Piero GaleottiUniversità di Torino and INFN

GianVittorio PallottinoUniversità di Roma and INFN

Guido PizzellaUniversità di Roma Tor VergataINFN- Frascati

SN1987A revisited

Results from LSD and KAMIOKANDE

Hours of 23 February 1987

Mont Blanc ~ 45 pulses/hour > 5 MeVKamiokande ~ 85 pulses/hour > 7.5 MeV (7.5 MeV corresponds to Nhit=20)

0 8

LSD

Kamioka

2h56m

7h35m

Mont Blanc neutrino telescope 1987

Kamiokande neutrino telescope 1987

Hirata et al.PR D 448 (1988)

May the Supernova Bang more than once ?

A.DeRujula Phys.Lett. B193:514 (1987) V.S. Berezinsky, C. Castagnoli, V.I .Dokuchaev, P.Galeotti On the possibility of a two-bang supernova collapse N. Cimento 11, 3, 287 (1988) V.S.Imshennik Space Science Rev., 74, 325 (1995) V.S.Imshennik and O.G.Ryashskaya Astronomy Letters, 30,14-31 (2004)

Kamiokande neutrino telescope 1987

The data have been supplied to us by the Kamiokande collaboration in 1987. We have acknowledged the

collaboration in several papers

New analysis

relative Kamiokande time

IMB

noIMB

11 in 12 sNh>20

11 in 12 sNh>20

7 in 6 sNh > 217 in 6 sNh > 21

relative Kamiokande time

IMBE>15 MeV

noIMB

E<15 MeV

Correlation of the Kamiokande and LSD neutrino detectors with

the Rome and Maryland gravitational wave detectors

We have searched for possible correlations between the signals

of the neutrino detectors and those of the g.w. detectors

C() =

1/Ni{ER(ti+ ) + EM(ti+ )}

N number of pulses (in the neutrino detector)

in a given period (say, one hour)

ti time of a pulse

common time shift for a possible delay

The algorithm The algorithm

Cb(1, 2) =

1/N{ER(1) + EM(2)}

N number of pulses (in the neutrino detector)

in a given period (say, one hour)

1, 2 random time shifts for the background

The background

We perform N random extractions of 1, 2 for the background and count the number n of times when

Cb(1, 2) > C()

Cb(1, 2) with random 1, 2

C()=72.6 K

N= one million random data for the background

Mont Blanc 1:45 - 3:45 ( 5-neutrinos at 2:56 U.T.)

+1.2 (second)

n

C(-1.1)

What about Kamiokande ?

(absolute time uncertainty ±1 min)

best c=7.8 s

c is the time correction in s

IMB

K

Kamiokande has a time error ± 1 minute

Kamiokande time correction + 7.8 s

Schramm and Truran (1990)

New analysis of the original data

hours of 23 February

with time correction of 7.8 s

Periods of one hour moved in steps of 6 min

n (N=105)

n(N=104)

CONCLUSIONS

This new analysis reinforces the idea of a long duration activity of

SN1987A in the neutrino emission.

…noi non doviamo desiderare che la natura si accomodi a quello che parrebbe meglio disposto et ordinato a noi, ma conviene che noiaccomodiamo l’intelleto nostro a quello che ella ha fatto, sicuri tale essere l’ottimo et non altro.

Galileo in 1612 to Federico Cesi.

THE ENDTHE END