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Observation of galactic cosmic ray spallation events from the SoHO mission 20-yr operation of LASCO

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Observation of galactic cosmic ray spallation events from the SoHO mission 20-yr operation of LASCO

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A shower of secondary cosmic ray (CR) particles is produced at high altitudes in the Earth's atmosphere, so the primordial galactic cosmic rays (GCRs) are never directly measured outside the Earth magnetosphere and atmosphere. They approach the Earth and other planets in the complex pattern of rigidity's dependence, generally excluded by the magnetosphere. GCRs revealed by images of single nuclear reactions also called spallation events are described here. Such an event was seen on 2015 November 29 using a unique Large Angle and Spectrometric Coronagraphs C3 space coronagraph routine image taken during the Solar and Heliospheric Observatory (SoHO) mission observing uninterruptedly at the Lagrangian L1 point. The spallation signature of a GCR identified well outside the Earth's magnetosphere is obtained for the first time. The resulting image includes different diverging linear 'tracks' of varying intensity, leading to a single pixel; this frame identifies the site on the silicon CCD chip of the coronagraph camera. There was no solar flare reported at that time, nor coronal mass ejection and no evidence of optical debris around the spacecraft. More examples of smaller CR events have been discovered through the 20 yr of continuous observations from SoHO. This is the first spallation event from a CR, recorded outside the Earth's magnetosphere. We evaluate the probable energy of these events suggesting a plausible galactic source.
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Observation of galactic cosmic ray spallation events from the SoHO
mission 20-Year operation of LASCO
S. Koutchmy 1?, E. Tavabi1,2& O. Urtado1
1Institut d’Astrophysique de Paris, UMR 7095, Sorbonne Université- CNRS and UPMC, 98 Bis Bd. Arago, 75014 Paris, France.
2Physics Department, Payame Noor University (PNU), 19395-3697, Tehran, I. R. of Iran.
Accepted XXX. Received YYY; in original form ZZZ
ABSTRACT
A shower of secondary Cosmic Ray (CR) particles is produced at high altitudes in the Earth’s
atmosphere, so the primordial Galactic Cosmic Rays (GCRs) are never directly measured
outside the Earth magnetosphere and atmosphere. They approach the Earth and other planets
in the complex pattern of rigidity’s dependence, generally excluded by the magnetosphere.
GCRs revealed by images of single nuclear reactions also called spallation events are described
here. Such an event was seen on Nov. 29, 2015 using a unique LASCO C3 space coronagraph
routine image taken during the Solar and Heliospheric Observatory (SoHO) mission observing
uninterruptedly at the Lagrangian L1 point. The spallation signature of a GCR identified well
outside the Earth’s magnetosphere is obtained for the 1s t time. The resulting image includes
different diverging linear "tracks" of varying intensity, leading to a single pixel; this frame
identifies the site on the silicon CCD chip of the coronagraph camera. There was no solar flare
reported at that time, nor Coronal Mass Ejection (CME) and no evidence of optical debris
around the spacecraft. More examples of smaller CR events have been discovered through the
20 years of continuous observations from SoHO. This is the first spallation event from a CR,
recorded outside the Earth’s magnetosphere. We evaluate the probable energy of these events
suggesting a plausible galactic source.
Key words: Sun: Galactic Cosmic Rays, Solar Energetic Particles, Heliosphere.
1 INTRODUCTION
The CCD imaging instruments of the SoHO mission (Domingo
et al. 1995) of ESA and NASA, including the Large Angle and
Spectrometric Coronagraphs (LASCO) and the Extreme ultravio-
let Imaging Telescope (EIT) imagers, are sensitive to Solar Ener-
getic Particles (SEP) in the MeV up to GeV range. Yagoda (1962),
Obayashi (1964) and Roederer (1964) reported that a myriad of
impacts is continually recorded at the time of big flares and CMEs.
Higher energy particles in the GeV and in the more energetic range
up to 1021eV are today called cosmic rays (CR), e.g., see Freier et
al. (1948); Chandrasekhar and Fermi (1953); Fermi (1954); Gaisser
(1990) and Dorman (2006), they are primarily made of protons.
