• • • We do not use the following data for averages, fits, limits, etc. • • • |
$<8.5 \times 10^{-6}$ |
90 |
1 |
|
CNTR |
|
|
2 |
|
RVUE |
$<5.5 \times 10^{-10}$ |
95 |
3 |
|
CNTR |
$<1.2 \times 10^{-6}$ |
95 |
4 |
|
CNTR |
$<2 \times 10^{-4}$ |
90 |
5 |
|
CNTR |
$<1.5 \times 10^{-9}$ |
95 |
6 |
|
CNTR |
$<(0.4 - 10){\times }\text{ 10^}{-3}$ |
95 |
7 |
|
CNTR |
$<(0.2 - 1){\times }\text{ 10^}{-3}$ |
90 |
8 |
|
CNTR |
|
|
9 |
|
CNTR |
$<1.5 \times 10^{-4}$ |
90 |
10 |
|
CNTR |
$<5 \times 10^{-3}$ |
90 |
11 |
|
CNTR |
$<3.4 \times 10^{-5}$ |
95 |
12 |
|
SPEC |
$<4 \times 10^{-4}$ |
95 |
13 |
|
CNTR |
$<3 \times 10^{-3}$ |
95 |
13 |
|
CNTR |
$<0.106$ |
90 |
14 |
|
SPEC |
$<10.8$ |
90 |
14 |
|
SPEC |
$<2.2$ |
90 |
14 |
|
SPEC |
$<4 \times 10^{-4}$ |
90 |
15 |
|
CNTR |
|
|
16 |
|
CNTR |
|
|
17 |
|
CNTR |
|
|
18 |
|
CNTR |
|
|
19 |
|
CNTR |
|
|
20 |
|
CNTR |
|
|
21 |
|
CNTR |
|
|
22 |
|
|
1
DERBIN 2002 looked for the axion emission in an M1 transition in ${}^{125}\mathrm {mTe}$ decay. They looked for a possible presence of a shifted energy spectrum in gamma rays due to the undetected axion.
|
2
DEBOER 1997C reanalyzed the existent data on Nuclear M1 transitions and find that a 9$~$MeV boson decaying into ${{\mathit e}^{+}}{{\mathit e}^{-}}$ would explain the excess of events with large opening angles. See also DEBOER 2001 for follow-up experiments.
|
3
TSUNODA 1995 looked for axion emission when ${}^{252}\mathrm {Cf}$ undergoes a spontaneous fission, with the axion decaying into ${{\mathit e}^{+}}{{\mathit e}^{-}}$ . The bound is for ${\mathit m}_{{{\mathit A}^{0}}}$=40 MeV. It improves to $2.5 \times 10^{-5}$ for ${\mathit m}_{{{\mathit A}^{0}}}$=200 MeV.
|
4
MINOWA 1993 studied chain process, ${}^{139}\mathrm {Ce}$ $\rightarrow$ ${}^{139}\mathrm {La}^{*}$ by electron capture and M1 transition of ${}^{139}\mathrm {La}^{*}$ to the ground state. It does not assume decay modes of ${{\mathit A}^{0}}$. The bound applies for ${\mathit m}_{{{\mathit A}^{0}}}<166$ keV.
|
5
HICKS 1992 bound is applicable for ${\mathit \tau}_{{{\mathit X}^{0}}}$ $<4 \times 10^{-11}$ sec.
|
6
The ASANUMA 1990 limit is for the branching fraction of ${{\mathit X}^{0}}$ emission per ${}^{241}\mathrm {Am}$ ${{\mathit \alpha}}$ decay and valid for ${\mathit \tau}_{{{\mathit X}^{0}}}$ $<$ $3 \times 10^{-11}~$s.
|
7
The DEBOER 1990 limit is for the branching ratio ${}^{8}\mathrm {Be}^{*}$ ($18.15$ MeV, 1${}^{+}$) $\rightarrow$ ${}^{8}\mathrm {Be}$ ${{\mathit A}^{0}}$ , ${{\mathit A}^{0}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ for the mass range ${\mathit m}_{{{\mathit A}^{0}}}$ = 4$-$15 MeV.
