Pre-Supernova (Anti)Neutrino Emission Due to Weak-Interaction Reactions with Hot Nuclei

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

In this study, the authors studied the influence of temperature on pre-supernova (anti)neutrino emission. For the stellar structure and evolution, they use the widely used MESA code. They introduce a new method, which is an extension of standard QRPA to finite temperatures.  They show that the TQRPA method has the key advantage of being thermodynamically consistent. It leads to a stronger nuclear contribution to neutrino emission than what is predicted by the Q_eff (hereafter effective) approach.

The authors find that for electron neutrinos, the inclusion of Gamow-Teller transitions from thermally excited nuclear states increases the luminosity at higher energies and produces a harder spectrum relative to the effective method. While flavor oscillations reduce the overall e-neutrino luminosity in both approaches, they do not alter the spectral shape.

In the case of electron antineutrinos, TQRPA calculations reveal that at high nuclear temperatures the neutral-current de-excitation channel becomes especially important. When oscillations are included, this mechanism significantly enhances the fraction of high-energy electron anti-neutrino in the spectrum—a feature absent in the effective method.

Overall, the results found by the authors highlight the importance of employing a microscopic and thermodynamically consistent framework as exemplified by TQRPA. Its predictions differ qualitatively from those of the effective method and carry direct implications for the detectability of pre-supernova neutrinos in terrestrial experiments, with potential impact on early-warning systems for core-collapse supernovae.

I warmly recommend the publication of this article in "Particles".

Author Response

We deeply appreciate the reviewer’s recognition of the scientific value of our work and the warm recommendation to publish the manuscript in "Particles".

Reviewer 2 Report

Comments and Suggestions for Authors

This paper is easy to review, it discusses a very interesting and topical problem: emission of neutrinos from large stars close to the final stage, supernova explosion and collapse to a neutron star. Supernovas close by a very rare and very brief,  but this pre-explosion stage lasts much longer and there is a definite chance that neutrino observatories will soon be able to observe neutrinos from it and thus its properties. The stellar structure of the pre-equilibrium stage is also an interesting astrophysical problem as such and in this way one could have a direct observation thereof.  For this one needs computations of neutrino emission from pre-equilibrium stages and this article provides them.

I have no special advice to the authors, just continue along the same line.

I recommend publication.

 

Author Response

We gratefully acknowledge the referee’s positive assessment and recommendation for publication.

Reviewer 3 Report

Comments and Suggestions for Authors

The article is complete and presents how TQRPA calculations neutrino oscillations predict temporal evolution of luminosities and spectra for a specific pre-supernova model.

The only minor comment would be to discuss how neutrino flux which is orders of magnitude greater than for antineutrinos may be detected. IBD is the only one discussed and employed method for pre/supernova detection e.g. Gd-SK. The article sates that TQRPA + ND result in high flux and energy for neutrinos .. so maybe coherent scattering would be more sensitive for presupernova detection ?

Author Response

We sincerely thank the referee for  careful reading of the manuscript and for the insightful suggestion. We fully agree that, given the significantly enhanced high-energy electron neutrino flux predicted by our TQRPA calculations, alternative detection channels beyond inverse beta decay (IBD) deserve attention. 

Comments 1: The only minor comment would be to discuss how neutrino flux which is orders of magnitude greater than for antineutrinos may be detected. IBD is the only one discussed and employed method for pre/supernova detection e.g. Gd-SK. The article sates that TQRPA + ND result in high flux and energy for neutrinos .. so maybe coherent scattering would be more sensitive for presupernova detection ?

 

Response 1: In response to this comment, we have added  the following discussion at the end of the Conclusion section

In~\cite{Dzhioev_MNRAS527} we demonstrated that the ND process can significantly enhance the detection rate of pre-supernova $\bar{\nu}_e$ via inverse beta-decay. However, as illustrated in Fig.~\ref{spectra_oscill}, during the pre-supernova phase the $\nu_e$ flux exceeds the $\bar{\nu}_e$ flux by orders of magnitude. This suggests that detection channels sensitive to electron neutrinos may play a crucial role in observing the final hours of stellar evolution. In future work, we plan to investigate how thermal effects  -- particularly the hardening of the $\nu_e$ spectrum predicted by the TQRPA framework -- influence the detectability of pre-supernova $\nu_e$ through alternative interaction channels, including elastic scattering on electrons, charged- and neutral-current interactions with nuclei, and coherent elastic neutrino–nucleus scattering.