Usually remotely registered at ground-based (G-B) observatories
by different methods, following their interaction in the upper atmo-
sphere, at a column depth of order 1033 g
cm2(Kudela 2009). They
produce a shower of secondary particles as a result of a sequence
of reactions of the primary CR particle. In G-B observations they
are also registered in situ with the neutron monitors preferably at
high altitude sites to be closer to the primary site of CRs interaction
with the Earth atmosphere but G-B observations exist at sea level
?E-mail: koutchmy@iap.fr
including the large facilities developed for analyzing the very high
energies (Smart and Shea 2009).
The primary particles have been deflected by the galactic magnetic
field making their trajectory in the interstellar space impossible to
follow (Baade and Zwicky 1934;Butt 2009). These particles are
then deviated in the much stronger magnetic field of the heliosphere
and finally by the magnetic field of our magnetosphere (Dorman
2006;Kahler 1992;Smart and Shea 2009;Miroshnichenko 2015),
as illustrated in Fig. 1. Known and studied for one century and
despite the existence of a very extended scientific literature, the
definite origin of these particles is still not established because of
the difficulty to identify the source(s) in the sky and to theorize
the mechanisms for producing such extreme energies. The popular
and classical suggested scenario is the so-called Fermi mechanism
(Chandrasekhar and Fermi 1953;Fermi 1954) of acceleration of el-
ementary particles in the magnetized shock front of the super-novae
explosions occurring in our galaxy, including the remnants. Neutron
star activity, super-flares on O-type massive stars and other exotic
stellar phenomena are today also considered. Even more extremely
energetic CRs are seldom registered and new sources related to
black hole "activity" are suggested from our own galactic center
and more probably, from extra-galactic objects (Butt 2009). A very
popular and well-established quantitative parameter of CR is shown
©2017 The Authors
2S. Koutchmy, E. Tavabi & O. Urtado
Figure 1. Synoptic view of the heliosphere and magnetosphere with magnetic structures, schematically showing the position of the SoHO spacecraft with
energetic particles of different origins coming in (frames from movies by NASA and ESA are used to consider this synoptic image).
by the display of their energy spectrum which shows the flux of CR
versus the energy of the particles as a quasi- power law (Kudela
2009) for the parts corresponding to energies E>1GeV. From this
brief presentation it is clear that any new diagnostic of galactic CRs
will be welcome especially from observations made in space well
outside our magnetosphere. This has been possible thanks to unin-
terrupted observations performed by the SoHO spacecraft launched
on 1995 Dec. 02 and still in operation today as far as the coronal
imaging experiment is concerned. The spacecraft is put in a halo
orbit of the Lagrangian L1 point situated roughly 0.01 AU interior
to the orbit of the Earth system, see Fig. 1.
Since they are not shielded by the Earth’s magnetosphere,
SoHO suffered damage from CRs (Curdt and Fleck 2015), starting
with the solar array degradation and the solid state recorder system.
From an analysis of the upsets in the recorder system for solar cycle
23 (1996 to 2008) it was found (Curdt and Fleck 2015) that 94%
of effects were due to CR of galactic origin (GCRs). However the
Forbush effect as known for a long time from the neutron monitor
recording (Simpson 1957;Lara et al. 2005) was not observed by
Curdt and Fleck. Still SoHO imaging experiments using a CCD
chip as a detector produced a myriad of dots and tracks on LASCO
coronal images (Domingo et al. 1995) and many movies show-
ing the "snowstorm" effect produced by Solar Energetic Particles
(SEPs) resulting from major flares and from large-scale Coronal
Mass Ejections CMEs (e.g. Cane et al. 2010;Kahler 1992) see Fig.
2. We concentrate here on images coming from the C3 externally
occulted coronagraph (Brueckner et al. 1995) that produces a 16o
large field-of-view (FOV) around the Sun. Images show i) the solar
corona plasma structure; ii) the large halo of the dusty F-corona
surrounding the Sun (Koutchmy and Lamy 1985); iii) bright stars,
sun-grazing comets and planets crossing the FOV; iv) images of
space debris; v) bright dots and linear tracks mainly produced by
SEPs and presumably, by GCRs more easy to record when the Sun
is quiet.
2 OBSERVATIONS
Fig. 1presents a synoptic view of the solar system showing the
spacecraft SoHO with the different components identified. Note
that space debris produce rather out of focus optical effects over
the optical FOV. They are affected by the internal vigneting and
masking, including the effect of the external occulters; images of
their tracks correspond to extended objects moving rapidly across
the FOV easy to identify. This is in contrast with the effects of SEP
and CRs that produce pixel-width signature (bright dots and tracks)
over the 20 ×20 mm2chip of the CCD camera, everywhere over its
surface including the part optically masked by the external occulter.
