Limits are on the kinetic mixing parameter $\chi $ which is defined by the Lagrangian $\mathit L$ = $\text{-}{1\over 4}{{\mathit F}}_{{{\mathit \mu}} {{\mathit \nu}}}{{\mathit F}}{}^{{{\mathit \mu}} {{\mathit \nu}}}$ $−{1\over 4}{{\mathit F}}{}^{'}_{{{\mathit \mu}} {{\mathit \nu}}}{{\mathit F}}{}^{'{{\mathit \mu}} {{\mathit \nu}}}$ $\text{-}{\chi \over 2}{{\mathit F}}_{{{\mathit \mu}} {{\mathit \nu}}}{{\mathit F}}{}^{'{{\mathit \mu}} {{\mathit \nu}}}$ + ${{{\mathit m}}{}^{2}_{{{\mathit \gamma}^{\,'}}}\over 2}{{\mathit A}}{}^{'}_{{{\mathit \mu}}}{{\mathit A}}{}^{'{{\mathit \mu}}}$, where ${{\mathit A}_{{{\mu}}}}$ and ${{\mathit A}_{{{\mu}}}^{\,'}}$ are the photon and hidden-photon fields with field strengths ${{\mathit F}}_{{{\mathit \mu}} {{\mathit \nu}}}$ and ${{\mathit F}}{}^{'}_{{{\mathit \mu}} {{\mathit \nu}}}$, respectively, and is the hidden-photon mass.

VALUE CL% DOCUMENT ID TECN  COMMENT • • We do not use the following data for averages, fits, limits, etc. • • $<3 \times 10^{-3}$ 90 1 ABLIKIM 2025 CL   BES3 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 \times 10^{-2} - 0.525$ GeV $<8 \times 10^{-15}$ 90 2 ALBAKRY 2025   CDMS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.2 - 23.3$ eV $<1 \times 10^{-14}$ 95 3 AN 2025   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 \times 10^{-10} - 8 \times 10^{-8}$ eV $<4 \times 10^{-5}$ 90 4 ANDREEV 2025   NA64 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 \times 10^{-3} - 0.4$ GeV $<2 \times 10^{-16}$ 90 5 APRILE 2025 A   XENT ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.01 - 0.4$ keV $>5 \times 10^{-3}$ 90 6 ASWATHI 2025   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 \times 10^{-14} - 1.8 \times 10^{-12}$ eV $<1 \times 10^{-10}$ 95 7 BAUDIS 2025   QRCD ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.1 - 30$ eV $<4 \times 10^{-13}$ 90 8 BLOCH 2025   SNSE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 8$ eV $<7 \times 10^{-10}$ 9 CAPUTO 2025   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.1 - 0.4$ MeV $<1 \times 10^{-6}$ 90 10 CHOI 2025   NEON ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.003 - 3$ MeV $<4 \times 10^{-8}$ 90 11 CORTINA-GIL 2025 A   NA62 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.1 - 1.5$ GeV $<1 \times 10^{-4}$ 90 12 CORTINA-GIL 2025 B   NA62 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.01 - 0.26$ GeV $<1.1 \times 10^{-13}$ 95 13 EGGE 2025   MDMX ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $78.62 - 83.95$ $\mu $eV $<2.3 \times 10^{-13}$ 90 14 LI 2025   PNDX ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.03 - 1$ MeV $<3 \times 10^{-19}$ 95 15 LINDEN 2025   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $90 - 1022$ keV $<0.2$ 95 16 MELO-GALINDO 2025   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $6 \times 10^{-8} - 1 \times 10^{-5}$ eV $<1 \times 10^{-9}$ 17 MIRASOLA 2025   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $2 \times 10^{-13} - 1.4 \times 10^{-12}$ eV $<3 \times 10^{-4}$ 18 ROMERO-JORGE 2025   HION ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.01 - 2$ GeV $<4 \times 10^{-15}$ 95 19 TROST 2025   COSM ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $6 \times 10^{-14} - 4 \times 10^{-13}$ eV $<2 \times 10^{-16}$ 90 20 ZENG 2025   PNDX ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 30$ keV $<8.2 \times 10^{-15}$ 95 21 ZHAO 2025   DM ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $23.4575 - 23.5485$ $\mu $eV $<2.7 \times 10^{-9}$ 95 22 ZHAO 2025 A   DM ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $2 \times 10^{-17} - 3 \times 10^{-14}$ eV $<3 \times 10^{-8}$ 90 23 AAD 2024 AS   ATLS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.01 - 10$ GeV $<3 \times 10^{-5}$ 90 24 ABRATENKO 2024 A   MBNE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.01 - 0.2$ GeV $<4 \times 10^{-6}$ 90 25 ABREU 2024   FASR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ 50 MeV $<0.5 \times 10^{-10}$ 95 26 ADACHI 2024 C   DORR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $41 - 74$ $\mu $eV $<3 \times 10^{-12}$ 90 27 AGOSTINI 2024 A   GRDA ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $65 - 1021$ keV $<4.35 \times 10^{-13}$ 90 28 AGRAWAL 2024   DM ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 24.67 $\mu $eV $<5 \times 10^{-6}$ 90 29 ANDREEV 2024 A   NA64 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.001 - 1$ GeV $<1.8 \times 10^{-3}$ 90 30 ANDREEV 2024 E   NA64 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 \times 10^{-3} - 1$ GeV $<8 \times 10^{-7}$ 95 31 ARAMBURO-GARC.. 2024   CMB ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $3 \times 10^{-15} - 3 \times 10^{-12}$ eV $<1.4 \times 10^{-15}$ 90 32 ARNQUIST 2024   MAJD ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 100$ keV $<1.5 \times 10^{-16}$ 90 33 CERVANTES 2024   SRPH ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 5.35 $\mu $eV $<5 \times 10^{-7}$ 90 34 CORTINA-GIL 2024 A   NA62 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $5 - 500$ MeV $<3 \times 10^{-16}$ 90 35 DOLAN 2024   STAR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.5 - 16$ keV $<3.7 \times 10^{-13}$ 90 36 HE 2024   DM ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 29.5 $\mu $eV $<1 \times 10^{-12}$ 90 37 KNIRCK 2024   BRED ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $44 - 52$ $\mu $eV $<6 \times 10^{-15}$ 95 38 LEVINE 2024   DER ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.21 - 1.24$ $\mu $eV $<1 \times 10^{-6}$ 95 39 LIU 2024   DM ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $2 \times 10^{-2} - 1 \times 10^{4}$ eV $<4.5 \times 10^{-8}$ 95 40 MCCARTHY 2024   CMB ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $10^{-13} - 10^{-11}$ eV $<2.2 \times 10^{-16}$ 90 41 TANG 2024   SHNE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $5.367 - 5.373$ $\mu $eV $<3 \times 10^{-3}$ 95 42 YAN 2024 A   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $3 \times 10^{-18} - 3 \times 10^{-14}$ eV $<1 \times 10^{-3}$ 90 43 AAD 2023 BO   ATLS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $5 - 40$ GeV $<1.3 \times 10^{-8}$ 90 44 AAD 2023 I   ATLS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.017 - 15$ GeV 45 AAD 2023 T   ATLS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}{ {}\lesssim{} }$ 40 GeV $<1 \times 10^{-16}$ 90 46 AALBERS 2023 A   LZ ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 17$ keV $<1.6 \times 10^{-3}$ 90 47 ABLIKIM 2023 AF   BES3 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.5 - 2.9$ GeV 48 ABUDINEN 2023 B   BEL2 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $4 - 9.7$ GeV $<1.61 \times 10^{-14}$ 90 49 ADHIKARI 2023   C100 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 215 eV $<6 \times 10^{-14}$ 90 50 ADHIKARI 2023 A   C100 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $10 - 1000$ keV $<2.1 \times 10^{-3}$ 95 51 ADRIAN 2023   HPS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $19 - 81$ MeV $<1.1 \times 10^{-16}$ 90 52 AGNES 2023 A   DS50 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.03 - 20$ keV $<2 \times 10^{-12}$ 95 53 AN 2023 A   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $4.1 - 6.2$ $\mu $eV $<5 \times 10^{-6}$ 90 54 ANDREEV 2023   NA64 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $10^{-3} - 1.5$ GeV $<5.0 \times 10^{-14}$ 68 55 BAJJALI 2023   BRAS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $49.63 - 74.44$ $\mu $eV $<2 \times 10^{-7}$ 90 56 CORTINA-GIL 2023 C   NA62 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $10 - 700$ MeV $<2.2 \times 10^{-3}$ 90 57 HAYRAPETYAN 2023 G   CMS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.1 - 7.9$ GeV $<3 \times 10^{-11}$ 95 58 KOTAKA 2023   DORR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $74 - 110$ $\mu $eV $<2 \times 10^{-15}$ 59 LI 2023 I   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $10^{-3} - 10^{5}$ eV $<7.9 \times 10^{-13}$ 95 60 RAMANATHAN 2023   QULP ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $19.7 - 30.5$ $\mu $eV $<1.6 \times 10^{-9}$ 95 61 ROMANENKO 2023   LSW ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.21 - 5.7$ $\mu $eV 62 XIA 2023   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}{ {}\lesssim{} }$ $10^{-23}$eV 63 AAD 2022 J   ATLS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 60$ GeV 64 AAD 2022 S   ATLS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}{ {}\lesssim{} }$ 10 GeV $<2 \times 10^{-14}$ 90 65 APRILE 2022   XE1T ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 0.9 keV $<2 \times 10^{-15}$ 90 66 APRILE 2022   XE1T ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.01 - 0.4$ keV $<5 \times 10^{-17}$ 90 67 APRILE 2022 B   XENT ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$= $1 - 39,44 - 140$ keV $<0.01$ 90 68 BATTAGLIERI 2022   BDMP ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $3 - 100$ MeV $(4.6 {}^{+0.5}_{-0.4}) \times 10^{-15}$ 68 69 BOLTON 2022   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = ($8.4$ $\pm0.6$) $ \times 10^{-14}$ eV $<1 \times 10^{-13}$ 90 70 CERVANTES 2022   ORPH ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $65.5 - 69.3$ $\mu $eV $<1 \times 10^{-12}$ 90 71 CHILES 2022   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.7 - 0.8$ eV $<8.7 \times 10^{-11}$ 95 72 HOCHBERG 2022   SNSP ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.73 - 30$ eV 73 LEES 2022   BABR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 \times 10^{-3} - 3.16$ GeV $<7.97 \times 10^{-9}$ 95 74 LU 2022   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}{ {}\lesssim{} }$ $3 \times 10^{-5}$ eV $<6.86 \times 10^{-11}$ 90 75 MANENTI 2022   MDHI ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 1.61 eV $<0.03$ 95 76 THOMAS 2022   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 80$ GeV 77 TUMASYAN 2022 AH   CMS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $4 - 62.5$ GeV 78 TUMASYAN 2022 N   CMS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.6 - 49$ GeV 79 WU 2022 A   PPTA ${\mathit m}_{{{\mathit \gamma}^{\,'}}}{ {}\lesssim{} }$ $10^{-23}$eV $<8 \times 10^{-6}$ 90 80 ANDREEV 2021   NA64 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 \times 10^{-3} - 1$ GeV $<2.3 \times 10^{-4}$ 90 81 ANDREEV 2021 A   NA64 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.1 - 0.35$ GeV $<1.6 \times 10^{-4}$ 95 82 BI 2021   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.03 - 0.06$ eV $<3 \times 10^{-5}$ 90 83 CAZZANIGA 2021   NA64 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $10 - 390$ MeV $<1.68 \times 10^{-15}$ 90 84 DIXIT 2021   CNTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 24.86 $\mu $eV $<2 \times 10^{-16}$ 90 85 GHOSH 2021   RVUE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $2 - 30$ $\mu $eV $<1.8 \times 10^{-13}$ 86 GODFREY 2021   DER ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.2637 - 0.2648$ $\mu $eV $<3 \times 10^{-12}$ 95 87 KOPYLOV 2021 A   CNTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $9 - 40$ eV $<0.02$ 95 88 KRIBS 2021   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}{ {}\lesssim{} }$ 10 GeV 89 SCHMIDT 2021   THEO ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $<$ 0.6 GeV $<3 \times 10^{-8}$ 90 90 TSAI 2021   BDMP ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 0.78 GeV $<1 \times 10^{-4}$ 90 91 AAIJ 2020 C   LHCB ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 214 MeV 92 AAIJ 2020 C   LHCB ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $218 - 315$ MeV 93 ABLIKIM 2020 AB   BES3 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.2 - 2.1$ GeV $<4.1 \times 10^{-12}$ 90 94 AGOSTINI 2020   HPGE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 60 keV $-$ 1 MeV $<3.3 \times 10^{-14}$ 90 95 AMARAL 2020   SCDM ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.2 - 50$ eV $<1.2 \times 10^{-14}$ 90 96 AN 2020   XE1T ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 200 eV $<6.72 \times 10^{-13}$ 95 97 ANDRIANAVALOM.. 2020   FUNK ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.95 - 8.55$ eV $<1 \times 10^{-16}$ 90 98 APRILE 2020   XE1T ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 200$ keV $<9 \times 10^{-16}$ 90 99 ARALIS 2020   SCDM ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.04 - 500$ keV $<3 \times 10^{-5}$ 90 100 ARGUELLES 2020   THEO ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 0.01 GeV $<7 \times 10^{-14}$ 90 101 ARNAUD 2020   EDEL ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 40$ eV $<8.2 \times 10^{-5}$ 90 102 BANERJEE 2020   NA64 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.5 - 24$ MeV $<7 \times 10^{-15}$ 90 103 BARAK 2020   SENS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.2 - 12.8$ eV 104 KRASNIKOV 2020   RVUE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 16.7 MeV $<1.4 \times 10^{-14}$ 90 105 SHE 2020   CDEX ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $10 - 300$ eV $<1.3 \times 10^{-15}$ 90 106 SHE 2020   CDEX ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.1 - 4$ keV $<1 \times 10^{-3}$ 90 107 SIRUNYAN 2020 AQ   CMS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $11.5 - 75$ GeV, $110 - 200$ GeV $<4.3 \times 10^{-10}$ 95 108 TOMITA 2020   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $115.79 - 115.85$ $\mu $eV $<9 \times 10^{-16}$ 90 109 WANG 2020 A   CDEX ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.185 - 10$ keV 110 AABOUD 2019 G   ATLS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $20 - 60$ GeV $<6 \times 10^{-3}$ 90 111 ABLIKIM 2019 A   BES3 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.01 - 2.4$ GeV $<3.4 \times 10^{-3}$ 90 112 ABLIKIM 2019 H   BES3 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.1 - 2.1$ GeV $<8 \times 10^{-15}$ 90 113 AGUILAR-AREVA.. 