|
8
The BINI 1989 limit is for the branching fraction of ${}^{16}\mathrm {O}^{*}$ ($6.05$ MeV, 0${}^{+}$) $\rightarrow$ ${}^{16}\mathrm {O}$ ${{\mathit X}^{0}}$ , ${{\mathit X}^{0}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ for ${\mathit m}_{{{\mathit X}}}$ = $1.5-3.1$ MeV. ${\mathit \tau}_{{{\mathit X}^{0}}}{ {}\lesssim{} }$ $10^{-11}~$s is assumed. The spin-parity of ${{\mathit X}}$ is restricted to 0${}^{+}$ or 1${}^{−}$.
|
9
AVIGNONE 1988 looked for the 1115 keV transition ${}^{}\mathrm {C}^{*}$ $\rightarrow$ ${}^{}\mathrm {Cu}$ ${{\mathit A}^{0}}$ , either from ${{\mathit A}^{0}}$ $\rightarrow$ 2 ${{\mathit \gamma}}$ in-flight decay or from the secondary ${{\mathit A}^{0}}$ interactions by Compton and by Primakoff processes. Limits for axion parameters are obtained for ${\mathit m}_{{{\mathit A}^{0}}}$ $<$ $1.1$ MeV.
|
10
DATAR 1988 rule out light pseudoscalar particle emission through its decay ${{\mathit A}^{0}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ in the mass range $1.02-2.5$ MeV and lifetime range $10^{-13}-10^{-8}~$s. The above limit is for $\tau $ = $5 \times 10^{-13}~$s and $\mathit m$ = $1.7$ MeV; see the paper for the $\tau -\mathit m$ dependence of the limit.
|
11
The limit is for the branching fraction of ${}^{16}\mathrm {O}^{*}$ ($6.05$ MeV, 0${}^{+}$) $\rightarrow$ ${}^{16}\mathrm {O}$ ${{\mathit X}^{0}}$ , ${{\mathit X}^{0}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ against internal pair conversion for ${\mathit m}_{{{\mathit X}^{0}}}$ = $1.7$ MeV and ${\mathit \tau}_{{{\mathit X}^{0}}}$ $<$ $10^{-11}~$s. Similar limits are obtained for ${\mathit m}_{{{\mathit X}^{0}}}$ = $1.3-3.2$ MeV. The spin parity of ${{\mathit X}^{0}}$ must be either 0${}^{+}$ or 1${}^{−}$. The limit at $1.7$ MeV is translated into a limit for the ${{\mathit X}^{0}}$-nucleon coupling constant: $\mathit g{}^{2}_{ {{\mathit X}^{0}} }/4{{\mathit \pi}}$ $<$ $2.3 \times 10^{-9}$.
|
12
The DOEHNER 1988 limit is for ${\mathit m}_{{{\mathit A}^{0}}}$ = $1.7$ MeV, $\tau\mathrm {({{\mathit A}^{0}})}$ $<$ $10^{-10}~$s. Limits less than $10^{-4}$ are obtained for ${\mathit m}_{{{\mathit A}^{0}}}$ = $1.2-2.2$ MeV.
|
13
SAVAGE 1988 looked for ${{\mathit A}^{0}}$ that decays into ${{\mathit e}^{+}}{{\mathit e}^{-}}$ in the decay of the $9.17$ MeV $\mathit J{}^{P}$ = $2{}^{+}{}^{}$ state in ${}^{14}\mathrm {N}$, $17.64$ MeV state $\mathit J{}^{P}$ = $1{}^{+}{}^{}$ in ${}^{8}\mathrm {Be}$, and the $18.15$ MeV state $\mathit J{}^{P}$ = $1{}^{+}{}^{}$ in ${}^{8}\mathrm {Be}$. This experiment constrains the isovector coupling of ${{\mathit A}^{0}}$ to hadrons, if ${\mathit m}_{{{\mathit A}^{0}}}$ = ($1.1$ $\rightarrow$ $2.2$) MeV and the isoscalar coupling of ${{\mathit A}^{0}}$ to hadrons, if ${\mathit m}_{{{\mathit A}^{0}}}$ = ($1.1$ $\rightarrow$ $2.6$) MeV. Both limits are valid only if $\tau\mathrm {({{\mathit A}^{0}})}{ {}\lesssim{} }$ $1 \times 10^{-11}$ s.
