123 research outputs found
Terrestrial detection of hidden vectors produced by solar nuclear reactions
Solar nuclear reactions can occasionally produce sub-MeV elusive beyond the
Standard Model particles that escape the solar interior without further
interactions. This study focuses on massive spin-one particles. We construct
the general theoretical framework and identify two crucial mixing sources
involving the photon, which facilitate communication between the hidden and
visible sectors: kinetic mixing with the photon, and plasma-induced mixing due
to thermal electron loops. For both cases, we focus on the second stage of the
solar proton-proton chain and evaluate the fluxes of monochromatic 5.49~MeV
hidden vectors produced by the nuclear
reaction. We then investigate their terrestrial detection via Compton-like
scatterings. The incoming fluxes are polarized, and we evaluate the cross
sections for Compton-like scatterings for transverse and longitudinal vectors.
Finally, we apply this framework to a concrete case by investigating the
sensitivity of the forthcoming Jiangmen Underground Neutrino Observatory (JUNO)
experiment and identifying parameter space where current terrestrial bounds
will be improved.Comment: 40 pages, 9 figures; v2: numerical mistake in the analysis corrected,
updated results and discussio
Probing high-energy solar axion flux with a large scintillation neutrino detector
We investigate the 5.49 MeV solar axions flux produced in the p(d,\,
^{3}{\rm He})a reaction and analyze the potential to detect it with the
forthcoming large underground neutrino oscillation experiment Jiangmen
Underground Neutrino Observatory (JUNO). The JUNO detector could reveal axions
through various processes such as Compton and inverse Primakoff conversion, as
well as through their decay into two photons or electron-positron pairs inside
the detector. We perform a detailed numerical analysis in order to forecast the
sensitivity on different combinations of the axion-electron (),
axion-photon (), and isovector axion-nucleon ()
couplings, using the expected JUNO data for different benchmark values of axion
mass in a model-independent way. We find that JUNO would improve by
approximately one order of magnitude current bounds by Borexino and it has the
best sensitivity among neutrino experiments.Comment: 21 pages, 7 figure
Heavy axion-like particles and core-collapse supernovae: constraints and impact on the explosion mechanism
Heavy axion-like particles (ALPs), with masses keV, coupled
with photons, would be copiously produced in a supernova (SN) core via
Primakoff process and photon coalescence. Using a state-of-the-art SN model, we
revisit the energy-loss SN 1987A bounds on axion-photon coupling. Moreover, we
point out that heavy ALPs with masses MeV and axion-photon
coupling GeV would decay into
photons behind the shock-wave producing a possible enhancement in the energy
deposition that would boost the SN shock revival.Comment: v2 (32 pages, 21 figure): revised version. Matches the published
version on JCAP. Major changes to improve the robustness of the bound. Added
two Appendices on the possible constraining criteria and on the effect of the
SN progenitor mass on the boun
Proto-neutron stars as cosmic factories for massive axion-like-particles
The parameter space of massive axion-like-particles (ALPs) with MeV and coupled with nucleons is largely unexplored. Here,
we present new constraints in this parameter region. In doing so, we
characterize the supernova emissivity of heavy ALPs from a proto-neutron star,
including for the first time mass effects in both nucleon-nucleon
Bremsstrahlung and pionic Compton processes. In addition, we highlight novel
possibilities to probe the couplings with photons and leptons from supernova
ALP decays.Comment: 13 pages, 8 figure
Constraints on the coupling with photons of heavy axion-like-particles from Globular Clusters
We update the globular cluster bound on massive ( up to a few 100 keV)
axion-like particles (ALP) interacting with photons. The production of such
particles in the stellar core is dominated by the Primakoff and by the photon coalescence process . The latter,
which is predominant at high masses, was not included in previous estimations.