2019 A   DAMC ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.2 - 30$ eV $<9 \times 10^{-17}$ 90 114 APRILE 2019 D   XE1T ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.186 - 5$ keV $<7.5 \times 10^{-6}$ 90 115 BANERJEE 2019   NA64 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 200$ MeV $<2 \times 10^{-11}$ 116 BHOONAH 2019   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $10^{-22} - 10^{-10}$ eV $<5 \times 10^{-12}$ 95 117 BRUN 2019   SHUK ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $20.8 - 28.3$ $\mu $eV $<4.4 \times 10^{-4}$ 90 118 CORTINA-GIL 2019   NA62 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $60 - 110$ MeV $<3 \times 10^{-5}$ 95 119 DANILOV 2019   TEXO ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 20 eV - 1 MeV $<6 \times 10^{-9}$ 95 120 HOCHBERG 2019   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.8 - 4$ eV $<1 \times 10^{-11}$ 95 121 KOPYLOV 2019   CNTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $9 - 40$ eV $<1.5 \times 10^{-9}$ 122 KOVETZ 2019   COSM ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $10^{-23} - 10^{-13}$ eV $<3 \times 10^{-14}$ 95 123 NGUYEN 2019   WDMX ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 6 neV $-$ 2.07 $\mu $eV $<4.5 \times 10^{-14}$ 90 124 ABE 2018 F   XMAS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $40 - 120$ keV $<2.5 \times 10^{-3}$ 95 125 ADRIAN 2018   HPS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $19 - 81$ MeV $<4.4 \times 10^{-4}$ 90 126 ANASTASI 2018 B   KLOE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $519 - 987$ MeV $<4 \times 10^{-15}$ 90 127 ARMENGAUD 2018   EDE3 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.8 - 500$ keV 128 BANERJEE 2018   NA64 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 23$ MeV $<1.8 \times 10^{-5}$ 90 129 BANERJEE 2018 A   NA64 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 100$ MeV $<1 \times 10^{-8}$ 90 130 KNIRCK 2018   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.67 - 0.92$ meV $<3.1 \times 10^{-14}$ 90 131 ABGRALL 2017   HPGE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 11.8 keV $<6 \times 10^{-4}$ 90 132 ABLIKIM 2017 AA   BES3 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.5 - 3.4$ GeV $<7 \times 10^{-15}$ 90 133 ANGLOHER 2017   CRES ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.3 - 0.7$ keV $<1.2 \times 10^{-4}$ 90 134 BANERJEE 2017   NA64 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.002 - 0.4$ GeV $<2 \times 10^{-11}$ 135 CHANG 2017   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 15 MeV $<4.5 \times 10^{-3}$ 90 136 DUBININA 2017   EMUL ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.1 - 24$ MeV $<4 \times 10^{-4}$ 90 137 LEES 2017 E   BABR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 4.7 GeV 138 AAD 2016 AG   ATLS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.1 - 2$ GeV $<4.4 \times 10^{-4}$ 90 139 ANASTASI 2016   KLOE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $527 - 987$ MeV $<1.7 \times 10^{-6}$ 95 140 KHACHATRYAN 2016   CMS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 2 GeV $<0.04$ 95 141 AAD 2015 CD   ATLS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $15 - 55$ GeV $<1.4 \times 10^{-3}$ 90 142 ADARE 2015   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $30 - 90$ MeV 143 AN 2015 A   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 12 eV - 40 keV 144 ANASTASI 2015   KLOE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 2${\mathit m}_{{{\mathit \mu}}}$ - 1 GeV $<1.7 \times 10^{-3}$ 90 145 ANASTASI 2015 A   KLOE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $5 - 320$ MeV $<4.2 \times 10^{-4}$ 90 146 BATLEY 2015 A   NA48 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 36 MeV 147 JAEGLE 2015   BELL ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.1 - 3.5$ GeV $<3 \times 10^{-13}$ 148 KAZANAS 2015   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 2${\mathit m}_{{{\mathit e}}}$ $-$ 100 MeV $<6 \times 10^{-12}$ 149 SUZUKI 2015   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.9 - 4.3$ eV $<2.3 \times 10^{-13}$ 99.7 150 VINYOLES 2015   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 8 eV $<2 \times 10^{-13}$ 151 ABE 2014 F   XMAS ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $40 - 120$ keV $<1.8 \times 10^{-3}$ 90 152 AGAKISHIEV 2014   HDES ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 63 MeV $<9.0 \times 10^{-4}$ 90 153 BABUSCI 2014   KLOE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 969 MeV 154 BATELL 2014   BDMP ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $10^{-3} - 1$ GeV $<1.3 \times 10^{-7}$ 95 155 BLUEMLEIN 2014   BDMP ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 0.6 GeV $<3 \times 10^{-18}$ 156 FRADETTE 2014   COSM ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $50 - 300$ MeV $<3.5 \times 10^{-4}$ 90 157 LEES 2014 J   BABR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 0.2 GeV $<9 \times 10^{-4}$ 95 158 MERKEL 2014   A1 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $40 - 300$ MeV $<3 \times 10^{-15}$ 159 AN 2013 B   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 2 keV $<7 \times 10^{-14}$ 160 AN 2013 C   XE10 ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 100 eV $<8 \times 10^{-4}$ 161 DIAMOND 2013   BDMP ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $30 - 250$ MeV $<2 \times 10^{-3}$ 90 162 GNINENKO 2013   BDMP ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $25 - 120$ MeV $<2.2 \times 10^{-13}$ 163 HORVAT 2013   HPGE ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 230 eV $<8.06 \times 10^{-5}$ 95 164 INADA 2013   LSW ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 0.04 eV$−$26 keV $<2 \times 10^{-10}$ 95 165 MIZUMOTO 2013   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 1 eV $<1.7 \times 10^{-7}$ 166 PARKER 2013   LSW ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 53 $\mu $eV $<5.32 \times 10^{-15}$ 167 PARKER 2013   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 53 $\mu $eV $<1 \times 10^{-15}$ 168 REDONDO 2013   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 2 keV $<8 \times 10^{-8}$ 90 169 GNINENKO 2012 A   BDMP ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 135$ MeV $<1 \times 10^{-7}$ 90 170 GNINENKO 2012 B   CHRM ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 500$ MeV $<1 \times 10^{-3}$ 90 171 ABRAHAMYAN 2011   ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $175 - 250$ MeV $<9 \times 10^{-8}$ 95 172 BLUEMLEIN 2011   BDMP ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 70 MeV $<1 \times 10^{-7}$ 173 BJORKEN 2009   BDMP ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $2 - 400$ MeV $<5 \times 10^{-9}$ 174 BJORKEN 2009   ASTR ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $2 - 50$ MeV 1  ABLIKIM 2025CL search for kinetically mixed dark photons using the BESIII detector. They use the sample ${{\mathit J / \psi}}$ events collected to measure the transition form factor of the ${{\mathit \eta}}$ meson. Limits are derived on the branching ratio for ${{\mathit \eta}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}^{\,'}}$, ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ and presented in terms of mass-dependent limits on the kinetic mixing parameter in Fig. 7. 2  ALBAKRY 2025 report a search with the SuperCDMS detector for hidden photon dark matter absorption on silicon. See their Fig. 4 for mass-dependent limits. 