solar neutrons in the pamela experiment 2006-2012€¦ · sf2011-2012 and dec.2006. search of solar...
TRANSCRIPT
Solar Neutrons in the PAMELA Experiment 2006-2012
E.A. Bogomolov, S.Yu. Krut’kov, G.I. Vasilyev Ioffe
Physical-Technical Institute
6th PAMELA Collaboration Meeting26-28 November 2012, Udine, Italy
A little of Solar Neutrons History1.
SF 21 June 1980, Gamma Ray Spectrometer aboard Solar Maximum Mission, En
~100 MeV, Chupp
et al. 1982
2.
SF 03 June 1982, Neutron Monitor, Jungfraujach, Switzerland, 3570 m, R=4.5 GV, Chupp
et al. 1983
3.
SF 15 June 1991, COMPTEL aboard GRO, the first Image of SF in Neutrons, En
~20=250 MeV, Moser et al.
4.
SF 31 December 2007, MESSENGER, 0.48 AU, En
=1-8 MeV, Feldman et al. 2010
5.
NEM(Japan)
on ISS since August 2009, En
~40-200 MeV, n-p
scattering process, Koda
et al. 2011
6.
Fermi LAT can measure high energy solar neutrons?...
References samples1.
W.C. Feldman et al., Evidence for extended acceleration of solar
flare ions from 1-8 MeV
solar neutrons detected with the MESSENGER Neutron Spectrometer, JGR, V115, A01102, 2010.
2.
Lev Dorman, Solar Neutrons and Related Phenomena, 2010, Springer, pp 873
Solar Events 2010-2012
Solar Flashes (SF) 2006-2012
13 December 2006 X3.4/4B S06 W24
07 June 2011 M2.5 S22 W53
23 January 2012 M8.7 N18 W21
27 January 2012 X1.7 N27 W71
07 March 2012 X5.4 N17 E27
17 May 2012 M5.1 N11 W76
Selection Criteria: Solar Proton Flux more 100 MeV
> 106 cm-2 day-1 sr-1
Energy, Neutron TOF for Sun-Earth, Arrival Probability of Solar Neutrons (SN) to Earth
1 10 1001000
2000
3000
4000
5000
6000
7000
8000
9000
10000
11000
12000
TOF
for s
olar
neu
trons
, s
Energy of neutrons, MeV
Sun-EarthTime of Flight for Neutrons
TOF for light 499 s
1 10 1001E-6
1E-5
1E-4
1E-3
0,01
0,1
Neutron half-life(878.5 ± 0.8) s
Flux
par
t for
neu
trons
afte
r dec
ay
Energy of neutrons, MeV
Sun-EarthDecay in Flight for Neutrons
Neutron Spectra for Sun-Earth Efficiency of Neutron Registration in ND
100 101 102 10310-9
10-8
10-7
10-6
10-5
10-4
= 6, data x 100
= 4, data x 10
= 2
n = 878.5 s
Neutron production from proton 10-1000 MeV spectrum with = 2, 4, 6 in 1 g/cm2
the Earth orbit
the Sun
Yiel
d / M
eV
Neutron energy, MeV
10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1 100 101 102 103 10410-5
10-4
10-3
10-2
10-1
100
NDalbedo
SNM17
GEANT4
vertical
PAMELA ND
Cal.+ ND
ND
Effi
cien
cy
Neutron energy (MeV)
GOES11-13. Proton Spectra in SF 2006-2012
1 10 100 1000104
105
106
107
108
109
GOES-13, 11
07.06.2011 23.01.2012 27.01.2012 07.03.2012 17.05.2012 06.12.2006 13.12.2006 14.12.2006
Inte
gral
flux
, cm
-2da
y-1s-1
Energy, MeV
Solar protons SF2011-2012 and Dec.2006
Search of Solar Neutrons (SN). Criteria
•
Search of ND counts
increasing after SF near equator on solar side of the Earth during 4-8 min in comparison with counts during 1 circuit before SF (a shift on East ~250)
•
Possible effect of Geomagnetic Cut-off (GM) change by the trajectory shift ~250
needs to be taken into account by analysis
of ND data using the same PAMELA trajectory 1 day before SF•
TOF for solar neutrons on base Sun-Earth can be used for neutron energy measurements. TOF start –
X-ray max in SF.
