    Rodriguez Luciano

    2013-04-01

    Full Text Available Solar magnetism is responsible for the several active phenomena that occur in the solar atmosphere. The consequences of these phenomena on the solar-terrestrial environment and on Space Weather are nowadays clearly recognized, even if not yet fully understood. In order to shed light on the mechanisms that are at the basis of the Space Weather, it is necessary to investigate the sequence of phenomena starting in the solar atmosphere and developing across the outer layers of the Sun and along the path from the Sun to the Earth. This goal can be reached by a combined multi-disciplinary, multi-instrument, multi-wavelength study of these phenomena, starting with the very first manifestation of solar active region formation and evolution, followed by explosive phenomena (i.e., flares, erupting prominences, coronal mass ejections, and ending with the interaction of plasma magnetized clouds expelled from the Sun with the interplanetary magnetic field and medium. This wide field of research constitutes one of the main aims of COST Action ES0803: Developing Space Weather products and services in Europe. In particular, one of the tasks of this COST Action was to investigate the Progress in Scientific Understanding of Space Weather. In this paper we review the state of the art of our comprehension of some phenomena that, in the scenario outlined above, might have a role on Space Weather, focusing on the researches, thematic reviews, and main results obtained during the COST Action ES0803.

  11. Reconstructed Total Solar Irradiance as a precursor for long-term solar activity predictions: a nonlinear dynamics approach

    Sello, S.

    2012-01-01

    Total solar irradiance variations, about 0.1% between solar activity maximum and minimum, are available from accurate satellite measurements since 1978 and thus do not provide useful information on longer-term secular trends. Recently, Krivova et al., 2007 reconstructed, using suitable models, the total solar irradiance from the end of the Maunder minimum to the present, based on variations of the surface distribution of the solar magnetic field. The latter is calculated from the long histori...

  12. Screening a phage display library for a novel FGF8b-binding peptide with anti-tumor effect on prostate cancer

    Wang, Wenhui; Chen, Xilei; Li, Tao; Li, Yanmei; Wang, Ruixue; He, Dan; Luo, Wu [Institute of Tissue Transplantation and Immunology, Jinan University, Guangzhou 510632 (China); Li, Xiaokun [Institute of Tissue Transplantation and Immunology, Jinan University, Guangzhou 510632 (China); School of Pharmaceutical Science, Wenzhou Medical College, Wenzhou 325035 (China); Wu, Xiaoping, E-mail: twxp@jnu.edu.cn [Institute of Tissue Transplantation and Immunology, Jinan University, Guangzhou 510632 (China); School of Pharmaceutical Science, Wenzhou Medical College, Wenzhou 325035 (China)

    2013-05-01

    Fibroblast growth factor 8b (FGF8b) is the major isoform of FGF8 expressed in prostate cancer and it correlates with the stage and grade of the disease. FGF8b has been considered as a potential target for prostate cancer therapy. Here we isolated 12 specific FGF8b-binding phage clones by screening a phage display heptapeptide library with FGF8b. The peptide (HSQAAVP, named as P12) corresponding to one of these clones showed high homology to the immunoglobulin-like (Ig-like) domain II(D2) of high-affinity FGF8b receptor (FGFR3c), contained 3 identical amino acids (AVP) to the authentic FGFR3 D2 sequence aa 163–169 (LLAVPAA) directly participating in ligand binding, carried the same charges as its corresponding motif (aa163–169) in FGFR3c, suggesting that P12 may have a greater potential to interrupt FGF8b binding to its receptors than other identified heptapeptides do. Functional analysis indicated that synthetic P12 peptides mediate significant inhibition of FGF8b-induced cell proliferation, arrest cell cycle at the G0/G1 phase via suppression of Cyclin D1 and PCNA, and blockade of the activations of Erk1/2 and Akt cascades in both prostate cancer cells and vascular endothelial cells. The results demonstrated that the P12 peptide acting as an FGF8b antagonist may have therapeutic potential in prostate cancer. - Highlights: ► A novel FGF8b-binding peptide P12 was isolated from a phage display library. ► The mechanisms for P12 peptide inhibiting cell proliferation were proposed. ► P12 caused cell cycle arrest at G0/G1 phase via suppression of Cyclin D1 and PCNA. ► P12 suppressed FGF8b-induced activations of Akt and MAP kinases. ► P12 acting as an FGF8b antagonist may have therapeutic potential in prostate cancer.

  13. Screening a phage display library for a novel FGF8b-binding peptide with anti-tumor effect on prostate cancer

    Fibroblast growth factor 8b (FGF8b) is the major isoform of FGF8 expressed in prostate cancer and it correlates with the stage and grade of the disease. FGF8b has been considered as a potential target for prostate cancer therapy. Here we isolated 12 specific FGF8b-binding phage clones by screening a phage display heptapeptide library with FGF8b. The peptide (HSQAAVP, named as P12) corresponding to one of these clones showed high homology to the immunoglobulin-like (Ig-like) domain II(D2) of high-affinity FGF8b receptor (FGFR3c), contained 3 identical amino acids (AVP) to the authentic FGFR3 D2 sequence aa 163–169 (LLAVPAA) directly participating in ligand binding, carried the same charges as its corresponding motif (aa163–169) in FGFR3c, suggesting that P12 may have a greater potential to interrupt FGF8b binding to its receptors than other identified heptapeptides do. Functional analysis indicated that synthetic P12 peptides mediate significant inhibition of FGF8b-induced cell proliferation, arrest cell cycle at the G0/G1 phase via suppression of Cyclin D1 and PCNA, and blockade of the activations of Erk1/2 and Akt cascades in both prostate cancer cells and vascular endothelial cells. The results demonstrated that the P12 peptide acting as an FGF8b antagonist may have therapeutic potential in prostate cancer. - Highlights: ► A novel FGF8b-binding peptide P12 was isolated from a phage display library. ► The mechanisms for P12 peptide inhibiting cell proliferation were proposed. ► P12 caused cell cycle arrest at G0/G1 phase via suppression of Cyclin D1 and PCNA. ► P12 suppressed FGF8b-induced activations of Akt and MAP kinases. ► P12 acting as an FGF8b antagonist may have therapeutic potential in prostate cancer

  14. Study of Distribution and Asymmetry of Solar Active Prominences During Solar Cycle 23

    Joshi, Navin Chandra; Bankoti, Neeraj Singh; Pande, Seema; Pande, Bimal; Pandey, Kavita

    2009-01-01

    In this paper we present the results of a study of the spatial distribution and asymmetry of solar active prominences (SAP) for the period 1996-2007 (solar cycle 23). For more meaningful statistical analysis we have analysed the distribution and asymmetry of SAP in two subdivisions viz. Group1 (ADF, APR, DSF, CRN, CAP) and Group2 (AFS, ASR, BSD, BSL, DSD, SPY, LPS). The north-south (N-S) latitudinal distribution shows that the SAP events are most prolific in the 21-30degree slice in the north...

  15. Foothills Parkway Section 8B Final Environmental Report, Volume 2, Appendices A-C

    Blasing, T.J.; Cada, G.F.; Carer, M.; Chin, S.M.; Dickerman, J.A.; Etnier, D.A.; Gibson, R.; Harvey, M.; Hatcher, B.; Lietzske, D.; Mann, L.K.; Mulholland, P.J.; Petrich, C.H.; Pounds, L.; Ranney, J.; Reed, R.M.; Ryan, P.F.; Schweitzer, M.; Smith, D.; Thomason, P.; Wade, M.C.

    1999-07-01

    In 1994, Oak Ridge National Laboratory (ORNL) was tasked by the National Park Service (NPS) to prepare an Environmental Report (ER) for Section 8B of the Foothills Parkway in the Great Smoky Mountains National Park (GSMNP). Section 8B represents 27.7 km (14.2 miles) of a total of 115 km (72 miles) of the planned Foothills Parkway and would connect the Cosby community on the east to the incorporated town of Pittman Center to the west. The major deliverables for the project are listed. From August 1995 through October 1996, NW, GSMNP, and ORNL staff interacted with Federal Highway Administration staff to develop a conceptual design plan for Section 8B with the intent of protecting critical resources identified during the ER process to the extent possible. In addition, ORNL arranged for bioengineering experts to discuss techniques that might be employed on Section 8B with NPS, GSMNP, and ORNL staff during September 1996. For the purposes of this EN there are two basic alternatives under consideration: (1) a build alternative and (2) a no-build alternative. Within the build alternative are a number of options including constructing Section 8B with no interchanges, constricting Section 8B with an interchange at SR 416 or U.S. 321, constructing Section 8B with a spur road on Webb Mountain, and considering operation of Section 8B both before and after the operation of Section 8C. The no-build alternative is considered the no-action alternative and is not to construct Section 8B. This volume of the ER, which consists of Appendices A, B, and C, assesses the potential geologic impacts of the proposed Section 8B construction, presents the results of the Section 8B soil survey, and describes the water quality studies and analyses performed for the ER. The following summary sections provide information for geology, soils, and water quality.

  16. Photospheric Magnetic Free Energy Density of Solar Active Regions

    Zhang, Hongqi

    2016-01-01

    We present the photospheric energy density of magnetic fields in two solar active regions inferred from observational vector magnetograms, and compare it with the possible different defined energy parameters of magnetic fields in the photosphere. We analyze the magnetic fields in active region NOAA 6580-6619-6659 and 11158. It is noticed that the quantity 1/4pi Bn.Bp is an important energy parameter that reflects the contribution of magnetic shear on the difference between the potential magnetic field (Bp) and non-potential one (Bn), and also the contribution to the free magnetic energy near the magnetic neutral lines in the active regions. It is found that the photospheric mean magnetic energy density changes obviously before the powerful solar flares in the active region NOAA 11158, it is consistent with the change of magnetic fields in the lower atmosphere with flares.

  17. Distribution of Electric Currents in Solar Active Regions

    Török, Tibor; Titov, Viacheslav S; Archontis, Vasilis; Mikić, Zoran; Linton, Mark G; Dalmasse, Kévin; Aulanier, Guillaume; Kliem, Bernhard

    2014-01-01

    There has been a long-lasting debate on the question of whether or not electric currents in solar active regions are neutralized. That is, whether or not the main (or direct) coronal currents connecting the active region polarities are surrounded by shielding (or return) currents of equal total value and opposite direction. Both theory and observations are not yet fully conclusive regarding this question, and numerical simulations have, surprisingly, barely been used to address it. Here we quantify the evolution of electric currents during the formation of a bipolar active region by considering a three-dimensional magnetohydrodynamic simulation of the emergence of a sub-photospheric, current-neutralized magnetic flux rope into the solar atmosphere. We find that a strong deviation from current neutralization develops simultaneously with the onset of significant flux emergence into the corona, accompanied by the development of substantial magnetic shear along the active region's polarity inversion line. After t...

  18. Observational Study of Solar Magnetic Active Phenomena

    Hongqi Zhang

    2006-06-01

    The electric current separated into two parts reflected the quantative properties of heterogeneity and chirality of magnetic field, and defined them as the shear and twist components of current. We analyze the basic configuration and evolution of superactive region NOAA 6580-6619-6659. It is found that the contribution of the twist component of current cannot be reflected in the normal analysis of the magnetic shear and gradient of the active regions. The observational evidence of kink magnetic ropes generated from the subatmosphere cannot be found completely in some super delta active regions.