3  AN 2025 search for dark photon dark matter resonantly converting into photons in the solar corona plasma, leading a signal detectable by the STEREO and Parker Solar Probe spacecraft. See their Fig. 2 for mass-dependent limits. 4  ANDREEV 2025 present the first hidden photon limits from the NA64e experiment using a 70 GeV positron beam. They set constraints on an invisibly decaying hidden photon that kinetically mixes with the photon. See Fig. 14 for various mass-dependent limits, noting the assumed parameter values for the dark gauge coupling and dark matter mass. 5  APRILE 2025A present results from a search with XENONnT for dark photon dark matter absorption on electrons in liquid xenon. See their Fig. 5 for mass-dependent limits. 6  ASWATHI 2025 use LIGO-VIRGO-KAGRA data from the black hole binary merger events GW231123 and GW190517 to search for evidence of the superradiant build-up of a cloud of vector bosons, which could act to spin down the black holes. They set lower limits on the dark photon kinetic mixing and present mass-dependent limits in Fig. 2. 7  BAUDIS 2025 presents results from the QROCODILE experiment which uses a superconducting nanowire single photon detector to search for low-mass dark matter. Fig. 2 shows mass-dependent constraints on hidden photon absorption. 8  BLOCH 2025 present results from a search for single-electron events in the SENSEI low-mass dark matter detector. See their Fig. 4 for mass-dependent limits on dark photon absorption. 9  CAPUTO 2025 present a new bound on dark photon emission from core-collapse supernovae. They consider the cooling effect of resonant dark photon production behind the shock wave which, if too excessive, can potentially prevent the explosion. In the case of SN1987A, this consideration supersedes the standard supernova cooling argument and leads to a bound that is strongest in the sub-MeV mass region. See their Fig. 2 for mass-dependent limits. 10  CHOI 2025 place bounds on a dark matter model using the NEON reactor neutrino experiment. They explore a scenario in which the high flux of photons from the nuclear reactor leads to a flux of dark photons; those dark photons can then decay into dark matter particles in the detector that scatter on electrons. See their Fig. 3 for mass-dependent bounds on the dark photon mediator, obtained for the dark matter mass ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$/3 and the hidden gauge coupling $\alpha _{D}$ = 0.1. 11  CORTINA-GIL 2025A search for kinetically mixed hidden photons decaying to hadronic final states in the NA62 beam dump. Quoted limit applies around 0.8 GeV, but does not extend to arbitrarily large kinetic mixing. See their Fig. 7 for mass-dependent limits combining this hadronic analysis and the dilepton channel reported in CORTINA-GIL 2024A. 12  CORTINA-GIL 2025B report limits on an invisibly decaying dark photon produced in the decays of ${{\mathit K}^{+}}$ and ${{\mathit \pi}^{0}}$ in the NA62 detector. See their Fig. 8 for mass-dependent limits. 13  EGGE 2025 search for dark photon dark matter using the prototype setup of the MADMAX dielectric disk haloscope. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. See their Fig. 4 for mass-dependent limits. 14  LI 2025 search for MeV-mass dark photons making up the dark matter halo of the galaxy that could be absorbed by liquid xenon in the PandaX detector. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. The quoted limit is at ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 150 keV. See their Fig. 3 for mass-dependent limits. 15  LINDEN 2025 extend limits on dark photons as a dark matter candidate at masses below the electron pair creation threshold. They search for evidence of dark photon-to-three-photon decays using data from the INTEGRAL space telescope. See their Fig. 4 for mass-dependent limits. 16  MELO-GALINDO 2025 search for evidence of mixing between standard model and dark photons imprinted on the TeV gamma-ray spectra of the Crab Nebula and gamma-ray source MGRO J1908+06, using data from HAWC and LHAASO. See their Figs. $3 - 6$ for mass-dependent limits for both sources and under various model assumptions. 17  MIRASOLA 2025 search for evidence of superradiant clouds of dark photons surrounding black holes, which are expected to produce pulsating radio emissions, and continuous gravitational wave signals that could be observed by LIGO-Virgo-KAGRA. Their bound disfavours dark photons within a specific range of masses and kinetic mixing parameters between $10^{-9} - 10^{-7}$, subject to uncertainties about the black hole population and details about the cloud's radio emission. See their Fig. 5. 18  ROMERO-JORGE 2025 set limits on kinetically-mixed dark photons produced through various decays in heavy-ion collisions and then decaying to dileptons. They incorporate a range of heavy ion data from across the SIS, RHIC and LHC. They present various mass-dependent limits in their Fig. 7 for different choices for the dark photon "surplus" - the maximum permissible increase in a dilepton yield from dark photons compared to the Standard Model yield. 19  TROST 2025 use VLT/UVES observations of the quasar HE0940-1050 to search for resonant conversion of dark photon dark matter into photons, which would heat the intergalactic medium and imprint on the quasar's Lyman-alpha forest spectrum. See their Fig. 7 for mass-dependent limits. 20  ZENG 2025 place a bound on keV-scale dark photons making up the halo of the galaxy by searching for electron recoil events in the PandaX detector. See Fig. 3(f) for mass-dependent limits. 21  ZHAO 2025 use a flux-tunable resonant cavity to search for dark photon dark matter in a narrow frequency window around 5.69 GHz, performing microwave single photon detection using a transmon qubit. The quoted limit assumes a local dark matter density of $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.45 GeV/cm${}^{3}$ 22  ZHAO 2025A use a single-site, two-sensor array of commercial scalar optically pumped magnetometers to search for dark photon dark matter converting into photons. The relevant observable signal appears in this low-mass regime due to the action of the Earth's ionosphere as transducer. See their Fig. 4 for mass-dependent limits. 23  AAD 2024AS search for hidden photons resulting from Higgs decays in the Falkowski-Ruderman-Volansky-Zupan model. See Fig. 7 for mass-dependent limits, value shown taken from the most constraining point at 10 GeV mass. The limits do not extend to arbitrarily high values of the kinetic mixing, stopping between $10^{-4}$ and $10^{-7}$ at the lower and upper end of the mass range respectively. The limit is also dependent on the branching fraction for Higgs decays resulting in dark photons. 24  ABRATENKO 2024A search for dark trident scattering at a neutrino beam using the MicroBooNE detector. Events involve a pair of particles ${{\mathit \chi}}{{\overline{\mathit \chi}}}$ produced from ${{\mathit \pi}^{0}}$ or ${{\mathit \eta}}$ decays mediated by a dark photon, these particles then scatter off Argon in the detector and can produce an additional dark photon which then decays. See Fig. 7 for mass-dependent limits under three possible scenarios for the ${{\mathit \chi}}$ particle. 