The High-Energy Particle Detector (HEPD) onboard the China Seismo-Electromagnetic Satellite (CSES-01) launched in February 2018 is a light and compact payload suitable for measuring electrons (3-100 MeV), protons (30-300 MeV), and light nuclei (up to a few hundreds of MeV) with a high energy resolution and a wide angular acceptance. The very good capabilities in particle detection and separation, together with the Sun-synchronous orbit, make HEPD well suited for galactic particles and solar modulation studies. We report here some insights on the data-analysis techniques employed for this kind of study; as a result, semiannual galactic hydrogen differential energy spectra between 40 and 250 MeV for the period between the end of the 24th and the start of the 25th solar activity cycle, are presented . Moreover, a brief discussion on the comparison with theoretical spectra obtained from the HelMod 2D Monte Carlo model is also presented.

We report on the extreme γ-ray activity from the flat spectrum radio quasar (FSRQ) PKS 1510−089 observed by the AGILE satellite in March 2009. In the same period a radio-to-optical monitoring of the source was provided by the GASP–WEBT and REM facilities. In the radio band we made use also of multi-epoch 15-GHz Very Long Baseline Array data from the MOJAVE Program to get information on the parsec-scale structure. Moreover, several Swift target of opportunity observations were triggered, adding important information on the source behaviour from optical/UV to hard X-rays. We paid particular attention to the calibration of the Swift/UVOT data to make it suitable to the blazars spectra. Simultaneous observations from radio to γ rays allowed us to study in detail the correlation among the emission variability at different frequencies and to investigate the mechanisms at work during this high activity state of the source. In the period 9–30 March 2009, AGILE detected γ-ray emission from PKS 1510−089 at a significance level of 21.5-σ with an average flux over the entire period of (311±21)×10−8 photons cm−2 s−1 for photon energies above 100 MeV, and a peak level of (702±131)×10−8 photons cm−2 s−1 on daily integration. The activity detected in γ rays occurred during a period of increasing activity from near-infrared to UV, as monitored by GASP– WEBT, REM and Swift/UVOT. A flaring episode on 26–27 March 2009 was detected from near-IR to UV, suggesting that a single mechanism is responsible for the flux enhancement observed at the end of March. By contrast, Swift/XRT observations seem to show no clear correlation of the X-ray fluxes with the optical and γ-ray ones. However, the X-ray observations show a harder photon index (Γx 1.3–1.6) with respect to most FSRQs and a hint of harder-when-brighter behaviour, indicating the possible presence of a second emission component at soft X-ray energies. Moreover, the broad band spectrum from radio-to-UV confirmed the evidence of thermal features in the optical/UV spectrum of PKS 1510−089 also during high γ-ray state. On the other hand, during 25–26 March 2009 a flat spectrum in the optical/UV energy band was observed, suggesting an important contribution of the synchrotron emission in this part of the spectrum during the brightest γ-ray flare, therefore a significant shift of the synchrotron peak.

O. Adriani, G. C. Barbarino, G.A. Bazilevskaya, R. Bellotti, M. Boezio, E. A. Bogomolov, L. Bonechi, M. Bongi, V. Bonvicini, S. Borisov, S. Bottai, A. Bruno, F. Cafagna, D. Campana, R. Carbone, P. Carlson, M. Casolino, G. Castellini, L. Consiglio, M. P. De Pascale, C. De Santis, N. De Simone, V. Di Felice, A.M. Galper, W. Gillard, L. Grishantseva, P. Hofverberg, G. Jerse, A.V. Karelin, S. V. Koldashov, S. Y. Krutkov, A.N. Kvashnin, A. Leonov, V. Malvezzi, L. Marcelli, A. G. Mayorov, W. Menn, V.V. Mikhailov, E. Mocchiutti, A. Monaco, N. Mori, N. Nikonov, G. Osteria, P. Papini, M. Pearce, P. Picozza, C. Pizzolotto, M. Ricci, S. B. Ricciarini, L. Rossetto, M. Simon, R. Sparvoli, P. Spillantini, Y. I. Stozhkov, A. Vacchi, E. Vannuccini, G. Vasilyev, S. A. Voronov, J. Wu,* Y. T. Yurkin, G. Zampa, N. Zampa, and V.G. Zverev University of Florence, Department of Physics, I-50019 Sesto Fiorentino, Florence, Italy INFN, Sezione di Firenze, I-50019 Sesto Fiorentino, Florence, Italy University of Naples ‘‘Federico II’’, Department of Physics, I-80126 Naples, Italy INFN, Sezione di Napoli, I-80126 Naples, Italy Lebedev Physical Institute, RU-119991 Moscow, Russia University of Bari, Department of Physics, I-70126 Bari, Italy INFN, Sezione di Bari, I-70126 Bari, Italy INFN, Sezione di Trieste, I-34149 Trieste, Italy Ioffe Physical Technical Institute, RU-194021 St. Petersburg, Russia INFN, Sezione di Roma ‘‘Tor Vergata’’, I-00133 Rome, Italy University of Rome ‘‘Tor Vergata’’, Department of Physics, I-00133 Rome, Italy Moscow Engineering and Physics Institute, RU-11540 Moscow, Russia KTH, Department of Physics, and the Oskar Klein Centre for Cosmoparticle Physics, AlbaNova University Centre, SE-10691 Stockholm, Sweden IFAC, I-50019 Sesto Fiorentino, Florence, Italy University of Trieste, Department of Physics, I-34147 Trieste, Italy Universität Siegen, Department of Physics, D-57068 Siegen, Germany INFN, Laboratori Nazionali di Frascati, Via Enrico Fermi 40, I-00044 Frascati, Italy (Received 3 June 2010; published 13 September 2010)

We report on a new measurement of the = ratio at small atmospheric depth in the momentum range 0.3-20 GeV/ c using the NMSU-WIZARD/CAPRICE98 balloon-borne magnetic spectrometer. The flight took place on 28-29 May 1998 from Ft. Sumner, New Mexico. In the momentum range 0.3-1 GeV/ c th ratio is 1:29 0:08, lower than the corresponding ratio measured in 1994 at Lynn Lake, Canada, which was 1:59 0:06. The difference is attributed to the difference in latitude of the two experiments. For the range 2-20 GeV/ c we report a value of the ratio of 1:4 0:1.

SummaryAmong the several existent proposals for the cosmic antimatter search, the Wi#x005A-0304;ard project for the U.S. Space Station Freedom shows the greatest interest. A possible upgrading of the Wi#x005A-0304;ard apparatus, called Wi#x005A-0304;ard 2, is presented in order to sensibly improve the capability of detecting antihelium nuclei in the cosmic radiation.RiassuntoFra tutte le varie proposte esistenti nell’ambito della ricerca di antimateria cosmica, il progetto Wi#x005A-0304;ard per la Stazione Spaziale americana Freedom si dimostra del piú grande interesse. Si presenta un possibile ampliamento dell’apparato Wi#x005A-0304;ard allo scopo di migliorare sensibilmente la capacità di rivelare nuclei di antielio nella radiazione cosmica.