  19. Solar Rotation Rate During the Cycle 24 Minimum in Activity

    Antia, H. M.; Basu, Sarbani

    2010-01-01

    The minimum of solar cycle 24 is significantly different from most other minima in terms of its duration as well as its abnormally low levels of activity. Using available helioseismic data that cover epochs from the minimum of cycle 23 to now, we study the differences in the nature of the solar rotation between the minima of cycles 23 and 24. We find that there are significant differences between the rotation rates during the two minima. There are differences in the zonal-flow pattern too. We...

  20. Manifestation of solar activity processes in the Earth ozone layer

    Statistical analysis of total ozone and its vertical distribution was carried out on the base of data obtained by rocket soundings with the aim to reveal influence of solar activity. THe coherence between monthly mean total ozone data series for six latitudinal zones in the Northern Hemisphere and solar spots has weak but steady maxima for 9 and 13-15 years periods of oscillations. The value of coherence does not exceed 0.15 and growth to the higher latitudes. The analysis of ozone profiles for middle latitudes reveals the decrease in ozone concentration between 30-50 km for winter and increase for autumn. 20 refs.; 3 figs

  1. Modeling of the atmospheric response to a strong decrease of the solar activity

    Rozanov, Eugene V.; Egorova, Tatiana A.; Shapiro, Alexander I.; Schmutz, Werner K.

    2012-07-01

    We estimate the consequences of a potential strong decrease of the solar activity using the model simulations of the future driven by pure anthropogenic forcing as well as its combination with different solar activity related factors: total solar irradiance, spectral solar irradiance, energetic electron precipitation, solar protons and galactic cosmic rays. The comparison of the model simulations shows that introduced strong decrease of solar activity can lead to some delay of the ozone recovery and partially compensate greenhouse warming acting in the direction opposite to anthropogenic effects. The model results also show that all considered solar forcings are important in different atmospheric layers and geographical regions. However, in the global scale the solar irradiance variability can be considered as the most important solar forcing. The obtained results constitute probably the upper limit of the possible solar influence. Development of the better constrained set of future solar forcings is necessary to address the problem of future climate and ozone layer with more confidence.

  2. Quasi-biennial modulation of solar neutrino flux: connections with solar activity

    Vecchio, A.; Laurenza, M.; D'alessi, L.; Carbone, V.; Storini, M.

    2011-12-01

    A quasi-biennial periodicity has been recently found (Vecchio et al., 2010) in the solar neutrino flux, as detected at the Homestake experiment, as well as in the flux of solar energetic protons, by means of the Empirical Modes Decomposition technique. Moreover, both fluxes have been found to be significantly correlated at the quasi-biennial timescale, thus supporting the hypothesis of a connection between solar neutrinos and solar activity. The origin of this connection is investigated, by modeling how the standard Mikheyev-Smirnov-Wolfenstein (MSW) effect (the process for which the well-known neutrino flavor oscillations are modified in passing through the material) could be influenced by matter fluctuations. As proposed by Burgess et al., 2004, by introducing a background magnetic field in the helioseismic model, density fluctuations can be excited in the radiative zone by the resonance between helioseismic g-modes and Alfvén waves. In particular, with reasonable values of the background magnetic field (10-100 kG), the distance between resonant layers could be of the same order of neutrino oscillation length. We study the effect over this distance of a background magnetic field which is variable with a ~2 yr period, in agreement with typical variations of solar activity. Our findings suggest that the quasi-biennial modulation of the neutrino flux is theoretically possible as a consequence of the magnetic field variations in the solar interior. A. Vecchio, M. Laurenza, V. Carbone, M. Storini, The Astrophysical Journal Letters, 709, L1-L5 (2010). C. Burgess, N. S. Dzhalilov, T. I. Rashba, V., B.Semikoz, J. W. F. Valle, Mon. Not. R. Astron. Soc., 348, 609-624 (2004).

  3. Long-term solar activity influences on South American rivers

    Mauas, Pablo; Flamenco, Eduardo

    2010-01-01

    River streamflows are excellent climatic indicators since they integrate precipitation over large areas. Here we follow up on our previous study of the influence of solar activity on the flow of the Parana River, in South America. We find that the unusual minimum of solar activity in recent years have a correlation on very low levels in the Parana's flow, and we report historical evidence of low water levels during the Little Ice Age. We also study data for the streamflow of three other rivers (Colorado, San Juan and Atuel), and snow levels in the Andes. We obtained that, after eliminating the secular trends and smoothing out the solar cycle, there is a strong positive correlation between the residuals of both the Sunspot Number and the streamflows, as we obtained for the Parana. Both results put together imply that higher solar activity corresponds to larger precipitation, both in summer and in wintertime, not only in the large basin of the Parana, but also in the Andean region north of the limit with Patago...

  4. 17 CFR 270.8b-12 - Requirements as to paper, printing and language.

    2010-04-01

    ..., printing and language. 270.8b-12 Section 270.8b-12 Commodity and Securities Exchanges SECURITIES AND... Requirements as to paper, printing and language. (a) Registration statements and reports shall be filed on good... and reports shall be in the English language. If any exhibit or other paper or document filed with...

  5. Some Daytime Activities in Solar Astronomy

    Burin, Michael J.

    2016-01-01

    This century's transits of Venus (2004, 2012) captured significant public attention, reminding us that the wonders of astronomy need not be confined to the night. And while nighttime telescope viewing gatherings (a.k.a. "star parties") are perennially popular, astronomy classes are typically held in the daytime. The logistics of coordinating students outside of class can often be problematic, leading to dark-sky activities that are relegated to extra credit for only those who can attend.

  6. Infrared Photometry of Solar Active Regions

    Μ. Sobotka; Μ. V'azquez; Μ. S'anchez Cuberes; J. A. Bonet; A. Hanslmeier

    2000-09-01

    Simultaneous time series of broad-band images of two active regions close to the disk center were acquired at the maximum (0.80 m) and minimum (1.55 m) continuum opacities. Dark faculae are detected in images obtained as weighted intensity differences between both wave-length bands. The elements of quiet regions can be clearly distinguished from those of faculae and pores in scatter plots of brightness temperatures. There is a smooth transition between faculae and pores in the scatter plots. These facts are interpreted in terms of the balance between the inhibition of convective energy transport and the lateral radiative heating.

  7. Very Large Array (VLA) observations of solar active regions

    Very Large Array (VLA) synthesis maps of the total intensity and the circular polarization of three active regions at 6 cm wavelength are presented. The radiation from each active region is dominated by a few intense cores with angular sizes of approximately 0.5', brightness temperatures of approximately 106 K, and degrees of circular polarization of 30 to 90%. Some of the core sources within a given active region exhibit opposite senses of circular polarization, suggesting the feet of magnetic dipoles, and the high brightness temperatures suggest that these magnetic structures belong to the low solar corona. Comparisons between the VLA maps of circular polarization and Zeeman effect magnetograms of the lower lying photosphere are presented. There is an excellent correlation between the magnetic structures inferred by the two methods, indicating that synthesis maps of circular polarization at 6 cm can be used to delineate magnetic structures in the low solar corona. (Auth.)

  8. Variation of North-South Asymmetry of Solar Flare Index and Associated Solar Activity

    A. B. BHATTACHARYA

    2012-07-01

    Full Text Available The unequal distributions of various aspects of solar activity between the north and south hemisphere of the Sun have been reported in the paper. When we consider north and south asymmetries of both sunspot area and solar flare indices over the cycles 20 to 23 it is noted that (i there are large variations both in northern and southern sunspot areas, (ii both hemispheres have an asymmetric behavior in terms of a solar activity measure, (iiisunspot areas in northern and southern hemispheres exhibit 11 year periodicity when they were analyzed separately, (iv asymmetry at the end of prolonged cycle 23 is unusually high, (v the northern hemisphere is dominant up to 2001 but thereafter the southern hemisphere takes over from 2002 to the end of solar cycle 23 and then the northern hemisphere dominates in the beginning of cycle 24, (vi yearly plot of flare index reveals that the northern and southern hemisphere is not in phase wherein the northern hemisphere leads in phase by 2 years with two adjacent peaks.

  9. Solar activity impact on the Earth’s upper atmosphere

    Parisi Mario

    2013-02-01

    Full Text Available The paper describes results of the studies devoted to the solar activity impact on the Earth’s upper atmosphere and ionosphere, conducted within the frame of COST ES0803 Action. Aim: The aim of the paper is to represent results coming from different research groups in a unified form, aligning their specific topics into the general context of the subject. Methods: The methods used in the paper are based on data-driven analysis. Specific databases are used for spectrum analysis, empirical modeling, electron density profile reconstruction, and forecasting techniques. Results: Results are grouped in three sections: Medium- and long-term ionospheric response to the changes in solar and geomagnetic activity, storm-time ionospheric response to the solar and geomagnetic forcing, and modeling and forecasting techniques. Section 1 contains five subsections with results on 27-day response of low-latitude ionosphere to solar extreme-ultraviolet (EUV radiation, response to the recurrent geomagnetic storms, long-term trends in the upper atmosphere, latitudinal dependence of total electron content on EUV changes, and statistical analysis of ionospheric behavior during prolonged period of solar activity. Section 2 contains a study of ionospheric variations induced by recurrent CIR-driven storm, a case-study of polar cap absorption due to an intense CME, and a statistical study of geographic distribution of so-called E-layer dominated ionosphere. Section 3 comprises empirical models for describing and forecasting TEC, the F-layer critical frequency foF2, and the height of maximum plasma density. A study evaluates the usefulness of effective sunspot number in specifying the ionosphere state. An original method is presented, which retrieves the basic thermospheric parameters from ionospheric sounding data.

  10. Solar activity impact on the Earth's upper atmosphere

    Kutiev, Ivan; Tsagouri, Ioanna; Perrone, Loredana; Pancheva, Dora; Mukhtarov, Plamen; Mikhailov, Andrei; Lastovicka, Jan; Jakowski, Norbert; Buresova, Dalia; Blanch, Estefania; Andonov, Borislav; Altadill, David; Magdaleno, Sergio; Parisi, Mario; Miquel Torta, Joan

    2013-02-01

    The paper describes results of the studies devoted to the solar activity impact on the Earth's upper atmosphere and ionosphere, conducted within the frame of COST ES0803 Action. Aim: The aim of the paper is to represent results coming from different research groups in a unified form, aligning their specific topics into the general context of the subject. Methods: The methods used in the paper are based on data-driven analysis. Specific databases are used for spectrum analysis, empirical modeling, electron density profile reconstruction, and forecasting techniques. Results: Results are grouped in three sections: Medium- and long-term ionospheric response to the changes in solar and geomagnetic activity, storm-time ionospheric response to the solar and geomagnetic forcing, and modeling and forecasting techniques. Section 1 contains five subsections with results on 27-day response of low-latitude ionosphere to solar extreme-ultraviolet (EUV) radiation, response to the recurrent geomagnetic storms, long-term trends in the upper atmosphere, latitudinal dependence of total electron content on EUV changes, and statistical analysis of ionospheric behavior during prolonged period of solar activity. Section 2 contains a study of ionospheric variations induced by recurrent CIR-driven storm, a case-study of polar cap absorption due to an intense CME, and a statistical study of geographic distribution of so-called E-layer dominated ionosphere. Section 3 comprises empirical models for describing and forecasting TEC, the F-layer critical frequency foF2, and the height of maximum plasma density. A study evaluates the usefulness of effective sunspot number in specifying the ionosphere state. An original method is presented, which retrieves the basic thermospheric parameters from ionospheric sounding data.

