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1. Microwave Diagnostics of Dynamic Processes and Oscillations in Groups of Solar Coronal Magnetic Loops

Author: S. Urpo, Maxim L. Khodachenko, Helmut O. Rucker, A. G. Kislyakov, and V. V. Zaitsev
Subjects: Physics, Astron, Solar flare, Space and Planetary Science, Equivalent circuit, Astronomy and Astrophysics, Coronal loop, Astrophysics, Electron, Electric current, Microwave, Magnetic field
Abstract: Low-frequency (LF) modulations of the solar microwave radiation (37 GHz) recorded at the Metsahovi Radio Observatory, are analyzed. Since the intensity of solar microwave radiation, produced by the electron gyrosynchrotron mechanism, is dependent on a value of the background magnetic field [Dulk, G. A.: 1985, Ann. Rev. Astron. Astrophys. 23, 169–224], slow variations of the magnetic field associated with disturbances of the electric current in a radiating source, can modulate the intensity of the microwave radiation. The observed multi-track features of the LF spectra are interpreted as a signature of a complex multi-loop structure of the radiating source. Application of the equivalent electric circuit models of interacting loops allows to explain and reproduce the main dynamical features of the observed LF modulation dynamic spectra.
Published: 2006
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2. On the Possible Connection between Photospheric 5-Min Oscillation and Solar Flare Microwave Emission

Author: A. V. Stepanov, S. Urpo, V. V. Zaitsev, and A. G. Kislyakov
Subjects: Physics, Sunspot, Photosphere, Solar flare, Oscillation, Astrophysics::High Energy Astrophysical Phenomena, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Spectral line, Intensity (physics), Radio telescope, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, Microwave
Abstract: Dynamic spectra of low-frequency modulation of microwave emission from solar flares are obtained. Data of 15 bursts observed in 1989-2000 with Metsahovi radio telescope at 37 GHz have been used. During 13 bursts a 5-min modulation of the microwave emission intensity was detected with the frequency of νI = 3.2 ± 0.24 (1σ ) mHz. Five bursts revealed a 5-min wave superimposed on a ∼1 Hz, linear frequency modulated signal generated, presumably, by coronal magnetic loop, this wave frequency is νfm = 3.38 ± 0.37 (1σ ) mHz. Both intensity and frequency modulations detected are in good agreement with the data on 5-min global oscillations of photosphere and with the data on the umbral velocity oscillations observed in the vicinity of sunspots. Possible role of p-mode photospheric oscillations in modulation of microwave burst emission is discussed.
Published: 2006
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3. Low-frequency modulations in the solar microwave radiation as a possible indicator of inductive interaction of coronal magnetic loops

Author: Maxim L. Khodachenko, Helmut O. Rucker, A. G. Kislyakov, S. Urpo, and V. V. Zaitsev
Subjects: Physics, Solar flare, Space and Planetary Science, Astronomy and Astrophysics, Coronal loop, Astrophysics, Plasma, Low frequency, Capacitance, Microwave, Magnetic field, Electronic circuit
Abstract: Low-frequency (LF) modulations of 37 GHz microwave radiation during solar flares, recorded at the Metsahovi Radio Observatory, are considered. A fast Fourier transformation with a sliding window is used to obtain the dynamic spectra of the LF pulsations. We pay attention to the LF dynamic spectra having a specific multi-track structure, which is supposed to be an indication of a complex multi-loop composition of a flaring region. Application of the equivalent electric circuit models of the loops including the effects of electromagnetic inductive interaction in groups of slowly growing current-carrying magnetic loops allows us to explain and reproduce the main dynamical features of the observed LF modulation dynamic spectra. Each loop is considered as an equivalent electric circuit with variable parameters (resistance, capacitance and inductive coefficients) which depend on shape, scale, position of the loop with respect to other loops, as well as on the plasma parameters and value of the total longitudinal current in the magnetic tube.
Published: 2005
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4. Manifestations of the 5-Min Photospheric Oscillations in the Solar Microwave Emission

Author: A. G. Kislyakov, V. V. Zaitsev, and S. Urpo
Subjects: Physics, Quantum optics, Nuclear and High Energy Physics, Solar flare, Oscillation, Astrophysics::High Energy Astrophysical Phenomena, Astronomy, Astronomy and Astrophysics, Statistical and Nonlinear Physics, Astrophysics::Cosmology and Extragalactic Astrophysics, Emission intensity, Spectral line, Electronic, Optical and Magnetic Materials, Observatory, Modulation, Astrophysics::Solar and Stellar Astrophysics, Electrical and Electronic Engineering, Frequency modulation
Abstract: Dynamic spectra of low-frequency (LF) modulation of microwave emission during solar flares are obtained. Observation data for five radio bursts at frequency 37 GHz recorded by a 14-m Metsaahovi observatory (Finland) radiotelescope in the period from 1990 to 1993 were used. Frequency modulation of the radio emission intensity with the average period 296±37 (1σ) s, which is close to the period of well-known photospheric oscillations, was observed. Possible mechanisms of photospheric oscillation influence on the regions of radio burst generation are discussed.
Published: 2003
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5. Spectral-temporal evolution of low-frequency pulsations in the microwave radiation of solar flares

Author: S. Urpo, Alexander V. Stepanov, A. G. Kislyakov, E. I. Shkelev, and V. V. Zaitsev
Subjects: Physics, Solar flare, Negative frequency, business.industry, Frequency drift, Astronomy and Astrophysics, Plasma, Low frequency, Computational physics, law.invention, Optics, Space and Planetary Science, law, Plasma parameter, business, Microwave, Flare
Abstract: Low-frequency pulsations of 22 and 37 GHz microwave radiation detected during solar flares are analyzed. Several microwave bursts observed at the Metsahovi Radio Observatory are studied with time resolutions of 100 and 50 ms. A fast Fourier transformation with a sliding window and the Wigner-Ville method are used to obtain frequency-time diagrams for the low-frequency pulsations, which are interpreted as natural oscillations of coronal magnetic loops; the dynamical spectra of the pulsations are synthesized for the first time. Three types of low-frequency fluctuations modulating the flare microwave radiation can be distinguished in the observations. First, there are fast and slow magneto-acoustic oscillations with periods of 0.5–0.8 s and 200–280 s, respectively. The fast magneto-acoustic oscillations appear as trains of narrow-band signals with durations of 100–200 s, a positive frequency drift dν/dt=0.25 MHz/min, and frequency splitting δν=0.01–0.05 Hz. Second, there are natural oscillations of the coronal magnetic loops as equivalent electrical circuits. These oscillations have periods of 0.5–10 s and positive or negative frequency drift rates dν/dt=8×10−3 Hz/min or dν/dt=−1.3×10−2 Hz/min, depending on the phase of the radio outburst. Third, there are modulations of the microwave radiation by short periodic pulses with a period of 20 s. The dynamical spectra of the low-frequency pulsations supply important information about the parameters of the magnetic loops: the ratio of the loop radius to its length r/L≈0.1, the plasma parameter β≈10−3, the ratio of the plasma densities outside and inside the loop ρe/ρi≈10−2, and the electrical current flowing along the loop I≈1012 A.
Published: 2003
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6. 147 GHz VLBI observations: Detection of 3C 273 and 3C 279 on the 3100 km baseline Metsähovi – Pico Veleta

Author: Thomas P. Krichbaum, S. Urpo, S. Navarro, D. A. Graham, P. Könönen, J. A. Zensus, K. Wiik, Albert Greve, J. Peltonen, John Conway, Michael Grewing, P. Sjöman, Roy Booth, Ari Mujunen, Jouko Ritakari, M. Berton, F. Rantakyro, D. John, and E. Oinaskallio
Subjects: Physics, Space and Planetary Science, Baseline (sea), Brightness temperature, Very-long-baseline interferometry, Flux, Astronomy, Astronomy and Astrophysics, Astrophysics, Lower limit
Abstract: We report a successful VLBI observation at 147 GHz (2.1 mm) on the 3 100 km long baseline between the telescopes at Metsahovi (Finland) and Pico Veleta (Spain). The sources 3C 273B and 3C 279 were detected with a SNR of∼10. For these sources we estimate that 25-30% of the total flux is detectable as correlated flux on the 3 100 km baseline, which gives at 147 GHz a lower limit of the brightness temperature of the inner VLBI jet region of ∼1×10 1 0 K.
Published: 2002
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7. Search for new flat-spectrum radio sources

Author: S. Wiren, Mauri Valtonen, Harri Teräsranta, and S. Urpo
Subjects: Physics, Radio telescope, X-shaped radio galaxy, Space and Planetary Science, Duty cycle, Extrapolation, Astronomy, Astronomy and Astrophysics, Source counts, Astrophysics, Galactic plane, Declination
Abstract: GHz continuum observations with the Metsahovi Radio telescope are used to identifying new flat spectrum radio sources selected from lower frequency survey data. The sample is complete to sources with a flux higher than 0.5 Jy at 1.4 GHz, 0:5 between 1.4 and 4.85 GHz, declination from 0 to +75 degrees and sources more than 20 from the galactic plane. Additional strong sources from the 5 GHz survey were observed to get the sample as complete as possible down to 1.0 Jy at 22 GHz for extrapolation of source counts to lower flux levels. The new flat spectrum sources will be added to our monitoring sample and their duty cycle will be studied for the coming -ray observatiories AGILE and GLAST.
Published: 2001
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8. Millimeter-radio, SOHO/EIT 171 Å features and the polar faculae in the polar zones of the Sun

Author: S. Urpo, V. I. Makarov, Esko Valtaoja, Andrey Tlatov, L. V. Makarova, and A. Riehokainen
Subjects: Physics, Astronomy, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Latitude, Radio telescope, Magnetic loop, Space and Planetary Science, White light, Astrophysics::Solar and Stellar Astrophysics, Polar, Millimeter, Astrophysics::Earth and Planetary Astrophysics
Abstract: In this work we study different manifestations of activity in the polar zones of the Sun in order to gain understanding on the phenomenon of enhanced radio temperature regions (ETR) at high solar latitudes. We have obtained simultaneous radio and optical data during 9 days in 1997. The radio data from the Metsahovi radio telescope, Finland, consisted of 37 GHz and 87 GHz solar maps. White light observations at the Kislovodsk solar mountain station in Russia were used to measure the coordinates of polar faculae groups and diffuse bright structures. We also compared our data with the 171 AEUV SOHO/EIT images for the same time periods. We find the ETRs in general coincide with the relatively dark areas seen in the SOHO/EIT images. Bright structures in the SOHO/EIT maps are, in general, encircled by the polar faculae groups and diffuse bright structures visible in white light. Some of the EUV bright structures appear to be bases of solar plumes. Connections between ETRs and polar faculae are complicated; sometimes polar faculae groups and diffuse bright structures are situated around the ETR maxima or at their borders, sometimes we see the polar faculae groups distributed over the whole ETR area. Some faint ETRs appear to have no associated polar faculae. However, in general there is a correlation between the ETRs, the polar faculae groups, and the bright structures (bases of the plumes and some other features), indicating that they are different manifestations of the same underlying activity. It is possible that magnetic loops in the active areas, traced by the polar faculae, are responsible for the observed radio enhancements.
Published: 2001
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9. [Untitled]

Author: S. Urpo, A. G. Kislyakov, E. I. Shkelev, and V. V. Zaitsev
Subjects: Physics, Nuclear and High Energy Physics, Solar flare, business.industry, Astronomy and Astrophysics, Statistical and Nonlinear Physics, Dissipation, Electronic, Optical and Magnetic Materials, Computational physics, Optics, Modulation, Chirp, Electrical and Electronic Engineering, Electric current, business, Frequency modulation, Excitation, Microwave
Abstract: Using the Wigner-Ville transform, we study the dynamic spectra of low-frequency modulation of the intensity of microwave emission from several solar flares and detect the microwave bursts modulated by chirp signals (i.e., signals whose frequencies ω=ω0± kt, where k is a constant and t is the time) with a positive chirp rate. Such a modulation corresponds to the process of energy accumulation in the corresponding coronal magnetic loop (CML). We also detect chirp modulation with a negative chirp rate corresponding to powerful dissipation of electric current in the CML during a solar flare. The chirp modulation of the intensity of microwave emission from a CML arises from the excitation of eigenoscillations of the loop as an equivalent electric circuit. In this case, the modulation frequency is proportional to the loop electric current and varies with the variation of the latter. The electric-current values found for a few events using the dynamic spectra of chirp signals lie in the range 1011-1012A, and the rate of energy increase (decrease) is estimated to be 1.4·1026-3·1029 erg/sec for the characteristic time scale τ≃ 103-4·104 sec. The events studied give evidence for the possibility of realizing the “circuit” model of solar flares under solar-corona conditions.
Published: 2001
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10. [Untitled]

Author: S. Urpo, V. V. Zaitsev, A. G. Kislyakov, E. I. Shkelev, and Alexander V. Stepanov
Subjects: Physics, Nuclear and High Energy Physics, Solar flare, business.industry, Frequency drift, Astronomy and Astrophysics, Statistical and Nonlinear Physics, Pulse sequence, Coronal loop, Plasma, Low frequency, Electronic, Optical and Magnetic Materials, Computational physics, Optics, Astrophysics::Solar and Stellar Astrophysics, Electrical and Electronic Engineering, Magnetohydrodynamics, business, Microwave
Abstract: We analyze low-frequency intensity fluctuations of the microwave emission from solar flares at frequencies 22 and 37 GHz. The three microwave bursts of durations of about 1 h, observed at the Metsahovi Radio Observatory (Finland) with the time resolution of 0.1 and 0.05 s, are studied. To obtain spectral-temporal characteristics of the low-frequency fluctuations, we apply the Wigner-Ville method, i.e., the time-lag Fourier transform of the “local” autocorrelation function of an analytical signal. As a result, we obtain for the first time the dynamical spectra of the low-frequency fluctuations, which are identified as MHD eigenoscillations of coronal magnetic loops. The features of the dynamical spectra testify that several types of low-frequency pulsations are excited in coronal magnetic loops during solar flares: 1) Fast and slow magnetosonic oscillations with periods of 1-1.5 s and 200-280 s, respectively. Fast magnetosonic oscillations appear as pulse trains of duration 100-200 s and have the positive frequency drift dν/ dt≈ 0.125 Hz/min and the frequency splitting δν≈ 0.05 Hz; 2) The eigenoscillations of a coronal magnetic loop as an equivalent electric circuit. The period of these oscillations is about 1 s during the initial stage of a microwave burst and increases gradually up to 4 s during the decay stage of the radio emission; and 3) Intensity modulation of the microwave radiation by a periodic pulse sequence with a period of about 1 s at the burst onset and about 2 s at its end. The parameters of the dynamical spectra and identification of the MHD pulsations allow us to obtain information on the loop parameters, such as the ratio of the loop radius to its length (r/L≈ 0.1), the ratio of the gas pressure to the magnetic-field pressure inside the loop (β ≈ 3· 10-3), the ratio of plasma densities outside and inside the loop, and the electric current in the coronal loop (I≈ 1.5 · 1012 A).
Published: 2001
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11. Microwave tomography of solar magnetic fields

Author: S. Urpo, A. Grebinskij, V. Bogod, K. Shibasaki, G. Gelfreikh, and Silja Pohjolainen
Subjects: Physics, Photosphere, Astrophysics::High Energy Astrophysical Phenomena, General Physics and Astronomy, Astronomy, Astrophysics, Coronal radiative losses, Corona, Magnetic field, Nanoflares, Physics::Space Physics, Radiative transfer, Astrophysics::Solar and Stellar Astrophysics, Chromosphere, Microwave
Abstract: We present a new technique for the measure- ment of magnetic elds in the solar chromosphere - corona through observations of its free-free microwave emission in intensity and polarization. We derive the decoupled radi- ation transfer equations for Stoke's parameters of I and V for circular polarized emission in plane-layer inhomo- geneous atmospheres and present a model solutions of in- version problem. We discuss the discrimination between contributions from the corona and the chromosphere to the observed brightness spectra from the quiet Sun and plage regions and propose a practical method of magnetic eld estimates, which was used both with single frequency (the Nobeyama Radioheliograph at 17 GHz) and multi fre- quency (RATAN at 1 16 GHz) observations and discuss the preliminary results. The proposed techniques may be useful as microwave magnetography at the corona base and for checks and improvements in the current problem of extrapolating magnetic elds from photosphere to corona.
Published: 2000
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12. Parametric interaction of coronal loops with p modes

