Transcript Slide 1

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
CASLEO, SAN JUAN, ARGENTINA, 2550 m, Rc ~ 9.65 GV
• VLF - Very Low Frequency
SAVNET
• SST – Solar Submillimeter Telescope
• Polarimeters 45 – 90 GHz
• IR (10 m) – 30 THz
• Cosmic Rays Detector CARPET
• EFM – Electric Field Monitor
Bedrooms
Restaurant
Staff Room
Optical Observatory
Differential Energy spectra of CR secondaries p, e-, e+, µ +,
µ- and  at atmospheric depth X=800 g·cm-2
UP, LOW : e> 0,2 MeV, p> 5 MeV , >0,02 MeV TEL: e> 5 Mev, p > 30 MeV
1,E-01

I(E), #/cm2*s*MeV
1,E-03
e
+
e
1,E-05
p
1,E-07
>Ep
Muons (+,-)
1,E-09
>Eµ
1,E-11
>Ee (UP,LOW)
E, MeV
>Ep
1,E-13
1,E-01
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1,E+00
1,E+01
1,E+02
1,E+03
UNIVAP, São José dos Campos, SP
1,E+04
1,E+05
1,E+06
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23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012
Atmospheric Pressure and Temperature
(see SH 611 for more details)
Barometric Coefficient:  ~ -0.44%/hPa
F
 I 
     h T h dh   T (hG )
 I T hI
h
23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012
Short-term modulation Atmospheric phenomena
(see SH 612 for details)
Preci. (mm)
11 %
13 %
Preci. (mm)
4 hours
Preci. (mm)
3 hours
Preci. (mm)
NO RAIN
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
Short-term modulation Atmospheric phenomena
Preci. (mm)
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
Short-term modulation Atmospheric phenomena
RC increase events (LOW, UP) can be
All RC increase events (LOW, UP and TEL)
Since
EFM measurements,
% on
> 200 events
) are associated
observed
in
associationall CARPET
with
rainevents (100are
associated
with atmospheric
electric
precipitation.
field
variations.
with electric field variations. Acceleration of secondaries by electric field. See SH 612
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23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012
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 ~ 2 - 8 % .
Date (UT)
Decrease in CARPET (%)
2006/04/20 11:12
4,6
2006/07/27 13:53
3,0
2007/04/09 04:42
7,6
2007/05/21 23:20
6,1
2007/06/21 09:31
4,4
2007/10/25 11:35
6,2
2007/11/19 18:11
4,6
2008/08/08 23:44
6,2
2008/11/24 23:51
4,6
2009/05/28 05:19
1,6
2010/04/05 08:26
4,8
2010/05/02 09:08
3,0
CARPET
CARPET also detected CR variations during solar flares
23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012
neutrones ?
NOAA 11164 / N23 W59
19:43 – 20:12 – 20:58 XRA 1-8 M3.7 11164
2030 – 2040 UT
23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012
7 MARCH 2011
8 MARCH
7 - MARCH - 2011, time UT
23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012
23- JAN - 2012
N28W20 /
AR 11402
0338-0359-0434 UT, M8.7
23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012
PAMELA did also observe this event
23rd European Cosmic Ray Symposium and 32nd RCRC, MSU, Moscow – 3-7 July, 2012
Summary I
The CARPET device has been monitoring the flux of secondary
charged particles and over 75 months since April 2006. 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 27th 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
NM MOSCOW
MURMANSK
S+
N+
N+
S+
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 1965.
High Energy Processes in the Sun,
Interplanetary Space and their Effects
in the Earth Atmosphere
(FAPESP: 2011/24117-9)
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 γray 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)
GEANT4 simulation
E=0.4 kV/cm (40 kV/m)
100000
10000
Ee, keV
1000
100
10
1
0,1
1
10
100
1000
10000
100000
Track _ Length (cm)
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