This well-known effect is prominent at the time of big X-type flares
on the Sun and it is easily evaluated from the processed images and
movies produced by the SoHO’s LASCO experiment and stored in
different data bases at NASA, ESA and the participating labs, see
Fig. 2. We refer to observations of the classical and best studied
X 5.7 flare event of July, 14, 2000 (Bastille day flare) to extract
some relevant specifications of the event with respect to CRs (Klein
et al. 2001;Belov et al. 2001;Mishev and Usoskin 2016). Note
that the flare produced (Lara et al. 2005) a definite Ground Level
Enhancement (GLE) # 59 in Neutron Monitors (NMs). CRs of
energies up to 6 GeV are reported from Neutron Monitors recording
(Belov et al. 2001). The occurrence of millions of point-like impacts
with a few tracks after a solar flare is an impor tant feature of the CCD
images that permits a definite identification of the tracks produced
MNRAS 000,18(2017)
Observation of galactic cosmic ray spallation events from the SoHO mission 20-Year operation of LASCO 3
Figure 2. Bastille day extreme solar flare (10:30 U.T., 14t h July 2000) of active region 9077 to show (a & b) the effect of energetic particles recorded inside
the CCD chip using the LASCO imaging instrumentation of the SoHO spacecraft observing the Sun from the L1 Lagrangian point. The event corresponds to a
massive X-type flare as demonstrated by the sudden increase of GOES8 proton flux (c) and the GOES X-ray flux (d).
by the ionization effect of a SEP inside the Si plate of thickness of
order of 60 microns.
Images also show near the surface of the Sun million degrees hot
solar plasma cooling down while suspended in an arcade of post-
flare magnetic loops. SEPs have different origins. Primary SEP are
produced in the reconnection region of the flare itself at the solar
surface with impulsive events. Even more significant secondary SEP
are produced as the result of interaction with the ejected shock front
of the CMEs (gradual events, Klein et al. 2001;Curdt and Fleck
2015;Firoz et al. 2011). For the sake of simplicity planets and
bright streaks due to debris are not shown as Fig. 1although they
are well recorded by the LASCO coronagraphs. The trajectory of a
GCR penetrating inside the solar system is shown at left with a red
color: it is shown exaggeratedly being deviated by the heliospheric
magnetic-field before reaching the spacecraft (not to scale). Tracks
are produced when the trajectory of the particle is close to parallel
to the surface of the CCD. We note that the cross section of the
nucleus of the silicon atoms is similar to the cross section for Al and
other metallic components of the spacecraft; it makes a convenient
detector of energetic CRs chip in case of a collision inside the
chip. Such interactions also appear at times of low or no solar
activity (no trace of flaring active region on the disk, no GOES soft
X-ray signatures) and no CME event. The GCRs usually produce a
signature not different from the dot or line signatures given by SEPs.
Their energy (Kudela 2009) is distributed according to a power law
function which is well established from decade long observation
at ground, after spallation nuclear reactions with the high Earth
atmosphere atoms. In the example of the 2000 Bastille day extreme
large event, we tried, without success, to look at the more complex
signature as the "star" image described by Levi Setti and Tomasini
(1952), in LASCO images, especially frames taken after the X-
ray flare when the most energetic protons hit the CCD chip. We
repeated the search, again without success, for the recent "double"
X-type flare of Sept. 6 (disk event) and of Sept. 9 (limb event),
2017 using both the sequences from the C2 and the C3 LASCO
coronagraphs of SoHO. At presumably higher energy (see Fig. 3),
a spallation event see e.g. Kowalczyk (2008) and Krasa (2010)
and pictures of what was called "star" from the former appearance
in photographic plates (Levi Setti and Tomasini 1952) may indeed
result in a photographic emulsion, see Yagoda (1962). This is exactly
what was noticed during an examination of a movie made from
routinely processed C3/LASCO coronagraph observations of the
MNRAS 000,18(2017)
4S. Koutchmy, E. Tavabi & O. Urtado
Figure 3. The original frame of the C3 coronagraph of LASCO (SoHO mission) taken at 11:30 UT on 29 Nov. 2015 at time of a quiet Sun with an over-
exposed image of the planet Mercury in the FOV. (a) Evidence of a spallation event shown at the bottom of the frame; reminding the first "stars" images from
of galactic CR event recorded in balloon experiments (Levi Setti and Tomasini 1952). Note in panel a the dominating halo of the F-corona usually removed
in routine images to enhance the K-corona variable structures; (b) the recording of the X-ray very low flux level radiation from the Sun given by the GOES
satellite at the time of the observation, before and after; (c) schematic of the spallation event recorded inside the CCD chip following a collision by a high
energy CR. The tracks of secondary particles produced at large angles will cross the chip and a small part will leave excited electrons that are subsequently
read when the optical image is recorded. The tracks are not limited by the field of optical observations nor the external mask (d) the partial frame magnified in
negative to show the region of the impact.