Author: S. Urpo, V. V. Zaitsev, A. G. Kisliakov, and A. V. Stepanov
Subjects: Loop (topology), Physics, Photosphere, Amplitude, Solar flare, Control theory, Astrophysics::Solar and Stellar Astrophysics, Coronal loop, Parametric oscillator, Magnetohydrodynamics, Excitation, Computational physics
Abstract: Parametric resonance between p modes and eigenoscillations of coronal loops is studied. Observations of solar radio bursts revealed this effect in simultaneous excitation of loop oscillations with periods corresponding to the pumping-up frequency (5 min), subharmonic (10 min), and to the first upper frequency of parametric resonance (3.3 min). An interpretation in terms of a coronal magnetic loop as an equivalent electric circuit is given. Parametric resonance can work as a channel for transfer of energy from photospheric motions to stellar coronae. Individual Objects: Sun Introduction The heating of solar (up to 106–107 K) and stellar coronae (107–108 K) has been explained by a variety of mechanisms. In particular acoustic heating, reconnection, damping of MHDwaves, topological dissipation, microflares were discussed in this context, but without an obvious solution in sight. We consider here another possible origin of coronal heating dealing with parametric resonance between coronal loops and p modes. Parametric excitation of loop oscillations by p modes There is quite a lot of evidence of 5-min oscillations in the solar corona as inferred from TRACE and SOHO data (see e.g. De Moortel et al. 2002; De Pontieu et al. 2005) and Metsahovi observations at 11 and 37 GHz (Kislyakov et al. 2006; Zaitsev & Kislyakov 2006). Figure 1 presents the example of spectral analysis of the solar flare event on March 20, 2000 which revealed 10, 5, and 3.3 min oscillations. Why are p-mode oscillations driven by photosphere convection observed at the coronal level? De Pontieu et al. (2005) suggested a tunneling or direct propagation of photospheric oscillations into the outer atmosphere via slow MHD and shock waves. We interpret such kinds of events using the electric circuit model for a coronal loop (Zaitsev et al. 2000) and parametric resonance between acoustic eigenmodes of a loop and p modes. Indeed, 5min velocity oscillations of the photosphere modulate the electric current in a coronal loop foot point. Parametric resonance between photosphere oscillations and sound oscillations ω0 = k||cs of the loop appears. This effect reveals itself in the excitation of loop oscillations with periods of 5 min (pumping-up frequency ω), 10 min (sub-harmonic ω/2), and 3.3 min A. V. Stepanov, V. V. Zaitsev, A. G. Kisliakov, and S. Urpo 31 Figure 1: Spectrum of pulsations in the flare event on March 20, 2000 observed with the Metsahovi radio telescope at 37 GHz. The dashed line shows the frequency of the 1.8 mHz (10 min period), while the solid vertical lines indicate the frequencies of 5-min (3.6 mHz) and 3.3-min (5.6 mHz) oscillations. (corresponding to the first upper frequency of parametric resonance 3ω/2). Modulation of electric current leads to modulation of sound velocity in a loop (Zaitsev & Kislyakov 2006): cs = „ 2γkBT mi «1/2 „ 1 + ΔT 2T « = cs0(1 + 0.5q cosωt), q = 4 3 γ − 1 γ I 2 πc2r2p I∼ I . Here p is the gas pressure, r is the loop radius, k|| = sπ/L, L is the loop length, s = 1, 2, 3, ... , I I∼. Deviations of loop plasma parameters can be written as d2y dt2 + ω 0(1 + q cosωt)y = 0 Here the parameter q is determined by the width of zones near the frequencies of a parametric resonance ωn = nω/2, n = 1, 2, 3, ... where the parametric instability occurs (Landau & Lifshitz 1976). The width of the first instability zone (−qω0/2 < ω/2−ω0 < qω0/2), where ω0 is close to ω/2, is larger. So, the amplitude of variations of sound speed under action of photospheric oscillations is higher compared to the second considerably narrowed zone ω ≈ ω0 if q 1 (Fig. 1). Since p modes cannot directly penetrate into the corona, the parametric resonance may work as an effective channel for transfer of energy of photospheric oscillations to the upper layers of the atmosphere. It offers the challenge to understanding the heating mechanism of stellar coronae. Estimations made for solar loops have shown that if the current exceeds 7 × 109 A, the energy flux of sound oscillations arising in the coronal magnetic loop as a result of parametric resonance exceeds losses due to optical radiation. 32 Parametric interaction of coronal loops with p modes Conclusions Hindman & Jain (2008) proposed recently that loop oscillations are generated due to the buffeting excitation of loop magnetic fibrils by p modes. They supposed however that magnetic fields are potential and no electric current exists. Our mechanism suggests the interaction of p modes with electric currents in coronal loop and the heating of loop foot points due to the dissipation of the electric currents. Because p modes do not penetrate into the corona, the parametric resonance is a good way for transfer of energy of photosphere oscillations to stellar coronae. Acknowledgments. This work was partially supported by RFBR grant 09-02-00624-a, the Program of Russian Academy of Sciences “Solar Activity and Physical Processes in the Sun-Earth System”, and the grants of Leading Scientific Schools NSH-4485.2008.2 and NSH-6110.2008.2.
Published: 2009
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13. [Untitled]

Author: S. Urpo, Hubertus Wöhl, V. Ruždjak, Roman Brajša, Bojan Vršnak, and Silja Pohjolainen
Subjects: Physics, Sunspot, business.industry, media_common.quotation_subject, Astronomy and Astrophysics, Angular velocity, Astrophysics, Statistical weight, Asymmetry, Optics, Space and Planetary Science, Brightness temperature, Differential rotation, Solar rotation, business, Microwave, media_common
Abstract: Daily full-disk solar maps obtained at 37 GHz in the years 1979, 1980, 1981, 1982, 1987, 1988, 1989, 1990, and 1991 are analysed and compared with full-disk solar maps in Hα. A search for a difference in the measured angular rotation velocity for two classes of microwave low-brightness-temperature regions (LTRs), associated and not associated with Hα filaments, is performed. Procedures with and without statistical weights, assigned to angular rotation velocities according to the tracing time, are applied and the statistical significance of the results is discussed. A higher angular rotation velocity is measured for LTRs associated with Hα filaments than for the not-associated ones. This angular velocity difference is interpreted as a consequence of a height difference between these two types of LTR tracers. Changes of the solar differential rotation velocity during the activity cycle measured using LTRs as tracers are explained by the measured cycle-dependence of the association rate between LTRs and Hα filaments. Similarly, the north–south asymmetry in the solar rotation velocity measured tracing LTRs is explained by the measured north–south asymmetry in the association rate between LTRs and Hα filaments. The rotation velocity of LTRs and Hα filaments is on the average more rigid in comparison with sunspots.
Published: 1999
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14. Fifteen years monitoring of extragalactic radio sources at 22, 37 and 87 GHz

Author: H. Teräsranta, M. Tornikoski, A. Mujunen, K. Karlamaa, T. Valtonen, N. Henelius, S. Urpo, M. Lainela, T. Pursimo, K. Nilsson, S. Wiren, A. Lähteenmäki, M. Korpi, R. Rekola, P. Heinämäki, M. Hanski, P. Nurmi, K. Kokkonen, P. Keinänen, O. Joutsamo, J. Oksanen, H. Pietil, E. Valtaoja, M. Valtonen, and P. Könönen
Subjects: Physics, Active galactic nucleus, Continuum (measurement), General Physics and Astronomy, Astronomy, Millimeter, Quasar, Astrophysics, Data reduction
Abstract: Over 13600 continuum observations of extragalactic sources are presented. These observations of 157 sources at 22, 37 and 87 GHz more than doubles the millimeter observations of these sources. The data are between 1990.5 and 1995.5, and combined with our earlier published data they form a 15 year database.
Published: 1998
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15. Multiresolution analysis of solar mm–wave bursts

Author: A. Krüger, Jürgen Kurths, S. Urpo, Udo Schwarz, and Bernhard Kliem
Subjects: Physics, Spectral index, Fractional Brownian motion, Solar flare, Astrophysics::High Energy Astrophysical Phenomena, Multiresolution analysis, General Physics and Astronomy, Flux, Wavelet transform, Astrophysics, Computational physics, Classical mechanics, Time series, Scaling
Abstract: Two methods of multi-scale time series analysis are applied to solar mm-wavelength flux time profiles in order to assess the diagnostic power of these tools for the exploration of nonlinear energy release processes. Both the multiresolution analysis (MRA), a method based on the wavelet transform, and the structure function analysis (SFA) permit the treatment of non-stationary time series. In addition, the MRA offers a local decomposition of the scaling behavior of the flux variations. Our main emphasis is directed at a decomposition of the contributions of the different time scales to the overall flux profile. The methods yield consistent values of the "spectral index" which describes the scalings contained in the time series. We find that time profiles of bursts are qualitatively analogous to fractional Brownian motion (fBm), possessing long-range temporal correlations. Such correlations are not found in quiet Sun observations. The MRA of six solar mm-wave bursts shows that the radio flux is always composed of contributions from a broad range of time scales. Also during the main phase of bursts, which appears to be structurally analogous to the pre- and post-burst phases at a resolution limit of 1 s, flux fluctuations are enhanced in a broad range of time scales. This suggests that the mm-wave bursts are composed of unresolved elements, just as the pre- and post-burst time profiles. The underlying energy release thus appears to be fragmentary. These results are discussed in terms of the avalanche model and plasma physical models for solar energy release events.
Published: 1998
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16. A multifrequency analysis of radio variability of blazars

Author: C. Bongardo, S. Urpo, H. D. Aller, Margo F. Aller, G. de Zotti, Roberto Tagliaferri, Giuseppe Longo, Harri Teräsranta, Angelo Ciaramella, Merja Tornikoski, Anne Lähteenmäki, Leopoldo Milano, A., Ciaramella, C., Bongardo, H. D., Aller, M. F., Aller, G., DE ZOTTI, A., Lahteenmaki, Longo, Giuseppe, Milano, Leopoldo, R., Tagliaferri, H., Terasranta, M., Tornikoski, and AND S., Urpo
Subjects: Radiation mechanisms: non-thermal, FOS: Physical sciences, Flux, Astrophysics, 01 natural sciences, symbols.namesake, Radio continuum: general, Radio observatory, 0103 physical sciences, Planck, signal processing, Blazar, 010303 astronomy & astrophysics, Methods: statistical, Physics, 010308 nuclear & particles physics, Galaxies: BL Lacertae objects: general, Astrophysics (astro-ph), radiation mechanisms, non linear PCA, Astronomy and Astrophysics, Quasar, Galaxies: active, Light curve, CMB cold spot, Intensity (physics), Space and Planetary Science, symbols
Abstract: We have carried out a multifrequency analysis of the radio variability of blazars, exploiting the data obtained during the extensive monitoring programs carried out at the University of Michigan Radio Astronomy Observatory (UMRAO, at 4.8, 8, and 14.5 GHz) and at the Metsahovi Radio Observatory (22 and 37 GHz). Two different techniques detect, in the Metsahovi light curves, evidences of periodicity at both frequencies for 5 sources (0224+671, 0945+408, 1226+023, 2200+420, and 2251+158). For the last three sources consistent periods are found also at the three UMRAO frequencies and the Scargle (1982) method yields an extremely low false-alarm probability. On the other hand, the 22 and 37 GHz periodicities of 0224+671 and 0945+408 (which were less extensively monitored at Metsahovi and for which we get a significant false-alarm probability) are not confirmed by the UMRAO database, where some indications of ill-defined periods about a factor of two longer are retrieved. We have also investigated the variability index, the structure function, and the distribution of intensity variations of the most extensively monitored sources. We find a statistically significant difference in the distribution of the variability index for BL Lac objects compared to flat-spectrum radio quasars (FSRQs), in the sense that the former objects are more variable. For both populations the variability index steadily increases with increasing frequency. The distribution of intensity variations also broadens with increasing frequency, and approaches a log-normal shape at the highest frequencies. We find that variability enhances by 20-30% the high frequency counts of extragalactic radio-sources at bright flux densities, such as those of the WMAP and Planck surveys., Comment: A&A accepted. 12 pages, 16 figures
Published: 2004

17. [Untitled]

Author: S. Urpo, E. Valtaoja, Henry Aurass, and Silja Pohjolainen
Subjects: Physics, Astrophysics::High Energy Astrophysical Phenomena, Astronomy and Astrophysics, Observable, Astrophysics::Cosmology and Extragalactic Astrophysics, Electron, Astrophysics, Plasma oscillation, law.invention, Magnetic field, Space and Planetary Science, law, Thermal, Event (particle physics), Microwave, Flare
Abstract: Two small radio flares following the great gamma-ray burst on 11 June 1991 are studied. We analyse the different association of emission features at microwaves, decimeter waves, and soft and hard X-rays for the events. The first flare has well-defined emission features in microwaves and soft and hard X-rays, and a faint decimetric signature well after the hard X-ray burst. It is not certain if the decimetric event is connected to the burst features. The second event is characterized by an almost simultaneous appearance of hard X-ray burst maxima and decimetric narrowband drift bursts, but soft X-ray emission is missing from the event. With the exception of the possibility that the soft X-ray emission is absorbed along the way, the following models can explain the reported differences in the second event: (1) Microwave emission in the second event is produced by ≤150 keV electrons spiraling in the magnetic field relatively low in the corona, while the hard X-ray emission is produced at the beginning of the burst near the loop top as thick-target emission. If the bulk of electrons entered the loop, the low-energy electrons would not be effectively mirrored and would eventually hit the footpoints and cause soft X-ray emission by evaporation, which was not observed. The collisions at the loop top would not produce observable plasma heating. The observed decimetric type III bursts could be created by plasma oscillations caused by electron beams traveling along the magnetic field lines at low coronal heights. (2) Microwave emission is caused by electrons with MeV energies trapped in the large magnetic loops, and the electrons are effectively mirrored from the loop footpoints. The hard X-ray emission can come both from the loop top and the loop footpoints as the accelerated lower energy electrons are not mirrored. The low-energy electrons are not, however, sufficient to create observable soft X-ray emission. The type III emission in this case could be formed either at low coronal heights or in local thick regions in the large loops, high in the corona.
Published: 1997
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18. Impulsive acceleration during gradual type solar radio flares

Author: S. Urpo, E. Valtaoja, and Silja Pohjolainen
Subjects: Physics, Atmospheric Science, Astrophysics::High Energy Astrophysical Phenomena, Bremsstrahlung, Aerospace Engineering, Astronomy, Flux, Astronomy and Astrophysics, Astrophysics, Solar radio, Plasma, Acceleration, Wavelength, Geophysics, Space and Planetary Science, Thermal, Extremely high frequency, General Earth and Planetary Sciences
Abstract: Gradual rise and fall type solar radio flares recorded at 37 GHz (8 mm wavelength) are analysed and compared with simultaneous soft and hard X-ray events. Emission measures and plasma temperatures were calculated from the GOES soft X-ray data, and optically thin thermal bremsstrahlung flux at 37 GHz was calculated assuming the same emitting volumes. The main emission mechanism behind the millimeter wave radio flares was determined to be thermal bremsstrahlung although many of the flares showed impulsive, non-thermal features. The radio flares were compared with simultaneous BATSE hard X-ray events, but significant temporal correlation was not found. It is suggested that there might be two different types of gradual radio flares, connected to gradual or more impulsive hard X-ray events. Another explanation for the observed two types would be different viewing angles to the emitting regions.
Published: 1997
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19. [Untitled]

