Download presentation
Presentation is loading. Please wait.
Published byAriana Sandoval Modified over 10 years ago
1
Piero Galeotti Università di Torino and INFN GianVittorio Pallottino Università di Roma and INFN Guido Pizzella Università di Roma Tor Vergata INFN- Frascati SN1987A revisited
2
Results from LSD and KAMIOKANDE
3
Hours of 23 February 1987 Mont Blanc ~ 45 pulses/hour > 5 MeV Kamiokande ~ 85 pulses/hour > 7.5 MeV (7.5 MeV corresponds to Nhit=20) 0 8 LSD Kamioka 2 h 56 m 7 h 35 m
4
Mont Blanc neutrino telescope 1987
6
Kamiokande neutrino telescope 1987
8
Hirata et al. PR D 448 (1988)
9
May the Supernova Bang more than once ?
10
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
11
relative Kamiokande time IMB no IMB
12
11 in 12 s Nh>20 11 in 12 s Nh>20 7 in 6 s Nh > 21 7 in 6 s Nh > 21
13
relative Kamiokande time IMB E>15 MeV no IMB E <15 MeV
14
Correlation of the Kamiokande and LSD neutrino detectors with the Rome and Maryland gravitational wave detectors
16
We have searched for possible correlations between the signals of the neutrino detectors and those of the g.w. detectors
17
C ( ) = 1/N i { E R (t i + ) + E M (t i + )} N number of pulses (in the neutrino detector) in a given period (say, one hour) t i time of a pulse common time shift for a possible delay The algorithm
18
C b ( 1, 2 ) = 1/N { E R ( 1 ) + E M ( 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
19
We perform N random extractions of 1, 2 for the background and count the number n of times when C b ( 1, 2 ) > C( )
20
C b ( 1, 2 ) with random 1, 2 C( )=72.6 K N= one million random data for the background
21
Mont Blanc 1:45 - 3:45 ( 5-neutrinos at 2:56 U.T.) +1.2 (second) n C(-1.1)
22
What about Kamiokande ? (absolute time uncertainty ±1 min)
23
best c =7.8 s c is the time correction in s
24
IMB K Kamiokande has a time error ± 1 minute Kamiokande time correction + 7.8 s Schramm and Truran (1990)
26
New analysis of the original data
27
hours of 23 February with time correction of 7.8 s Periods of one hour moved in steps of 6 min n (N=10 5 ) n (N=10 4 )
28
CONCLUSIONS This new analysis reinforces the idea of a long duration activity of SN1987A in the neutrino emission.
29
…noi non doviamo desiderare che la natura si accomodi a quello che parrebbe meglio disposto et ordinato a noi, ma conviene che noi accomodiamo lintelleto nostro a quello che ella ha fatto, sicuri tale essere lottimo et non altro. Galileo in 1612 to Federico Cesi. THE END
Similar presentations
© 2024 SlidePlayer.com Inc.
All rights reserved.