SoHO mission, at 11:30 UTC of 29 Nov. 2015, a time of very low
solar activity on the Sun. Here we show the original level 1 image to
identify the whole event, including the part of the image outside the
computer generated mask that usually is not shown on the processed
images.
3 RESULTS
The important discovery-image is presented in Fig. 3. We note that
the original image shows the tracks with a lower contrast than the
routine processed image where several stationary components are
accurately subtracted (after calibration), including the dominating
F-corona (Koutchmy and Lamy 1985) in order to show the vari-
able in time coronal structure (K-corona). In the bottom panel c)
of Fig. 3we show a contrast enhanced and magnified partial im-
age. The linear features were enhanced using the Madmax operator
(Koutchmy and Koutchmy 1989;Marshall et al. 2006;Tavabi et al.
2013) in the hope of finding the direction of the primary CR particle
without great success. The panel b) of Fig. 3presents a possibly
realistic schematic with a suggested scenario, where tracks could
be produced inside the thin chip. This remarkable image, recorded
in space, outside the Earth’s magnetosphere, induced considerable
discussion among the SoHO community concerned with the inter-
pretation of C3 and C2 coronagraph images. After a quick-look
analysis of LASCO images for several years (see Figs. 4and 5) it
appears that this event was probably the most energetic event ob-
served for the more than 20 years of the SoHO mission, possibly
a spallation event following a collision. Using the well-established
power law of the spectral energy distribution of CRs observed on
the ground (Freier et al. 1948;Dorman 2006;Kudela 2009), it is
attempted to evaluate the range of maximum energy of CRs that will
hit once the 400 mm2surface. We found the chip is of a 60 micron
effective thickness in the LASCO camera and we follow the anal-
ysis performed in laboratories (e.g. Kowalczyk 2008;Putze 2009).
Assuming a normal angle of arrival and a duration of 10 years and a
maximum probability for the particle interacting at least once with
a nucleus of Si of the chip during the crossing of the detector, our
particle is found in the range of the 1013 to 1014 eV. Particles of
this energy are considered to be produced within our Galaxy and
are called GCRs.
This 1st evaluation is however not realistic because of the assump-
tion of a signature every time the particle hits the chip. The equiv-
MNRAS 000,18(2017)
Observation of galactic cosmic ray spallation events from the SoHO mission 20-Year operation of LASCO 5
Figure 4. Example of different type of spallation events detected on single frames from the SoHO W-L coronagraphs database: a) linear tracks suggesting
an impact with small pitch angle; note the part of a track seen only outside the optical FOV of the instrument (on the direction of the top red arrows); b)
impact producing secondary particles inside the chip with large pitch angle; c) single thicker track suggesting heavier particles propagating inside the chip and
producing some "ionization" effect around their track.
alent nuclear cross section of the Si chip or equivalently, the mean
free path of a particle crossing the silicon detector should be con-
sidered. We compared our detector sensitivity with what exists in
the Earth’s atmosphere (the nuclei of Oxygen and of Nitrogen are
concerned) and use the measured proton-air inelastic cross-section
measured by accelerators and cosmic-ray experiments for the range
of energies between 109and 1013 eV from the Belov (2013) Fig. 2.
The value is typically 280 to 300 mb or 0.3×1028 m2for energies
in the range of 109to 1013 eV. Further, the effective radius of the
nucleus is 105times the radius of the Si atom which is of order of
5Û
Aor 0.5×109m. For a proton it is 0.84 ×1015 m or 0.84 fm.
The nucleus of Si is made of 14 protons and 14 neutrons. Note the
cubic cell structure of the atom of Si with dimension 5.43 Û
A. The
corresponding mean free path for a proton will be of order of 10 m.