25  ABREU 2024 look for hidden photons produced from the ${{\mathit p}}{{\mathit p}}$ collision in the decay channel ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$, and exclude at 90$\%$ CL the region of $\chi $ = $4 \times 10^{-6} - 2 \times 10^{-4}$ and ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $10 - 80$ MeV, with the newly excluded region near the higher values of $\chi $. See their Fig. 7 for mass-dependent limits. 26  ADACHI 2024C follows KOTAKA 2023 of the DOSUE-RR collaboration, searching for hidden photon dark matter conversion using a millimetre-wave receiver and a radioshielding box. See Fig. 11 for mass dependent limits. 27  AGOSTINI 2024A report a search for dark photon dark matter absorption and dark Compton scattering on germanium, generating electron events in the GERDA experiment. The quoted limit is at ${\mathit m}_{{{\mathit A}^{0}}}$ = 150 keV. See their Fig. 7 for mass-dependent limits. 28  AGRAWAL 2024 search for hidden photon dark matter via stimulated emission of a photon from a microwave cavity prepared in a non-classical state by a superconducting qubit. 29  ANDREEV 2024A perform a missing-energy search in the NA64 detector to look for an MeV-scale hidden photon mediator to a stable fermionic dark sector particle. See Fig. 3 for mass-dependent limits. 30  ANDREEV 2024E report results from the NA64$\mu $ beam dump experiment, employing a high-intensity muon beam. They set limits on the kinetic mixing parameter of an invisibly decaying hidden photon. See their Fig. 19 for mass-dependent limits. 31  ARAMBURO-GARCIA 2024 search for evidence of resonant conversion of regular photons into dark photons within the inter-galactic medium using the expected imprint on the CMB anisotropies. Quoted limit is for their "conservative" approach - see their Fig. 5 for mass-dependent limits. 32  ARNQUIST 2024 use the MAJORANA DEMONSTRATOR to search for keV-mass hidden photon dark matter absorption by Germanium. See Fig. 5 for mass-dependent limits. 33  CERVANTES 2024 use a superconducting radio frequency cavity at the SQMS Centre (Fermilab) to search for hidden photon dark matter at 1.3 GHz. See their Fig. 3 for limits in context. 34  CORTINA-GIL 2024A report results from the NA62 beam dump experiment, searching for production and decays of dark photons to lepton pairs. Quoted limit applies around 300 MeV, but does not extend to arbitrarily high kinetic mixing. See their Fig. 4 for mass-dependent limits 35  DOLAN 2024 constrain anomalous cooling of globular cluster stars due to the emission of hidden photons. Best limit is taken from the envelope of limits from the R parameter, R2 parameter and Tip of the Red Giant branch. This study includes hidden photon emission in stellar evolution simulation and so supersedes red giant bound in AN 2020. 36  HE 2024 present results from the APEX collaboration. They look for hidden photon dark matter using a radio frequency cavity at 7.139 GHz. See their Fig. 4 for mass-dependent limits. 37  KNIRCK 2024 search for hidden photon dark matter using GigaBREAD, a broadband haloscope operating at room temperature that uses a parabolic reflector and a horn antenna. See their Fig. 4 for mass-dependent limits. 38  LEVINE 2024 search for hidden photon dark matter using Dark E-Field Radio, a broadband haloscope consisting of an E-field antenna inside a shielded room. This is a continuation of their experiment previously reported in GODFREY 2021. See their Fig. 12 for mass-dependent limits. 39  LIU 2024 constrain hidden photon dark matter over a broad mass range using the very high-energy gamma-ray spectrum of blazars Mrk 501 and Mrk 421. See their Fig. 4 for mass-dependent limits which also depend on the density profiles of the host halos of the blazars. Quoted limit is for the case where the host halos have an NFW profile in Fig. 6. 40  MCCARTHY 2024 search for evidence of photons converting into hidden photons as they traverse large-scale structure, which would lead to a patchy-screening effect observable in CMB anisotropy maps. See their Fig. 3 for mass-dependent limits. This analysis improves upon a similar study by ARAMBURO-GARCIA 2024 - see the note added in MCCARTHY 2024. 41  TANG 2024 present results from a hidden photon dark matter search at 1.3 GHz with SHANHE, a tunable superconducting radio frequency cavity. See their Fig. 3 for mass-dependent limits. 42  YAN 2024A use data from the JUNO probe to constrain hidden photons via the way they would modify Jupiter's magnetic field. See their Fig. 7 for mass-dependent limits. 43  AAD 2023BO look for rare decays of the ${{\mathit Z}}$ boson, ${{\mathit Z}}$ $\rightarrow$ ${{\mathit \gamma}^{\,'}}{+}$ ${{\mathit H}^{\,'}}$, with dark Higgs decaying into a pair of hidden photons, assuming that at least two of the hidden photons decay into ${{\mathit e}^{+}}{{\mathit e}^{-}}$ or ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$. The quoted limit assumes the hidden fine structure constant ${{\mathit \alpha}_{{{D}}}}$ = 0.1 and the dark Higgs mass ranging 20 to 70 GeV. See their Fig.5 for the mass-dependent limits. 44  AAD 2023I look for exotic decays of the SM-like Higgs boson, ${{\mathit H}}$ $\rightarrow$ ${{\mathit \gamma}^{\,'}}{{\mathit \gamma}^{\,'}}$ with hidden photons decaying into displaced lepton or light quark pairs, and set limits on the kinetic mixing within $1 \times 10^{-4} - 1 \times 10^{-8}$ for the given mass range. The quoted limit is for ${\mathit m}_{{{\mathit A}^{0}}}$ $\simeq{}$ 13 GeV with a branching fraction of 0.1 for the Higgs decaying into hidden photon pairs. See their Fig. 13 for the mass-dependent limits. 45  AAD 2023T is analogous to AAD 2022S, but using the ${{\mathit Z}}{{\mathit H}}$ production mode, and set the upper limit on the branching ratio B(${{\mathit H}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}^{\,'}}$) within $0.0219 - 0.0252$ (95$\%$ CL). 46  AALBERS 2023A look for an absorption of hidden photon dark matter. The quoted limit is for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 1.4 keV. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. See their Fig. 7 for mass-dependent limits. 47  ABLIKIM 2023AF look for invisible decays of hidden photons produced in the reaction ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}^{\,'}}$. They set limits within the $1.6 \times 10^{-3} - 5.7 \times 10^{-3}$. See their Fig. 3 for mass-dependent limits. 48  ABUDINEN 2023B look for hidden photons in the dark Higgsstrahlung process, ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \gamma}^{\,'}}{{\mathit H}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$) with ${{\mathit H}^{\,'}}$ being invisible. They set upper limits on the product of the kinetic mixing and the hidden gauge coupling, ${{\mathit \chi}^{2}}\cdot{}{{\mathit \alpha}_{{{D}}}}$, in the range of $1.7 \times 10^{-8} - 2 \times 10^{-6}$ at 90$\%$ CL for a 1 GeV dark Higgs mass. See their Fig. 3 for the mass-dependent limits. 