Solar Neutrons in the PAMELA Experiment 2006-2012€¦ · SF2011-2012 and Dec.2006. Search of Solar Neutrons (SN). Criteria

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


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


NO

Pre-pulse

Near North

in S1-S3


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


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


n>p+e+…?

Pre-pulse

near North

in S1-S3


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


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


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


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


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


n>p+e+…?

Pre-pulse

near South

in S1-S3


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


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


n>p+e+…?

Pre-pulse

Near North

in S1-S3


30 31 32 33 34 350

5000

10000

15000

20000

25000


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


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


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

Documents

Solar Neutrons in the PAMELA Experiment 2006-2012€¦ · SF2011-2012 and Dec.2006. Search of Solar Neutrons (SN). Criteria