|
14
Limits are for $\Gamma\mathrm {({{\mathit A}^{0}}(1.8 MeV))}/\Gamma\mathrm {({{\mathit \pi}}M1)}$; i.e., for 1.8 MeV axion emission normalized to the rate for internal emission of ${{\mathit e}^{+}}{{\mathit e}^{-}}$ pairs. Valid for ${\mathit \tau}_{{{\mathit A}^{0}}}$ $<$ $2 \times 10^{-11}$s. ${}^{6}\mathrm {Li}$ isovector decay data strongly disfavor PECCEI 1986 model I, whereas the ${}^{10}\mathrm {B}$ and ${}^{14}\mathrm {N}$ isoscalar decay data strongly reject PECCEI 1986 model II and III.
|
15
SAVAGE 1986B looked for ${{\mathit A}^{0}}$ that decays into ${{\mathit e}^{+}}{{\mathit e}^{-}}$ in the decay of the 9.17 MeV $\mathit J{}^{P} = 2+$ state in ${}^{14}\mathrm {N}$. Limit on the branching fraction is valid if ${\mathit \tau}_{{{\mathit A}^{0}}}{ {}\lesssim{} }1. \times 10^{-11}$s for ${\mathit m}_{{{\mathit A}^{0}}}$ = (1.1$-$1.7) MeV. This experiment constrains the iso-vector coupling of ${{\mathit A}^{0}}$ to hadrons.
|
16
ANANEV 1985 with IBR-2 pulsed reactor exclude standard ${{\mathit A}^{0}}$ at CL = 95$\%$ masses below 470 keV (${}^{}\mathrm {Li}^{*}$ decay) and below 2${}{\mathit m}_{{{\mathit e}}}$ for deuteron* decay.
|
17
CAVAIGNAC 1983 at Bugey reactor exclude axion at any ${\mathit m}_{\mathrm {{}^{97}\mathrm {Nb}^{*}decay}}$ and axion with ${\mathit m}_{{{\mathit A}^{0}}}$ between 275 and 288 keV (deuteron* decay).
|
18
ALEKSEEV 1982 with IBR-2 pulsed reactor exclude standard ${{\mathit A}^{0}}$ at CL = 95$\%$ mass-ranges ${\mathit m}_{{{\mathit A}^{0}}}$ $<$400 keV (${}^{}\mathrm {Li}^{*}$ decay) and 330 keV $<{\mathit m}_{{{\mathit A}^{0}}}$ $<$2.2 MeV. (deuteron* decay).
|
19
LEHMANN 1982 obtained ${{\mathit A}^{0}}$ $\rightarrow$ 2 ${{\mathit \gamma}}$ rate $<6.2 \times 10^{-5}$/s (CL = 95$\%$) excluding ${\mathit m}_{{{\mathit A}^{0}}}$ between 100 and 1000 keV.
|
20
ZEHNDER 1982 used Gosgen 2.8GW light-water reactor to check ${{\mathit A}^{0}}$ production. No 2${{\mathit \gamma}}$ peak in ${}^{}\mathrm {Li}^{*}$, ${}^{}\mathrm {Nb}^{*}$ decay (both single ${{\mathit p}}$ transition) nor in ${{\mathit n}}$ capture (combined with previous ${}^{}\mathrm {Ba}^{*}$ negative result) rules out standard ${{\mathit A}^{0}}$. Set limit ${\mathit m}_{{{\mathit A}^{0}}}$ $<$60 keV for any ${{\mathit A}^{0}}$.
|
21
ZEHNDER 1981 looked for ${}^{}\mathrm {Ba}^{*}$ $\rightarrow$ ${{\mathit A}^{0}}{}^{}\mathrm {Ba}$ transition with ${{\mathit A}^{0}}$ $\rightarrow$ 2 ${{\mathit \gamma}}$ . Obtained 2${{\mathit \gamma}}$ coincidence rate $<2.2 \times 10^{-5}$/s (CL = 95$\%$) excluding ${\mathit m}_{{{\mathit A}^{0}}}$ $>$160 keV (or 200 keV depending on Higgs mixing). However, see BARROSO 1981 .
|
22
CALAPRICE 1979 saw no axion emission from excited states of carbon. Sensitive to axion mass between 1 and 15 MeV.
|