MNRAS 000,18(2017)
6S. Koutchmy, E. Tavabi & O. Urtado
Figure 5. C2 & C3 selected spallation events recorded during the SoHO mission (1996 to 2017). Frames correspond to processed images after removing the
stationary background as done at NRL. It is possible that this procedure favors the detection of the larger FOV observations taken with the C3 coronagraph
(blue frames) compared to the C2 coronagraph images (red frames). Days with significant flares and/or CMEs on the Sun are carefully avoided.
Using these approximations we finally got a probable occurrence
of a nuclear collision producing a spallation event in our chip of
20 ×20 mm2and 6×105m thickness for a period of 10 years
when the flux is very close to 1 par t./sec/m2. The correspond-
ing energy is then 1011 eV or 100 GeV which is definitely above
what is measured at most for a solar CR (Miroshnichenko 2015),
confirming our assumption of an event of GCR origin.
4 DISCUSSION AND CONCLUSIONS
Let us discuss several, presumably lower energy similar cases or
cases not corresponding to a central collision that we found after
using the whole set of LASCO (SoHO mission) coronagraph images
from both C3 and C2 instruments. Fig. 4presents 5 different types
of events found in sequences recorded in 2010-2017. It gives a better
perspective of effects (tracks) produced inside the chip by different
CRs energies or different type of collisions. The most abundant CRs
are made of protons but alpha particles (H e++ ) and heavier nuclei
could also hit the chip (Schimmerling et al. 1996;Kudela 2009). In
Fig. 5we show selected events made from single processed frames
found among the thousands sequences of full day coronagraphic
observations, avoiding the case of SEPs at the same time as flares
or CMEs. Note that all cases that we picked up show a single event
with several related tracks, short and/or long. Again the case of
Nov. 29, 2015 discussed above shows the best case showing both
the location of the collision as a 2 px size "very bright point" with the
secondary particles producing several divergent tracks of different
length depending of the angle of their real tracks with respect to
the plane of the chip, see Fig. 2. From a simple probabilistic
evaluation, after evaluating the typical number of CR dots/frame
taken at 12 minute cadence during periods outside solar activity
events, we deduce an average maximum energy >1 TeV for particles
responsible for the dots-events. However, an independent evaluation
of the most probable value of energy of our best observed event of 29
Nov. 2015 (see Fig. 3) points to a range of energies of about 1011 eV.
In addition, we do not have a comparable "star" signature for SEPs
(Ramaty et al. 1996) occurring at the time of a big flare producing a
large halo CME. We suggest that our events are of galactic origin of
the most energetic particles that we record using the CCD imaging
techniques and point out the consequences of this discovery made
MNRAS 000,18(2017)
Observation of galactic cosmic ray spallation events from the SoHO mission 20-Year operation of LASCO 7
quite far from Earth. The origin of the GCR particles is not known.
We also tentatively looked at the temporal variations of the number
of events observed at a one-month resolution. We note a strong
variation in time depending of the level of the solar activity. This
is well known from G-B observations and the so-called Forbush
effect (Kudela 2009). The expulsion of solar magnetic clouds related
to CMEs (Lara et al. 2005) and the quasi- stationary co-rotating
interplanetary magnetic sectors deflect GCRs (see Fig. 1). This is
also a part of the SEP variations that we avoid when counting the
GCRs. It possibly produces some bias, partly explaining why we
see a solar cycle variation much larger (a factor of 2 instead of 30%)
than what we see on the ground.
Note that our data are taken well outside the Earth’s magnetosphere
significantly deflects SEPs and GCRs; it makes the records in G-
B data more affected. Accordingly, there is a suspicion that the
modulation produced by solar activity on GCRs could be larger than
what is usually given. Further we looked at the yearly modulation
using the data for the full years 2000, 2008 and 2009. We found
indications that the number of events per month is more numerous
in December- January, at the years of minimum activity (2008 and
2009). Incidently, this is the epoch when the SoHO spacecraft, which
is always pointed towards the Sun with the CCD chip normal to that
direction, also sees the center of our Galaxy. It is now believe that
this region is made of a rotating massive black hole in Sagittarius and
recently imaged (Ackermann et al. 2013;Cardillo et al. 2014) with
Chandra. A lot of activity at the periphery is expected, including
extreme magnetic activity accelerating elementary particles to GCR
energy. Sources such as IC 443 and the Crab nebula SN remnant
on the opposite direction of the sky (Grenier et al. 2015;Michael
et al. 2016) could as well be significant. Finally, more GCRs could
be determined using the whole set of available for more than 20
years observations and after some automatic method (Koutchmy
and Koutchmy 1989;Marshall et al. 2006;Tavabi et al. 2013) of
detecting the GCRs events in LASCO images is elaborated.
