Combining neutrino experimental light-curves for pointing to the next galactic core-collapse supernova

AbstractThe multi-messenger observation of the next galactic core-collapse supernova will shed light on the different physical processes involved in these energetic explosions. Good timing and pointing capabilities of neutrino detectors would help in the search for an electromagnetic or gravitational-wave counterparts. An approach for the determination of the arrival time delay of the neutrino signal at different experiments using a direct detected neutrino light-curve matching is discussed. A simplified supernova model and detector simulation are used for its application. The arrival time delay and its uncertainty between two neutrino detectors are estimated with chi-square and cross-correlation methods. The direct comparison of the detected light-curves offers the advantage to be model-independent. Millisecond time resolution on the arrival time delay at two different detectors is needed. Using the computed time delay between different combinations of currently operational and future detectors, a triangulation method is used to infer the supernova localisation in the sky. The combination of IceCube, Hyper-Kamiokande, JUNO and KM3NeT/ARCA provides a 90% confidence area of $$140\pm 20\,\hbox {deg}^2$$ 140 ± 20 deg 2 . These low-latency analysis methods can be implemented in the SNEWS alert system.

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The study of short orbital period of delta scuti pulsating variable stars

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320003610 ◽

2019 ◽

Vol 15 (S356) ◽

pp. 407-407

Author(s):

Abduselam Mohammed

Keyword(s):

Time Delay ◽

Orbital Period ◽

Binary Stars ◽

Arrival Time ◽

Periodic Variation ◽

Variable Stars ◽

Orbital Elements ◽

Pulsating Stars ◽

Delta Scuti ◽

Arrival Time Delay

AbstractAs a pulsating star moves in its binary orbit, the path length of the light between us and the star varies, leading to the periodic variation in the arrival time of the signal from the star to us (earth). With the consideration of pulsators light arrival time delay effects several new methods which allows using Kepler photometric data (light curves) alone to find binary stars have been recently developed. Among these modern techniques we used binarogram method and we identified that several δSct pulsating stars have companions. The application of these method on detecting long periods(i.e. longer than about 50 d) δSct pulsating stars is not new, but the uniqueness of this study is we verified that it is also applicable to detect and determine the orbital elements of short periods (i.e short orbital period) δSct pulsating stars. With this investigation, we identified the possible way to overcome effects of fictious peaks, even, on the maximum peaks helpful to verify weather the star has companion or not depend up on the existence of the time-delay. Then, we applied the technique on known binary stars and their orbital elements are previously published. Finally, we identified some new short orbital period δSct pulsating stars and obtained their orbital frequency and period with the same procedures. Because of with our attempts we succeeded and verified the applicability of the method (the Binarogram method) on these stars (i.e short orbital period) for the first time, we expect that our present study will play a great role for similar study and to improve our binary statistics.

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TOWARD THREE-DIMENSIONAL MODELS OF CORE-COLLAPSE SUPERNOVA SPECTRA AND LIGHT CURVES: MOTIVATIONS AND CHALLENGES

Open Issues in Core Collapse Supernova Theory ◽

10.1142/9789812703446_0022 ◽

2005 ◽

Author(s):

R. C. THOMAS

Keyword(s):

Three Dimensional ◽

Light Curves ◽

Core Collapse ◽

Core Collapse Supernova ◽

Dimensional Models ◽

Three Dimensional Models

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A low-luminosity core-collapse supernova very similar to SN 2005cs

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1743 ◽

2020 ◽

Vol 496 (3) ◽

pp. 3725-3740

Author(s):

Zoltán Jäger ◽

József Vinkó ◽

Barna I Bíró ◽

Tibor Hegedüs ◽

Tamás Borkovits ◽

...

Keyword(s):

Monte Carlo ◽

Small Population ◽

Light Curves ◽

Physical Parameters ◽

Expansion Velocity ◽

Core Collapse ◽

Monte Carlo Code ◽

Type Ii ◽

Core Collapse Supernova ◽

Analytic Models

ABSTRACT We present observations and analysis of PSN J17292918+7542390, a low-luminosity Type II-P supernova (LL SN IIP). The observed sample of such events is still low, and their nature is still under debate. Such SNe are similar to SN 2005cs, a well-observed LL Type II-P event, having low expansion velocities, and small ejected 56Ni mass. We have developed a robust and relatively fast Monte Carlo code that fits semi-analytic models to light curves of core-collapse SNe. This allows the estimation of the most important physical parameters, like the radius of the progenitor star, the mass of the ejected envelope, the mass of the radioactive nickel synthesized during the explosion, among others. PSN J17292918+7542390 has $R_0 = 91_{-70}^{+119} \times 10^{11} \, \text{cm}$, $M_\text{ej} = 9.89_{-1.00}^{+2.10} \, \mathrm{ M}_{\odot }$, $E_{\mbox{kin}} = 0.65_{-0.18}^{+0.19} \, \text{foe}$, and $v_{\mbox{exp}} = 3332_{-347}^{+216}$ km s−1, for its progenitor radius, ejecta mass, kinetic energy, and expansion velocity, respectively. The initial nickel mass of the PSN J17292918+7542390 turned out to be $1.55_{-0.70}^{+0.75} \times 10^{-3} \, \mathrm{M}_{\odot }$. The measured photospheric velocity at the earliest observed phase is 7000 km s−1. As far as we can tell based on the small population of observed LL SNe IIP, the determined values are typical for these events.

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Probing neutrino decay scenarios by using the Earth matter effects on supernova neutrinos

Journal of Cosmology and Astroparticle Physics ◽

10.1088/1475-7516/2022/01/003 ◽

2022 ◽

Vol 2022 (01) ◽

pp. 003

Author(s):

Edwin A. Delgado ◽

Hiroshi Nunokawa ◽

Alexander A. Quiroga

Keyword(s):

Core Collapse ◽

Neutrino Detectors ◽

Core Collapse Supernova ◽

Matter Effects ◽

The Earth ◽

Two Factors ◽

Matter Effect ◽

The Difference ◽

Neutrino Fluxes ◽

Neutrino Decay

Abstract The observation of Earth matter effects in the spectrum of neutrinos coming from a next galactic core-collapse supernova (CCSN) could, in principle, reveal if neutrino mass ordering is normal or inverted. One of the possible ways to identify the mass ordering is through the observation of the modulations that appear in the spectrum when neutrinos travel through the Earth before they arrive at the detector. These features in the neutrino spectrum depend on two factors, the average neutrino energies, and the difference between the primary neutrino fluxes of electron and other flavors produced inside the supernova. However, recent studies indicate that the Earth matter effect for CCSN neutrinos is expected to be rather small and difficult to be observed by currently operating or planned neutrino detectors mainly because of the similarity of average energies and fluxes between electron and other flavors of neutrinos, unless the distance to CCSN is significantly smaller than the typically expected one, ∼ 10 kpc. Here, we are looking towards the possibility if the non-standard neutrino properties such as decay of neutrinos can enhance the Earth matter effect. In this work we show that invisible neutrino decay can potentially enhance significantly the Earth matter effect for both νe and ν̅e channels at the same time for both mass orderings, even if the neutrino spectra between electron and other flavors of neutrinos are very similar, which is a different feature not expected for CCSN neutrinos with standard oscillation without the decay effect.

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