Author: Roman Brajša, Bojan Vršnak, A. Schroll, S. Urpo, V. Ruždjak, Hubertus Wöhl, and Silja Pohjolainen
Subjects: Protein filament, Physics, Meteorology, Space and Planetary Science, Brightness temperature, Equator, Differential rotation, Solar rotation, Astronomy and Astrophysics, Astrophysics, Rotation, Maxima, Latitude
Abstract: The solar rotation rate obtained using the microwave Low-brightness-Temperature Regions (LTRs) as tracers in the heliographic range ± 55° from the years 1979–1980, 1981–1982, 1987–1988, and 1989–1991 varied from 3% to 4% in medium latitudes, and below 1% at the equator. Using Hα filaments as tracers at higher latitudes from the years 1979, 1980, 1982, 1984, and 1987, the solar rotation rate variation was between 2% and 8%. This represents an upper limit on the rotation rate variation during the solar activity cycle. Such changes could be caused by short-lived, large-scale velocity patterns on the solar surface. The Sun revealed a higher rotation rate on the average during the maxima of the solar activity cycles 21 and 22, i.e., in the periods 1979–1980 and 1989–1991, respectively, which differs from the rotation rates (lower on the average) in some years, 1981–1982 and 1987–1988, between the activity maximum and minimum (LTR data). Simultaneous comparison of rotation rates from LTRs and Hα filament tracings was possible in very limited time intervals and latitude bands only, and no systematic relationship was found, although the rotation rates determined by LTRs were mostly smaller than the rotation rates determined by Hα filaments. The errors obtained by applying different fitting procedures of the LTR data were analyzed, as well as the influence of the height correction. Finally, the north–south asymmetry in the rotation rate investigated by LTRs indicates that the southern solar hemisphere rotated slower in the periods under consideration, the difference being about 1%. The reliability of all obtained results is discussed and a comparison with other related studies was performed.
Published: 1997
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20. RadioAstron -- a Telescope with a Size of 300 000 km: Main Parameters and First Observational Results

Author: N. S. Kardashev, V. V. Khartov, V. V. Abramov, V. Yu. Avdeev, A. V. Alakoz, Yu. A. Aleksandrov, S. Ananthakrishnan, V. V. Andreyanov, A. S. Andrianov, N. M. Antonov, M. I. Artyukhov, M. Yu. Arkhipov, W. Baan, N. G. Babakin, V. E. Babyshkin, N. Bartel’, K. G. Belousov, A. A. Belyaev, J. J. Berulis, B. F. Burke, A. V. Biryukov, A. E. Bubnov, M. S. Burgin, G. Busca, A. A. Bykadorov, V. S. Bychkova, V. I. Vasil’kov, K. J. Wellington, I. S. Vinogradov, R. Wietfeldt, P. A. Voitsik, A. S. Gvamichava, I. A. Girin, L. I. Gurvits, R. D. Dagkesamanskii, L. D’Addario, G. Giovannini, D. L. Jauncey, P. E. Dewdney, A. A. D’yakov, V. E. Zharov, V. I. Zhuravlev, G. S. Zaslavskii, M. V. Zakhvatkin, A. N. Zinov’ev, Yu. Ilinen, A. V. Ipatov, B. Z. Kanevskii, I. A. Knorin, J. L. Casse, K. I. Kellermann, Yu. A. Kovalev, Yu. Yu. Kovalev, A. V. Kovalenko, B. L. Kogan, R. V. Komaev, A. A. Konovalenko, G. D. Kopelyanskii, Yu. A. Korneev, V. I. Kostenko, A. N. Kotik, B. B. Kreisman, A. Yu. Kukushkin, V. F. Kulishenko, D. N. Cooper, A. M. Kut’kin, W. H. Cannon, M. G. Larionov, M. M. Lisakov, L. N. Litvinenko, S. F. Likhachev, L. N. Likhacheva, A. P. Lobanov, S. V. Logvinenko, G. Langston, K. McCracken, S. Yu. Medvedev, M. V. Melekhin, A. V. Menderov, D. W. Murphy, T. A. Mizyakina, Yu. V. Mozgovoi, N. Ya. Nikolaev, B. S. Novikov, I. D. Novikov, V. V. Oreshko, Yu. K. Pavlenko, I. N. Pashchenko, Yu. N. Ponomarev, M. V. Popov, A. Pravin-Kumar, R. A. Preston, V. N. Pyshnov, I. A. Rakhimov, V. M. Rozhkov, J. D. Romney, P. Rocha, V. A. Rudakov, A. Räisänen, S. V. Sazankov, B. A. Sakharov, S. K. Semenov, V. A. Serebrennikov, R. T. Schilizzi, D. P. Skulachev, V. I. Slysh, A. I. Smirnov, J. G. Smith, V. A. Soglasnov, K. V. Sokolovskii, L. H. Sondaar, V. A. Stepan’yants, M. S. Turygin, S. Yu. Turygin, A. G. Tuchin, S. Urpo, S. D. Fedorchuk, A. M. Finkel’shtein, E. B. Fomalont, I. Fejes, A. N. Fomina, Yu. B. Khapin, G. S. Tsarevskii, J. A. Zensus, A. A. Chuprikov, M. V. Shatskaya, N. Ya. Shapirovskaya, A. I. Sheikhet, A. E. Shirshakov, A. Schmidt, L. A. Shnyreva, V. V. Shpilevskii, R. D. Ekers, and V. E. Yakimov
Subjects: Active galactic nucleus, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, law.invention, Radio telescope, Telescope, Astrophysical jet, law, Instrumentation and Methods for Astrophysics (astro-ph.IM), Astrophysics::Galaxy Astrophysics, Physics, Supermassive black hole, Star formation, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Planetary system, Astrophysics - Astrophysics of Galaxies, Galaxy, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: The Russian Academy of Sciences and Federal Space Agency, together with the participation of many international organizations, worked toward the launch of the RadioAstron orbiting space observatory with its onboard 10-m reflector radio telescope from the Baikonur cosmodrome on July 18, 2011. Together with some of the largest ground-based radio telescopes and a set of stations for tracking, collecting, and reducing the data obtained, this space radio telescope forms a multi-antenna ground-space radio interferometer with extremely long baselines, making it possible for the first time to study various objects in the Universe with angular resolutions a million times better than is possible with the human eye. The project is targeted at systematic studies of compact radio-emitting sources and their dynamics. Objects to be studied include supermassive black holes, accretion disks, and relativistic jets in active galactic nuclei, stellar-mass black holes, neutron stars and hypothetical quark stars, regions of formation of stars and planetary systems in our and other galaxies, interplanetary and interstellar plasma, and the gravitational field of the Earth. The results of ground-based and inflight tests of the space radio telescope carried out in both autonomous and ground-space interferometric regimes are reported. The derived characteristics are in agreement with the main requirements of the project. The astrophysical science program has begun., 54 pages, 11 figures; published by Astronomicheskij Zhurnal (in Russian) and Astronomy Reports (in English)
Published: 2013

21. A multi-wavelength study of a series of solar flares on June 11, 1991

Author: R Herrmann, S. Urpo, and Silja Pohjolainen
Subjects: Physics, Atmospheric Science, X-ray astronomy, Solar flare, Aerospace Engineering, Astronomy, Astronomy and Astrophysics, Astrophysics, Solar physics, Wavelength, Geophysics, Space and Planetary Science, Temporal resolution, General Earth and Planetary Sciences, H-alpha, Microwave, Radio astronomy
Abstract: On June 11, 1991, at 8:00–9:30 UT, several flares were observed in the active region 6659 (N38W24). We have studied the time development, fine-structures, spectral features, polarization, and correlation between different wavelengths of each of these events. The data used in the analysis are Metsahovi and Bern microwave data, GOES7 soft X-ray data, and other wavelength information from the Solar Geophysical Data.
Published: 1996
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22. Helium 10830 Å measurements of the Sun

Author: V. Ruždjak, Bojan Vršnak, T. Sakurai, Roman Brajša, S. Urpo, Hubertus Wöhl, and Silja Pohjolainen
Subjects: Physics, Solar observatory, Astrophysics::Instrumentation and Methods for Astrophysics, Coronal hole, Astronomy, Astronomy and Astrophysics, Astrophysics, Coronal loop, Corona, law.invention, Telescope, Space and Planetary Science, Limb darkening, law, Observatory, Physics::Space Physics, Coronal mass ejection, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: Measurements of the Sun in the near-infrared He i 10830 A absorption line were performed using the echelle spectrograph with a dispersion of 6.71 mA per pixel at the Vacuum Tower Telescope (German Solar Telescopes, Teide Observatory, Izana, Tenerife, Spain) on May 26, 1993. These measurements were compared with full-disc soft X-ray images of the Sun (Japanese solar satellite Yohkoh), full-disc solar images in Hα (Big Bear Solar Observatory), full-disc solar images in the He i 10830 A line (National Solar Observatory, Kitt Peak) and with full-disc microwave solar maps at 37 GHz (Metsahovi Radio Research Station). In the He 10830 A line the Sun displays a limb darkening similar to that in the visible part of the spectrum. Active regions and Hα filaments show a strong absorption in the He 10830 A line, whereas the absorption is weak in coronal holes.
Published: 1996
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23. Comparison of mm-wave and X-ray diagnostics of flare plasma

Author: V. V. Zaitsev, A. V. Stepanov, N. M. Bakhareva, and S. Urpo
Subjects: Physics, education.field_of_study, Solar flare, Astrophysics::High Energy Astrophysical Phenomena, Population, Bremsstrahlung, Astronomy and Astrophysics, Astrophysics, Plasma, law.invention, Space and Planetary Science, law, Physics::Space Physics, Plasma diagnostics, Emission spectrum, education, Chromosphere, Flare
Abstract: To compare mm-wave and X-ray diagnostics of solar flare plasma, five flares observed in 1980–1991 in Metsahovi at 22 and 37 GHz and with GOES, SMM, and GRO are studied. The first impulsive peak of the mm-wave bursts under investigation coincides in time with hard X-ray emission. The second gradual component in mm-wave emission coincides with the maximum of the soft X-ray emission measure. The bremsstrahlung mm-wave radiation from hot chromospheric plasma and gyrosynchrotron radiation driven by common population of superthermal electrons are calculated. It is shown that for mm-wave events with the first peak intensity ≤ 100 s.f.u., the thermal bremsstrahlung is more important than the gyrosynchrotron emission. The total energy of fast electrons deduced from the first peak of mm-wave bursts is one to two orders of magnitude less than that determined from the hard X-ray emission in the approximation of a thick-target nonthermal model. That can testify in favour of the hybrid thermal/nonthermal model proposed by Holman and Benka (1992). The emission measure and the energy of evaporated plasma using both mm-wave and soft X-ray data are also determined. For events investigated here the energy of evaporated chromospheric plasma is larger than the total energy of fast electron beams. We have concluded that, for evaporation, additional energy release in the chromosphere is needed. The possibility of such energy release in the framework of an advanced circuit model for solar flares is discussed.
Published: 1994
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24. Millimeter wave radiation sources visible in solar corona

Author: S. Urpo, S. Pohjolainen, and A. Kr�ger
Subjects: Space and Planetary Science, Astronomy and Astrophysics
Published: 1994
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25. Isotopic Composition of Light Nuclei in Cosmic Rays: Results from AMS-01