Furthermore, we account for the possibility that axions decay inside the
stellar core, a non-negligible effect at the masses and couplings we are
considering here. Consequently, our result modifies considerably the previous
constraint, especially for keV. The combined constraints from
Globular Cluster stars, SN 1987A, and beam-dump experiments leave a small
triangularly shaped region open in the parameter space around MeV and GeV. This is informally
known as the ALP "cosmological triangle" since it can be excluded only using
standard cosmological arguments. As we shall mention, however, there are viable
cosmological models that are compatible with axion-like particles with
parameters in such region. We also discuss possibilities to explore the
cosmological triangle experimentally in upcoming accelerator experiments.Comment: 10 pages, 5 figures. v2: Revised version. Matches the version
published on PLB. Improved the discussion on axion energy transfer in HB
stars. Added two Appendices on photon-axion transition rate from Primakoff
conversion and on photon coalescenc
Getting the most on supernova axions
Axion-like particles (ALPs) coupled to nucleons might be copiously emitted
from a supernova (SN) core. We extend existing bounds on free-streaming ALPs to
the case in which these are so strongly-interacting with the nuclear matter to
be trapped in the SN core. For strongly-interacting ALPs, we also extend the
bound from the absence of an ALP-induced signal in Kamiokande-II neutrino
detector at the time of SN 1987A. We find that combining the different
arguments, SNe exclude values of axion-nucleon coupling
for ALP masses MeV. Remarkably, in the case of canonical QCD
axion models, the SN bounds exclude all values of eV.
This result prevents the possibility for current and future cosmological
surveys to detect any axion signal.Comment: 12 pages, 6 figure
Getting the most on supernova axions
© 2024 The Author(s). Published by the American Physical Society. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Axionlike particles (ALPs) coupled to nucleons might be copiously emitted from a supernova (SN) core. We extend existing bounds on free-streaming ALPs to the case in which these are so strongly interacting with the nuclear matter to be trapped in the SN core. For strongly interacting ALPs, we also extend the bound from the absence of an ALP-induced signal in Kamiokande-II neutrino detector at the time of SN 1987A. We find that combining the different arguments, SNe exclude values of ALP-nucleon coupling gaN 10-9 for ALP masses ma 1 MeV. Remarkably, in the case of canonical QCD axion models, the SN bounds exclude all values of ma 10-2 eV. This result prevents the possibility for current and future cosmological surveys to detect any signatures due to hot dark matter QCD axion mass.Peer reviewe
Cross section for supernova axion observation in neutrino water ÄŒherenkov detectors
©2024 American Physical Society. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1103/PhysRevC.109.015501Axions coupled to nucleons might be copiously emitted from core-collapse supernovae (SNe). If the axion-nucleon coupling is strong enough, then axions would be emitted from the SN as a burst and, reaching Earth, may excite the oxygen nuclei in water Čherenkov detectors (O16+a→O∗16). This process will be followed by decay(s) of the excited state resulting in an emission of photons and thus providing a possibility for a direct detection of axions from a galactic SN in large underground neutrino Čherenkov detectors. Motivated by this possibility, we present an updated calculation of axion-oxygen cross section obtained by using self-consistent continuum random-phase approximation. We calculate the branching ratio of the oxygen nucleus deexcitation into γ rays, neutrons, protons, and α particles and also consider photon emission from secondary nuclei to compute a total γ spectrum created when axions excite O16. These results are used to revisit the detectability of axions from SN 1987A in Kamiokande-II.Peer reviewe
Axion-like Particles from Hypernovae
It was recently pointed out that very energetic subclasses of supernovae
(SNe), like hypernovae and superluminous SNe, might host ultra-strong magnetic
fields in their core. Such fields may catalyze the production of feebly
interacting particles, changing the predicted emission rates. Here we consider
the case of axion-like particles (ALPs) and show that the predicted large scale
magnetic fields in the core contribute significantly to the ALP production, via
a coherent conversion of thermal photons. Using recent state-of-the-art SN
simulations including magnetohydrodynamics, we find that if ALPs have masses
, their emissivity via magnetic
conversions is over two orders of magnitude larger than previously estimated.
Moreover, the radiative decay of these massive ALPs would lead to a peculiar
delay in the arrival times of the daughter photons. Therefore, high-statistics
gamma-ray satellites can potentially discover MeV ALPs in an unprobed region of
the parameter space and shed light on the magnetohydrodinamical nature of the
SN explosion.Comment: 6 pages, 3 Figure
- …