ACKNOWLEDGEMENTS
The SoHO/LASCO data used here are produced by a consor-
tium of the Naval Research Laboratory, Max-Planck-Institut für
Aeronomie (Germany), Laboratoire d’Astronomie de Marseille
(France), and the University of Birmingham (UK). We are grateful
to the SOHO/LASCO team for making their data publicly available.
SoHO is a project of international cooperation between ESA and
NASA. We warmly thank Hugh Hudson (Univ. of Glasgow) who
was the first to encourage this research on CRs and who contributed
very much in the discussion of the data and the presentation of this
paper; Philippe Lamy (LAM- CNRS), Bernard Fleck (ESA), Russel
Howard (NRL), Andrei Zhukov (ROB), Sergei Kuzin (LPI), Pierre
Astier (IN2P3), Benoit Revenu (Nantes Univ), Leon Golub (SAO),
Michel Dennefeld (IAP), Nicolas Prantzos (IAP), each brought their
contribution to the discussion at different stages of the analysis.
Francois Sevre (IAP) performed some additional analysis of the
data and John Stefan (NJIT) diligently help with the manuscript;
Guillaume Boileau performed a preliminary analysis of the data at
IAP.
REFERENCES
Ackermann, M., Ajello, M., Allafort, A., et al. 2013. Detection of the Char-
acteristic Pion-Decay Signature in Supernova Remnants, Science, 339,
807-811
Baade, W. and Zwicky F., 1934. Remarks on Super-Novae and Cosmic Rays.
Physical Review 46, 76-77
Belov, A. V., Bieber, J. W., Eroshenko, E. A., Evenson, P., Pyle, R., & Yanke,
V. G. 2001, Proc. 27th Int. Cosmic-Ray Conf. (Hamburg), 9, 3507
Belov, K. 2013, Measuring chemical composition and particle cross- sec-
tion of ultra- high energy cosmic rays by a ground radio ar ray, in
arXiv:1312.0382v1
Brueckner, G. E., et al. 1995, Sol. Phys., 162, 357
Butt, Y., 2009. "Beyond the Myth of the Supernova Remnant Origin of
Cosmic Rays", Nature 460, 701-704
Cane, H. V., Richardson, I. G., & von Rosenvinge, T. T. 2010, JGR (Space
Physics), 115, A08101
Cardillo, M.; Tavani, M.; Giuliani, A., 2014. The origin of Cosmic-Rays
from SNRs: confirmations and challenges after the first direct proof,
Nuclear Physics B (Proceedings Supplements), 256, 65-73
Chandrasekhar, S., and Fermi, E., 1953. Magnetic Fields in Spiral Arms.
ApJ. 118, 113-115
Curdt, W. and Fleck, B., 2015. Solar and Galactic Cosmic rays observed by
SOHO, Cent. Eur. Astrophys. Bull. 1, 1
Domingo, V., Fleck, B., & Poland, A. I., 1995. The SOHO Mission: an
Overview. Sol. Phys., 162, 1-37
Dorman, L. ed., 2006. Cosmic Ray Interactions, Propagation, and Accel-
eration in Space Plasmas, vol. 339 of Astrophysics and Space Science
Library
Firoz, K. A., Moon, Y. -J., Cho, K. -S., Hwang, J., Park, Y. D., Kudela,
K., & Dorman, L. I., 2011. On the relationship between ground level
enhancement and solar flare J. Geophys. Res., 116, A04101
Freier, P., Lofgren, E. J., & Oppenheimer, F., 1948. The Heavy Component
of Primary Cosmic Rays, Phys. Rev., 79, 1818
Fermi, E., 1954. Galactic Magnetic Fields and the Origin of Cosmic Radia-
tion, ApJ, 119, 1-6
Gaisser, T. K., 1990. nCosmic Rays and Particle Physics , Cambridge: Cam-
bridge Univ. Press,
Grenier, I. A., Black, J. H., & Strong, A. W., 2015. The Nine Lives of Cosmic
Rays in Galaxies, ARA&A, 53, 199-246
Kahler, S. W., 1992. Solar Flares and coronal mass ejections ARA&A 30,
113K
Klein, K.-L., Trottet, G., Lantos, P., & Delaboudini‘ere, J.-P. 2001, A&A,
373, 1073
Koutchmy, S. and Lamy, P. L., 1985. Properties and Interactions of Inter-
planetary Dust, R. H. Giese & P. L. Lamy (Eds.), ASSL 119, 63
Koutchmy, O. and Koutchmy, S., 1989. Optimum filter and frame integra-
tion application to granulation pictures, in Proc. 10th Sacramento Peak
Summer Workshop, High Spatial Resolution Solar Observations, ed. O.