Author: H. T. Liu, J. Ulbricht, P. Extermann, H. Hofer, G. Ambrosi, U. Becker, E. Perrin, C. Sbarra, W. J. Burger, F. J. Eppling, P. H. Fisher, S. M. Ting, M. Kraeber, Rui Miguel Faisca Rodrigues Pereira, Veronica Bindi, T. Kirn, M. Paniccia, C. dela Guia, A. Klimentov, Adrian Biland, M.W. Lee, M. Pimenta, Jouko Ritakari, Hui Zhang, S. Schael, I. D'Antone, D. Rapin, Sadakazu Haino, J. Casaus, Massimo Gervasi, Jungwook Shin, V. Plyaskin, P. Azzarello, F. Mayet, A. Schultz von Dratzig, D. Grandi, Andrea Contin, J.V. Allaby, L. Djambazov, Andrei Kounine, P. G. Rancoita, M. Pohl, B. Bertucci, Xiao-Dong Tang, J. P. Vialle, W.Z. Zhu, M. Capell, R. Siedling, Shih-Chang Lee, H. Park, L. Ao, J. Engelberg, M. Jongmanns, R. Kossakowski, H. von Gunten, D. Crespo, J. D. Burger, K. Lübelsmeyer, J. Alcaraz, K. Karlamaa, Yun-Young Choi, S. X. Wu, Eun-Suk Seo, T. S. Dai, S. Xu, Dawei Zhao, Federico Cindolo, Z.R. Dong, V. Shoutko, Joachim Trümper, Maria Ionica, Guohuai Zhu, V. Commichau, Z.P. Zhang, E. Shoumilov, E. Riihonen, A. Mihul, G.P. Barreira, M. J. Boschini, M. Ribordy, Tengfei Song, H. Anderhub, M. Duranti, U. Roeser, T. Siedenburg, H.F. Chen, M. Steuer, C. Delgado, Mao-Zhi Yang, Zhenghao Xu, A. Lebedev, Dong-Chul Son, H. Suter, G.S. Sun, A. Bartoloni, V. Koutsenko, Eino Valtonen, W. Wallraff, P.C. Xia, F. Spada, P. Saouter, J. Favier, Z. L. Ren, Waclaw Karpinski, X. D. Cai, Changgen Yang, I. Vetlitsky, W.H. Park, E. Cortina-Gil, G. Bruni, F. Palmonari, A. Pevsner, D. Vité, M. Buénerd, Tzihong Chiueh, S. R. Ro, S. Natale, G. Laurenti, S. Waldmeier Wicki, E. P. Velikhov, B. Zimmermann, R. Becker, Y. Galaktionov, Roald Z. Sagdeev, Ciaran Williams, Merja Tornikoski, J.L. Yan, Markus Cristinziani, J. J. Torsti, Antonino Zichichi, L. Bellagamba, K.S. Kim, A. Arefiev, F. Barao, R. R. McNeil, Jing Wang, G. Sartorelli, Nicola Tomassetti, P. Cannarsa, Y. H. Chang, T. Eronen, G. Kenney, M. Aguilar, Felicitas Pauss, V. Hermel, Werner Lustermann, Behcet Alpat, M. Basile, Z.G. Chen, G. Flügge, G. N. Kim, F. Spinella, M. Bourquin, H. L. Zhuang, J. Yang, You Zhou, Nicolas Produit, D. Luckey, F. Vezzu, G. Lu, C. Maña, C.H. Lin, Samuel C.C. Ting, Fabrizio Giulio Luca Pilo, G. Castellini, J. Vandenhirtz, D. Casadei, G. Laborie, P. Giusti, S. Di Falco, O. Grimm, Paolo Zuccon, A. Hasan, Mauro Menichelli, F. Giovacchini, G. Schwering, Daijin Kim, W.Q. Gu, F. Zhou, N. Fouque, I. Cernuda, E. Fiandrini, H. S. Chen, D. Santos, S. Urpo, G. Viertel, Luísa Arruda, G. Lamanna, K. Hangarter, Lucio Quadrani, B. Verlaat, P. Berges, Ari Mujunen, K. Wiik, J. Berdugo, G. Boella, N.A. Chernoplekov, Anselmo Margotti, W. Hungerford, Timo Laitinen, M. Pauluzzi, D. Ren, Giuseppe Levi, Lu Yuzhang, LinLi Yan, A.I. Oliva, V. Pojidaev, C. Lechanoine-Leluc, S.W. Ye, Roberto Battiston, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), AMS, AGUILAR M., ALCARAZ J., ALLABY J., ALPAT B., AMBROSI G., ANDERHUB H., AO L., AREFIEV A., ARRUDA L., AZZARELLO P., BASILE M., BARAO F., BARREIRA G., BARTOLONI A., BATTISTON R., BECKER R., BECKER U., BELLAGAMBA L., BERDUGO J., BERGES P., BERTUCCI B., BILAND A., BINDI V., BOELLA G., BOSCHINI M., BOURQUIN M., BRUNI G., BUENERD M., BURGER JD., BURGER WJ., CAI XD., CANNARSA P., CAPELL M., CASADEI D., CASAUS J., CASTELLINI G., CERNUDA I., CHANG YH., CHEN HF., CHEN HS., CHEN ZG., CHERNOPLEKOV NA., CHIUEH TH., CHOI YY., CINDOLO F., COMMICHAU V., CONTIN A., CORTINA-GIL E., CRESPO D., CRISTINZIANI M., DAI TS., DELA GUIA C., DELGADO C., DI FALCO S., DJAMBAZOV L., D'ANTONE I., DONG ZR., DURANTI M., ENGELBERG J., EPPLING FJ., ERONEN T., EXTERMANN P., FAVIER J., FIANDRINI E., FISHER PH., FLUGGE G., FOUQUE N., GALAKTIONOV Y., GERVASI M., GIOVACCHINI F., GIUSTI P., GRANDI D., GRIMM O., GU WQ., HAINO S., HANGARTER K., HASAN A., HERMEL V., HOFER H., HUNGERFORD W., IONICA M., JONGMANNS M., KARLAMAA K., KARPINSKI W., KENNEY G., KIM DH., KIM GN., KIM KS., KIRN T., KLIMENTOV A., KOSSAKOWSKI R., KOUNINE A., KOUTSENKO V., KRAEBER M., LABORIE G., LAITINEN T., LAMANNA G., LAURENTI G., LEBEDEV A., LECHANOINE-LELUC C., LEE MW., LEE SC., LEVI G., LIN CH., LIU HT., LU G., LU YS., LUBELSMEYER K., LUCKEY D., LUSTERMANN W., MANA C., MARGOTTI A., MAYET F., MCNEIL RR., MENICHELLI M., MIHUL A., MUJUNEN A., NATALE S., OLIVA A., PALMONARI F., PANICCIA M., PARK HB., PARK WH., PAULUZZI M., PAUSS F., PEREIRA R., PERRIN E., PEVSNER A., PILO F., PIMENTA M., PLYASKIN V., POJIDAEV V., POHL M., PRODUIT N., QUADRANI L., RANCOITA PG., RAPIN D., REN D., REN Z., RIBORDY M., RIIHONEN E., RITAKARI J., RO S., ROESER U., SAGDEEV R., SANTOS D., SARTORELLI G., SAOUTER P., SBARRA C., SCHAEL S., VON DRATZIG AS., SCHWERING G., SEO ES., SHIN JW., SHOUMILOV E., SHOUTKO V., SIEDENBURG T., SIEDLING R., SON D., SONG T., SPADA FR., SPINELLA F., STEUER M., SUN GS., SUTER H., TANG XW., TING SCC., TING SM., TOMASSETTI N., TORNIKOSKI M., TORSTI J., TRUMPER J., ULBRICHT J., URPO S., VALTONEN E., VANDENHIRTZ J., VELIKHOV E., VERLAAT B., VETLITSKY I., VEZZU F., VIALLE JP., VIERTEL G., VITE D., VON GUNTEN H., WICKI SW., WALLRAFF W., WANG JZ., WIIK K., WILLIAMS C., WU SX., XIA PC., XU S., XU ZZ., YAN JL., YAN LG., YANG CG., YANG J., YANG M., YE SW., ZHANG HY., ZHANG ZP., ZHAO DX., ZHOU F., ZHOU Y., ZHU GY., ZHU WZ., ZHUANG HL., ZICHICHI A., ZIMMERMANN B., ZUCCON P, Aguilar, M, Alcaraz, J, Allaby, J, Alpat, B, Ambrosi, G, Anderhub, H, Ao, L, Arefiev, A, Arruda, L, Azzarello, P, Basile, M, Barao, F, Barreira, G, Bartoloni, A, Battiston, R, Becker, R, Becker, U, Bellagamba, L, Berdugo, J, Berges, P, Bertucci, B, Biland, A, Bindi, V, Boella, G, Boschini, M, Bourquin, M, Bruni, G, Buénerd, M, Burger, J, Burger, W, Cai, X, Cannarsa, P, Capell, M, Casadei, D, Casaus, J, Castellini, G, Cernuda, I, Chang, Y, Chen, H, Chen, Z, Chernoplekov, N, Chiueh, T, Choi, Y, Cindolo, F, Commichau, V, Contin, A, Cortina Gil, E, Crespo, D, Cristinziani, M, Dai, T, dela Guia, C, Delgado, C, Di Falco, S, Djambazov, L, D’Antone, I, Dong, Z, Duranti, M, Engelberg, J, Eppling, F, Eronen, T, Extermann, P, Favier, J, Fiandrini, E, Fisher, P, Flügge, G, Fouque, N, Galaktionov, Y, Gervasi, M, Giovacchini, F, Giusti, P, Grandi, D, Grimm, O, Gu, W, Haino, S, Hangarter, K, Hasan, A, Hermel, V, Hofer, H, Hungerford, W, Ionica, M, Jongmanns, M, Karlamaa, K, Karpinski, W, Kenney, G, Kim, D, Kim, G, Kim, K, Kirn, T, Klimentov, A, Kossakowski, R, Kounine, A, Koutsenko, V, Kraeber, M, Laborie, G, Laitinen, T, Lamanna, G, Laurenti, G, Lebedev, A, Lechanoine Leluc, C, Lee, M, Lee, S, Levi, G, Lin, C, Liu, H, Lu, G, Lu, Y, Lübelsmeyer, K, Luckey, D, Lustermann, W, Maña, C, Margotti, A, Mayet, F, Mcneil, R, Menichelli, M, Mihul, A, Mujunen, A, Natale, S, Oliva, A, Palmonari, F, Paniccia, M, Park, H, Park, W, Pauluzzi, M, Pauss, F, Pereira, R, Perrin, E, Pevsner, A, Pilo, F, Pimenta, M, Plyaskin, V, Pojidaev, V, Pohl, M, Produit, N, Quadrani, L, Rancoita, P, Rapin, D, Ren, D, Ren, Z, Ribordy, M, Riihonen, E, Ritakari, J, Ro, S, Roeser, U, Sagdeev, R, Santos, D, Sartorelli, G, Saouter, P, Sbarra, C, Schael, S, von Dratzig, A, Schwering, G, Seo, E, Shin, J, Shoumilov, E, Shoutko, V, Siedenburg, T, Siedling, R, Son, D, Song, T, Spada, F, Spinella, F, Steuer, M, Sun, G, Suter, H, Tang, X, Ting, S, Tomassetti, N, Tornikoski, M, Torsti, J, Trümper, J, Ulbricht, J, Urpo, S, Valtonen, E, Vandenhirtz, J, Velikhov, E, Verlaat, B, Vetlitsky, I, Vezzu, F, Vialle, J, Viertel, G, Vité, D, Von Gunten, H, Wicki, S, Wallraff, W, Wang, J, Wiik, K, Williams, C, Wu, S, Xia, P, Xu, S, Xu, Z, Yan, J, Yan, L, Yang, C, Yang, J, Yang, M, Ye, S, Zhang, H, Zhang, Z, Zhao, D, Zhou, F, Zhou, Y, Zhu, G, Zhu, W, Zhuang, H, Zichichi, A, Zimmermann, B, Zuccon, P, Massachusetts Institute of Technology. Department of Physics, Massachusetts Institute of Technology. Laboratory for Nuclear Science, Becker, R., Becker, Ulrich J., Berges, P., Burger, Joseph D., Cai, Xudong, Capell, Michael H., Dai, T. S., Eppling, Frederic J., Fisher, Peter H., Klimentov, A., Kounine, Andrei, Koutsenko, Vladimir, Lebedev, Alexei, Luckey, P. David, Jr., Shoutko, V., Siedenburg, T., Steuer, M., Ting, Samuel C. C., Wu. S. X., Xu, S., and Zhou, F.
Subjects: Nuclear reaction, Astrophysics and Astronomy, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], genetic structures, Cosmic ray, Isotopes of boron, 01 natural sciences, High Energy Physics - Experiment, Nuclear physics, ACCELERATION OF PARTICLES, ABUNDANCES, Nucleosynthesis, 0103 physical sciences, Alpha Magnetic Spectrometer, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], acceleration of particles, cosmic rays, nuclear reactions, nucleosynthesis, abundances, 010303 astronomy & astrophysics, Cosmic ray spallation, Physics, NUCLEAR REACTIONS, NUCLEOSYNTHESIS, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astronomy and Astrophysics, COSMIC RAYS, FIS/01 - FISICA SPERIMENTALE, Space and Planetary Science, Isotopes of beryllium, Astrophysics - High Energy Astrophysical Phenomena, Heliosphere
Abstract: The variety of isotopes in cosmic rays allows us to study different aspects of the processes that cosmic rays undergo between the time they are produced and the time of their arrival in the heliosphere. In this paper, we present measurements of the isotopic ratios [superscript 2]H/[superscript 4]He, [superscript 3]He/[superscript 4]He, [superscript 6]Li/[superscript 7]Li, [superscript 7]Be/([superscript 9]Be+[superscript 10]Be), and [superscript 10]B/[superscript 11]B in the range 0.2-1.4 GeV of kinetic energy per nucleon. The measurements are based on the data collected by the Alpha Magnetic Spectrometer, AMS-01, during the STS-91 flight in 1998 June., United States. Dept. of Energy, Massachusetts Institute of Technology
Published: 2011
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26. Diagnostics of solar flare and evaporated plasma using mm-wave emission

Author: S. Urpo, A. V. Stepanov, and V. V. Zaitsev
Subjects: Physics, Solar flare, Astrophysics::High Energy Astrophysical Phenomena, Bremsstrahlung, Astronomy and Astrophysics, Plasma, Astrophysics, Plasma oscillation, law.invention, Alfvén wave, Physics::Plasma Physics, Space and Planetary Science, law, Physics::Space Physics, Astrophysics::Solar and Stellar Astrophysics, Plasma diagnostics, Atomic physics, Chromosphere, Flare
Abstract: Pulsations of mm-wave emission with a period of about 5 s, which occurred during the impulsive phase of the flare of June 22, 1989, are investigated. It has been shown that these pulsations can be driven by Alfvenic oscillations of a flare loop excited due to upward motion of the chromospheric evaporated plasma. A method is proposed to determine the density and temperature of the evaporated plasma as well as the flare loop magnetic field and loop length in terms of Alfvenic oscillations of the loop and bremsstrahlung mechanism of mm-wave emission. The estimation of evaporated plasma energy has shown that for the flare of June 22, 1989 the energy content in electron beams is insufficient for chromospheric plasma evaporation. It is not excluded that the main energy release process occurs in the chromosphere.
Published: 1992
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27. Large-scale patterns on the Sun observed in the millimetric wavelength range

Author: Bojan Vršnak, V. Ruzdjak, H. Teräsranta, S. Jurac, S. Urpo, Silja Pohjolainen, Roman Brajša, and Z. Mouradian
Subjects: Physics, Butterfly diagram, business.industry, Equator, Astronomy and Astrophysics, Astrophysics, Solar physics, Solar prominence, Latitude, Magnetic field, Optics, Space and Planetary Science, Brightness temperature, Astrophysics::Solar and Stellar Astrophysics, H-alpha, Astrophysics::Earth and Planetary Astrophysics, business
Abstract: The nature and behaviour of large-scale patterns on the solar surface, indicated by the areas of brightness-temperature depressions in the millimetric wavelength range, is studied. A large sample of 346 individual, low-temperature regions (LTRs) was employed to provide reliable statistical evidence. An association of 99% was found between the locations of LTRs and the large-scale magnetic field inversion lines, and 60% of the LTRs were associated with the inversion line filaments. A tentative physical association with filaments is reconsidered, and one particularly well-observed case is presented. The heights of the perturbers causing brightness-temperature depressions are discussed. The long-term evolution of the latitudinal distribution of LTRs is presented in a butterfly diagram. Two belts of low-temperature regions outline the active region belts, shifting with them towards the equator during the solar activity cycle. The low-temperature region belts of the forthcoming cycle appear already at the maximum of the actual cycle at latitudes of about 55 °. The superpositions of the temperature minima distributions in the synoptic maps show patterns appearing as ‘giant cells’ and compatible with indications inferred from magnetographic data. The reliability of the inferred cells is considered, and a statistical analysis reveals a negligible probability for an accidental distribution appearing in the form of giant cells.
Published: 1992
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28. Solar differential rotation determined by polar crown filaments

Author: S. Urpo, Bojan Vršnak, V. Ruždjak, H. Teräsranta, Silja Pohjolainen, Roman Brajša, and A. Schroll
Subjects: Physics, business.industry, Astronomy and Astrophysics, Angular velocity, Solar radius, Rotation, Molecular physics, Optics, Space and Planetary Science, Sidereal time, Solar rotation, Differential rotation, Polar, Helioseismology, business
Abstract: The rotation rates obtained by tracing 124 polar crown filaments are presented in comparison with previous results. Higher filament rotation rate in polar regions was detected and discussed in terms of the various phenomena such as: the projection effect due to the height of measured tracers, the connection of polar filaments with the magnetic field patterns which show an increase of the rotation rate at high latitudes, rigid rotation of polar filaments which form pivot points, and eventual change of the differential rotation law during the cycle. However, when the height correction for an average height of 1% of the solar radius is applied, the filament rotation rate in polar regions decreases. Then the rotation law becomes: Ω(φ) = 14.45 − 0.11 sin2 φ − 3.69 sin4 φ (° day−1, sidereal).
Published: 1991
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29. Microwave flare characteristics in 8 and 3 mm Metsähovi measurements compared with optical and H-alpha data

Author: Silja Pohjolainen, S. Urpo, Harri Teräsranta, and Merja Tornikoski
Subjects: Physics, Wavelength, Solar flare, law, Brightness temperature, Astronomy, H-alpha, Source tracking, Microwave, Flare, law.invention
Abstract: In 1989–1990 several microwave bursts were detected at 37 and 90 GHz (8 and 3 rnm wavelengths, respectively) during solar mapping or source tracking at the Metsahovi Radio Research Station, Finland. Nine of the events are analysed and discussed in this paper.
Published: 2008
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30. OJ287 as a binary system

Author: S. Urpo, Gene Byrd, M. Valtonen, L. Valtaoja, E. Valtaoja, Harri Teräsranta, A. Sillanpää, B. Sundelius, and S. Haarala
Subjects: Physics, Black hole, Supermassive black hole, Active galactic nucleus, Gravitational wave, Astrophysics, Binary system, Light curve, Orbital period, Galaxy
Abstract: The historical optical light curve of OJ287 shows repeated outbursts at 11.65 yr intervals. Making use of computer modeling, we interpret this as resulting from a 9 yr orbital period in a binary system. Variability time scales are used to construct a mass model of the binary system, with derived masses of 5.109 M⊙ and 2·107 M⊙, We discuss how binary systems such as in OJ287 may result from mergers of galaxies. We infer that the system must contain also a third supermassive black hole.
Published: 2008
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31. Motion of high latitude solar microwave sources and comparison with polar prominences

Author: H. Teräsranta, S. Urpo, A. Schroll, Roman Brajša, Bojan Vršnak, V. Ruzdjak, and Silja Pohjolainen
Subjects: Radio telescope, Protein filament, Physics, Wavelength, QUIET, Physics::Space Physics, Astrophysics::Solar and Stellar Astrophysics, Astronomy, Polar, Astrophysics::Earth and Planetary Astrophysics, Solar prominence, Microwave, Latitude
Abstract: Solar microwave sources at high solar latitudes have been observed with a 14 m radio telescope at the Metsahovi Radio Research Station in Finland. Several periods for observations were organized in 1986–1989 in order to detect sources close to the north and south pole of the Sun. Measurements at 22 and 37 GHz (wavelengths 14 and 8 mm respectively) have revealed the existence of high temperature and low temperature regions (relative to the quiet Sun level) at latitudes 50–80 degrees. The motions of these regions have been studied and compared with optical measurements of polar prominences. The temperature enhancement at 37 GHz is typically 100–400 K above the quiet Sun level (7800 K) at that frequency. Although in most cases temperature depression in a low temperature area amounts 50–300 K, at 37 GHz, the temperature drop in the low temperature area which was observed in July 1982 was as low as 900 K. The results of the radio measurements of the Sun at 22 and 37 GHz on high solar latitudes imply that high temperature areas correspond to polar faculae while low temperature areas correspond to polar prominences. The principal cause of the observed lower temperature area is the absorbtion by the filament.
Published: 2005
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32. Chain antenna

Author: M. Tiuri, S. Tallqvist, and S. Urpo
Published: 2005
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33. The Alpha Magnetic Spectrometer (AMS) on the International Space Station: Part I – results from the test flight on the space shuttle