•
Additional criteria of SN registration waiting –
pre-pulse of p in SCR from n>p++e-+νe
decay during Sun-Earth flight
13 December 2006. SF X3.4/4B 02:40 UT Area 930, S05W23
13.12.2006 and PAMELA. QUICKLOOK Data
n>p+e-+ ?
Pre-pulse
near North
in S1-S3
13.12.2006. QUICKLOOK Data Digitization
563 564 565 566 567 568 569 5700
5000
10000
15000
20000
25000
30000 ND, bottom layer
ND, top layer
ND, bottom layer, shift ~250 E
ND, top layer, shift ~ 250 E
10-3OBT~562-564
N
EquatorEquator
N
S
Num
ber o
f neu
trons
, min
-1
OBTx10-3, s
ND13.12.2006
SF X3.4/4B 02h 40m UTOBT~563850
Shade
Sun~720
SN Effect?
Indian Ocean ~620E ~02h59m
UT 10-3OBT~557-559
12.12.2006. QUICKLOOK Data Digitization
SN 13.12.2006 OBT~564860-565220 ND(b&t): 49073-45873=3200±308
7.0±0.7%
GM 12.12.2006 OBT~463160-463580 ND(b&t): 45210-43048=2162±297
5.0±0.7%
(GM: Cut-off shift ~16.8 -
>17.0 GV)
Total Effect SN-GM: 2.0±1.0% for 25-31 min after SF, En ~32-37 MeV,
Near the Earth In
(32-37 MeV)~960 n/m2s, on the Sun n/p~0.2…
Reasonably
461 462 463 464 465 466 4670
2000
4000
6000
8000
10000
12000
14000
16000
18000
20000
22000
10-3OBT458-460
ND, bottom layer
ND, top layer
ND, bottom layer, shift ~250 E
ND, top layer, shift ~250 E
EquatorEquator
SN
Num
ber o
f neu
trons
, min
-1
OBTx10-3, s
ND12.12.2006
N GM Effect
Indian Ocean ~ 610E
10-3OBT455-457
07 June 2011. SF M2.5 06:41 UT Area 1226, S21W54
07.06.2011 and PAMELA. QUICKLOOK Data
NO
Pre-pulse
Near North
in S1-S3
07.06.2011. QUICKLOOK Data Digitization
2143 2144 2145 2146 2147 2148 2149 2150 21510
5000
10000
15000
20000
25000
30000
35000
S
SN Effect?
Indian Ocean ~850EEquatorEquator
10-3
OBT
2143-2145
SSAA
N
umbe
r of n
eutro
ns, m
in-1
OBTx10-3, s
ND07.06.2011
N
SF 06h 41m
OBT~2143410
10-3
OBT
2140-2142
Shade OBT2143830-2145990
Sun~400
06.06.2011. QUICKLOOK Data Digitization
SN: 07.06.2011 OBT~2147940-2148180 ND: 18852-19150= -
298±195, - 1.6±1.0%
GM: 06.06.2011 OBT~2061510-2061870
ND: 18406-18725= -
319±193, - 1.7±1.0%
(GM: Cut-off shift ~>17.0 –
17.0 GV)
Total Effect SN-GM: 0.1±1.4% for 76-79 min after SF, En ~5.6-5.3 MeV
NO SOLAR NEUTRONS. Only upper limit.
2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 20630
2000
4000
6000
8000
10000
12000
14000
16000
18000
20000
Eq.
SN
Num
ber o
f Neu
trons
, min
-1
OBTx10-3, s
ND06.06.2011
SAA
N
S
Eq.
GM Effect
Indian Ocean ~850E
10-3OBT2053-2056
23 January 2012. SF M8.7 03:59 UT Area 1402, N33W21
23.01.2012 and PAMELA. QUICKLOOK Data
n>p+e+…?