von der Luhe (Sunspot: NSO), 217
Kowalczyk, A. 2008, Proton induced spallation reaction in range 0.1-10
Gev, Ph.D Jagiellanian University, Cracow
Krasa, A. 2010, Spallation reaction Physics, coursec Czech Techn. Univ.
Prague
Kudela, K., 2009. On energetic particles in space. Acta Phys. Slovaca, 59,
537- 652
Marshall, S. Fletcher, L. and Hough, K., 2006. Optimal filtering of solar
images using soft morphological processing techniques, Astron. Astro-
phys. 457, 729
Lara, A., Gopalswamy, N., Caballero-Loťpez, R. A., Yashiro, S., Xie, H., &
Valdeťs-Galicia, J. F. 2005, ApJ, 625, 441
Levi Setti, R. and Tomasini, G. 1952, Slow Heavy Mesons from Cosmic
Ray Stars, Nuevo Cimento, Vol. IX, N. 12, 1242
Michael D. Delp, Jacqueline M. Charvat, Charles L. Limoli, Ruth K. Globus
& Payal G., 2016.Apollo Lunar Astronauts Show Higher Cardiovas-
cular Disease Mortality: Possible Deep Space Radiation Effects on
the Vascular Endothelium, Nature Scientific Reports, 6:29901 DOI:
10.1038/srep29901
Miroshnichenko, L. 2015, Solar Cosmic Rays, Astrophys. And Sp. Sc. Li-
brary, 405, DOI 10.1007/978-3-319-09429-8
Mishev, A.; Usoskin, I. 2016, Solar Physics, 291, 1579-1580
Obayashi T., 1964. The Streaming of Solar Flare Particles and Plasma in
Interplanetary Space, Space Science Reviews, 3, Issue 1, 79-108
MNRAS 000,18(2017)
8S. Koutchmy, E. Tavabi & O. Urtado
Antje Putze. Phénoménologie et détection du rayonnement cosmique nu-
cléaire. Cosmologie et astrophysique extra-galactique [astro-ph.CO].
Université Joseph-Fourier - Grenoble I, 2009. Français.
Roederer, J. G., 1964.Generation, Propagation and Detection of Relativistic
Solar Particles, Space Science 3, Issue 4,487-511
Ramaty, R., Mandzhavidze N., & Kozlovsky, B., 1996. in AIP Conf. Proc.
374, High Energy Solar Physics, ed. R. Ramaty, N. Mandzhavidze, &
X.-M. Hua (New York: AIP), 172-180
Simpson, J.A., 1957. Cosmic Radiation Neutron Intensity Monitor. Annals
of IGY IV, Pergamon Press, London p. 351
Schimmerling, W., J. W. Wilson, J. E. Nealy, S. A. Thibeault, F. A. Cucinotta,
J. L. Schinn, M. Kim, and R. Kiefer, 1996. Shielding against Galactic
cosmic rays, Adv. Sp. Res., 17, (2)31-(2)36
Smart, D. F. and Shea M. A., 2009. Fifty years of progress in geomagnetic
cutoff rigidity determinations, Adv. Space Res. 44, 1107-1123,
Tavabi E., Koutchmy S., Ajabshirizadeh A., 2013. Increasing the Fine Struc-
ture Visibility of the Hinode SOT Ca II H Filtergrams, Sol. Phys.
283,187
Yagoda H., 1962. Radiation Studies in Space with Nuclear Emulsion Detec-
tors, Space Science Reviews, 1, 224-277
This paper has been typeset from a T
E
X/L
A
T
E
X file prepared by the author.
MNRAS 000,18(2017)
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