  11. Accumulation in Dasuopu ice core in Qinghai-Tibet Plateau and solar activity

    2000-01-01

    The time series of accumulation in recent 300 years correlated well with solar activity in Dasuopu ice core. Results of spectrum analysis on the accumulation time series of the Dasuopu ice core shows that there are some periods that coincide with the periods of solar activity. By comparing the long-time change trend of the accumulation in the Dasuopu ice core with various kinds of indexes of solar activity intensity, a negative correlation is found between the trend and solar activity.

  12. VARIATIONS OF SOLAR ROTATION AND SUNSPOT ACTIVITY

    The continuous wavelet transformation is used to study the temporal variations of the rotational cycle length of daily sunspot numbers from 1849 January 1 to 2010 February 28, from a global point of view. The rotational cycle length of the Sun is found to have a secular trend, which statistically shows a linear decrease by about 0.47 days during the time interval considered. The empirical mode decomposition analysis of the temporal variations of the rotational cycle length shows an acceleration trend for the surface rotation rate from cycles 11 to 19, but a deceleration trend from the beginning of cycle 20 onward. We cannot determine whether the rotation rate around the maximum times of the Schwable cycles should be faster or slower than that around the minimum times, implying no Schwable cycle in the long-term variations of rotation. The results obtained are compared to those from the literature. It is inferred that the variation of the rotational cycle length may be related to the variation of sunspot activity in the long run.

  13. Study of Distribution and Asymmetry of Solar Active Prominences During Solar Cycle 23

    Joshi, Navin Chandra; Pande, Seema; Pande, Bimal; Pandey, Kavita

    2009-01-01

    In this paper we present the results of a study of the spatial distribution and asymmetry of solar active prominences (SAP) for the period 1996-2007 (solar cycle 23). For more meaningful statistical analysis we have analysed the distribution and asymmetry of SAP in two subdivisions viz. Group1 (ADF, APR, DSF, CRN, CAP) and Group2 (AFS, ASR, BSD, BSL, DSD, SPY, LPS). The north-south (N-S) latitudinal distribution shows that the SAP events are most prolific in the 21-30degree slice in the northern and southern hemispheres and east-west (E-W) longitudinal distribution study shows that the SAP events are most prolific (best visible) in the 81-90degree slice in the eastern and western hemispheres. It has been found that the SAP activity during this cycle is low compared to previous solar cycles. The present study indicates that during the rising phase of the cycle the number of SAP events were roughly equal on the north and south hemispheres. However, activity on the southern hemisphere has been dominant since 199...

  14. Online educative activities for solar ultraviolet radiation based on measurements of cloud amount and solar exposures.

    Parisi, A V; Downs, N; Turner, J; Amar, A

    2016-09-01

    A set of online activities for children and the community that are based on an integrated real-time solar UV and cloud measurement system are described. These activities use the functionality of the internet to provide an educative tool for school children and the public on the influence of cloud and the angle of the sun above the horizon on the global erythemal UV or sunburning UV, the diffuse erythemal UV, the global UVA (320-400nm) and the vitamin D effective UV. Additionally, the units of UV exposure and UV irradiance are investigated, along with the meaning and calculation of the UV index (UVI). This research will help ensure that children and the general public are better informed about sun safety by improving their personal understanding of the daily and the atmospheric factors that influence solar UV radiation and the solar UV exposures of the various wavebands in the natural environment. The activities may correct common misconceptions of children and the public about UV irradiances and exposure, utilising the widespread reach of the internet to increase the public's awareness of the factors influencing UV irradiances and exposures in order to provide clear information for minimizing UV exposure, while maintaining healthy, outdoor lifestyles. PMID:27450297

  15. A Statistical Analysis of Solar Surface Indices Through the Solar Activity Cycles 21-23

    Goker, Umit Deniz; Nutku, Ferhat; Priyal, Muthu

    2016-01-01

    Variations of total solar irradiance (TSI), magnetic field, Ca II K-flux, faculae and plage areas due to the number and the type of sunspots/sunspot groups (SGs) are well established by using ground based data from various centers such as Solar Irradiance Platform, Stanford Data (SFO), Kodaikanal data (KKL) and National Geographical Data Center (NGDC) Homepage, respectively. We applied time series analysis for extracting the data over the descending phases of solar activity cycles (SACs) 21, 22 and 23, and the ascending phases 22 and 23 of SACs, and analyzed the selected data using the Python programming language. Our detailed analysis results suggest that there is a stronger correlation between solar surface indices and the changes in the relative portion of the small and large SGs. This somewhat unexpected finding suggest that plage regions decreased in a lower values in spite of the higher number of large SGs in SAC 23 while Ca II K-flux did not decrease by large amount or it was comparable with SAC 22 for...

  16. Solar activity: nowcasting and forecasting at the SIDC

    D. Berghmans

    2005-11-01

    Full Text Available The Solar Influences Data analysis Center (SIDC is the World Data Center for the production and the distribution of the International Sunspot Index, coordinating a network of about 80 stations worldwide. From this core activity, the SIDC has grown in recent years to a European center for nowcasting and forecasting of solar activity on all timescales. This paper reviews the services (data, forecasts, alerts, software that the SIDC currently offers to the scientific community. The SIDC operates instruments both on the ground and in space. The USET telescope in Brussels produces daily white light and Hα images. Several members of the SIDC are co-investigators of the EIT instrument onboard SOHO and are involved in the development of the next generation of Europe's solar weather monitoring capabilities. While the SIDC is staffed only during day-time (7 days/week, the monitoring service is a 24 h activity thanks to the implementation of autonomous software for data handling and analysis and the sending of automated alerts. We will give an overview of recently developed techniques for visualization and automated analysis of solar images and detection of events significant for space weather (e.g. CMEs or EIT waves. As part of the involvement of the SIDC in the ESA Pilot Project for Space Weather Applications we have developed services dedicated to the users of the Global Positioning System (GPS. As a Regional Warning Center (RWC of the International Space Environment Service (ISES, the SIDC produces daily forecasts of flaring probability, geomagnetic activity and 10.7 cm radio flux. The accuracy of these forecasts will be investigated through an in-depth quality analysis.

  17. Common 22-year cycles of Earth rotation and solar activity

    Chapanov, Y.; Vondrák, Jan; Ron, Cyril

    Cambridge: Cambridge University Press, 2010 - (Kosovichev, A.; Andrei, A.; Rozelot, J.), s. 404-406. (IAU Symposium Proceedings Series. S264). ISBN 978-0-521-76492-6. ISSN 1743-9213. [Symposium of the International Astronomical Union /264./. Rio de Janeiro (BR), 03.08.2009-07.08.2009] Institutional research plan: CEZ:AV0Z10030501 Keywords : Sun activity * sunspots * solar-terrestrial relations Subject RIV: AC - Archeology, Anthropology, Ethnology

  18. The influence of solar wind turbulence on geomagnetic activity

    Jankovičová, Dana; Vörös, Zoltán; Šimkanin, Ján

    2008-01-01

    Roč. 15, č. 1 (2008), s. 53-59. ISSN 1023-5809 R&D Projects: GA AV ČR KJB300420509 Grant ostatní: INTAS Foundation(CH) 06-1000017-8943 Institutional research plan: CEZ:AV0Z30420517; CEZ:AV0Z30120515 Keywords : Solar wind * Turbulence * Geomagnetic activity Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.022, year: 2008 http://www.nonlin-processes-geophys.net/15/53/2008/

  19. Solar activity impact on the Earth’s upper atmosphere

    Kutiev, I.; Tsagouri, I.; Perrone, L.; Pancheva, D.; Mukhtarov, P.; Mikhailov, A.; Laštovička, Jan; Jakowski, N.; Burešová, Dalia; Blanch, E.; Andonov, B.; Altadill, D.; Magdaleno, S.; Parisi, M.; Torta, J. M.

    2013-01-01

    Roč. 3, February (2013), A06/1-A06/21. ISSN 2115-7251 Grant ostatní: COST(XE) ES0803 Institutional support: RVO:68378289 Keywords : ionosphere * solar activity * storm * total electron content * data analysis Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 2.519, year: 2013 http://www.swsc-journal.org/index.php?option=com_article&access=doi&doi=10.1051/swsc/2013028&Itemid=129

  20. Sign singularity and flares in solar active region NOAA 11158

    Sorriso-Valvo, Luca; De Vita, Gaetano; Kazachenko, Maria D.; Krucker, Sam; Primavera, Leonardo; Servidio, Sergio; Vecchio, Antonio; Welsch, Brian T.; Fisher, George H.; Lepreti, Fabio; Carbone, Vincenzo

    2015-01-01

    Solar Active Region NOAA 11158 has hosted a number of strong flares, including one X2.2 event. The complexity of current density and current helicity are studied through cancellation analysis of their sign-singular measure, which features power-law scaling. Spectral analysis is also performed, revealing the presence of two separate scaling ranges with different spectral index. The time evolution of parameters is discussed. Sudden changes of the cancellation exponents at the time of large flar...

  1. The solar activity cycle physical causes and consequences

    Hudson, Hugh; Petrovay, Kristóf; Steiger, Rudolf

    2015-01-01

    A collection of papers edited by four experts in the field, this book sets out to describe the way solar activity is manifested in observations of the solar interior, the photosphere, the chromosphere, the corona and the heliosphere. The 11-year solar activity cycle, more generally known as the sunspot cycle, is a fundamental property of the Sun.  This phenomenon is the generation and evolution of magnetic fields in the Sun’s convection zone, the photosphere.  It is only by the careful enumeration and description of the phenomena and their variations that one can clarify their interdependences.   The sunspot cycle has been tracked back about four centuries, and it has been recognized that to make this data set a really useful tool in understanding how the activity cycle works and how it can be predicted, a very careful and detailed effort is needed to generate sunspot numbers.  This book deals with this topic, together with several others that present related phenomena that all indicate the physical pr...

  2. Dayside Auroral Activity During Solar Maximum and Minimum Periods

    Rawie, M.; Fasel, G. J.; Flicker, J.; Angelo, A.; Bender, S.; Alyami, M.; Sibeck, D. G.; Sigernes, F.; Lorentzen, D. A.; Green, D.

    2014-12-01

    It is well documented that the dayside auroral oval shifts equatorward when the interplanetary magnetic field (IMF) Bz-component turns southward [Burch, 1973; Akasofu, 1977; Horwitz and Akasofu, 1977; Sandholt et al., 1986, 1988]. During these periods of oval expansion dayside transients are observed to move away from the poleward edge of the auroral oval and drift poleward. These poleward-moving auroral forms are believed to be ionospheric signatures of dayside merging. The dayside auroral oval usually begins to contract when the interplanetary magnetic field turns sharply northward, Bz>0. Eighteen years of meridian scanning photometer (MSP) data from the Kjell Henriksen Observatory in Longyearbyen, Norway are analyzed. During the boreal winter the Sun is several degrees below the horizon. This permits optical observations throughout the daytime period. The MSP Data is selected two hours before and after local noon in Longyearbeyn. Solar wind data (solar wind pressure and speed, along with the IMF Bx, By, Bz components) are collected for each interval and combined with the MSP observations. This data is then separated using solar maximum and minimum periods. Auroral activity (oval expansions and contractions along with the frequency and number of poleward-moving auroral forms) is documented for both solar maximum and minimum periods.