Pre-pulse
near North
in S1-S3
23.01.2012. QUICKLOOK Data Digitization
196 197 198 199 200 201 2020
5000
10000
15000
20000
25000
EquatorEquator
SN Effect?
Background before SF 23.01.2012
10-3OBT192-194
S
N
umbe
r of n
eutro
ns, m
in-1
OBTx10-3, s
ND23.01.2012
SF M8.7 03h 59m
OBT~197800
N
S
Shade OBT197680-199600
Sun~700
E Africa~ 400E
10-3OBT195-197
Shade
22.01.2012. QUICKLOOK Data Digitization
112 113 114 115 116 1170
5000
10000
15000
EquatorEquator
E Shiftof Orbit~250
GM Effect ?
E Africa ~ 400E
10-3OBT~108-111
N
Num
ber o
f neu
trons
, min
-1
ND22.01.2012
OBTx10-3, s
S
Background before SF 23.01.2012
10-3OBT~106-108
SN: 23.01.2012 OBT~200360-200600 ND:14801-13767=1034±169,
7.5±1.2%
GM: 22.01.2012 OBT~113670-114030 ND: 22151-20645=1506±207,
7.3±1.6%
(GM: Cut-off shift ~ 16.0-16.6GV)
Total effect SN-GM: 0.2 ± 1.6 % for ~52-56 min after SF, En ~ 9-12 MeV
NO SOLAR NEUTRONS. Only upper limit.
27 January 2012. SF X1.7 18:36 UT Area 1402, N27W71
27.01.2012. QUICKLOOK Data
NO
Pre-pulse
near North
in S1-S3
27.01.2012. QUICKLOOK Data Digitization
594 595 596 597 598 5990
5000
10000
15000
20000
25000
30000
EquatorEquator
SN Effect?
Pacific Ocean ~1700E
N
umbe
r of n
eutro
ns, m
in-1
OBTx10-3, s
ND27.01.2012
SF X1.7 18h 36m
OBT ~595760
Shade OBT 595640-597380
Shade
Sun~660
N
SS
10-3
OBT
590-592
26.01.2012. QUICKLOOK Data Digitization
506 507 508 509 510 511 512 513 5140
2000
4000
6000
8000
10000
12000
14000
16000
18000
Equator
GM Effect?
Pacific Ocean ~1700E
SN
Num
ber o
f Neu
trons
, min
-1
OBTx10-3, s
ND26.01.2012
S
Equator
SN: 27.01.2012 OBT~598040-598280 ND: 13507-13955= -
448±166, - 3.2±1.2%
GM: 26.01.2012 OBT~511410-511890 ND: 27209-28040= -
831±235, -3.0±0.8%
(GM Cut-off shift ~15.5-15.0 GV)
Total Effect SN-GM: - 0.2±1.5% for 37-41 min after SF, En ~20 MeV
NO SOLAR NEUTRONS. Only upper limit
07 March 2012. SF X5.4 00:24 UT Area 1430, N14E27
07.03.2012. QUICKLOOK Data
n>p+e+…?
Pre-pulse
near South
in S1-S3
07.03.2012. QUICKLOOK Data Digitization
1324 1326 1328 1330 1332 1334 1336 1338 1340 1342 1344 13460
2000
4000
6000
8000
10000
12000
14000
16000
18000
20000
22000
~1160E Sun
~410E Sun~660E
Sun
SS N
N
bottom layer top layer - 1 circuit
SAA
Eq.
Eq. Eq.
10-3
OBT
~1329-1331
S SN
SF X5.4 00h 24m
OBT~1323840
N
umbe
r of n
eutro
ns, m
in-1
OBTx10-3, s
ND07.03.2012
N
Nodata 10
-3OBT
~1335-1339
Eq.SAA
~910E Sun
06.03.2012. QUICKLOOK Data Digitization
SF 07.03.2012 X5.4 00:24 UT, Common Data: Fermi LAT found Eγ
=0.1-4.0GeV(!), the first SCR went in ~03:40!!!
