Time profile of the neutrino burst from the supernova 1987A

Author(s):  
Hideyuki Suzuki ◽  
Katsuhiko Sato
Keyword(s):  
1988 ◽  
Vol 108 ◽  
pp. 426-427
Author(s):  
Hideyuki Suzuki ◽  
Katsuhiko Sato

SN1987A gave us the first opportunity to study the supernova core directly by providing us the neutrino signal from the core. The observational data of the neutrino flux detected by Kamiokande[1] and IMB[2] show surprisingly good agreements with the theoretical predictions as a whole[3,4]. The fundamental concept of the collapse driven supernova explosion is confirmed for the first time. On the other hand, there are some puzzles. The most peculiar feature of the data is the 7 seconds gap of the Kamiokande data. The first 8 events of Kamiokande were detected in 2 seconds, following the 7 seconds gap and the last 3 events in 4 seconds. Of course just only 7 seconds gap is not unnatural if small neutrino flux come. But there were detected 3 events after the gap. These 3 events may not be produced by the weak flux. We can estimate the time integrated luminosity of corresponding to the last 3 events and get the large value such as 7 · 1052erg [5]. Can we get out of this inconsistency, 3 events after the 7 seconds gap? If not, we may need to consider some nonstandard mechanism of the neutrino emission at the late time. In order to investigate the probability of the case in which there is a 7 seconds gap before 3 events, we have performed Monte Carlo simulations for the simple model of neutrino flux.


1989 ◽  
Vol 8 ◽  
pp. 229-237
Author(s):  
L.N. Alexeyeva

AbstractObservations of the neutrino burst from Supernova 1987A by water Cherenkov detectors (KAMIOKANDE II, IMB) and liquid scintillator detectors (Baksan, Mont Blanc) are reviewed. It is shown that neutrino signal from SN 1987A was observed. There are 24 events in three detectors (KAMIOKANDE II, IMB, Baksan) recorded at 7:35 UT. The average properties of the signal (effective neutrino temperature, total energy of neutrino emission, burst duration) are consistent with the general theoretical description of supernova explosions. Special attention is concentrated on individual characteristics of the signals detected and the available discrepancies of the model estimates. Time profile of the neutrino burst, estimates of effective neutrino temperatures and total neutrino energies, angular distributions of the events are discussed. These properties point out, probably, a more compound picture of the phenomenon. The more detail analysis of the experimental data is needed and all possibilities must be at least considered. Based upon the Baksan observations, an upper limit of 0.35 core collapse in the Galaxy per year (90% C.L.) is shown.


1986 ◽  
Vol 51 (8) ◽  
pp. 1795-1801
Author(s):  
Hana Hájková ◽  
Zdeněk Pavlíček ◽  
Vítěz Kalous

The time profile of changes in the oxygen saturation curves of human hemoglobin in the presence of benzene was investigated. The partial oxygen pressure p50, necessary for a half saturation, decreases during the first 3.5 h of interaction of hemoglobin with benzene and did not change afterwards. The character of changes in Hill's coefficient was similar. The oxygen saturation was modeled both for hemoglobin alone and, using MWC as a model of allosteric interaction, also for hemoglobin and benzene in a computer.


2021 ◽  
Vol 10 (4) ◽  
pp. 589
Author(s):  
Mariusz G. Fleszar ◽  
Paulina Fortuna ◽  
Marek Zawadzki ◽  
Paweł Hodurek ◽  
Iwona Bednarz-Misa ◽  
...  

Excessive endocrine response to trauma negatively affects patients’ well-being. Cortisol dynamics following robot-assisted colorectal surgery are unknown. We aimed at determining the impact of cancer pathology and surgery-related factors on baseline cortisol levels and analyzed its time-profile in colorectal cancer patients undergoing open or robot-assisted surgery. Cortisol levels were measured using liquid chromatography quadrupole time-of-flight mass spectrometry. Baseline cortisol was not associated with any patient- or disease-related factors. Post-surgery cortisol increased by 36% at 8 h and returned to baseline on postoperative day three. The cortisol time profile was significantly affected by surgery type, estimated blood loss, and length of surgery. Baseline-adjusted cortisol increase was greater in females at hour 8 and in both females and patients from open surgery group at hour 24. Solely in the open surgery group, cortisol dynamics paralleled changes in interleukin (IL)-1β, IL-10, IL-1ra, IL-7, IL-8 and tumor necrosis factor (TNF)-α but did not correlate with changes in IL-6 or interferon (IFN)-γ at any time-point. Cortisol co-examined with C-reactive protein was predictive of surgical site infections (SSI) with high accuracy. In conclusion, patient’s sex and surgery invasiveness affect cortisol dynamics. Surgery-induced elevation can be reduced by minimally invasive robot-assisted procedures. Cortisol and C-reactive protein as SSI biomarkers might be of value in the evaluation of safety of early discharge of patients.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Blai Casals ◽  
Karin A. Dahmen ◽  
Boyuan Gou ◽  
Spencer Rooke ◽  
Ekhard K. H. Salje

AbstractAcoustic emission (AE) measurements of avalanches in different systems, such as domain movements in ferroics or the collapse of voids in porous materials, cannot be compared with model predictions without a detailed analysis of the AE process. In particular, most AE experiments scale the avalanche energy E, maximum amplitude Amax and duration D as E ~ Amaxx and Amax ~ Dχ with x = 2 and a poorly defined power law distribution for the duration. In contrast, simple mean field theory (MFT) predicts that x = 3 and χ = 2. The disagreement is due to details of the AE measurements: the initial acoustic strain signal of an avalanche is modified by the propagation of the acoustic wave, which is then measured by the detector. We demonstrate, by simple model simulations, that typical avalanches follow the observed AE results with x = 2 and ‘half-moon’ shapes for the cross-correlation. Furthermore, the size S of an avalanche does not always scale as the square of the maximum AE avalanche amplitude Amax as predicted by MFT but scales linearly S ~ Amax. We propose that the AE rise time reflects the atomistic avalanche time profile better than the duration of the AE signal.


1991 ◽  
Vol 52 (2) ◽  
pp. 132-137 ◽  
Author(s):  
R. Torre ◽  
R. Righini ◽  
P. Foggi ◽  
L. Angeloni
Keyword(s):  

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