  3. Forecasting the Peak of the Present Solar Activity Cycle

    Hamid, Rabab; Marzouk, Beshir

    2016-07-01

    Solar forecasting of the level of sun Activity is very important subject for all space programs. Most predictions are based on the physical conditions prevailing at or before the solar cycle minimum preceding the maximum in question. Our aim is to predict the maximum peak of cycle 24 using precursor techniques in particular those using spotless event, geomagnetic aa min. index and solar flux F10.7. Also prediction of exact date of the maximum (Tr) is taken in consideration. A study of variation over previous spotless event for cycles 7-23 and that for even cycles (8-22) are carried out for the prediction. Linear correlation between RM and spotless event around the preceding minimum gives RM24t = 101.9with rise time Tr = 4.5 Y. For the even cycles RM24e = 108.3 with rise time Tr = 3.9 Y. Based on the average aa min. index for the year of sunspot minimum cycles (13 - 23), we estimate the expected amplitude for cycle 24 to be RMaa = 116.5 for both the total and even cycles. Application of the data of solar flux F10.7 which cover only cycles (19-23) was taken in consideration and gives predicted maximum amplitude R24 10.7 = 146, which are over estimation. Our result indicating a somewhat weaker cycle 24 as compared to cycles 21-23.

  4. Active other worlds in the Solar System and beyond

    Forget, François

    2016-04-01

    Over the past decades, space exploration has moved planetology from the field of astronomy to the disciplines of geosciences. A fleet of spacecrafts have discovered and study tens of worlds in our solar system and beyond. Everywhere, we have been surprised by the diversity and the vigour of the geophysical activity, from volcanic eruptions to plasma waves... Every scientists present at EGU could -and should- be interested in the extraterrestrial processes that are discovered and analyzed elsewhere. In our solar system, a variety of clouds and fluid dynamical phenomena can be studied in six terrestrial atmospheres and on four giant planets. Active glaciers are found on Mars and Pluto. Rivers and lakes have sculpted the surface of Titan and Mars. Sometime, we can even study geophysical activity with no equivalent on our planet: ice caps made of frozen atmosphere that erupt in geysers, hazes formed by organic polymers which can completely shroud a moon, etc. We study these active worlds because we are curious and wish to understand our universe and our origins. However, more than ever, two specific motivations drive solar system geosciences in 2016: Firstly, as we become more and more familiar with the other worlds around us, we can use them to better understand our own planet. Throughout the solar system, we can access to data that are simply not available on the Earth, or study active processes that are subtle on Earth but of greater importance elsewhere, so that we can better understand them. Many geophysical concepts and tools developed for the Earth can also be tested on other planets. For instance the numerical Climate Models used to assess Earth's future climate change are applied to other planets. Much is learned from such experiments. Secondly, the time has come to generalize the fundamental lessons that we have learned from the examples in the solar system (including the Earth) to address the countless scientific questions that are -and will be- raised by

  5. Solar-Type Activity: Epochs of Cycle Formation

    Katsova, M M; Livshits, M A

    2015-01-01

    The diagram of indices of coronal and chromospheric activity allowed us to reveal stars where solar-type activity appears and regular cycles are forming. Using new consideration of a relation between coronal activity and the rotation rate, together with new data on the ages of open clusters, we estimate the age of the young Sun corresponding to the epoch of formation of its cycle. The properties of the activity of this young Sun, with an age slightly older than one billion years, are briefly discussed. An analysis of available data on the long-term regular variability of late-type stars leads to the conclusion that duration of a cycle associated with solar-type activity increases with the deceleration of the stellar rotation; i.e., with age. New data on the magnetic fields of comparatively young G stars and changes in the role of the large-scale and the local magnetic fields in the formation of the activity of the young Sun are discussed. Studies in this area aim to provide observational tests aimed at identi...

  6. Prediction of solar activity from solar background magnetic field variations in cycles 21-23

    Shepherd, Simon J. [School of Engineering, University of Bradford, Bradford, BD7 1DP (United Kingdom); Zharkov, Sergei I. [Department of Physics and Mathematics, University of Hull, Kingston upon Tyne, HU6 7RS (United Kingdom); Zharkova, Valentina V., E-mail: s.j.shepherd@brad.ac.uk, E-mail: s.zharkov@hull.ac.uk, E-mail: valentina.zharkova@northumbria.ac.uk [Department of Mathematics and Information Systems, University of Northumbria, Newcastle upon Tyne, NE2 8ST (United Kingdom)

    2014-11-01

    A comprehensive spectral analysis of both the solar background magnetic field (SBMF) in cycles 21-23 and the sunspot magnetic field in cycle 23 reported in our recent paper showed the presence of two principal components (PCs) of SBMF having opposite polarity, e.g., originating in the northern and southern hemispheres, respectively. Over a duration of one solar cycle, both waves are found to travel with an increasing phase shift toward the northern hemisphere in odd cycles 21 and 23 and to the southern hemisphere in even cycle 22. These waves were linked to solar dynamo waves assumed to form in different layers of the solar interior. In this paper, for the first time, the PCs of SBMF in cycles 21-23 are analyzed with the symbolic regression technique using Hamiltonian principles, allowing us to uncover the underlying mathematical laws governing these complex waves in the SBMF presented by PCs and to extrapolate these PCs to cycles 24-26. The PCs predicted for cycle 24 very closely fit (with an accuracy better than 98%) the PCs derived from the SBMF observations in this cycle. This approach also predicts a strong reduction of the SBMF in cycles 25 and 26 and, thus, a reduction of the resulting solar activity. This decrease is accompanied by an increasing phase shift between the two predicted PCs (magnetic waves) in cycle 25 leading to their full separation into the opposite hemispheres in cycle 26. The variations of the modulus summary of the two PCs in SBMF reveals a remarkable resemblance to the average number of sunspots in cycles 21-24 and to predictions of reduced sunspot numbers compared to cycle 24: 80% in cycle 25 and 40% in cycle 26.

  7. Solar activity and climate change during the 1750 A.D. solar minimum

    Bard, Edouard; Baroni, Mélanie; Aster Team

    2015-04-01

    The number of sunspots and other characteristics have been widely used to reconstruct the solar activity beyond the last three decades of accurate satellite measurements. It has also been possible to reconstruct the long-term solar behavior by measuring the abundance on Earth of cosmogenic nuclides such as carbon 14 and beryllium 10. These isotopes are formed by the interaction of galactic cosmic rays with atmospheric molecules. Accelerator mass spectrometry is used to measure the abundance of these isotopes in natural archives such as polar ice (for 10Be), tree rings and corals (for 14C). Over the last millennium, the solar activity has been dominated by alternating active and quiet periods, such as the Maunder Minimum, which occurred between 1645 and 1715 A.D. The climate forcing of this solar variability is the subject of intense research, both because the exact scaling in terms of irradiance is still a matter of debate and because other solar variations may have played a role in amplifying the climatic response. Indeed, the past few decades of accurate solar measurements do not include conditions equivalent to an extended solar minimum. A further difficulty of the analysis lies in the presence of other climate forcings during the last millennium, which are superimposed on the solar variations. Finally, the inherent precision of paleotemperature proxies are close to the signal amplitude retrieved from various paleoclimate archives covering the last millennium. Recent model-data comparisons for the last millennium have led to the conclusion that the solar forcing during this period was minor in comparison to volcanic eruptions and greenhouse gas concentrations (e.g. Schurer et al. 2013 J. Clim., 2014 Nat. Geo.). In order to separate the different forcings, it is useful to focus on a temperature change in phase with a well-documented solar minimum so as to maximize the response to this astronomical forcing. This is the approach followed by Wagner et al. (2005 Clim

  8. Activity trends in young solar-type stars

    Lehtinen, Jyri; Hackman, Thomas; Kajatkari, Perttu; Henry, Gregory W

    2015-01-01

    We apply the Continuous Period Search (CPS) time series analysis method on Johnson B and V band photometry of 21 young and active solar-type, collected over 16 to 27 years and characterize the behaviour of their activity. Using the CPS method, differential rotation could be estimated from the observed variations of the photometric rotation period. Active longitudes were retrieved by applying a non-parametric period search on the light curve minimum epochs, and activity cycles by applying a secondary period search on the modelled light curve mean and amplitude values. We supplemented the time series results by calculating new $\\log{R'_{\\rm HK}}$ emission indices for the stars from high resolution spectroscopy. The measurements of the photometric rotation period variations point to a trend of increasing differential rotation coefficients towards longer rotation periods but do not reveal any dependence from the effective temperature of the stars. The secondary period searches revealed activity cycles in 18 of th...

  9. Foothills Parkway Section 8B Final Environmental Report, Volume 6, Appendix N

    Blasing, T.J.; Cada, G.F.; Carer, M.; Chin, S.M.; Dickerman, J.A.; Etnier, D.A.; Gibson, R.; Harvey, M.; Hatcher, B.; Lietzske, D.; Mann, L.K.; Mulholland, P.J.; Petrich, C.H.; Pounds, L.; Ranney, J.; Reed, R.M.; Ryan, P.F.; Schweitzer, M.; Smith, D.; Thomason, P.; Wade, M.C.