Author: P. Extermann, H. Hofer, J.P. Richeux, Jose Maria Kenny, M. Jongmanns, H. Anderhub, P. Giusti, A. Hasan, Mauro Menichelli, G. Scolieri, Y.S. Lu, I. Lopes, S. Ro, G. Schwering, Eun-Suk Seo, L. Baldini, E. Lanciotti, F. Vezzu, Maria Ionica, S.W. Ye, V. Koutsenko, Eino Valtonen, M.Y. Kim, G. Sartorelli, D. Rapin, V. Plyaskin, Werner Lustermann, Behcet Alpat, W.Q. Gu, W.Z. Zhu, C. Delgado, E. Fiandrini, Yu. Galaktionov, D.H. Kim, J. Alcaraz, S. X. Wu, W.H. Park, Felicitas Pauss, B. Verlaat, P. Berges, K. Karlamaa, S.C.C. Ting, F. Palmonari, Zhenghao Xu, Zhuoxiang Ren, F. Velcea, Tzihong Chiueh, G. Barbier, H.B. Park, R. Kossakowski, A. Klimentov, S. Urpo, Ari Mujunen, A. Lebedev, Dong-Chul Son, G. Laurenti, K. Luebelsmeyer, E. Shoumilov, W. Hungerford, H. S. Chen, N. Produit, M. Buenerd, S. Waldmeier Wicki, M. Basile, E. Riihonen, A. Mihul, Timo Laitinen, J. Yang, V. Postolache, V. Pojidaev, M. Steuer, P.C. Xia, G.S. Sun, Jian Wang, M. Ribordy, K. Hangarter, H. L. Zhuang, M. Pauluzzi, Stefan Schael, H. Suter, Guohuai Zhu, G. Boella, X.W. Tang, M. Kraber, A. Pevsner, M. A. Huang, Mao-Zhi Yang, Tao Song, J.L. Yan, N.A. Chernoplekov, J. Vandenhirtz, Z.G. Chen, C. Camps, Ciaran Williams, D. Ren, D. Luckey, I. Vetlitsky, Samuel C.C. Ting, N. Dinu, Zhidong Zhang, Anselmo Margotti, E. Cortina-Gil, M. Bourquin, A. Papi, Adrian Biland, R. Ionica, L. Djambazov, Paolo Zuccon, A. Contin, I. D'Antone, M.W. Lee, Jungwook Shin, F. Barao, G. Castellini, J. P. Da Cunha, Gui Nyun Kim, N. Fouque, P. Levtchenko, Massimo Gervasi, Kyung-Suk Cho, J. D. Burger, F. Mayet, M. Pohl, P. Yeh, G. Lu, C. Maña, C. Lechanoine-Leluc, A. Schultz von Dratzig, C. Rossin, Hengchang Liu, A. Mourao, S. Blasko, G. Laborie, C. Sbarra, Peter H. Fisher, L.G. Yan, V. Hermel, J.D. Deus, X. D. Cai, M.J. Choi, O. Grimm, J. Casaus, M. Capell, Philipp Azzarello, R. Siedling, J. Berdugo, Yun Wang, A. Arefiev, Roald Z. Sagdeev, J. Engelberg, H. von Gunten, C.L. Liu, L. Bellagamba, Changgen Yang, D. Casadei, U. Roser, R. R. McNeil, B. Meillon, Giuseppe Levi, Y.L. Chuang, K. Wiik, P. Bene, Federico Cindolo, J. J. Torsti, Antonino Zichichi, L. Brocco, J. Ritakari, Y. H. Chang, G. Kenney, P. Cannarsa, Y.Y. Choi, D. Barancourt, J. Favier, Waclaw Karpinski, E. Babucci, U. Becker, Dawei Zhao, R. Becker, Z.R. Dong, E. Perrin, K.S. Kim, Claudia Cecchi, F. J. Eppling, M. Aguilar, V. Shoutko, S. Bizzaglia, G. Esposito, M. Pimenta, G. Fluegge, D. Grandi, B. Bertucci, D. Santos, G. Ambrosi, T. S. Dai, A. Pesci, B.C. Wang, D. Vité, G. Lamanna, G. Viertel, J. P. Vialle, H.F. Chen, G.P. Barreira, W. J. Burger, Frank Raupach, Roberto Battiston, L. Ao, J. Ulbricht, Hao Zhang, S.C. Lee, J. Trümper, P. Emonet, M. J. Boschini, V. Commichau, E. P. Velikhov, B. Zimmermann, Merja Tornikoski, Markus Cristinziani, T. Eronen, P. G. Rancoita, W. Wallraff, G. Bruni, Aguilar, M, Alcaraz, J, Allaby, J, Alpat, B, Ambrosi, G, Anderhub, H, Ao, L, Arefiev, A, Azzarello, P, Babucci, E, Baldini, L, Basile, M, Berdugo, J, Berges, P, Bertucci, B, Biland, A, Bizzaglia, S, Blasko, S, Boella, G, Boschini, M, Bourquin, M, Brocco, L, Bruni, G, Buenerd, M, Burger, J, Burger, W, Cai, X, Camps, C, Cannarsa, P, Capell, M, Casadei, D, Casaus, J, Castellini, G, Cecchi, C, Chang, Y, Chen, H, Chen, Z, Chernoplekov, N, Chiueh, T, Cho, K, Choi, M, Choi, Y, Chuang, Y, Cindolo, F, Commichau, V, Contin, A, Cortina-Gil, E, Cristinziani, M, da Cunha, J, Dai, T, Delgado, C, Deus, J, Dinu, N, Djambazov, L, D'Antone, I, Dong, Z, Emonet, P, Engelberg, J, Eppling, F, Eronen, T, Esposito, G, Extermann, P, Favier, J, Fiandrini, E, Fisher, P, Fluegge, G, Fouque, N, Galaktionov, Y, Gervasi, M, Giusti, P, Grandi, D, Grimms, O, Gu, W, Hangarter, K, Hasan, A, Hermel, V, Hofer, H, Huang, M, Hungerford, W, Ionica, M, Ionica, R, Jongmanns, M, Karlamaa, K, Karpinski, W, Kenney, G, Kenny, J, Kim, D, Kim, G, Kim, K, Kim, M, Klimentov, A, Kossakowski, R, Koutsenko, V, Kraeber, M, Laborie, G, Laitinen, T, Lamanna, G, Lanciotti, E, Laurenti, G, Lebedev, A, Lechanoine-Leluc, C, Lee, M, Lee, S, Levi, G, Levtchenko, P, Liu, C, Liu, H, Lopes, I, Lu, G, Lu, Y, Lubelsmeyer, K, Luckey, D, Lustermann, W, Mana, C, Margotti, A, Mayet, F, Mcneil, R, Meillon, B, Menichelli, M, Mihul, A, Mourao, A, Mujunen, A, Palmonari, F, Papi, A, Park, H, Park, W, Pauluzzi, M, Pauss, F, Perrin, E, Pesci, A, Pevsner, A, Pimenta, M, Plyaskin, V, Pojidaev, V, Pohl, M, Postolache, V, Produit, N, Rancoita, P, Rapin, D, Raupach, F, Ren, D, Ren, Z, Ribordy, M, Richeux, J, Riihonen, E, Ritakari, J, Ro, S, Roeser, U, Rossin, C, Sagdeev, R, Santos, D, Sartorelli, G, Sbarra, C, Schael, S, von Dratzig, A, Schwering, G, Scolieri, G, Seo, E, Shin, J, Shoutko, V, Shoumilov, E, Siedling, R, Son, D, Song, T, Steuer, M, Sun, G, Suter, H, Tang, X, Ting, S, Tornikoski, M, Torsti, J, Trumper, J, Ulbricht, J, Urpo, S, Valtonen, E, Vandenhirtz, J, Velcea, F, Velikhov, E, Verlaat, B, Vetlitsky, I, Vezzu, F, V, Jp, Viertel, G, Vite, D, Von Gunten, H, Wicki, S, Wallraff, W, Wang, B, Wang, J, Wang, Y, Wiik, K, Williams, C, Wu, S, Xia, P, Yan, J, Yan, L, Yang, C, Yang, J, Yang, M, Ye, S, Yeh, P, Xu, Z, Zhang, H, Zhang, Z, Zhao, D, Zhu, G, Zhu, W, Zhuang, H, Zichichi, A, Zimmermann, B, Zuccon, P, Ambrosi, Giovanni, Azzarello, Philipp, Bene, Pierre, Bourquin, Maurice, Cortina Gil, Eduardo, Cristinziani, Markus, Emonet, Pascal Philippe, Extermann, Pierre, Leluc, Catherine, Perrin, Eric, Pohl, Martin, Produit, Nicolas, Rapin, Divic Jean, Ribordy, Mathieu, Richeux, Jean-Pierre, Vite, Davide, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), AMS, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, CIEMAT, E-28040, Madrid, Spain, and UCL - SST/IRMP - Institut de recherche en mathématique et physique
Subjects: Physics, 010308 nuclear & particles physics, FIS/06 - FISICA PER IL SISTEMA TERRA E PER IL MEZZO CIRCUMTERRESTRE, General Physics and Astronomy, chemistry.chemical_element, Electron, ddc:500.2, 01 natural sciences, Spectral line, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Nuclear physics, FIS/05 - ASTRONOMIA E ASTROFISICA, Positron, Earth's magnetic field, FIS/01 - FISICA SPERIMENTALE, chemistry, 13. Climate action, Antiproton, 0103 physical sciences, Alpha Magnetic Spectrometer, Nucleon, 010303 astronomy & astrophysics, AMS, Cosmic Rays, Antimatter, Helium, FIS/04 - FISICA NUCLEARE E SUBNUCLEARE
Abstract: The Alpha Magnetic Spectrometer (AMS) was flown on the space shuttle Discovery during flight STS-91 (June 1998) in a 51.7 deg orbit at altitudes between 320 and 390 km. A search for antihelium nuclei in the rigidity range 1–140 GV was performed. No antihelium nuclei were detected at any rigidity. An upper limit on the flux ratio of antihelium to helium of < 1.1×10^−6 was obtained. The high energy proton, electron, positron, helium, antiproton and deuterium spectra were accurately measured. For each particle and nuclei two distinct spectra were observed: a higher energy spectrum and a substantial second spectrum. Positrons in the second spectrum were found to be much more abundant than electrons. Tracing particles from the second spectra shows that most of them travel for an extended period of time in the geomagnetic field, and that the positive particles (p and e+) and negative ones (e−) originate from two complementary geographic regions. The second helium spectrum flux over the energy range 0.1–1.2 GeV/nucleon was measured to be (6.3 ± 0.9) × 10^−3(m^2 s sr)^−1. Over 90 percent of the helium flux was determined to be 3He at the 90% confidence level
Published: 2002
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34. Cosmic protons

Author: J. Alcaraz, B. Alpat, G. Ambrosi, H. Anderhub, L. Ao, A. Arefiev, P. Azzarello, E. Babucci, L. Baldini, M. Basile, D. Barancourt, F. Barao, G. Barbier, G. Barreira, R. Battiston, R. Becker, U. Becker, L. Bellagamba, P. Béné, J. Berdugo, P. Berges, B. Bertucci, A. Biland, S. Bizzaglia, S. Blasko, G. Boella, M. Boschini, M. Bourquin, L. Brocco, G. Bruni, M. Buenerd, J.D. Burger, W.J. Burger, X.D. Cai, C. Camps, P. Cannarsa, M. Capell, D. Casadei, J. Casaus, G. Castellini, C. Cecchi, Y.H. Chang, H.F. Chen, H.S. Chen, Z.G. Chen, N.A. Chernoplekov, T.H. Chiueh, Y.L. Chuang, F. Cindolo, V. Commichau, A. Contin, P. Crespo, M. Cristinziani, J.P. da Cunha, T.S. Dai, J.D. Deus, N. Dinu, L. Djambazov, I. D'Antone, Z.R. Dong, P. Emonet, J. Engelberg, F.J. Eppling, T. Eronen, G. Esposito, P. Extermann, J. Favier, E. Fiandrini, P.H. Fisher, G. Fluegge, N. Fouque, Yu. Galaktionov, M. Gervasi, P. Giusti, D. Grandi, O. Grimm, W.Q. Gu, K. Hangarter, A. Hasan, V. Hermel, H. Hofer, M.A. Huang, W. Hungerford, M. Ionica, R. Ionica, M. Jongmanns, K. Karlamaa, W. Karpinski, G. Kenney, J. Kenny, W. Kim, A. Klimentov, R. Kossakowski, V. Koutsenko, M. Kraeber, G. Laborie, T. Laitinen, G. Lamanna, G. Laurenti, A. Lebedev, S.C. Lee, G. Levi, P. Levtchenko, C.L. Liu, H.T. Liu, I. Lopes, G. Lu, Y.S. Lu, K. Lübelsmeyer, D. Luckey, W. Lustermann, C. Maña, A. Margotti, F. Mayet, R.R. McNeil, B. Meillon, M. Menichelli, A. Mihul, A. Mourao, A. Mujunen, F. Palmonari, A. Papi, I.H. Park, M. Pauluzzi, F. Pauss, E. Perrin, A. Pesci, A. Pevsner, M. Pimenta, V. Plyaskin, V. Pojidaev, M. Pohl, V. Postolache, N. Produit, P.G. Rancoita, D. Rapin, F. Raupach, D. Ren, Z. Ren, M. Ribordy, J.P. Richeux, E. Riihonen, J. Ritakari, U. Roeser, C. Roissin, R. Sagdeev, G. Sartorelli, A. Schultz von Dratzig, G. Schwering, G. Scolieri, E.S. Seo, V. Shoutko, E. Shoumilov, R. Siedling, D. Son, T. Song, M. Steuer, G.S. Sun, H. Suter, X.W. Tang, Samuel C.C. Ting, S.M. Ting, M. Tornikoski, J. Torsti, J. Trümper, J. Ulbricht, S. Urpo, I. Usoskin, E. Valtonen, J. Vandenhirtz, F. Velcea, E. Velikhov, B. Verlaat, I. Vetlitsky, F. Vezzu, J.P. Vialle, G. Viertel, D. Vité, H. Von Gunten, S. Waldmeier Wicki, W. Wallraff, B.C. Wang, J.Z. Wang, Y.H. Wang, K. Wiik, C. Williams, S.X. Wu, P.C. Xia, J.L. Yan, L.G. Yan, C.G. Yang, M. Yang, S.W. Ye, P. Yeh, Z.Z. Xu, H.Y. Zhang, Z.P. Zhang, D.X. Zhao, G.Y. Zhu, W.Z. Zhu, H.L. Zhuang, A. Zichichi, B. Zimmermann, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), AMS, Alcaraz, J, Alpat, B, Ambrosi, G, Anderhub, H, Ao, L, Arefiev, A, Azzarello, P, Babucci, E, Baldini, L, Basile, M, Barancourt, D, Barao, F, Barbier, G, Barreira, G, Battiston, R, Becker, R, Becker, U, Bellagamba, L, Béné, P, Berdugo, J, Berges, P, Bertucci, B, Biland, A, Bizzaglia, S, Blasko, S, Boella, G, Boschini, M, Bourquin, M, Brocco, L, Bruni, G, Buenerd, M, Burger, J, Burger, W, Cai, X, Camps, C, Cannarsa, P, Capell, M, Casadei, D, Casaus, J, Castellini, G, Cecchi, C, Chang, Y, Chen, H, Chen, Z, Chernoplekov, N, Chiueh, T, Chuang, Y, Cindolo, F, Commichau, V, Contin, A, Crespo, P, Cristinziani, M, Cunha, J, Dai, T, Deus, J, Dinu, N, Djambazov, L, D'Antone, I, Dong, Z, Emonet, P, Engelberg, J, Eppling, F, Eronen, T, Esposito, G, Extermann, P, Favier, J, Fiandrini, E, Fisher, P, Fluegge, G, Fouque, N, Galaktionov, Y, Gervasi, M, Giusti, P, Grandi, D, Grimm, O, Gu, W, Hangarter, K, Hasan, A, Hermel, V, Hofer, H, Huang, M, Hungerford, W, Ionica, M, Ionica, R, Jongmanns, M, Karlamaa, K, Karpinski, W, Kenney, G, Kenny, J, Kim, W, Klimentov, A, Kossakowski, R, Koutsenko, V, Kraeber, M, Laborie, G, Laitinen, T, Lamanna, G, Laurenti, G, Lebedev, A, Lee, S, Levi, G, Levtchenko, P, Liu, C, Liu, H, Lopes, I, Lu, G, Lu, Y, Lübelsmeyer, K, Luckey, D, Lustermann, W, Maña, C, Margotti, A, Mayet, F, Mcneil, R, Meillon, B, Menichelli, M, Mihul, A, Mourao, A, Mujunen, A, Palmonari, F, Papi, A, Park, I, Pauluzzi, M, Pauss, F, Perrin, E, Pesci, A, Pevsner, A, Pimenta, M, Plyaskin, V, Pojidaev, V, Pohl, M, Postolache, V, Produit, N, Rancoita, P, Rapin, D, Raupach, F, Ren, D, Ren, Z, Ribordy, M, Richeux, J, Riihonen, E, Ritakari, J, Roeser, U, Roissin, C, Sagdeev, R, Sartorelli, G, Dratzig, A, Schwering, G, Scolieri, G, Seo, E, Shoutko, V, Shoumilov, E, Siedling, R, Son, D, Song, T, Steuer, M, Sun, G, Suter, H, Tang, X, Ting, S, Tornikoski, M, Torsti, J, Trümper, J, Ulbricht, J, Urpo, S, Usoskin, I, Valtonen, E, Vandenhirtz, J, Velcea, F, Velikhov, E, Verlaat, B, Vetlitsky, I, Vezzu, F, Vialle, J, Viertel, G, Vité, D, Gunten, H, Wicki, S, Wallraff, W, Wang, B, Wang, J, Wang, Y, Wiik, K, Williams, C, Wu, S, Xia, P, Yan, J, Yan, L, Yang, C, Yang, M, Ye, S, Yeh, P, Xu, Z, Zhang, H, Zhang, Z, Zhao, D, Zhu, G, Zhu, W, Zhuang, H, Zichichi, A, Zimmermann, B, Ambrosi, Giovanni, Azzarello, Philipp, Bene, Pierre, Bourquin, Maurice, Cristinziani, Markus, Emonet, Pascal Philippe, Extermann, Pierre, Perrin, Eric, Pohl, Martin, Produit, Nicolas, Rapin, Divic Jean, Ribordy, Mathieu, Richeux, Jean-Pierre, and Vite, Davide
Subjects: [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Nuclear and High Energy Physics, FIS/05 - ASTRONOMIA E ASTROFISICA, Cosmic rays: protons, FIS/01 - FISICA SPERIMENTALE, 010308 nuclear & particles physics, 0103 physical sciences, ddc:500.2, Nuclear Experiment, 010303 astronomy & astrophysics, 01 natural sciences, FIS/04 - FISICA NUCLEARE E SUBNUCLEARE
Abstract: The primary proton spectrum in the kinetic energy range 0.2 to 200 GeV was measured by the Alpha Magnetic Spectrometer (AMS) during space shuttle flight STS–91 at an altitude of 380 km. The complete data set combining three shuttle attitudes and including all known systematic effects is presented.
Published: 2001