49  ADHIKARI 2023 look for the annual modulation signal induced by solar flux of hidden photons. See their Fig. 10 for mass-dependent limits. 50  ADHIKARI 2023A look for absorption and Compton-like processes of hidden photon dark matter. The quoted limit is for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ 12 keV. Limits between $6 \times 10^{-14} - 3 \times 10^{-11}$ are obtained. See their Fig. 4 for mass-dependent limits. 51  ADRIAN 2023 is an update of ADRIAN 2018, and use the data from the 2016 engineering run at 2.3 GeV. The quoted limit is at ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ 74 MeV. See their Fig. 28 for the mass-dependent limits. 52  AGNES 2023A look for an absorption of hidden photon dark matter. The quoted limit is for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 0.03 keV. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. See their Fig. 2 for mass-dependent limits. 53  AN 2023A look for absorption of hidden photon dark matter at radio telescopes, setting limits based on data from the FAST telescope. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. See their Fig. 1 for mass-dependent limits. 54  ANDREEV 2023 is an update of ANDREEV 2021 and ANDREEV 2021A. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 1 MeV. See their Fig. 3 for mass-dependent limits. 55  BAJJALI 2023 look for hidden photon dark matter by using a $12 - 18$ GHz dish antenna at U. Hamburg that is sensitive to vertically aligned hidden photon polarizations. They assume a local density of $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$. See their Figure 12 for mass-dependent limits in the range of ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $50 - 75$ $\mu eV$ under the assumption of randomly aligned hidden photon polarizations, defined as "1 sigma sensitivity". The run is labelled BRASS-p. 56  CORTINA-GIL 2023C NA62 beam dump experiment searches for hidden photons decaying to ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$, extending their previous search CORTINA-GIL 2019. The quoted limit applies at 300 MeV but does not extend to arbitrarily large kinetic mixing parameters. See Fig. 4 for mass-dependent limits. 57  HAYRAPETYAN 2023G search for kinetically mixed hidden photons in proton-proton collisions at the LHC that would generate a narrow peak in the mass spectrum of dimuon events. The mass window between 2.6 and 4.2 GeV is left unconstrained to avoid ${{\mathit J / \psi}}$ and ${{\mathit \psi}{(2S)}}$ resonances. Mass dependent limits given in their Fig. 6. 58  KOTAKA 2023 is an update of TOMITA 2020, and set limits $\chi $ $<$ $0.3 - 2 \times 10^{-10}$ for the quoted mass range. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.39 GeV/cm${}^{3}$ is assumed. See their Fig. 5 for mass-dependent limits. 59  LI 2023I set cooling bounds on the emission of hidden photons from the Sun, red giant, and horizontal branch stars, including emission of both the transverse and longitudinal modes. Cooling bounds are computed assuming a static model as opposed to considering the impact on stellar evolution. The result is comparable to earlier estimates of the same bound e.g. REDONDO 2013. Limit applies at the most constraining mass around 200 eV for the solar bound. 60  RAMANATHAN 2023 look for hidden photon dark matter using a gold-plated copper dish antenna cooled to 20 mK. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.45 GeV/cm${}^{3}$ is assumed. Limits between $7.9 \times 10^{-13}$ and $3.81 \times 10^{-12}$ are obtained. See their Fig. 5 for mass-dependent limits. 61  ROMANENKO 2023 employed two superconducting radio frequency cavities with a high quality factor, optimized for detecting the longitudinal polarization of the hidden photon. The quoted limit is set at ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ $5\mu $eV. See their Fig. 4 for the mass-dependent limits. 62  XIA 2023 is analogous to WU 2022A and use the Fermi-LAT pulsar timing array. They set a bound on the local density as $\rho _{{{\mathit \gamma}^{\,'}}}{ {}\lesssim{} }$ 7 GeV/cm${}^{3}$ for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ ${ {}\lesssim{} }$ $10^{-23}$ eV at 95$\%$ CL, with weaker constraints up to $10^{-22}$ eV. See their Fig. 1 for the mass-dependent limits. 63  AAD 2022J look for exotic decays of the SM-like Higgs boson, ${{\mathit H}}$ $\rightarrow$ ${{\mathit \gamma}^{\,'}}{{\mathit \gamma}^{\,'}}$ $\rightarrow$ 4 ${{\mathit \ell}}$ and ${{\mathit H}}$ $\rightarrow$ ${{\mathit Z}}{{\mathit \gamma}^{\,'}}$ $\rightarrow$ 4 ${{\mathit \ell}}$, and set limits on the kinetic mixing and the Higgs portal coupling. See their Figs. 19 and 20 for the mass-dependent limits. 64  AAD 2022S look for decays of a Higgs boson into ${{\mathit \gamma}}$ and ${{\mathit \gamma}^{\,'}}$ using the VBF production mode, and set the upper limit on the branching ratio at 0.018 (95$\%$ CL) for the 125 GeV Higgs boson. For the quoted mass range, the signal acceptance changes by less than 1$\%$. 65  APRILE 2022 is analogous to AN 2020, and their limit was corrected in the erratum to this paper: APRILE 2024B. They set limits $\chi $ $<$ $2 \times 10^{-12}$ (eV/${\mathit m}_{{{\mathit \gamma}^{\,'}}}$) for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $<$ 3 eV (90$\%$ C.L.). For ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $>$ 3 eV, see Fig. 1 of APRILE 2024B. 66  APRILE 2022 extend APRILE 2019 to lower masses by removing the background of ionization signals correlated with high-energy events. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 0.09 keV. See their Fig. 15 for mass-dependent limits. 67  APRILE 2022B is an update of APRILE 2020, and set limits $\chi $ ${ {}\lesssim{} }$ $5 \times 10^{-17} - 2 \times 10^{-13}$. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 1 keV. They exclude the XENON1T excess found in APRILE 2020. See their Fig. 6 for mass-dependent limits. 68  BATTAGLIERI 2022 is analogous to BATELL 2014, and derived limits from the electron beam dump experiment at Jefferson Lab (BDX-MINI). Limits at the level of $7 \times 10^{-5} - 1 \times 10^{-2}$ are obtained for the dark matter mass ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$/3 and the hidden gauge coupling $\alpha _{D}$ = 0.1. See their Fig. 11. 69  BOLTON 2022 use the Ly-$\alpha $ forest at z $\simeq{}$ 0.1 as a calorimeter for heating in the intergalactic medium by the resonant conversion of hidden photon dark matter to photons, which is assumed to be responsible for the tension between the predicted and observed Ly-$\alpha $ absorption linewidths. 70  CERVANTES 2022 use a dielectrically loaded Fabry-Perot open cavity to look for hidden photon dark matter. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.45 GeV/cm${}^{3}$ is assumed. See their Fig. 5 for mass-dependent limits. 71  CHILES 2022 look for hidden photon dark matter by using a layered dielectric target and a superconducting nanowire single-photon detector. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.4 GeV/cm${}^{3}$ is assumed. See their Fig. 4 for mass-dependent limits. 72  HOCHBERG 2022 update HOCHBERG 2019. The quoted limit applies to ${\mathit m}_{{{\mathit A}^{0}}}$ $\simeq{}$ 11 eV. See their Fig. 5 for mass-dependent limits. 73  LEES 2022 look for a hidden fermion-fermion bound state decaying into three hidden photons, which subsequently decay into ${{\mathit e}^{+}}{{\mathit e}^{-}}$, ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$, or ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$. For the bound-state mass in the range of $0.05 - 9.5$ GeV, limits at the level of $5 \times 10^{-5} - 1 \times 10^{-3}$ are obtained. See their Fig. 6 for mass-dependent limits. 74  LU 2022 derive the limit by studying the effect of photons oscillating into hidden photons on the surface luminosity of the neutron star RX J1856.6-3754. 75  MANENTI 2022 look for hidden photon dark matter by using a multilayer dielectric haloscope. Limits between $6.86 \times 10^{-11}$ and $5 \times 10^{-8}$ are obtained for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ $1.1 - 3.1$ eV. See their Fig. 11 for mass-dependent limits. 76  THOMAS 2022 improved KRIBS 2021 by taking account of the changes in the parton distribution functions due to the inclusion of hidden photons. The quoted limit is at ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ 4 GeV. Limits in the range of $3 \times 10^{-2} - 9 \times 10^{-2}$ are obtained for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 80$ GeV. See their Fig. 1 for the limits. 77  TUMASYAN 2022AH look for exotic decays of the SM-like Higgs boson, ${{\mathit H}}$ $\rightarrow$ ${{\mathit Z}}{{\mathit \gamma}^{\,'}}$ $\rightarrow$ 4 ${{\mathit \ell}}$, and set limits on the Higgs portal coupling. See their Fig. 6 for the limits. 78  TUMASYAN 2022N look for exotic decays of the SM-like Higgs boson, ${{\mathit H}}$ $\rightarrow$ ${{\mathit \gamma}^{\,'}}{{\mathit \gamma}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$), and set limits on the branching fraction product. See their Fig. 7 for mass- and lifetime-dependent limits. 79  WU 2022A look for direction-dependent oscillations in the gravitational potential generated by ultralight hidden photon dark matter, and set a bound on its local density as $\rho _{{{\mathit \gamma}^{\,'}}}{ {}\lesssim{} }$ 5 GeV/cm${}^{3}$ for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}{ {}\lesssim{} }$ $10^{-23}$ eV at 95$\%$ CL. 80  ANDREEV 2021 is analogous to BANERJEE 2018A. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 1 MeV. See their Fig. 3 for mass-dependent limits. 81  ANDREEV 2021A extends the limits of BANERJEE 2019 by taking account of production through the resonant annihilation of secondary positrons with atomic electrons. The quoted limit is at ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 0.23 GeV, assuming the fermion dark matter of mass ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$/3 and the hidden gauge coupling $\alpha _{D}$ = 0.1. See their Fig.3 for mass-dependent limits. 82  BI 2021 look for the gamma-ray spectral attenuation due to scattering with hidden photons constituting all dark matter, using the measurements of sub-PeV gamma-rays from the Crab Nebula by the Tibet AS${{\mathit \gamma}}$ and HAWC experiments, together with MAGIC and HEGRA gamma-ray data. See their Fig. 4 for mass-dependent limits. 83  CAZZANIGA 2021 look for semi-visible decays of hidden photons, ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit \chi}_{{{1}}}}{{\mathit \chi}_{{{2}}}}$ (${{\mathit \chi}_{{{2}}}}$ $\rightarrow$ ${{\mathit \chi}_{{{1}}}}{{\mathit e}^{+}}{{\mathit e}^{-}}$), where ${{\mathit \chi}_{{{1}}}}$ and ${{\mathit \chi}_{{{2}}}}$ are hidden fermions. They exclude $3 \times 10^{-5}{ {}\lesssim{} }$ $\chi $ ${ {}\lesssim{} }$ $2 \times 10^{-2}$ assuming the hidden gauge coupling ${{\mathit \alpha}_{{{D}}}}$ = 0.1, and the fermion masses ${\mathit m}_{{{\mathit \chi}_{{{1}}}}}$ = ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$/3, (${\mathit m}_{{{\mathit \chi}_{{{2}}}}}$ $−$ ${\mathit m}_{{{\mathit \chi}_{{{1}}}}})/{\mathit m}_{{{\mathit \chi}_{{{1}}}}}$ = 0.4. See their Fig. 4 for mass-dependent limits. 84  DIXIT 2021 look for hidden photon dark matter by using a superconducting transmon qubit dispersively coupled to a high $\mathit Q$ storage cavity. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.4 GeV/cm${}^{3}$ is assumed. See their Fig.4 for mass-dependent limits. 85  GHOSH 2021 use existing haloscope axion search limits to set limits on hidden photon dark matter, considering the polarization of hidden photons. The quoted limit is at ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ 3 $\mu $eV. See their Fig. 1 for mass-dependent limits. 86  GODFREY 2021 look for hidden photon dark matter by using a wideband antenna, and set 5$\sigma $ limits on $\chi $. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.38 GeV/cm${}^{3}$ is assumed. See their updated Fig. 12 in arXiv:2101.02805v4 for mass-dependent limits in the range of ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.207 - 1.24$ $\mu $eV. 87  KOPYLOV 2021A is an update of KOPYLOV 2019, but use ${}^{}\mathrm {Ne}$ gas instead of ${}^{}\mathrm {Ar}$. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 12 eV. See their Fig. 4 for mass-dependent limits. 88  KRIBS 2021 used the HERA data on neutral current deep inelastic ${{\mathit e}}{{\mathit p}}$ scattering to derive the limits, which become weaker for heavier masses. See their Fig. 3 for mass-dependent limits. 89  SCHMIDT 2021 use the microscopic Parton-Hadron-String Dynamics approach to extract limits by comparing the theoretically calculated dilepton spectra with the HADES data on the search for ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$. See their Fig. 5 for the mass-dependent limits for various allowed surplus of the hidden photon contribution over the standard model yield. 90  TSAI 2021 update the limits from the CHARM and NuCal experiments, taking account of additional production channels from proton bremsstrahlung and ${{\mathit \eta}}$ meson decays, respectively. Limits between $3 \times 10^{-8}$ and $1 \times 10^{-4}$ are obtained for 0.01 $<$ ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $<$ 0.8 GeV (see their Fig. 1). 91  AAIJ 2020C look for hidden photons produced from the ${{\mathit p}}{{\mathit p}}$ collision in the decay channel ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$. For prompt decaying hidden photons, limits at the level of $10^{-4} - 10^{-3}$ are obtained for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.214 - 30$ GeV. See their Fig. 2 for mass-dependent limits. 92  AAIJ 2020C look for hidden photons produced from the ${{\mathit p}}{{\mathit p}}$ collision in the decay channel ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$. For hidden photons with lifetimes of order ps, limits at the level of $10^{-5}$ are obtained for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $218 - 315$ MeV. See their Fig. 4 for mass-dependent limits. 