    1999-07-01

    In 1994, Oak Ridge National Laboratory (ORNL) was tasked by the National Park Service (NPS) to prepare an Environmental Report (ER) for Section 8B of the Foothills Parkway in the Great Smoky Mountains National Park (GSMNP). Section 8B represents 27.7 km (14.2 miles) of a total of 115 km (72 miles) of the planned Foothills Parkway and would connect the Cosby community on the east to the incorporated town of Pittman Center to the west. The major deliverables for the project are listed. From August 1995 through October 1996, NPS, GSMNP, and ORNL staff interacted with Federal Highway Administration staff to develop a conceptual design plan for Section 8B with the intent of protecting critical resources identified during the ER process to the extent possible. In addition, ORNL arranged for bioengineering experts to discuss techniques that might be employed on Section 8B with NPS, GSMNP, and ORNL staff during September 1996. For the purposes of this ER, there are two basic alternatives under consideration: (1) a build alternative and (2) a no-build alternative. Within the build alternative are a number of options including constructing Section 8B with no interchanges, constructing Section 8B with an interchange at SR 416 or U.S. 321, constructing Section 8B with a spur road on Webb Mountain, and considering operation of Section 8B both before and after the operation of Section 8C. The no-build alternative is considered the no-action alternative and is not to construct Section 8B. This volume of the ER documents the results of the architectural, historical, and cultural resources assessment for the entire Section 8B ROW that was completed in May 1995 to document the architectural, historical, and cultural resources located within the project area. The assessment included evaluation of the potential for cultural (i.e., rural historic) landscapes in the area of the ROW. The assessment showed that one National Register-listed property is located 0.3 mile south of the ROW

  10. Coulomb dissociation of {sup 8}B at 254 A MeV

    Suemmerer, K.; Boue, F.; Baumann, T.; Geissel, H.; Hellstroem, M.; Koczon, P.; Schwab, E.; Schwab, W.; Senger, P.; Surowiecz, A. [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany); Iwasa, N.; Ozawa, A. [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany)]|[RIKEN Institute of Physical and Chemical Research, Saitama (Japan); Surowka, G. [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany)]|[Jagiellonian Univ., Krakow (Poland). Inst. of Physics; Blank, B.; Czajkowski, S.; Marchand, C.; Pravikoff, M.S. [Centre d`Etudes Nucleaires de Bordeaux-Gradignan, 33 (France); Foerster, A.; Lauer, F.; Oeschler, H.; Speer, J.; Sturm, C.; Uhlig, F.; Wagner, A. [Technische Univ. Darmstadt (Germany); Gai, M. [Connecticut Univ., Storrs, CT (United States). Dept. of Physics; Grosse, E. [Inst. fuer Kern- und Hadronenphysik, Forschungszentrum Rossendorf, Dresden (Germany); Kohlmeyer, B. [Philipps Univ., Marburg (Germany). Fachbereich Physik; Kulessa, R.; Walus, W. [Jagiellonian Univ., Krakow (Poland). Inst. of Physics; Motobayashi, T. [Rikkyo Univ., Tokyo (Japan). Dept. of Physics; Teranishi, T. [RIKEN Institute of Physical and Chemical Research, Saitama (Japan)

    1998-06-01

    As an alternative method for determining the astrophysical S-factor for the {sup 7}Be(p,{gamma}){sup 8}B reaction we have measured the Coulomb dissociation of {sup 8}B at 254 A MeV. From our preliminary results, we obtain good agreement with both the accepted direct-reaction measurements and the low-energy Coulomb dissociation study of Iwasa et al. performed at about 50 A MeV. (orig.)

  11. Solar active envelope module with an adjustable transmittance/absorptance

    C. Villasante Villasante

    2015-06-01

    Full Text Available A solar active envelope module with a high flexibility degree is proposed in this paper. The transparent module controls the day-lighting of the room, improving the indoor environment, while absorbing the superfluous solar energy inside. That energy is used to increase the efficiency of heating, ventilation, and the air-conditioning (HVAC system of the building. This is carried out through a fine control of the absorptance of the envelope module. The active envelope module consists of three glazed chambers with advanced coatings and frames to assure a minimum thermal transmittance while allowing transparency. A fluid containing heat-absorbing nanoparticles flows inside the central chamber and is heated up due to the impinging solar energy. Unlike other systems proposed in the past, which included transparency control systems based on complex filters and chemical processes, the absorption of the module is controlled by the variation of the thickness of the central chamber with a mechanical device. That is, varying the thickness of the central chamber, it allows controlling the absorptance of the whole system and, as a result, indoor day-lighting and thermal loads. Therefore, a new system is proposed that enables to:  

  12. DISTRIBUTION OF ELECTRIC CURRENTS IN SOLAR ACTIVE REGIONS

    There has been a long-standing debate on the question of whether or not electric currents in solar active regions are neutralized. That is, whether or not the main (or direct) coronal currents connecting the active region polarities are surrounded by shielding (or return) currents of equal total value and opposite direction. Both theory and observations are not yet fully conclusive regarding this question, and numerical simulations have, surprisingly, barely been used to address it. Here we quantify the evolution of electric currents during the formation of a bipolar active region by considering a three-dimensional magnetohydrodynamic simulation of the emergence of a sub-photospheric, current-neutralized magnetic flux rope into the solar atmosphere. We find that a strong deviation from current neutralization develops simultaneously with the onset of significant flux emergence into the corona, accompanied by the development of substantial magnetic shear along the active region's polarity inversion line. After the region has formed and flux emergence has ceased, the strong magnetic fields in the region's center are connected solely by direct currents, and the total direct current is several times larger than the total return current. These results suggest that active regions, the main sources of coronal mass ejections and flares, are born with substantial net currents, in agreement with recent observations. Furthermore, they support eruption models that employ pre-eruption magnetic fields containing such currents

  13. Non-Stationary Effects and Cross Correlations in Solar Activity

    Nefedyev, Yuri; Panischev, Oleg; Demin, Sergey

    2016-07-01

    In this paper within the framework of the Flicker-Noise Spectroscopy (FNS) we consider the dynamic properties of the solar activity by analyzing the Zurich sunspot numbers. As is well-known astrophysics objects are the non-stationary open systems, whose evolution are the quite individual and have the alternation effects. The main difference of FNS compared to other related methods is the separation of the original signal reflecting the dynamics of solar activity into three frequency bands: system-specific "resonances" and their interferential contributions at lower frequencies, chaotic "random walk" ("irregularity-jump") components at larger frequencies, and chaotic "irregularity-spike" (inertial) components in the highest frequency range. Specific parameters corresponding to each of the bands are introduced and calculated. These irregularities as well as specific resonance frequencies are considered as the information carriers on every hierarchical level of the evolution of a complex natural system with intermittent behavior, consecutive alternation of rapid chaotic changes in the values of dynamic variables on small time intervals with small variations of the values on longer time intervals ("laminar" phases). The jump and spike irregularities are described by power spectra and difference moments (transient structural functions) of the second order. FNS allows revealing the most crucial points of the solar activity dynamics by means of "spikiness" factor. It is shown that this variable behaves as the predictor of crucial changes of the sunspot number dynamics, particularly when the number comes up to maximum value. The change of averaging interval allows revealing the non-stationary effects depending by 11-year cycle and by inside processes in a cycle. To consider the cross correlations between the different variables of solar activity we use the Zurich sunspot numbers and the sequence of corona's radiation energy. The FNS-approach allows extracting the

  14. Electrically active defects in solar grade multicrystalline silicon

    Dahl, Espen

    2013-01-01

    gettering techniques. It was found that a high density of dislocations provided centres for precipitation of metallic impurities in a substantial part of wafers based on commercially available silicon from the metallurgic route. These precipitates introduce a range of defect levels in the silicon band gap...... distribution of metallic point defects. In addition, it has been proven that introduction of sodium lead to significant recombination activity in silicon. The gettering potential of metallic impurities varied significantly based on the type of material. This is most likely related to the density of......Shortage in high purity silicon feedstock, as a result of the formidable increased demand for solar cell devices during the last two decades, can be mitigated by the introduction of cheaper feedstock of solar grade (So-G) quality. Silicon produced through the metallurgical process route has shown...

  15. Multi-wavelength Observations of Solar Active Region NOAA 7154

    Bruner, M. E.; Nitta, N. V.; Frank. Z. A.; Dame, L.; Suematsu, Y.

    2000-01-01

    We report on observations of a solar active region in May 1992 by the Solar Plasma Diagnostic Experiment (SPDE) in coordination with the Yohkoh satellite (producing soft X-ray images) and ground-based observatories (producing photospheric magnetograms and various filtergrams including those at the CN 3883 A line). The main focus is a study of the physical conditions of hot (T is approximately greater than 3 MK) coronal loops at their foot-points. The coronal part of the loops is fuzzy but what appear to be their footpoints in the transition region down to the photosphere are compact. Despite the morphological similarities, the footpoint emission at 10(exp 5) K is not quantitatively correlated with that at approximately 300 km above the tau (sub 5000) = 1 level, suggesting that the heat transport and therefore magnetic field topology in the intermediate layer is complicated. High resolution imaging observations with continuous temperature coverage are crucially needed.

  16. On the possible relations between solar activities and global seismicity in the solar cycle 20 to 23

    Herdiwijaya, Dhani, E-mail: dhani@as.itb.ac.id [Astronomy Research Division and Bosscha Observatory, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Ganesha 10, Bandung, Indonesia 40132 (Indonesia); Arif, Johan [Geology Research Division, Faculty of Earth Sciences and Technology, Bandung Institute of Technology, Ganesha 10, Bandung, Indonesia 40132 (Indonesia); Nurzaman, Muhamad Zamzam; Astuti, Isna Kusuma Dewi [Astronomy Study Program, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Ganesha 10, Bandung, Indonesia 40132 (Indonesia)

    2015-09-30

    Solar activities consist of high energetic particle streams, electromagnetic radiation, magnetic and orbital gravitational forces. The well-know solar activity main indicator is the existence of sunspot which has mean variation in 11 years, named by solar cycle, allow for the above fluctuations. Solar activities are also related to the space weather affecting all planetary atmospheric variability, moreover to the Earth’s climate variability. Large extreme space and geophysical events (high magnitude earthquakes, explosive volcanic eruptions, magnetic storms, etc.) are hazards for humankind, infrastructure, economies, technology and the activities of civilization. With a growing world population, and with modern reliance on delicate technological systems, human society is becoming increasingly vulnerable to natural hazardous events. The big question arises to the relation between solar forcing energy to the Earth’s global seismic activities. Estimates are needed for the long term occurrence-rate probabilities of these extreme natural hazardous events. We studied connectivity from yearly seismic activities that refer to and sunspot number within the solar cycle 20 to 23 of year 1960 to 2013 (53 years). We found clear evidences that in general high magnitude earthquake events and their depth were related to the low solar activity.

  17. On the possible relations between solar activities and global seismicity in the solar cycle 20 to 23

    Solar activities consist of high energetic particle streams, electromagnetic radiation, magnetic and orbital gravitational forces. The well-know solar activity main indicator is the existence of sunspot which has mean variation in 11 years, named by solar cycle, allow for the above fluctuations. Solar activities are also related to the space weather affecting all planetary atmospheric variability, moreover to the Earth’s climate variability. Large extreme space and geophysical events (high magnitude earthquakes, explosive volcanic eruptions, magnetic storms, etc.) are hazards for humankind, infrastructure, economies, technology and the activities of civilization. With a growing world population, and with modern reliance on delicate technological systems, human society is becoming increasingly vulnerable to natural hazardous events. The big question arises to the relation between solar forcing energy to the Earth’s global seismic activities. Estimates are needed for the long term occurrence-rate probabilities of these extreme natural hazardous events. We studied connectivity from yearly seismic activities that refer to and sunspot number within the solar cycle 20 to 23 of year 1960 to 2013 (53 years). We found clear evidences that in general high magnitude earthquake events and their depth were related to the low solar activity

  18. Impacts of Extended Periods of Low Solar Activity on Climate (Abstract)

    Denig, W. F.

    2016-06-01

    (Abstract only) There has been great interest in determining the length and amplitude of Solar Cycle 24 in recent years, in part due to increasing speculation that the current solar minimum is anomalously quiet and perhaps signaling the beginning of a decreased period of solar activity in the coming decades. We aim to examine the current solar minimum and compare it to previous solar minima in order to: determine if the current minimum shares characteristics with other historically quiet solar minima (sometimes referred to as grand minima); outline the potential consequences of a grand minimum with respect to climate; and predict the future of Solar Cycle 24.

  19. Solar EUV Variability from FISM and SDO/EVE During Solar Minimum, Active, and Flaring Time Periods

    Chamberlin, Phillip C.