35. On the Rigid Component in the Solar Rotation

Author: S. Pohjolainen, Hubertus Wöhl, B. Vrsnak, R. Brajsa, S. Urpo, V. Ruždjak, Hanslmeier, Arnold, Messerotti, Mauro, and Veronig, Astrid
Subjects: Physics, Component (thermodynamics), Brightness temperature, Rotation velocity, Solar rotation, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Tracing, Microwave
Abstract: A rigid component in the rotation velocity determined by tracing low brightness temperature regions in the microwave regime was found and interpreted in terms of their association rate (39%) with rigidly rotating “pivot-points”.
Published: 2001

36. Search for antihelium in cosmic rays

Author: Z.R. Dong, S. Bizzaglia, G. Ambrosi, J. Casaus, M. Pimenta, T. S. Dai, Samuel C.C. Ting, L. Djambazov, B.C. Wang, G. Molinari, A. Klimentov, B. Bertucci, S. X. Wu, R. Pilastrini, G. Lamanna, L.G. Yan, R. Siedling, J. Favier, Philipp Azzarello, J. J. Torsti, Antonino Zichichi, A. Hasan, Mauro Menichelli, L. Ao, Inkyu Park, J.P. Vialle, M. Steuer, P.C. Xia, Peter H. Fisher, Ilya Usoskin, P. G. Rancoita, Jing Wang, F. Palmonari, J. Isbert, M. Ribordy, G. Boella, H. von Gunten, P. Crespo, W. J. Burger, N. Fouque, R. Ionica, Federico Cindolo, J.P. Richeux, R. Cavalletti, D.X. Zhao, U. Roeser, N.A. Chernoplekov, C. G. Yang, Nicolas Produit, M. Buenerd, A. Cotta-Ramusino, R. Flaminio, J. P. Da Cunha, Anselmo Margotti, D. Rapin, V. Plyaskin, W. Kim, Roberto Battiston, G.Y. Zhu, W.Z. Zhu, G. Fluegge, G. Bruni, G. Viertel, P. Levtchenko, E. Fiandrini, G. Laurenti, K. Luebelsmeyer, S. Waldmeier Wicki, S.C. Lee, Yu. Galaktionov, F. Massera, D. Vité, J. Ulbricht, A. Chiarini, Hao Zhang, H. S. Chen, C. Rossin, G. Pancaldi, Felicitas Pauss, S. Recupero, Ciaran Williams, R. Kossakowski, W. Karpinski, J. Alcaraz, F. Barao, P. Yeh, E. Emonet, L.K. Ding, H.T. Liu, E. P. Velikhov, G. Torromeo, M. Basile, G.S. Sun, A. Pevsner, J.L. Yan, X. D. Cai, L. Baldini, F. Mezzanotte, C.L. Liu, L. Bellagamba, S. Blasko, K. Hangarter, J. Berdugo, Adrian Biland, G. Barbier, J. Vandenhirtz, V. Hermel, A. Arefiev, E. Prati, Jose Maria Kenny, R. R. McNeil, T.G. Guzik, B. Meillon, W.K. Gu, G. Kenney, I. D'Antone, J.P. Wefel, Markus Cristinziani, T. Eronen, R. Becker, Y.L. Chuang, P. Bene, B. Alpat, D. Luckey, E. Riihonen, A. Mihul, M. Jongmanns, C.C. Feng, D. Casadei, W. Wallraff, J. Krieger, H.L. Zhuang, G. Castellini, Massimo Gervasi, Zhuoxiang Ren, G. Schwering, W. Hungerford, A. Papi, Timo Laitinen, D. Santos, F. Tenbusch, B. Verlaat, P. Berges, Raffaele Mezzenga, S. Urpo, Ari Mujunen, G. Laborie, V. Shoutko, M. Pauluzzi, Y. S. Lu, G.P. Barreira, Yun Wang, V. Commichau, J. Truemper, A. Pesci, D. Ren, M. Capell, V. Koutsenko, Eino Valtonen, F. Vezzu, P. Cannarsa, C. Camps, T.P. Li, M. Ionica, H. Postema, A. Contin, M. Yang, E. Babucci, U. Becker, A. Lebedev, Dong-Chul Son, P. Giusti, I. Lopes, E. Perrin, F. J. Eppling, D. Alvisi, G. Lu, F. Raupach, C. Maña, P. Extermann, S. M. Ting, H. Hofer, G. Esposito, I. Vetlitsky, G. Sartorelli, M. Lolli, G. Maehlum, E.A. Werner, Fabio Finelli, Z.G. Chen, Werner Lustermann, Giuseppe Levi, X. W. Tang, Tao Song, M. Bourquin, V. Pojidaev, E. Shoumilov, H. Suter, J. D. Burger, Roald Z. Sagdeev, A. Mourao, J. Ritakari, Y. H. Chang, D. Barancourt, N. Dinu, H. Anderhub, Tzihong Chiueh, M. A. Huang, Jorge Dias de Deus, F. Mayet, A. Schultz von Dratzig, Alcaraz, J, Alvisi, D, Alpat, B, Ambrosi, G, Anderhub, H, Ao, L, Arefiev, A, Azzarello, P, Babucci, E, Baldini, L, Basile, M, Barancourt, D, Barao, F, Barbier, G, Barreira, G, Battiston, R, Becker, R, Becker, U, Bellagamba, L, Béné, P, Berdugo, J, Berges, P, Bertucci, B, Biland, A, Bizzaglia, S, Blasko, S, Boella, G, Bourquin, M, Bruni, G, Buenerd, M, Burger, J, Burger, W, Cai, X, Cavalletti, R, Camps, C, Cannarsa, P, Capell, M, Casadei, D, Casaus, J, Castellini, G, Chang, Y, Chen, H, Chen, Z, Chernoplekov, N, Chiarini, A, Chiueh, T, Chuang, Y, Cindolo, F, Commichau, V, Contin, A, Cotta Ramusino, A, Crespo, P, Cristinziani, M, Dacunha, J, Dai, T, Deus, J, Ding, L, Dinu, N, Djambazov, L, D'Antone, I, Dong, Z, Emonet, P, Eppling, F, Eronen, T, Esposito, G, Extermann, P, Favier, J, Feng, C, Fiandrini, E, Finelli, F, Fisher, P, Flaminio, R, Fluegge, G, Fouque, N, Galaktionov, Y, Gervasi, M, Giusti, P, Gu, W, Guzik, T, Hangarter, K, Hasan, A, Hermel, V, Hofer, H, Huang, M, Hungerford, W, Ionica, M, Ionica, R, Isbert, J, Jongmanns, M, Karpinski, W, Kenney, G, Kenny, J, Kim, W, Klimentov, A, Krieger, J, Kossakowski, R, Koutsenko, V, Laborie, G, Laitinen, T, Lamanna, G, Laurenti, G, Lebedev, A, Lee, S, Levi, G, Levtchenko, P, Li, T, Liu, C, Liu, H, Lolli, M, Lopes, I, Lu, G, Lu, Y, Lübelsmeyer, K, Luckey, D, Lustermann, W, Maehlum, G, Maña, C, Margotti, A, Massera, F, Mayet, F, Mcneil, R, Meillon, B, Menichelli, M, Mezzanotte, F, Mezzenga, R, Mihul, A, Molinari, G, Mourao, A, Mujunen, A, Palmonari, F, Pancaldi, G, Papi, A, Park, I, Pauluzzi, M, Pauss, F, Perrin, E, Pesci, A, Pevsner, A, Pilastrini, R, Pimenta, M, Plyaskin, V, Pojidaev, V, Postema, H, Prati, E, Produit, N, Rancoita, P, Rapin, D, Raupach, F, Recupero, S, Ren, D, Ren, Z, Ribordy, M, Richeux, J, Riihonen, E, Ritakari, J, Roeser, U, Roissin, C, Sagdeev, R, Santos, D, Sartorelli, G, Schultzvondratzig, A, Schwering, G, Shoutko, V, Shoumilov, E, Siedling, R, Son, D, Song, T, Steuer, M, Sun, G, Suter, H, Tang, X, Ting, S, Tenbusch, F, Torromeo, G, Torsti, J, Trümper, J, Ulbricht, J, Urpo, S, Usoskin, I, Valtonen, E, Vandenhirtz, J, Velikhov, E, Verlaat, B, Vetlitsky, I, Vezzu, F, Vialle, J, Viertel, G, Vité, D, Vongunten, H, Waldmeierwicki, S, Wallraff, W, Wang, B, Wang, J, Wang, Y, Wefel, J, Werner, E, Williams, C, Wu, S, Xia, P, Yan, J, Yan, L, Yang, C, Yang, M, Yeh, P, Zhang, H, Zhao, D, Zhu, G, Zhu, W, Zhuang, H, Zichichi, A, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), and AMS
Subjects: Astrophysics and Astronomy, Nuclear and High Energy Physics, FOS: Physical sciences, chemistry.chemical_element, Space Shuttle, Cosmic ray, Astrophysics, 7. Clean energy, 01 natural sciences, High Energy Physics - Experiment, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], High Energy Physics - Experiment (hep-ex), FIS/05 - ASTRONOMIA E ASTROFISICA, Rigidity (electromagnetism), 0103 physical sciences, Alpha Magnetic Spectrometer, 010306 general physics, Helium, Physics, 010308 nuclear & particles physics, Astrophysics (astro-ph), Astronomy, Flux ratio, FIS/01 - FISICA SPERIMENTALE, chemistry, Cosmic rays: anti-helium, FIS/04 - FISICA NUCLEARE E SUBNUCLEARE
Abstract: The Alpha Magnetic Spectrometer (AMS) was flown on the space shuttle Discovery during flight STS-91 in a 51.7 degree orbit at altitudes between 320 and 390 km. A total of 2.86 * 10^6 helium nuclei were observed in the rigidity range 1 to 140 GV. No antihelium nuclei were detected at any rigidity. An upper limit on the flux ratio of antihelium to helium of < 1.1 * 10^-6 is obtained., 18 pages, Latex, 9 .eps figures
Published: 2000

