Cosmic Ray flux modulation in different timescales observed with the CARPET detector between 2006 and 2012 (CASLEO, 2550 m, Rc = 9.65 GV) J.-P. Raulin, V.S. Makhmutov, R.R.S. De Mendonca, E. Echer, G. Fernandez, A. Marun, R. Godoy, E. Correia, P. Kaufmann, Y.I. Stozhkov CRAAM/EE/UPM – São Paulo, Brazil LPI – Moscow, Russia INPE – SJC, Brazil CASLEO – San Juan, Argentina

SST – Solar Submillimeter Telescope Polarimeters 45 – 90 GHz IR (10  m) – 30 THz Cosmic Rays Detector CARPET EFM – Electric Field Monitor Optical Observatory Bedrooms Restaurant Staff Room VLF - Very Low Frequency SAVNET CASLEO, SAN JUAN, ARGENTINA, 2550 m, Rc ~ 9.65 GV

Differential Energy spectra of CR secondaries p, e -, e +, µ +, µ - and  at atmospheric depth X=800 g·cm -2 1,E-13 1,E-11 1,E-09 1,E-07 1,E-05 1,E-03 1,E-01 1,E+001,E+011,E+021,E+031,E+041,E+051,E+06 E, MeV I(E), #/cm2*s*MeV p  e e + Muons (+,-) UNIVAP, São José dos Campos, SP >Ee (UP,LOW) >Ep >Eµ 23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012 UP, LOW : e> 0,2 MeV, p> 5 MeV,  >0,02 MeV TEL: e> 5 Mev, p > 30 MeV

Barometric Coefficient:  ~ -0.44%/hPa Atmospheric Pressure and Temperature (see SH 611 for more details) 23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012

Preci. (mm) 30% of CARPET increase events do not present association with precipitated rain water NO RAIN 3 hours 4 hours 11 % 13 % Short-term modulation Atmospheric phenomena (see SH 612 for details) 23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012

Preci. (mm) Short-term modulation Atmospheric phenomena 30% of CARPET increase events do not present association with precipitated rain water 23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012

All RC increase events (LOW, UP and TEL) are associated with atmospheric electric field variations. RC increase events (LOW, UP) can be observed in association with rain precipitation. UNIVAP, São José dos Campos, SP Short-term modulation Atmospheric phenomena Since EFM measurements, all CARPET events (100 % on > 200 events ) are associated with electric field variations. Acceleration of secondaries by electric field. See SH rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012

Date (UT) Decrease in CARPET (%) 2006/04/20 11:124,6 2006/07/27 13:533,0 2007/04/09 04:427,6 2007/05/21 23:206,1 2007/06/21 09:314,4 2007/10/25 11:356,2 2007/11/19 18:114,6 2008/08/08 23:446,2 2008/11/24 23:514,6 2009/05/28 05:191,6 2010/04/05 08:264,8 2010/05/02 09:083,0 In addition to CR variations due to atmospheric effects (rain precipitation, electric field), and on longer timescales due to the solar activity cycle, the CARPET detected ~ 12 Forbush decreases, ranging from ~ %. CARPET also detected CR variations during solar flares 23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012 CARPET

neutrones ? NOAA / N23 W59 19:43 – 20:12 – 20:58 XRA 1-8 M

2030 – 2040 UT 23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012

6/03/ MARCH MARCH

7 - MARCH , time UT 23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012

23- JAN N28W20 / AR UT, M8.7 23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012

PAMELA did also observe this event

Summary I The CARPET device has been monitoring the flux of secondary charged particles and over 75 months since April So far we have found CR flux modulations on different timescales: - Counts are corrected for atmospheric P and T variations (see poster SH 611). - long-term modulation well associated with the actual solar cycle variations. - modulation (2 - 8 %) of count rates during ~ 12 Forbush decrease events. - short-term (few hours) modulation (≤ 20 %) CARPET events (> 250): * 70% associated with precipitation of rain water * 30% occurred without any rain * since EFM measurements, all CARPET events are associated with electric field variations (see poster SH 612) 23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012

Summary II As a preliminary result of the analysis of the CARPET cosmic ray detector records, VLF and Radiometer network measurements (NCAE, NPL, ROI) on March, 2011 and January, 2012, we conclude (see posters SH-560 and SH-563): (1) statistically significant long-lasting increases were detected during 7-8 March 2011 and 23, 27 January 2012 solar flare events. (2) these increases are indication of long-lasting high-energy solar protons (E > 9 GeV) entering the Earth`s atmosphere. (3) for the 27 th January 2012 event both gradual long-lasting and fast varying submm-activity are detected within the period of CARPET increase. Finally, we note that a more careful analysis of the NMDB records is needed in order to get a final conclusion on the presence or not of solar flare effects in the form of GLEs during these events. 23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012

NEW CARPET RESULT at Rc =9.65 GV

Cosmic ray monthly averaged intensity in the maximum of depth intensity profile in the stratosphere (Murmansk region, thick line) and as observed by the Moscow neutron monitor (thin line). The data are normalized at the average value for N+ S+ MURMANSK NM MOSCOW

High Energy Processes in the Sun, Interplanetary Space and their Effects in the Earth Atmosphere (FAPESP: 2011/ )‏ Project Summary: This project is aimed to study the physical mechanisms of high-energy releases taking place in solar quiet and explosive active regions, and their signatures in the Earth's atmosphere. To do so we need sensitive instruments which could provide us with a diagnostic of these processes. Part of these instrumental facilities already exist and are being successfully operated at CASLEO, San Juan, Argentina. The heliogeophysical laboratory at CASLEO provide us with diagnostic of solar flares at millimeter waves (45 and 90 GHZ), submillimeter (212 and 405 GHz), IR (30 THz), as well as with diagnostic of the flare X-ray radiation imprints in the ionosphere (VLF subionospheric propagation), and of energetic charged particles in Earth's atmosphere (Cosmic Ray CARPET sensor). We propose to complement these facilities with a new detector of solar and atmospheric neutrons, a γ - ray scintillation device, and ELF/VLF wave sensors. The main objectives are: (i) to better characterize the high-frequency radio and high-energy photon flare spectra, in order to provide new clues on the emission mechanism resulting in submillimeter and THz radiation which are still unexplained; (ii) to provide a continuous monitoring of solar energetic phenomena and investigate if they are more frequent than what we do observe nowadays; (iii) to investigate the causal relationship between atmospheric phenomena as lightning occurrence, high-energy photon and neutron production, Terrestrial Gamma-ray Flashes, and cosmic ray fluxes. Participants and Partners: CRAAM/EE/UPM(São Paulo/Brazil), LPI (Moscow/Russia), IAG/USP (São Paulo/Brazil), CASLEO (San Juan/Argentina), CONIDA(Lima/Peru)‏

UNIVAP, São José dos Campos, SP