NB. No ND data near 00:57 UT (En
~20 MeV) through SAA and no QuickLook
data near 01:47 UT (En
~4 MeV)…
SN: 07.03.2012 OBT~1340410-1340650 ND: 11871-11515=356±234 3.1±2.0%
GM: 06.03.2012 OBT~1253910-1254150 ND: 11797-11512=276±153 2.4±1.3%
Total Effect SN-GM: 0.7± 2.4% for ~279 min after SF. En = ? NO SOLAR NEUTRONS. Only upper limit.
SN: 07.03.2012 OBT~1346110-1346710 ND: 16080-15226=854±177 5.6±1.2%
GM: 06.03.2012
OBT~1259660-1259900 ND: 12346-11797=549±155 4.7±1.3%
Total Effect SN-GM: 0.9±1.7% for ~371 min after SF. En = ? NO SOLAR NEUTRONS. Only upper limit.
1240 1242 1244 1246 1248 1250 1252 1254 1256 1258 12600
2000
4000
6000
8000
10000
12000
14000
16000
18000
20000 bottom layer
top layer
- 1 circle
S S SN N N
~1160E Eq.
~910E Eq.
~660E Eq.
SAA SAA
Num
ber o
f neu
trons
, min
-1
OBTx10-3, s
ND06.03.2012
SAA~410E Eq.
N S
17 May 2012. SF M5.1 01:47 UT Area 1476, N11W76
17.05.2012. QUICKLOOK Data
n>p+e+…?
Pre-pulse
Near North
in S1-S3
17.05.2012. QUICKLOOK Data Digitization
30 31 32 33 34 350
5000
10000
15000
20000
25000
Background before SF 17.05.2012
S
SN Effect?
E Africa ~ 400E
Sun~830
Sun~860
SunN
N
umbe
r of n
eutro
ns, m
in-1
OBTx10-3, s
ND17.05.2012
S
SF M5.1 01h 47m OBT~31880
10-3OBT 26-28
16.05.2012. QUICKLOOK Data Digitization
SN: 17.05.2012 OBT~33770-35010 ND(b&t):
31983-31289=694±252, 2.2±0.8%
GM: 16.05.2012 OBM~454800-454980 ND(b&t): 23194-22981= 213±215, 0.9±0.9%
(GM: Cut-off shift ~ 15.9-16.8GV). NB. Quality of QL data for 16.05.2012 is so so…
Total Effect SN-GM: 1.3±1.2% for 32-36 min after SF, En ~20-18 MeV
PROBABLY SOLAR NEUTRONS…
452 453 454 455 456 457 4580
5000
10000
15000
E Shiftof Orbit~250N
umbe
r of n
eutro
ns, m
in-1
E Shiftof Orbit~250
N
ND16.05.2012
Background before SF 17.05.2012
SGM Effect ?
E.Africa ~ 400E
OBTx10-3, s
Summary
•
13 December 2006 X3.4/4B S06 W24 En ~35 MeV 2.9±1.4% Yes?•
07 June 2011 M2.5 S22 W53 En ~5 MeV 0.1±1.4% No
•
23 January 2012 M8.7 N18 W21 En ~10 MeV 0.2±1.6% No•
27 January 2012 X1.7 N27 W71 En ~20 MeV 0.2±1.5% No
•
07 March 2012 X5.4 N17 E27 En ~ ? MeV 0.9±2.4% No?•
17 May 2012 M5.1 N11 W76 En ~35 MeV 1.3±1.2% Yes?
Solar Flare Class Area Energy Effect SN(GM)
CONCLUSION
•
Probably solar neutrons shouid be generated more or less in each Solar Flash (SF)
•
Analysis of the PAMELA QL Data for SF 2006-2012 show that solar neutrons probably were found recently in Solar Flare 13 December 2006…The same was probably also during SF 17 May 2012...
•
This work can be extended on more precise level using Level 2 data. For PAMELA people who study solar flares…
•
P.S. During the nearest Solar Max PAMELA can have data complex for SCR spectra in time, 1H, 2H, 3H, 3He,
4He isotopes and Solar Neutrons…
Best wishes from St. Petersburg :~)
Thanks