37. Leptons in near earth orbit

Author: L. Djambazov, P. Giusti, G. Scolieri, I. Lopes, Dawei Zhao, P. G. Rancoita, E. Babucci, U. Becker, F. Vezzu, E. Perrin, F. J. Eppling, G. Barbier, S. M. Ting, S.C. Lee, R. Ionica, F. Palmonari, H. von Gunten, G. Esposito, Z.R. Dong, Federico Cindolo, Changgen Yang, H. T. Liu, Diego Casadei, Yu. Galaktionov, D. Vité, A. Lebedev, U. Roeser, G. Castellini, Dong-Chul Son, Z. L. Ren, J. Alcaraz, Guohuai Zhu, Yun Wang, S. Bizzaglia, A. Arefiev, P. Extermann, H. Hofer, W. Wallraff, Ilya Usoskin, Jing Wang, P. Levtchenko, P. Emonet, T. S. Dai, H. Anderhub, Waclaw Karpinski, E. Fiandrini, R. Becker, P. Cannarsa, R. R. McNeil, D. Rapin, C. Roissin, B.C. Wang, M. Pimenta, E. P. Velikhov, B. Zimmermann, V. Plyaskin, Roald Z. Sagdeev, B. Meillon, H. S. Chen, L. Baldini, J. Casaus, A. Hasan, E. Riihonen, Mauro Menichelli, K. Karlamaa, A. Mihul, Giovanna Bruni, G. Kenney, N. Produit, D. Grandi, M. Ribordy, S. Urpo, W. J. Burger, Merja Tornikoski, Markus Cristinziani, G. Schwering, A. Pesci, I. Vetlitsky, L.G. Yan, I. D'Antone, Y. H. Chang, Tengfei Song, W.Q. Gu, B. Bertucci, D. Barancourt, N. Dinu, V. Commichau, G. Laborie, P. Crespo, Mao-Zhi Yang, J. J. Torsti, M. Jongmanns, Antonino Zichichi, Adrian Biland, V. Postolache, Peter H. Fisher, T. Eronen, C. Camps, J. Berdugo, N. Fouque, J. P. Da Cunha, Massimo Gervasi, J. Vandenhirtz, H. F. Chen, F. Barao, S. Blasko, Zhenyu Zhang, H.L. Zhuang, G. Viertel, E. Shoumilov, Jose Maria Kenny, W. Hungerford, F. Velcea, Y.L. Chuang, O. Grimm, J.L. Yan, K. Wiik, P. Bene, H. Suter, J.P. Richeux, Tzihong Chiueh, V. Hermel, M. Buenerd, Timo Laitinen, M. Capell, A. Papi, Eun-Suk Seo, M. Pauluzzi, R. Siedling, G. Fluegge, W.Z. Zhu, Giovanni Ambrosi, L. Ao, M. Bourquin, D. Ren, G. Lu, C. Maña, V. Koutsenko, Eino Valtonen, Felicitas Pauss, R. Kossakowski, A. Klimentov, G.S. Sun, A. Contin, Samuel C.C. Ting, M. A. Huang, M. J. Boschini, M. Basile, K. Hangarter, Roberto Battiston, A. Pevsner, D. Luckey, F. Mayet, Ciaran Williams, J. Ulbricht, A. Schultz von Dratzig, P. Yeh, G. Laurenti, Claudia Cecchi, S. Waldmeier Wicki, Hao Zhang, Z.G. Chen, S. X. Wu, J. Ritakari, X. D. Cai, J. Trümper, V. Shoutko, Inkyu Park, M. Steuer, P.C. Xia, S.W. Ye, C.L. Liu, L. Bellagamba, G. Lamanna, J. Engelberg, Xiao-Dong Tang, J. P. Vialle, K. Lübelsmeyer, G.P. Barreira, M. Ionica, P. Azzarello, Z. Z. Xu, V. Pojidaev, B. Verlaat, G. Sartorelli, P. Berges, Giuseppe Levi, Lu Yuzhang, Ari Mujunen, Werner Lustermann, Behcet Alpat, J. D. Burger, Frank Raupach, A. Mourao, J.D. Deus, L. Brocco, G. Boella, N.A. Chernoplekov, Anselmo Margotti, W. Kim, M. Kraeber, J. Favier, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), AMS, Alcaraz, J, Alpat, B, Ambrosi, G, Anderhub, H, Ao, L, Arefiev, A, Azzarello, P, Babucci, E, Baldini, L, Basile, M, Barancourt, D, Barao, F, Barbier, G, Barreira, G, Battiston, R, Becker, R, Becker, U, Bellagamba, L, Béné, P, Berdugo, J, Berges, P, Bertucci, B, Biland, A, Bizzaglia, S, Blasko, S, Boella, G, Boschini, M, Bourquin, M, Brocco, L, Bruni, G, Buenerd, M, Burger, J, Burger, W, Cai, X, Camps, C, Cannarsa, P, Capell, M, Casadei, D, Casaus, J, Castellini, G, Cecchi, C, Chang, Y, Chen, H, Chen, Z, Chernoplekov, N, Chiueh, T, Chuang, Y, Cindolo, F, Commichau, V, Contin, A, Crespo, P, Cristinziani, M, Cunha, J, Dai, T, Deus, J, Dinu, N, Djambazov, L, D'Antone, I, Dong, Z, Emonet, P, Engelberg, J, Eppling, F, Eronen, T, Esposito, G, Extermann, P, Favier, J, Fiandrini, E, Fisher, P, Fluegge, G, Fouque, N, Galaktionov, Y, Gervasi, M, Giusti, P, Grandi, D, Grimm, O, Gu, W, Hangarter, K, Hasan, A, Hermel, V, Hofer, H, Huang, M, Hungerford, W, Ionica, M, Ionica, R, Jongmanns, M, Karlamaa, K, Karpinski, W, Kenney, G, Kenny, J, Kim, W, Klimentov, A, Kossakowski, R, Koutsenko, V, Kraeber, M, Laborie, G, Laitinen, T, Lamanna, G, Laurenti, G, Lebedev, A, Lee, S, Levi, G, Levtchenko, P, Liu, C, Liu, H, Lopes, I, Lu, G, Lu, Y, Lübelsmeyer, K, Luckey, D, Lustermann, W, Maña, C, Margotti, A, Mayet, F, Mcneil, R, Meillon, B, Menichelli, M, Mihul, A, Mourao, A, Mujunen, A, Palmonari, F, Papi, A, Park, I, Pauluzzi, M, Pauss, F, Perrin, E, Pesci, A, Pevsner, A, Pimenta, M, Plyaskin, V, Pojidaev, V, Postolache, V, Produit, N, Rancoita, P, Rapin, D, Raupach, F, Ren, D, Ren, Z, Ribordy, M, Richeux, J, Riihonen, E, Ritakari, J, Roeser, U, Roissin, C, Sagdeev, R, Sartorelli, G, Dratzig, A, Schwering, G, Scolieri, G, Seo, E, Shoutko, V, Shoumilov, E, Siedling, R, Son, D, Song, T, Steuer, M, Sun, G, Suter, H, Tang, X, Ting, S, Tornikoski, M, Torsti, J, Trümper, J, Ulbricht, J, Urpo, S, Usoskin, I, Valtonen, E, Vandenhirtz, J, Velcea, F, Velikhov, E, Verlaat, B, Vetlitsky, I, Vezzu, F, Vialle, J, Viertel, G, Vité, D, Gunten, H, Wicki, S, Wallraff, W, Wang, B, Wang, J, Wang, Y, Wiik, K, Williams, C, Wu, S, Xia, P, Yan, J, Yan, L, Yang, C, Yang, M, Ye, S, Yeh, P, Xu, Z, Zhang, H, Zhang, Z, Zhao, D, Zhu, G, Zhu, W, Zhuang, H, Zichichi, A, and Zimmermann, B
Subjects: Nuclear and High Energy Physics, Cosmic Rays, AMS, Cosmic ray, Electron, Astrophysics, Kinetic energy, 01 natural sciences, Spectral line, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Nuclear physics, FIS/05 - ASTRONOMIA E ASTROFISICA, AMS-01, 0103 physical sciences, Alpha Magnetic Spectrometer, AMS, 010306 general physics, 010303 astronomy & astrophysics, Physics, Earth's orbit, Cosmic rays: leptons, Cosmic Rays, cosmic rays, AMS-01, FIS/01 - FISICA SPERIMENTALE, Earth's magnetic field, 13. Climate action, High Energy Physics::Experiment, FIS/04 - FISICA NUCLEARE E SUBNUCLEARE, Lepton
Abstract: The lepton spectra in the kinetic energy ranges 0.2 to 40 GeV for e − and 0.2 to 3 GeV for e + were measured by the Alpha Magnetic Spectrometer (AMS) during space shuttle flight STS–91 at altitudes near 380 km. From the origin of the leptons two distinct spectra were observed: a higher energy spectrum and a substantial second spectrum with positrons much more abundant than electrons. Tracing leptons from the second spectra shows that most of these leptons travel for an extended period of time in the geomagnetic field and that the e + and e − originate from two complementary geographic regions.
Published: 2000

38. Helium in near earth orbit

Author: D. Vité, Peter H. Fisher, Yu. Galaktionov, J. Alcaraz, Roald Z. Sagdeev, D.X. Zhao, K. Karlamaa, A. Arefiev, S.W. Ye, E. Riihonen, W. Hungerford, M. A. Huang, R. R. McNeil, B. Meillon, V. Shoutko, G. Kenney, J. Ritakari, Y. H. Chang, J. Engelberg, C. Camps, G. Sartorelli, D. Barancourt, A. Mihul, Timo Laitinen, R. Ionica, Jorge Dias de Deus, W. Kim, H. von Gunten, P. G. Rancoita, V. Postolache, M. Pauluzzi, G. Lu, C. Maña, Werner Lustermann, Federico Cindolo, F. Mayet, G. Fluegge, Mao-Zhi Yang, D. Ren, A. Schultz von Dratzig, G. Barbier, W.Z. Zhu, W. J. Burger, A. Papi, J. Casaus, U. Roeser, M. Ribordy, G. Ambrosi, Y.L. Chuang, A. Contin, P. Levtchenko, M. Buenerd, X.W. Tang, M. Pimenta, W. Wallraff, T. S. Dai, F. Vezzu, B. Verlaat, Maria Ionica, G.S. Sun, Samuel C.C. Ting, Frank Raupach, E. Shoumilov, P. Berges, B.C. Wang, S. Urpo, Ari Mujunen, G. Bruni, H. Suter, P. Bene, Hengchang Liu, D. Rapin, C. Roissin, V. Plyaskin, G. Laurenti, S. Waldmeier Wicki, D. Grandi, A. Pevsner, Z. L. Ren, F. Velcea, Tao Song, G. Lamanna, M. J. Boschini, B. Bertucci, J. J. Torsti, Antonino Zichichi, Waclaw Karpinski, J. Berdugo, H. Anderhub, V. Commichau, R. Becker, Roberto Battiston, B. Alpat, N. Fouque, J.P. Richeux, Zhenghao Xu, M. Bourquin, A. Lebedev, Dong-Chul Son, E. Fiandrini, F. Palmonari, Yun Wang, G. Boella, P. Yeh, J.L. Yan, H.F. Chen, L. Brocco, Felicitas Pauss, L. Baldini, A. Pesci, H. S. Chen, J. Ulbricht, K. Wiik, R. Kossakowski, N.A. Chernoplekov, Nicolas Produit, K. Lübelsmeyer, S. X. Wu, M. Basile, P. Cannarsa, Hao Zhang, S. Blasko, M. Jongmanns, G. Castellini, E. P. Velikhov, B. Zimmermann, G.P. Barreira, K. Hangarter, H. L. Zhuang, Anselmo Margotti, Tzihong Chiueh, J. P. Da Cunha, Y.S. Lu, Inkyu Park, J.P. Vialle, Ciaran Williams, A. Klimentov, G. Laborie, L. Ao, M. Pohl, N. Dinu, Merja Tornikoski, Markus Cristinziani, M. Steuer, P.C. Xia, G. Viertel, D. Luckey, Jose Maria Kenny, J. Trümper, L. Djambazov, Paolo Zuccon, O. Grimm, T. Eronen, E. Babucci, U. Becker, I. Vetlitsky, S.C. Lee, Eun-Suk Seo, E. Perrin, M. Kraeber, F. J. Eppling, S. M. Ting, Changgen Yang, V. Koutsenko, Eino Valtonen, P. Giusti, Adrian Biland, G. Scolieri, G. Esposito, Z.R. Dong, Claudia Cecchi, Philipp Azzarello, I. Lopes, Massimo Gervasi, P. Emonet, S. Bizzaglia, Z.G. Chen, J. Favier, M. Capell, R. Siedling, X. D. Cai, C.L. Liu, L. Bellagamba, L.G. Yan, Ilya Usoskin, Jing Wang, J. Vandenhirtz, A. Hasan, Mauro Menichelli, G. Schwering, P. Extermann, W.Q. Gu, H. Hofer, F. Barao, V. Hermel, Zhidong Zhang, D. Casadei, I. D'Antone, Guohuai Zhu, J. D. Burger, A. Mourao, V. Pojidaev, Giuseppe Levi, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), AMS, Alcaraz, J, Alpat, B, Ambrosi, G, Anderhub, H, Ao, L, Arefiev, A, Azzarello, P, Babucci, E, Baldini, L, Basile, M, Barancourt, D, Barao, F, Barbier, G, Barreira, G, Battiston, R, Becker, R, Becker, U, Bellagamba, L, Béné, P, Berdugo, J, Berges, P, Bertucci, B, Biland, A, Bizzaglia, S, Blasko, S, Boella, G, Boschini, M, Bourquin, M, Brocco, L, Bruni, G, Buenerd, M, Burger, J, Burger, W, Cai, X, Camps, C, Cannarsa, P, Capell, M, Casadei, D, Casaus, J, Castellini, G, Cecchi, C, Chang, Y, Chen, H, Chen, Z, Chernoplekov, N, Chiueh, T, Chuang, Y, Cindolo, F, Commichau, V, Contin, A, Cristinziani, M, Cunha, J, Dai, T, Deus, J, Dinu, N, Djambazov, L, D'Antone, I, Dong, Z, Emonet, P, Engelberg, J, Eppling, F, Eronen, T, Esposito, G, Extermann, P, Favier, J, Fiandrini, E, Fisher, P, Fluegge, G, Fouque, N, Galaktionov, Y, Gervasi, M, Giusti, P, Grandi, D, Grimm, O, Gu, W, Hangarter, K, Hasan, A, Hermel, V, Hofer, H, Huang, M, Hungerford, W, Ionica, M, Ionica, R, Jongmanns, M, Karlamaa, K, Karpinski, W, Kenney, G, Kenny, J, Kim, W, Klimentov, A, Kossakowski, R, Koutsenko, V, Kraeber, M, Laborie, G, Laitinen, T, Lamanna, G, Laurenti, G, Lebedev, A, Lee, S, Levi, G, Levtchenko, P, Liu, C, Liu, H, Lopes, I, Lu, G, Lu, Y, Lübelsmeyer, K, Luckey, D, Lustermann, W, Maña, C, Margotti, A, Mayet, F, Mcneil, R, Meillon, B, Menichelli, M, Mihul, A, Mourao, A, Mujunen, A, Palmonari, F, Papi, A, Park, I, Pauluzzi, M, Pauss, F, Perrin, E, Pesci, A, Pevsner, A, Pimenta, M, Plyaskin, V, Pojidaev, V, Pohl, M, Postolache, V, Produit, N, Rancoita, P, Rapin, D, Raupach, F, Ren, D, Ren, Z, Ribordy, M, Richeux, J, Riihonen, E, Ritakari, J, Roeser, U, Roissin, C, Sagdeev, R, Sartorelli, G, Schultz&nbsp, von&nbsp, Dratzig, A, Schwering, G, Scolieri, G, Seo, E, Shoutko, V, Shoumilov, E, Siedling, R, Son, D, Song, T, Steuer, M, Sun, G, Suter, H, Tang, X, Ting, S, Tornikoski, M, Torsti, J, Trümper, J, Ulbricht, J, Urpo, S, Usoskin, I, Valtonen, E, Vandenhirtz, J, Velcea, F, Velikhov, E, Verlaat, B, Vetlitsky, I, Vezzu, F, Vialle, J, Viertel, G, Vité, D, Gunten, H, Wicki, S, Wallraff, W, Wang, B, Wang, J, Wang, Y, Wiik, K, Williams, C, Wu, S, Xia, P, Yan, J, Yan, L, Yang, C, Yang, M, Ye, S, Yeh, P, Xu, Z, Zhang, H, Zhang, Z, Zhao, D, Zhu, G, Zhu, W, Zhuang, H, Zichichi, A, Zimmermann, B, Zuccon, P, Ambrosi, Giovanni, Azzarello, Philipp, Bene, Pierre, Bourquin, Maurice, Cristinziani, Markus, Emonet, Pascal Philippe, Extermann, Pierre, Perrin, Eric, Pohl, Martin, Produit, Nicolas, Rapin, Divic Jean, Ribordy, Mathieu, Richeux, Jean-Pierre, and Vite, Davide
Subjects: Physics, Nuclear and High Energy Physics, Earth's orbit, Range (particle radiation), 010308 nuclear & particles physics, chemistry.chemical_element, Flux, ddc:500.2, 01 natural sciences, Spectral line, Nuclear physics, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], FIS/05 - ASTRONOMIA E ASTROFISICA, FIS/01 - FISICA SPERIMENTALE, Earth's magnetic field, chemistry, 0103 physical sciences, Alpha Magnetic Spectrometer, Atomic physics, Cosmic rays: helium, Nuclear Experiment, Nucleon, 010303 astronomy & astrophysics, FIS/04 - FISICA NUCLEARE E SUBNUCLEARE, Helium
Abstract: The helium spectrum from 0.1 to 100 GeV/nucleon was measured by the Alpha Magnetic Spectrometer (AMS) during space shuttle flight STS-91 at altitudes near 380 km. Above the geomagnetic cutoff the spectrum is parameterized by a power law. Below the geomagnetic cutoff a second helium spectrum was observed. In the second helium spectra over the energy range 0.1 to 1.2 GeV/nucleon the flux was measured to be (6.3±0.9)×10 −3 ( m 2 sec sr ) −1 and more than ninety percent of the helium was determined to be 3He (at the 90% CL). Tracing helium from the second spectrum shows that about half of the 3He travel for an extended period of time in the geomagnetic field and that they originate from restricted geographic regions similar to protons and positrons.
Published: 2000