    2011-01-01

    The Living With a Star (LWS) Focus Science Team has identified three periods of different solar activity levels for which they will be determining the Earth's Ionosphere and Thermosphere response. Not only will the team be comparing individual models (e.g. FLIP, T1MEGCM, GLOW) outcome driven by the various levels of solar activity, but the models themselves will also be compared. These models all rely on the input solar EUV (0.1 -190 nm) irradiance to drive the variability. The Flare Irradiance Spectral Model (FISM) and the EUV Variability Experiment (EVE) onboard provide the Solar Dynamics Observatory (SDO) provide the most accurate quantification of these irradiances. Presented and discussed are how much the solar EUV irradiance changes during these three scenarios, both as a function of activity and wavelength.

  20. Solar technology assessment project. Volume 4: Solar air conditioning: Active, hybrid and passive

    Yellott, J. I.

    1981-04-01

    The status of absorption cycle solar air conditioning and the Rankine cycle solar cooling system is reviewed. Vapor jet ejector chillers, solar pond based cooling, and photovoltaic compression air conditioning are also briefly discussed. Hybrid solar cooling by direct and indirect evaporative cooling, and dehumidification by desiccation are described and discussed. Passive solar cooling by convective and radiative processes, evaporative cooling by passive processes, and cooling with roof ponds and movable insulation are reviewed. Federal and state involvement in solar cooling is discussed.

  1. An alternative measure of solar activity from detailed sunspot datasets

    Muraközy, Judit; Ludmány, András

    2016-01-01

    The sunspot number is analyzed by using detailed sunspot data, including aspects of observability, sunspot sizes, and proper identification of sunspot groups as discrete entities of the solar activity. The tests show that besides the subjective factors there are also objective causes of the ambiguities in the series of sunspot numbers. To introduce an alternative activity measure the physical meaning of the sunspot number has to be reconsidered. It contains two components whose numbers are governed by different physical mechanisms, this is one source of the ambiguity. This article suggests an activity index, which is the amount of emerged magnetic flux. The only long-term proxy measure is the detailed sunspot area dataset with proper calibration to the magnetic flux amount. The Debrecen sunspot databases provide an appropriate source for the establishment of the suggested activity index.

  2. A comparative analysis of the Army MQ-8B Fire Scout Vertical Takeoff Unmanned Aerial Vehicle (VTUAV) AND Navy MQ-8B manpower and training requirements

    Raymer, Michael K.

    2009-01-01

    Approved for public release, distribution unlimited The recent increased urgency to combat terrorism and asymmetric threats, combined with the environment in which field troops are forced to operate has created a unique demand for non-standard war fighting capabilities. Beginning in 2004, the U.S. Navy, in a joint effort with the U.S. Army, began jointly testing and evaluating the Northrop Grumman MQ-8B Fire Scout Vertical Take Off Unmanned Aerial Vehicle (VTUAV). This platform has sho...

  3. Real Research In The Classroom - Solar Active Longitudes

    Stagg, T.; Gearen, M.; Jacoby, S. H.; Jones, H. P.; Henney, C. J.; Hill, F.

    2000-12-01

    We present a high-school level educational/research module for a project that improves computer and analytical skills and contributes new scientific results to the field of solar astronomy and physics. The module has been developed within the RET (Research Experience for Teachers) program as a new application of a cooperative project between the RBSE (Research-Based Science Education) initiative of the NSF and the NASA Education/Public Outreach program. The research goal is to improve our knowledge of the characteristics of solar active longitudes, where sunspots tend to cluster. In particular, the rotation rate of these regions is poorly known. It is suspected that the active longitude rotation rate (ALRR) is different from the rotation rate of the solar surface. If this is true, the ALRR can be compared with the internal rotation rate deduced by helioseismology providing an estimate of the active region depth. A good determination of the ALRR requires the measurement of the position of thousands of individual active regions, a step best done by interactive examination of images, selection of regions, and determination of heliographic position. These tasks are well-suited for high school students, who are thus provided with a motivation to improve their computer and scientific thinking skills. ScionImage (PC)/NIH Image (Macs) macros for this purpose have been developed which access a CD-ROM of 25 years of NSO/Kitt Peak magnetogram data and laboratory exercises developed previously for classroom use. In the future, a web site will be created for collecting the data from classrooms across the US, and for status reports on the results.

  4. Foothills Parkway Section 8B Final Environmental Report, Volume 3, Appendix D

    Blasing, T.J.; Cada, G.F.; Carer, M.; Chin, S.M.; Dickerman, J.A.; Etnier, D.A.; Gibson, R.; Harvey, M.; Hatcher, B.; Lietzske, D.; Mann, L.K.; Mulholland, P.J.; Petrich, C.H.; Pounds, L.; Ranney, J.; Reed, R.M.; Ryan, P.F.; Schweitzer, M.; Smith, D.; Thomason, P.; Wade, M.C.

    1999-07-01

    In 1994, Oak Ridge National Laboratory (ORNL) was tasked by the National Park Service (NPS) to prepare an Environmental Report (ER) for Section 8B of the Foothills Parkway in the Great Smoky Mountains National Park (GSMNP). Section 8B represents 27.7 km (14.2 miles) of a total of 115 km (72 miles) of the planned Foothills Parkway and would connect the Cosby community on the east to the incorporated town of Pittman Center to the west. The major deliverables for the project are listed. From August 1995 through October 1996, NPS, GSMNP, and ORNL staff interacted with Federal Highway Administration staff to develop a conceptual design plan for Section 8B with the intent of protecting critical resources identified during the ER process to the extent possible. In addition, ORNL arranged for bioengineering experts to discuss techniques that might be employed on Section 8B with NPS, GSMNP, and ORNL staff during September 1996. For the purposes of this ER, there are two basic alternatives under consideration: (1) a build alternative and (2) a no-build alternative. Within the build alternative are a number of options including constructing Section 8B with no interchanges, constructing Section 8B with an interchange at SR416 or U.S. 321, constructing Section 8B with a spur road on Webb Mountain, and considering operation of Section 8B both before and after the operation of Section 8C. The no-build alternative is considered the no-action alternative and is not to construct Section 8B. This volume of the ER inventories the fishes and benthic macroinvertebrates inhabiting the aquatic ecosystems potentially affected by the proposed construction of Section 8B. Stream biological surveys were completed at 31 stream sites during the Fall of 1994. The sampling strategy for both invertebrates and fish was to survey the different taxa from all available habitats. For benthic invertebrates, a standardized qualitative manual collection technique was employed for all 31 stations. For fish

  5. Foothills Parkway Section 8B Final Environmental Report, Volume 5, Appendices J-M

    Blasing, T.J.; Cada, G.F.; Carer, M.; Chin, S.M.; Dickerman, J.A.; Etnier, D.A.; Gibson, R.; Harvey, M.; Hatcher, B.; Lietzske, D.; Mann, L.K.; Mulholland, P.J.; Petrich, C.H.; Pounds, L.; Ranney, J.; Reed, R.M.; Ryan, P.F.; Schweitzer, M.; Smith, D.; Thomason, P.; Wade, M.C.

    1999-07-01

    In 1994, Oak Ridge National Laboratory (ORNL) was tasked by the National Park Service (NPS) to prepare an Environmental Report (ER) for Section 8B of the Foothills Parkway in the Great Smoky Mountains National Park (GSMNP). Section 8B represents 27.7 km (14.2 miles) of a total of 115 km (72 miles) of the planned Foothills Parkway and would connect the Cosby community on the east to the incorporated town of Pittman Center to the west. The major deliverables for the project are listed. From August 1995 through October 1996, NPS, GSMNP, and ORNL staff interacted with Federal Highway Administration staff to develop a conceptual design plan for Section 8B with the intent of protecting critical resources identified during the ER process to the extent possible. In addition, ORNL arranged for bioengineering experts to discuss techniques that might be employed on Section 8B with NPS, GSMNP, and ORNL staff during September 1996. For the purposes of this ER, there are two basic alternatives under consideration: (1) a build alternative and (2) a no-build alternative. Within the build alternative are a number of options including constructing Section 8B with no interchanges, constructing Section 8B with an interchange at SR 416 or U.S. 321, constructing Section 8B with a spur road on Webb Mountain, and considering operation of Section 8B both before and after the operation of Section 8C. The no-build alternative is considered the no-action alternative and is not to construct Section 8B. This volume of the ER consists of Appendices J through M, which describe potential impacts regarding traffic, noise, and aesthetics. The results of the traffic studies described in these appendices resulted in the following conclusions: Unacceptable levels of service will occur on numerous roads within and outside of the park increasingly in the Mure based upon current and future regional growth. However, the results of the traffic assessment indicated that there would be no significant or

  6. Ab initio many-body calculation of the 7Be(p,gamma)8B radiative capture

    Navratil, Petr; Quaglioni, Sofia

    2011-01-01

    We apply the ab initio no-core shell model/resonating group method (NCSM/RGM) approach to calculate the cross section of the 7Be(p,gamma)8B radiative capture. This reaction is important for understanding the solar neutrino flux. Starting from a selected similarity-transformed chiral nucleon-nucleon interaction that accurately describes two-nucleon data, we performed parameter-free many-body calculations that simultaneously predict both the normalization and the shape of the S-factor. We study the dependence on the number of 7Be eigenstates included in the coupled-channel equations and on the size of the harmonic oscillator basis used for the expansion of the eigenstates and of the localized parts of the integration kernels. Our S-factor result at zero energy is on the lower side of, but consistent with, the latest evaluation.

  7. Temporal associations of life with solar and geophysical activity

    T. K. Breus

    Full Text Available In biology, circadian rhythms with a period of one cycle in 20–28 h are known to be ubiquitous and partly endogenous. Rhythms with a frequency lower than one cycle per day are called 'infradian rhythms'. Among them are components with one cycle in about 3.5, 7, 14 and 28 days, the multiseptans, which, like the circadians, must be regarded as a general characteristic of life: they characterize unicells as well as much more differentiated organisms. We hypothesize that heliogeophysical factors other than the solar visible light, held responsible for the evolution of circadian periodicity, underlie the infradian rhythms of biosystems. The periodicities in the solar wind and variations in the interplanetary magnetic field (IMF which are associated with the solar rotation are very similar in length to the biological periodicities. We investigate the temporal relations of variations in solar activity and in biological systems to test associations between events in the IMF, in geomagnetic disturbance, in myocardial infarction and in physiology. By cross-spectral analysis, we also find relations at certain frequencies between changes in human physiology on the one hand, and (1 the vertical component of the induction vector of the IMF, Bz, and (2 a global index of geomagnetic disturbance, Kp, on the other hand. We wish to stimulate interest in these periodicities of both biological systems and geophysical endpoints among physicists and biologists alike, so that problems relevant to clinicians and other biologists, including evolutionists, are eventually solved by their cooperation with the geophysical community.

  8. Solar activity around AD 775 from aurorae and radiocarbon

    Neuhäuser, R.; Neuhäuser, D. L.

