Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userDirect search for solar axions by using strong magnetic field and X-ray detectors
342
0
0.0
(
0
)
Authors
Shigetaka Moriyama
Ask ChatGPT about the research
No Arabic abstract
We have searched for axions which could be produced in the solar core by exploiting their conversion to X rays in a strong laboratory magnetic field. The signature of the solar axion is an increase in the rate of the X rays detected in a magnetic helioscope when the sun is within its acceptance. From the absence of such a signal we set a 95% confidence level limit on the axion coupling to two photons $g_{agammagamma}equiv 1/M < 6.0times 10^{-10}$ GeV$^{-1}$, provided the axion mass $m_a<0.03$ eV. The limit on the coupling is factor 4.5 more stringent than the recent experimental result. This is the first experiment whose sensitivity to $g_{agammagamma}$ is higher than the limit constrained by the solar age consideration.
rate research
Read More
The results of a search for solar axions from the Korea Invisible Mass Search (KIMS) experiment at the Yangyang Underground Laboratory are presented. Low-energy electron-recoil events would be produced by conversion of solar axions into electrons via the axio-electric effect in CsI(Tl) crystals. Using data from an exposure of 34,596 $rm kg cdot days$, we set a 90 % confidence level upper limit on the axion-electron coupling, $g_{ae}$, of $1.39 times 10^{-11}$ for an axion mass less than 1 keV/$rm c^2$. This limit is lower than the indirect solar neutrino bound, and fully excludes QCD axions heavier than 0.48 eV/$rm c^2$ and 140.9 eV/$rm c^2$ for the DFSZ and KSVZ models respectively.
A search for resonant absorption of the solar axion by $^{83}rm{Kr}$ nuclei was performed using the proportional counter installed inside the low-background setup at the Baksan Neutrino Observatory. The obtained model independent upper limit on the combination of isoscalar and isovector axion-nucleon couplings $|g_3-g_0|leq 8.4times 10^{-7}$ allowed us to set the new upper limit on the hadronic axion mass of $m_{A}leq 65$ eV (95% C.L.) with the generally accepted values $S$=0.5 and $z$=0.56.
A search for axioelectric absorption of solar axions produced in the $ p + d rightarrow {^3rm{He}}+gamma~(5.5~ rm{MeV})$ reactions has been performed with a BGO detector placed in a low-background setup. A model-independent limit on an axion-nucleon and axion-electron coupling constant has been obtained: $| g_{Ae}times g_{AN}^3|< 1.9times 10^{-10}$ for 90% confidence level. The constrains of the axion-electron coupling have been obtained for hadronic axion with masses in (0.1 - 1) MeV range: $|g_{Ae}| leq (0.96 - 8.2)times 10^{-8}$.
We have searched for hadronic axions which may be produced in the Sun by a bremsstrahlung-like process, and observed in the HPGe detector by an axioelectric effect. A conservative upper limit on the hadronic axion mass m_a < 334 eV at 95% C.L. is obtained. Our experimental approach is based on the axion-electron coupling and it does not include the axion-nucleon coupling, which suffers from the large uncertainties related to the estimation of the flavor-singlet axial-vector matrix element.
We have started the development of a detector system, sensitive to single photons in the eV energy range, to be suitably coupled to one of the CAST magnet ports. This system should open to CAST a window on possible detection of low energy Axion Like Particles emitted by the sun. Preliminary tests have involved a cooled photomultiplier tube coupled to the CAST magnet via a Galileian telescope and a switched 40 m long optical fiber. This system has reached the limit background level of the detector alone in ideal conditions, and two solar tracking runs have been performed with it at CAST. Such a measurement has never been done before with an axion helioscope. We will present results from these runs and briefly discuss future detector developments.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