39. Protons in near earth orbit

Author: J. Alcaraz, D. Alvisi, B. Alpat, G. Ambrosi, H. Anderhub, L. Ao, A. Arefiev, P. Azzarello, E. Babucci, L. Baldini, M. Basile, D. Barancourt, F. Barao, G. Barbier, G. Barreira, R. Battiston, R. Becker, U. Becker, L. Bellagamba, P. Béné, J. Berdugo, P. Berges, B. Bertucci, A. Biland, S. Bizzaglia, S. Blasko, G. Boella, M. Boschini, M. Bourquin, G. Bruni, M. Buenerd, J.D. Burger, W.J. Burger, X.D. Cai, R. Cavalletti, C. Camps, P. Cannarsa, M. Capell, D. Casadei, J. Casaus, G. Castellini, Y.H. Chang, H.F. Chen, H.S. Chen, Z.G. Chen, N.A. Chernoplekov, A. Chiarini, T.H. Chiueh, Y.L. Chuang, F. Cindolo, V. Commichau, A. Contin, A. Cotta–Ramusino, P. Crespo, M. Cristinziani, J.P. da Cunha, T.S. Dai, J.D. Deus, N. Dinu, L. Djambazov, I. D'Antone, Z.R. Dong, P. Emonet, J. Engelberg, F.J. Eppling, T. Eronen, G. Esposito, P. Extermann, J. Favier, C.C. Feng, E. Fiandrini, F. Finelli, P.H. Fisher, R. Flaminio, G. Fluegge, N. Fouque, Yu. Galaktionov, M. Gervasi, P. Giusti, D. Grandi, W.Q. Gu, K. Hangarter, A. Hasan, V. Hermel, H. Hofer, M.A. Huang, W. Hungerford, M. Ionica, R. Ionica, M. Jongmanns, K. Karlamaa, W. Karpinski, G. Kenney, J. Kenny, W. Kim, A. Klimentov, R. Kossakowski, V. Koutsenko, G. Laborie, T. Laitinen, G. Lamanna, G. Laurenti, A. Lebedev, S.C. Lee, G. Levi, P. Levtchenko, C.L. Liu, H.T. Liu, M. Lolli, I. Lopes, G. Lu, Y.S. Lu, K. Lübelsmeyer, D. Luckey, W. Lustermann, C. Maña, A. Margotti, F. Massera, F. Mayet, R.R. McNeil, B. Meillon, M. Menichelli, F. Mezzanotte, R. Mezzenga, A. Mihul, G. Molinari, A. Mourao, A. Mujunen, F. Palmonari, G. Pancaldi, A. Papi, I.H. Park, M. Pauluzzi, F. Pauss, E. Perrin, A. Pesci, A. Pevsner, R. Pilastrini, M. Pimenta, V. Plyaskin, V. Pojidaev, H. Postema, V. Postolache, E. Prati, N. Produit, P.G. Rancoita, D. Rapin, F. Raupach, S. Recupero, D. Ren, Z. Ren, M. Ribordy, J.P. Richeux, E. Riihonen, J. Ritakari, U. Roeser, C. Roissin, R. Sagdeev, D. Santos, G. Sartorelli, A. Schultz von Dratzig, G. Schwering, E.S. Seo, V. Shoutko, E. Shoumilov, R. Siedling, D. Son, T. Song, M. Steuer, G.S. Sun, H. Suter, X.W. Tang, Samuel C.C. Ting, S.M. Ting, M. Tornikoski, G. Torromeo, J. Torsti, J. Trümper, J. Ulbricht, S. Urpo, I. Usoskin, E. Valtonen, J. Vandenhirtz, F. Velcea, E. Velikhov, B. Verlaat, I. Vetlitsky, F. Vezzu, J.P. Vialle, G. Viertel, D. Vité, H. Von Gunten, S. Waldmeier Wicki, W. Wallraff, B.C. Wang, J.Z. Wang, Y.H. Wang, K. Wiik, C. Williams, S.X. Wu, P.C. Xia, J.L. Yan, L.G. Yan, C.G. Yang, M. Yang, S.W. Ye, P. Yeh, Z.Z. Xu, H.Y. Zhang, Z.P. Zhang, D.X. Zhao, G.Y. Zhu, W.Z. Zhu, H.L. Zhuang, A. Zichichi, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), AMS, Alcaraz, J, Alvisi, D, Alpat, B, Ambrosi, G, Anderhub, H, Ao, L, Arefiev, A, Azzarello, P, Babucci, E, Baldini, L, Basile, M, Barancourt, D, Barao, F, Barbier, G, Barreira, G, Battiston, R, Becker, R, Becker, U, Bellagamba, L, Béné, P, Berdugo, J, Berges, P, Bertucci, B, Biland, A, Bizzaglia, S, Blasko, S, Boella, G, Boschini, M, Bourquin, M, Bruni, G, Buenerd, M, Burger, J, Burger, W, Cai, X, Cavalletti, R, Camps, C, Cannarsa, P, Capell, M, Casadei, D, Casaus, J, Castellini, G, Chang, Y, Chen, H, Chen, Z, Chernoplekov, N, Chiarini, A, Chiueh, T, Chuang, Y, Cindolo, F, Commichau, V, Contin, A, Cotta–ramusino, A, Crespo, P, Cristinziani, M, Cunha, J, Dai, T, Deus, J, Dinu, N, Djambazov, L, D'Antone, I, Dong, Z, Emonet, P, Engelberg, J, Eppling, F, Eronen, T, Esposito, G, Extermann, P, Favier, J, Feng, C, Fiandrini, E, Finelli, F, Fisher, P, Flaminio, R, Fluegge, G, Fouque, N, Galaktionov, Y, Gervasi, M, Giusti, P, Grandi, D, Gu, W, Hangarter, K, Hasan, A, Hermel, V, Hofer, H, Huang, M, Hungerford, W, Ionica, M, Ionica, R, Jongmanns, M, Karlamaa, K, Karpinski, W, Kenney, G, Kenny, J, Kim, W, Klimentov, A, Kossakowski, R, Koutsenko, V, Laborie, G, Laitinen, T, Lamanna, G, Laurenti, G, Lebedev, A, Lee, S, Levi, G, Levtchenko, P, Liu, C, Liu, H, Lolli, M, Lopes, I, Lu, G, Lu, Y, Lübelsmeyer, K, Luckey, D, Lustermann, W, Maña, C, Margotti, A, Massera, F, Mayet, F, Mcneil, R, Meillon, B, Menichelli, M, Mezzanotte, F, Mezzenga, R, Mihul, A, Molinari, G, Mourao, A, Mujunen, A, Palmonari, F, Pancaldi, G, Papi, A, Park, I, Pauluzzi, M, Pauss, F, Perrin, E, Pesci, A, Pevsner, A, Pilastrini, R, Pimenta, M, Plyaskin, V, Pojidaev, V, Postema, H, Postolache, V, Prati, E, Produit, N, Rancoita, P, Rapin, D, Raupach, F, Recupero, S, Ren, D, Ren, Z, Ribordy, M, Richeux, J, Riihonen, E, Ritakari, J, Roeser, U, Roissin, C, Sagdeev, R, Santos, D, Sartorelli, G, Dratzig, A, Schwering, G, Seo, E, Shoutko, V, Shoumilov, E, Siedling, R, Son, D, Song, T, Steuer, M, Sun, G, Suter, H, Tang, X, Ting, S, Tornikoski, M, Torromeo, G, Torsti, J, Trümper, J, Ulbricht, J, Urpo, S, Usoskin, I, Valtonen, E, Vandenhirtz, J, Velcea, F, Velikhov, E, Verlaat, B, Vetlitsky, I, Vezzu, F, Vialle, J, Viertel, G, Vité, D, Gunten, H, Wicki, S, Wallraff, W, Wang, B, Wang, J, Wang, Y, Wiik, K, Williams, C, Wu, S, Xia, P, Yan, J, Yan, L, Yang, C, Yang, M, Ye, S, Yeh, P, Xu, Z, Zhang, H, Zhang, Z, Zhao, D, Zhu, G, Zhu, W, Zhuang, H, and Zichichi, A
Subjects: Nuclear and High Energy Physics, Astrophysics and Astronomy, Proton, FOS: Physical sciences, Flux, Space Shuttle, Astrophysics, Kinetic energy, 7. Clean energy, 01 natural sciences, High Energy Physics - Experiment, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], High Energy Physics - Experiment (hep-ex), FIS/05 - ASTRONOMIA E ASTROFISICA, 0103 physical sciences, Alpha Magnetic Spectrometer, Cosmic rays, AMS, AMS, Nuclear Experiment, 010303 astronomy & astrophysics, Cosmic rays, Physics, Range (particle radiation), Earth's orbit, 010308 nuclear & particles physics, Astrophysics (astro-ph), Earth's magnetic field, FIS/01 - FISICA SPERIMENTALE, 13. Climate action, Physics::Space Physics, cosmic rays: protons, FIS/04 - FISICA NUCLEARE E SUBNUCLEARE, Particle Physics - Experiment
Abstract: The proton spectrum in the kinetic energy range 0.1 to 200 GeV was measured by the Alpha Magnetic Spectrometer (AMS) during space shuttle flight STS-91 at an altitude of 380 km. Above the geomagnetic cutoff the observed spectrum is parameterized by a power law. Below the geomagnetic cutoff a substantial second spectrum was observed concentrated at equatorial latitudes with a flux ~ 70 m^-2 sec^-1 sr^-1. Most of these second spectrum protons follow a complicated trajectory and originate from a restricted geographic region., 19 pages, Latex, 7 .eps figures
Published: 2000

40. Large Scale Patterns on the Solar Surface Indicated by Microwave Observations

Author: B. Vršnak, S. Pohjolainen, H. Teräsranta, S. Urpo, R. Brajša, V. Ruždjak, A. Schroll, and S. Jurač
Abstract: A large set of observations of the Sun at 37 GHz is analysed. An association of 99% is found between the regions of brightness temperature depression and the magnetic field inversion lines. Observations indicate a possible existence of “giant cells” with duration of 1-2 years and a longitudinal extension up to 90°.
Published: 1991
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41. Rotation of Large Scale Patterns on the Solar Surface as Determined from Filament and Millimeter Data

Author: S. Pohjolainen, B. Vršnak, H. Teräsranta, S. Urpo, R. Brajša, V. Ruždjak, S. Jurač, and A. Schroll
Abstract: The rotation of large scale solar magnetic field patterns was studied using quiescent filaments and low temperature regions observed at 37 GHz as tracers.
Published: 1991
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42. Multi-frequency observations of radio enhanced temperature regions of the Sun

Author: S. Urpo, A.G. Tlatov, A. Riehokainen, and Esko Valtaoja
Subjects: Space and Planetary Science, Environmental science, Astronomy and Astrophysics, Remote sensing
Published: 2004
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43. Millimeter Wave Radiation Sources Visible in Solar Corona

Author: A. Krüger, S. Urpo, and S. Pohjolainen
Subjects: Physics, Electron density, Wavelength, Magnetic loop, Optics, business.industry, Brightness temperature, Extremely high frequency, Coronal mass ejection, Astrophysics, Radio frequency, Radiation, business
Abstract: Coronal millimeter wave sources (CMMS) have been observed at radio frequencies 22-90 GHz (at wavelengths 3-13 mm). The observed CMMS have been classified into three different categories according to their time scale and relation to other wavelength events. The CMMS indicate enhancement of electron density in the corona, as well as magnetic loop structures. The CMMS are evidence of dynamical processes taking place at the lower levels of the corona, propagating into the higher levels.
Published: 1994
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44. RELATION BETWEEN CORONAL mm-WAVE SOURCES, NOISE STORMS, AND CMEs

Author: J. Hildebrandt, A. Krüger, S. Urpo, and A. Böhme
Subjects: Physics, Photosphere, Coronal plane, Coronal mass ejection, Coronal cloud, Astronomy, Storm, Astrophysics, Coronal loop, Solar physics, Noise (radio)
Abstract: Coronal millimeter-wave sources (CMMSs) centered at heights in the solar atmosphere of the order of 100000 km above the photospheric level have been observed for more than ten years at the Metsahovi Radio Research Station of the Helsinki University of Technology. The CMMSs appear to form a special class of long-duration post-flare emission although their relationship to single flares is not always clearly established. There is an interesting relation to gradual microwave bursts and noise storms, and also to soft X-ray long-duration events (LDEs) and coronal mass ejections (CMEs). Results of these findings are discussed and consequences for the physical interpretation outlined.
Published: 1992
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45. Solar differential rotation determined by polar crown filaments

Author: Brajša, Roman, Vršnak, Bojan, Ruždjak, Vladimir, and A. Schroll, S. Pohjolainen, S. Urpo and H. Terasranta
Published: 1991

46. On the association between coronal mm-wave sources, LDE x-ray flares, and coronal mass ejections

Author: J. Hildebrandt, Silja Pohjolainen, S. Urpo, and A. Krüger
Subjects: Physics, Atmospheric Science, Photosphere, Solar flare, Aerospace Engineering, Astronomy, Astronomy and Astrophysics, Coronal loop, Astrophysics, Solar physics, Special class, law.invention, Geophysics, Space and Planetary Science, law, Coronal plane, Coronal mass ejection, General Earth and Planetary Sciences, Flare
Abstract: Coronal millimetre-wave sources (CMMSs) at heights of about 10 5 km above the photosphere and lifetimes of at least several hours are considered to form a special class of post-flare events providing interesting objects for plasma diagnostics. Based on observations for more than six years their relationship to long lasting X-ray emissions (LDEs) and great flare events is examined. Although only a part of CMMSs is found to be associated with LDEs at a time interval
Published: 1989
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47. Relationship of solar coronal millimetre wave sources to bursts in the centimetre range

Author: H. Teräsranta, J. Hildebrandt Potsdam, S. Urpo, V. Ruždjak, and A. Krüger
Subjects: Physics, Space and Planetary Science, Astronomy and Astrophysics, Statistical analysis, Astrophysics, Millimetre wave
Abstract: Les relations entre les ondes millimetriques solaires et les sursauts solaires sont analysees. Les ondes millimetriques coronales peuvent etre considerees comme indicateurs de systemes d'arches coronales de grande envergure (∼ 10 5 km) provenant de grandes regions actives solaires
Published: 1989
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48. On the correlation of microwave bursts with the Hα flares

Author: H. Teräsranta, S. Urpo, and V. Ruzdjak
Subjects: Physics, Atmospheric Science, Solar flare, Astrophysics::High Energy Astrophysical Phenomena, Aerospace Engineering, Astronomy, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Solar maximum, law.invention, Radio telescope, Solar wind, Geophysics, Space and Planetary Science, law, Observatory, Physics::Space Physics, Coronal mass ejection, Astrophysics::Solar and Stellar Astrophysics, General Earth and Planetary Sciences, Microwave, Flare
Abstract: The results of a direct comparison of solar microwave recordings at the Metsahovi Radio Research station, Finland, and H-alpha flares at the Hvar Observatory, Yugoslavia, during the Solar Maximum Year compaigns of 1979-1981 and 1983 are reported. At the Metsahovi station, a 14-meter radio telescope is used and at the Hvar Observatory a solar double-telescope is used. It is found that the correlation between H-alpha flares and microwave gradual rise and fall events (GRF), with a time scale of tens of minutes, is high. At Metsahovi, 23 GRF events are measured and in 22 cases (96 percent) a simultaneous flare is observed at Hvar. On the other hand, impulsive microwave bursts with a time scale of tens of seconds have low correlation with H-alpha flares. It is shown that the main contribution to the microwave GRF bursts comes from thermal radiation and that the correlation of flares and microwave events is low at long wavelengths and very high at shorter wavelengths. 6 references.
Published: 1984
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49. The spectrum of coronal sources at millimetre and centimetre waves

Author: S. Urpo, G. B. Gelfreikh, A. N. Korzhavin, V. M. Bogod, J. Hildebrandt, V. N. Borovik, and A. Krüger
Subjects: Physics, Brightness, Photosphere, business.industry, Bremsstrahlung, Astronomy and Astrophysics, Astrophysics, Polarization (waves), Wavelength, Optics, Space and Planetary Science, Brightness temperature, Degree of polarization, business, Radio wave
Abstract: Recently recognized solar millimetre-wave off-limb sources are interpreted as a special phenomenon of long-duration post- and inter-flare emission at coronal altitudes. We present, for the first time, information about the brightness and polarization spectrum in the centimetre range for one such event of September 22, 1980 by means of RATAN-600 observations. The brightness temperatures observed favour the interpretation of the bulk of the emission by thermal optically thin bremsstrahlung. The degree of polarization measured (p ≈ 0.1–0.2 in the range 7.5–15 GHz) implies quite strong magnetic fields of about ≥300 ± 100 G at a height z > 3 × l04km above the photosphere and indicates a possible contribution of gyromagnetic radiation and/or optically thick bremsstrahlung at longer wavelengths.
Published: 1989
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50. Microwave limb sources and their relation to solar flares

Author: S. Urpo, Silja Pohjolainen, V. Ruzdjak, B. Rompolt, Bojan Vršnak, and H. Teräsranta
Subjects: Physics, Atmospheric Science, Photosphere, Solar flare, Aerospace Engineering, Astronomy, Astronomy and Astrophysics, Radiation, Solar physics, Solar prominence, law.invention, Geophysics, Space and Planetary Science, law, Brightness temperature, General Earth and Planetary Sciences, Microwave, Flare
Abstract: Solar microwave maps (at 22 and 37 GHz) performed at Metsahovi (Finland) in the period 1979–1982 have revealed about a dozen radiation sources, microwave limb sources (MW LS), located up to 50 000 km above the optical limb of the Sun (in normal conditions the sources for microwave emission are locate 2 000 – 4 000 km above the photosphere). It could be established that MW LS showed up after the occurrence of two ribbon flares situated close to the limb of the visible hemisphere or that they have been connected to flares occuring behind the limb, which was documented by the appearance of Hα post flare loop systems. The life time of the MW LS was typically about 3 hours and they have been correlated to long decay events (LDE) in X-rays. In one case the active region where the MW LS appeared was also tracked at Metsahovi and a typical gradual rise and fall event was recorded. It is proposed that the MW LS are of thermal origin and that they originate from condensed flaring loops appearing at successive higher altitudes.
Published: 1986
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