    2015-04-01

    A large variation in 14C around AD 775 has been considered to be caused by one or more solar super-flares within one year. We critically review all known aurora reports from Europe as well as the Near, Middle, and Far East from AD 731 to 825 and find 39 likely true aurorae plus four more potential aurorae and 24 other reports about halos, meteors, thunderstorms etc., which were previously misinterpreted as aurorae or misdated; we assign probabilities for all events according to five aurora criteria. We find very likely true aurorae in AD 743, 745, 762, 765, 772, 773, 793, 796, 807, and 817. There were two aurorae in the early 770s observed near Amida (now Diyarbak\\i r in Turkey near the Turkish-Syrian border), which were not only red, but also green-yellow - being at a relatively low geomagnetic latitude, they indicate a relatively strong solar storm. However, it cannot be argued that those aurorae (geomagnetic latitude 43 to 50°, considering five different reconstructions of the geomagnetic pole) could be connected to one or more solar super-flares causing the 14C increase around AD 775: There are several reports about low- to mid-latitude aurorae at 32 to 44° geomagnetic latitude in China and Iraq; some of them were likely observed (quasi-)simultaneously in two of three areas (Europe, Byzantium/Arabia, East Asia), one lasted several nights, and some indicate a particularly strong geomagnetic storm (red colour and dynamics), namely in AD 745, 762, 793, 807, and 817 - always without 14C peaks. We use 39 likely true aurorae as well as historic reports about sunspots together with the radiocarbon content from tree rings to reconstruct the solar activity: From AD {˜ 733} to {˜ 823}, we see at least nine Schwabe cycles; instead of one of those cycles, there could be two short, weak cycles - reflecting the rapid increase to a high 14C level since AD 775, which lies at the end of a strong cycle. In order to show the end of the dearth of naked-eye sunspots, we

  9. Large active retrodirective arrays for solar power satellites

    Chernoff, R.

    1978-01-01

    An active retrodirective array (ARA) transmits a beam toward the apparent source of an illuminating signal called the pilot. The array produces the RF power. Retrodirectivity is achieved by retransmitting from each element of the array a signal whose phase is the 'conjugate' of that received by the element. Application of the ARA to the solar power satellite concept has been proposed. A method of providing a reference phase is described, called 'central phasing', which eliminates the need for a rigid structure ordinarily needed in order to realize accurate retrodirectivity.

  10. Time-integrated energy budget of a solar activity complex

    The authors examine the sunspot and facular contributions to luminosity fluctuations due to a solar activity complex over its lifetime from June to November 1982. Both direct, photometric observations of irradiance fluctuations and modelled 'proxy' fluctuations based on published sunspot and calcium plage areas are used. The total facular energy excess is found to be between 70 and 120% of the sunspot deficit of approx. 1037 erg. Thus. at a minimum, a major portion of the missing sunspot flux is radiated by faculae, and energy balance or even an excess is possible. (author)

  11. Sign singularity and flares in solar active region NOAA 11158

    Sorriso-Valvo, Luca; Kazachenko, Maria D; Krucker, Sam; Primavera, Leonardo; Servidio, Sergio; Vecchio, Antonio; Welsch, Brian T; Fisher, George H; Lepreti, Fabio; Carbone, Vincenzo

    2015-01-01

    Solar Active Region NOAA 11158 has hosted a number of strong flares, including one X2.2 event. The complexity of current density and current helicity are studied through cancellation analysis of their sign-singular measure, which features power-law scaling. Spectral analysis is also performed, revealing the presence of two separate scaling ranges with different spectral index. The time evolution of parameters is discussed. Sudden changes of the cancellation exponents at the time of large flares, and the presence of correlation with EUV and X-ray flux, suggest that eruption of large flares can be linked to the small scale properties of the current structures.

  12. Evolution and Dynamics of a Solar Active Prominence

    Magara, Tetsuya

    2015-01-01

    The life of a solar active prominence, one of the most remarkable objects on the Sun, is full of dynamics; after first appearing on the Sun the prominence continuously evolves with various internal motions and eventually produces a global eruption toward the interplane- tary space. Here we report that the whole life of an active prominence is successfully re- produced by performing as long-term a magnetohydrodynamic simulation of a magnetized prominence plasma as was ever done. The simulation reveals underlying dynamic processes that give rise to observed properties of an active prominence: invisible subsurface flows self- consistently produce the cancellation of magnetic flux observed at the photosphere, while observed and somewhat counterintuitive strong upflows are driven against gravity by en- hanced gas pressure gradient force along a magnetic field line locally standing vertical. The most highlighted dynamic event, transition into an eruptive phase, occurs as a natural con- sequence of the self-consiste...

  13. A 300-Year Typhoon Record in Taiwan and the Relationship with Solar Activity

    Chih-wen Hung

    2013-01-01

    Previous studies have identified possible linkages between solar activity and tropical cyclone activity in the United States and Caribbean. This study used historical typhoon records dating back to the early 1700s, the Central Weather Bureau records (since 1897), and the JTWC (Joint Typhoon Warning Center) (since 1945) to investigate the relationship between solar activity and the number of typhoons in Taiwan. The results show that a negative relationship exists between solar activity and typ...

  14. Eruptions that Drive Coronal Jets in a Solar Active Region

    Sterling, Alphonse C.; Moore, Ronald L.; Falconer, David A.; Panesar, Navdeep K.; Akiyama, Sachiko; Yashiro, Seiji; Gopalswamy, Nat

    2016-01-01

    Solar coronal jets are common in both coronal holes and in active regions (e.g., Shibata et al. 1992, Shimojo et al. 1996, Cirtain et al. 2007. Savcheva et al. 2007). Recently, Sterling et al. (2015), using data from Hinode/XRT and SDO/AIA, found that coronal jets originating in polar coronal holes result from the eruption of small-scale filaments (minifilaments). The jet bright point (JBP) seen in X-rays and hotter EUV channels off to one side of the base of the jet's spire develops at the location where the minifilament erupts, consistent with the JBPs being miniature versions of typical solar flares that occur in the wake of large-scale filament eruptions. Here we consider whether active region coronal jets also result from the same minifilament-eruption mechanism, or whether they instead result from a different mechanism (e.g. Yokoyama & Shibata 1995). We present observations of an on-disk active region (NOAA AR 11513) that produced numerous jets on 2012 June 30, using data from SDO/AIA and HMI, and from GOES/SXI. We find that several of these active region jets also originate with eruptions of miniature filaments (size scale 20'') emanating from small-scale magnetic neutral lines of the region. This demonstrates that active region coronal jets are indeed frequently driven by minifilament eruptions. Other jets from the active region were also consistent with their drivers being minifilament eruptions, but we could not confirm this because the onsets of those jets were hidden from our view. This work was supported by funding from NASA/LWS, NASA/HGI, and Hinode. A full report of this study appears in Sterling et al. (2016).

  15. Foothills Parkway Section 8B Final Environmental Report, Volume 4, Appendices E-I

    Blasing, T.J.; Cada, G.F.; Carer, M.; Chin, S.M.; Dickerman, J.A.; Etnier, D.A.; Gibson, R.; Harvey, M.; Hatcher, B.; Lietzske, D.; Mann, L.K.; Mulholland, P.J.; Petrich, C.H.; Pounds, L.; Ranney, J.; Reed, R.M.; Ryan, P.F.; Schweitzer, M.; Smith, D.; Thomason, P.; Wade, M.C.

    1999-07-01

    In 1994, Oak Ridge National Laboratory (ORNL) was tasked by the National Park Service (NPS) to prepare an Environmental Report (ER) for Section 8B of the Foothills Parkway in the Great Smoky Mountains National Park (GSMNP). Section 8B represents 27.7 km (14.2 miles) of a total of 115 km (72 miles) of the planned Foothills Parkway and would connect the Cosby community on the east to the incorporated town of Pittman Center to the west. The major deliverables for the project are listed. From August 1995 through October 1996, NPS, GSMNP, and ORNL staff interacted with Federal Highway Administration staff to develop a conceptual design plan for Section 8B with the intent of protecting critical, resources identified during the ER process to the extent possible. In addition, ORNL arranged for bioengineering experts to discuss techniques that might be employed on Section 8B with NPS, GSMNP, and ORNL staff during September 1996. For the purposes of this ER, there are two basic alternatives under consideration: (1) a build alternative and (2) a no-build alternative. Within the build alternative are a number of options including constructing Section 8B with no interchanges, constructing Section 8B with an interchange at SR 416 or U.S. 321, constructing Section 8B with a spur road on Webb Mountain, and considering operation of Section 8B both before and after the operation of Section 8C. The no-build alternative is considered the no-action alternative and is not to construct Section 8B. This volume of the ER consists of Appendices E through I (all ecological survey reports), which are summarized individually in the sections that follow. The following conclusions result from the completion of these surveys and the ER impact analysis: (1) Forest clearing should be limited as much as possible; (2) Disturbed areas should be replanted with native trees; (3) Drainages should be bridged rather than leveled with cut and fill; (4) For areas of steep slopes and potential erosion

  16. Variations of the temperature and solar activity in China

    MingQi Li; QuanSheng Ge; ZhiXin Hao; JingYun Zheng

    2014-01-01

    In this paper we analyze daily mean, minimum, and maximum temperature data collected at 119 meteorological stations over five regions of China during the period 1951-2010. The series of minimum, maximum, and mean temperatures from each climatic region have similar signatures, but there are differences among the five regions and the countrywide average. The results indicate that the periods of faster warming were not synchronous across the regions studied: warming in northeast China and Tibet began in 1986, while in central-east, southeast, and northwest China the warming emerged in 1995. Furthermore, central-east and northwest China, and Tibet, have warmed continuously since 2000, but the temper-ature has decreased during this period in southeast China. We evaluated the evolution of these temperature series using a novel nonlinear filtering technique based on the concept of the lifetime of temperature curves. The decadal to secular evolution of solar activity and temperature variation had similar signatures in the northeast, southeast, and northwest re-gions and the average across the whole country, indicating that solar activity is a significant control on climate change over secular time scales in these regions. In comparison with these regions, the signatures were different in central-east China and Tibet because of regional differences (e.g., landforms and elevation) and indirect effects (e.g., cloud cover influencing the radiation balance, thereby inducing climate change). Furthermore, the results of wavelet analysis indicated that the El Niño Southern Oscillation (ENSO) has had a significant impact on climate change, but at different times among the regions, and these changes were most probably induced by differing responses of the atmospheric system to solar forcing.

  17. On the solar activity variations of nocturnal F region vertical drifts covering two solar cycles in the Indian longitude sector

    Madhav Haridas, M. K.; Manju, G.; Pant, Tarun Kumar

    2015-02-01

    A comprehensive analysis of the seasonal and solar cycle variabilities of nighttime vertical drift over the Indian longitude sector is accomplished using ionosonde data located at the magnetic equatorial location, Trivandrum (8.5°N, 76.5°E). The analysis extends over a span of two decades (1988-2008). The representative seasonal variations based on the extensive data of nocturnal vertical drift during three different solar activity epochs is arrived at, for the first time. Seasonally, it is seen that maximum post sunset Vd is obtained in vernal equinox (VE), followed by autumnal equinox (AE), winter solstice (WS), and summer solstice (SS) for high and moderate solar epochs, while for low solar epoch, maximum Vd occurs in WS followed by VE, AE, and SS. Further, the role of sunset times at the magnetic conjugate points in modulating the time and magnitude of peak drifts during different solar epochs is ascertained. The equinoctial asymmetry in peak Vd during high and moderate solar epochs is another significant outcome of this study. The solar activity dependence of vertical drift for a wide range of solar fluxes has been quantified for all the seasons. In the present era of GPS-based communication and navigation, these are important results that give a better handle in understanding essential factors that impact equatorial ionospheric phenomena.

  18. Reaction mechanisms in collisions induced by 8B beam close to the barrier

    The aim of the proposed experiment is to investigate on the reaction dynamics of proton-halo induced collisions at energies around the Coulomb barrier where coupling to continuum effects are expected to be important. We propose to measure $^{8}$B+$^{64}$Zn elastic scattering angular distribution together with the measurement, for the first time, of p-$^{7}$Be coincidences coming from transfer and/or break-up of $^{8}$B. The latter will allow a better understanding of the relative contribution of elastic $\\textit{vs}$ non-elastic break-up in reactions induced by extremely weakly-bound nuclei. We believe that with the availability of the post accelerated $^{8}$B beam at REX-ISOLDE we will be able to collect for the first time high quality data for the study of such an important topic.

  19. Solar Energy Education. Social studies: activities and teacher's guide. Field test edition

    1982-01-01

    Solar energy information is made available to students through classroom instruction by way of the Solar Energy Education teaching manuals. In this manual solar energy, as well as other energy sources like wind power, is introduced by performing school activities in the area of social studies. A glossary of energy related terms is included. (BCS)

  20. Possible Relationship of the Solar Activity and Earthquakes

    Gonzalez-Trejo, J. I.; Cervantes, F.; Real-Ramírez, C. A.; Hoyos-Reyes, L. F.; Miranda-Tello, R.; Area de Sistemas Computacionales

    2013-05-01

    Several authors have recently argued that there is a relationship between solar activity and big earthquakes. This work compares Dst index fluctuations along 2012 and 2013, with the earthquake activity near La Paz, Baja California, Mexico. The earthquakes measurements at this place were divided according its deep focus. It was observed that the frequency of the deeper earthquakes increases shortly after considerable fluctuations in the Dst index are registered. We assume that the number of deep earthquakes increases because the interaction of the tectonic plate below that place and the tectonic plates in contact with it increases. This work also shows that the frequency of shallowest minor and light earthquakes increases shortly before a strongest earthquake takes place in the vicinity.

  1. Lower limit of intensity for the solar activity in microwaves

    The active region McMath 10433 has produced various flares and burts in radio frequency in the beginning of july 1974. This region was scanned countinously in 22.2 GHz with a radio telescope showing a 4 min. arc beam, in various periods of the month. In comparison with the results simultaneously obtained with a normal solar radio telescope, in 7 GHz, it was verified that there is an important explosive activity in lower levels in the limit of detection of an usual patrolling instrument. The morphology of these events, in its progress in the time, is similar to that normaly known, and allowed, the re-interpretation of simple events. A completly new type of event was defined: the fast absorptions. The correlation of events in microwaves with 'SPA' recorded in 'VLF' propagation is also discussed

  2. 7Be- and 8B-reaction dynamics at Coulomb barrier energies

    Mazzocco, M.; Boiano, A.; Boiano, C.; La Commara, M.; Manea, C.; Parascandolo, C.; Pierroutsakou, D.; Signorini, C.; Strano, E.; Torresi, D.; Yamaguchi, H.; Kahl, D.; Acosta, L.; Di Meo, P.; Fernandez-Garcia, J. P.; Glodariu, T.; Grebosz, J.; Guglielmetti, A.; Imai, N.; Hirayama, Y.; Ishiyama, H.; Iwasa, N.; Jeong, S. C.; Jia, H. M.; Keeley, N.; Kim, Y. H.; Kimura, S.; Kubono, S.; Lay, J. A.; Lin, C. J.; Marquinez-Duran, G.; Martel, I.; Miyatake, H.; Mukai, M.; Nakao, T.; Nicoletto, M.; Pakou, A.; Rusek, K.; Sakaguchi, Y.; Sánchez-Benítez, A. M.; Sava, T.; Sgouros, O.; Stefanini, C.; Soramel, F.; Soukeras, V.; Stiliaris, E.; Stroe, L.; Teranishi, T.; Toniolo, N.; Wakabayashi, Y.; Watanabe, Y. X.; Yang, L.; Yang, Y. Y.

    2016-05-01

    We investigated the reaction dynamics induced by the Radioactive Ion Beams 7Be and 8B on a 208Pb target at energies around the Coulomb barrier. The two measurements are strongly interconnected, being 7Be (Sα = 1.586 MeV) the loosely bound core of the even more exotic 8B (Sp = 0.1375 MeV) nucleus. Here we summarize the present status of the data analysis for the measurement of the elastic scattering process for both reactions and the preliminary results for the optical model analysis of the collected data.

  3. 7Be- and 8B-reaction dynamics at Coulomb barrier energies

    Mazzocco M.

    2016-01-01

    Full Text Available We investigated the reaction dynamics induced by the Radioactive Ion Beams 7Be and 8B on a 208Pb target at energies around the Coulomb barrier. The two measurements are strongly interconnected, being 7Be (Sα = 1.586 MeV the loosely bound core of the even more exotic 8B (Sp = 0.1375 MeV nucleus. Here we summarize the present status of the data analysis for the measurement of the elastic scattering process for both reactions and the preliminary results for the optical model analysis of the collected data.

  4. Spring-fall asymmetry of substorm strength, geomagnetic activity and solar wind: Implications for semiannual variation and solar hemispheric asymmetry

    Marsula, K.; Tanskanen, E.; Love, J.J.

    2011-01-01

    We study the seasonal variation of substorms, geomagnetic activity and their solar wind drivers in 1993–2008. The number of substorms and substorm mean duration depict an annual variation with maxima in Winter and Summer, respectively, reflecting the annual change of the local ionosphere. In contradiction, substorm mean amplitude, substorm total efficiency and global geomagnetic activity show a dominant annual variation, with equinoctial maxima alternating between Spring in solar cycle 22 and Fall in cycle 23. The largest annual variations were found in 1994 and 2003, in the declining phase of the two cycles when high-speed streams dominate the solar wind. A similar, large annual variation is found in the solar wind driver of substorms and geomagnetic activity, which implies that the annual variation of substorm strength, substorm efficiency and geomagnetic activity is not due to ionospheric conditions but to a hemispherically asymmetric distribution of solar wind which varies from one cycle to another. Our results imply that the overall semiannual variation in global geomagnetic activity has been seriously overestimated, and is largely an artifact of the dominant annual variation with maxima alternating between Spring and Fall. The results also suggest an intimate connection between the asymmetry of solar magnetic fields and some of the largest geomagnetic disturbances, offering interesting new pathways for forecasting disturbances with a longer lead time to the future.

  5. Solar and terrestrial physics. [effects of solar activities on earth environment

    1975-01-01

    The effects of solar radiation on the near space and biomental earth, the upper atmosphere, and the magnetosphere are discussed. Data obtained from the OSO satellites pertaining to the solar cycle variation of extreme ultraviolet (EUV) radiation are analyzed. The effects of solar cycle variation of the characteristics of the solar wind are examined. The fluid mechanics of shock waves and the specific relationship to the characteristics of solar shock waves are investigated. The solar and corpuscular heating of the upper atmosphere is reported based on the findings of the AEROS and NATE experiments. Seasonal variations of the upper atmosphere composition are plotted based on OGO-6 mass spectrometer data.

  6. Active Solar Sail Designs for Chip-Scale Spacecraft

    Weis, Lorraine; Peck, Mason

    2014-01-01

    Centimeter-scale spacecraft, known as ”Chipsats,” have very high surface-area-to-mass ratios, which accentuates solar radiation pressure (SRP) effects. In contrast to traditional. large solar sails, chip-scale solar sails have the potential to be highly agile in terms of attitude because of their structural rigidity and low moments of inertia. This ability to easily reorient a solar sail greatly expands the orbits that a solar-sail spacecraft can achieve. Solar sail actuation through electroc...

  7. On the Relation between Solar Activity and Clear-Sky Terrestrial Irradiance

    Feulner, Georg

    2012-01-01

    The Mauna Loa Observatory record of direct-beam solar irradiance measurements for the years 1958-2010 is analysed to investigate the variation of clear-sky terrestrial insolation with solar activity over more than four solar cycles. The raw irradiance data exhibit a marked seasonal cycle, extended periods of lower irradiance due to emissions of volcanic aerosols, and a long-term decrease in atmospheric transmission independent of solar activity. After correcting for these effects, it is found that clear-sky terrestrial irradiance typically varies by about 0.2 +/- 0.1% over the course of the solar cycle, a change of the same order of magnitude as the variations of the total solar irradiance above the atmosphere. An investigation of changes in the clear-sky atmospheric transmission fails to find a significant trend with sunspot number. Hence there is no evidence for a yet unknown effect amplifying variations of clear-sky irradiance with solar activity.

  8. Energy balance in solar active regions - The dip of April, 1985

    Hudson, H. S.

    1986-01-01

    The presence of a solar active region affects the luminosity of the sun. Sunspots directly produce 'dips' in the total solar irradiance approximately proportionally to their projected area, while faculae produce excess energy. These effects were discovered during the solar maximum period of 1980, and the sunspot effect during solar minimum is examined. The 'dip' due to an active region in April, 1985, as observed in the total solar irradiance by the ACRIM instrument on the Solar Maximum Mission is examined. These data (obtained after the spacecraft repair in May, 1984) have simple variations, relative to those observed in 1980, because of the reduced level of activity approaching solar minimum. It is found that the PSI index of projected sunspot area as defined in 1980 appears to describe this 'dip' satisfactorily.

  9. Periodic Variation of the North-South Asymmetry of Solar Activity Phenomena

    V. Κ. Verma

    2000-09-01

    We report here a study of various solar activity phenomena occurring in both north and south hemispheres of the Sun during solar cycles 8-23. In the study we have used sunspot data for the period 1832—1976, flare index data for the period 1936-1993, H flare data 1993-1998 and solar active prominences data for the period 1957-1998. Earlier Verma reported long-term cyclic period in N-S asymmetry and also that the N-S asymmetry of solar activity phenomena during solar cycles 21, 22, 23 and 24 will be south dominated and the N-S asymmetry will shift to north hemisphere in solar cycle 25. The present study shows that the N-S asymmetry during solar cycles 22 and 23 are southern dominated as suggested by Verma.

  10. Activity Analyses for Solar-Type Stars Observed With Kepler. I. Proxies of Magnetic Activity

    He, Han; Yun, Duo

    2016-01-01

    Light curves of solar-type stars often show gradual fluctuations due to rotational modulation by magnetic features (starspots and faculae) on stellar surfaces. Two quantitative measures of modulated light curves are employed as the proxies of magnetic activity for solar-type stars observed with Kepler telescope. The first is named autocorrelation index $i_{AC}$, which describes the degree of periodicity of the light curve, the second is the effective fluctuation range of the light curve $R_{eff}$, which reflects the depth of rotational modulation. The two measures are complementary and depict different aspects of magnetic activities on solar-type stars. By using the two proxies $i_{AC}$ and $R_{eff}$, we analyzed activity properties of two carefully selected solar-type stars observed with Kepler (Kepler ID: 9766237 and 10864581), which have distinct rotational periods (14.7 vs. 6.0 days). We also applied the two measures to the Sun for a comparative study. The result shows that both the measures can reveal cy...