93  ABLIKIM 2020AB search for ${{\mathit J / \psi}}$ $\rightarrow$ ${{\mathit \eta}^{\,'}}{{\mathit \gamma}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \pi}^{0}}$), and set the upper limit on the product branching fraction of order $10^{-7}$. See their Fig. 7 for mass-dependent limits. 94  AGOSTINI 2020 is analogous to ABE 2014F. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 150 keV. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. Their limits in their Fig. 3 were later found to be incorrect due to an error of their Eqs. (1) and (2). See Fig. 3 in AGOSTINI 2022A for the corrected limits. 95  AMARAL 2020 use a second-generation SuperCDMS high-voltage eV-resolution detector to set limits on dark-matter hidden photon absorption. The quoted limit is for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ 17 eV. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. See their Fig. 3 for mass-dependent limits. 96  AN 2020 updates the direct detection limit of AN 2013C on solar flux of hidden photons; $\chi $ $<$ $1.6 \times 10^{-12}$ (eV/${\mathit m}_{{{\mathit \gamma}^{\,'}}}$) for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $<$ 6 eV (90$\%$ C.L.). For ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $>$ 6 eV, see their Fig. 1 for mass-dependent limits. 97  ANDRIANAVALOMAHEFA 2020 is analogous to SUZUKI 2015, but uses a mirror that is about one order of magnitude larger than in similar studies in the past. Limits at the level of $10^{-12}$ are obtained for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $2.5 - 7$ eV. See their Fig.23 and Table III for mass-dependent limits. 98  APRILE 2020 is analogous to ABE 2014F, and set limits $\chi $ ${ {}\lesssim{} }$ $10^{-16} - 10^{-12}$. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 1 keV. They also found an excess over known backgrounds, which favors the mass ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $2.3$ $\pm0.2$ keV with a 3 $\sigma $ significance. See their Fig. 10 for mass-dependent limits. 99  ARALIS 2020 is analogous to ABE 2014F. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 0.1 keV. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. The limits at masses above 3 keV in their Fig. 10 was later found to be incorrect due to an error in their analysis. See Fig. 3 in erratum for the corrected limits. 100  ARGUELLES 2020 examine hidden-photon production in atmospheric cosmic-ray showers and its decay in IceCube and Super-Kamiokande. The quoted limit assumes a lifetime of $\mathit c\tau $ = 0.1 km. See their Fig. 16 for mass- and lifetime-dependent limits. 101  ARNAUD 2020 look for the absorption signal of hidden photon dark matter in a ${}^{}\mathrm {Ge}$ detector. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ 9 eV. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. See their Fig. 3 for mass-dependent limits. 102  BANERJEE 2020 is an update of BANERJEE 2018. They exclude $8.2 \times 10^{-5}{ {}\lesssim{} }$ $\chi $ ${ {}\lesssim{} }$ $1 \times 10^{-2}$ for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.5 - 24$ MeV. In particular, they exclude $\chi $ = $1.2 \times 10^{-4} - 6.8 \times 10^{-4}$ for the 16.7 MeV gauge boson. See their Fig. 5 for mass-dependent limits. 103  BARAK 2020 is analogous to AGUILAR-AREVALO 2019A, and look for hidden photon dark matter by using the Skipper CCD. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 12.8 eV. See their Fig. 4 for mass-dependent limits. 104  KRASNIKOV 2020 showed that the limit of BANERJEE 2020 combined with the measured anomalous magnetic moment of the electron exclude the 16.7 MeV gauge boson suggested by the ATOMKI (KRASZNAHORKAY 2016) experiment if it has pure vector or axial-vector interactions. 105  SHE 2020 look for solar hidden photons. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 180 eV. See their Fig. 4 for mass-dependent limits. 106  SHE 2020 look for hidden photon dark matter and set limits $\chi $ $<$ $1.3 \times 10^{-15} - 2.8 \times 10^{-14}$ for the quoted mass range. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. See their Fig. 6 for mass-dependent limits. 107  SIRUNYAN 2020AQ look for a narrow resonance decaying into a pair of muons. For ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $<$ 45 GeV, they use dedicated high-rate dimuon triggers to reduce the muon transverse momentum thresholds. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 50 GeV, and limits of order $10^{-3}$ are obtained for the quoted mass range. See their Fig. 3 for mass-dependent limits. 108  TOMITA 2020 look for hidden photon dark matter using a planar metal plate and cryogenic receiver and set limits $\chi $ $<$ $1.8 - 4.3 \times 10^{-10}$ for the quoted mass range. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.39 GeV/cm${}^{3}$ is assumed. See their Fig. 7 for mass-dependent limits. 109  WANG 2020A is analogous to ABE 2014F. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 185 eV. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. See their Fig. 11 for mass-dependent limits. 110  AABOUD 2019G look for ${{\mathit h}}$ $\rightarrow$ ${{\mathit \gamma}^{\,'}}{{\mathit \gamma}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$) and exclude a kinetic mixing around $10^{-9} - 10^{-8}$ for B(${{\mathit h}}$ $\rightarrow$ ${{\mathit \gamma}^{\,'}}{{\mathit \gamma}^{\,'}}$) = 0.01 and 0.1. See their Fig. 9 for mass-dependent limits. 111  ABLIKIM 2019A look for ${{\mathit J / \psi}}$ $\rightarrow$ ${{\mathit \gamma}^{\,'}}{{\mathit \eta}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$). Limits between $6 \times 10^{-3}$ and $5 \times 10^{-2}$ are obtained (see their Fig. 8). 112  ABLIKIM 2019H look for ${{\mathit J / \psi}}$ $\rightarrow$ ${{\mathit \gamma}^{\,'}}{{\mathit \eta}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$). Limits between $3.4 \times 10^{-3}$ and $2.6 \times 10^{-2}$ are obtained. See their Fig. 5 for mass-dependent limits. 113  AGUILAR-AREVALO 2019A look for the absorption signal of hidden photon dark matter by using a CCD. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 17 eV. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. See their Fig. 4 for mass-dependent limits. 114  APRILE 2019D is analogous to ABE 2014F. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 0.7 keV. See their Fig. 5(f) for mass-dependent limits. 115  BANERJEE 2019 is an update of BANERJEE 2018A. The quoted limit is at ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 1 MeV. See their Fig. 3 for mass-dependent limits. 116  BHOONAH 2019 examine heating of Galactic Center gas clouds by hidden photon dark matter. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ $10^{-12}$ eV. See their Fig. 2 for mass-dependent limits. 117  BRUN 2019 is analogous to SUZUKI 2015. The limit is derived under an assumption that hidden photons constitute the local dark matter density $\rho _{\gamma '}$ = 0.3 GeV/cm${}^{3}$. 118  CORTINA-GIL 2019 look for an invisible hidden photon in the reaction ${{\mathit K}^{+}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{0}}$ (${{\mathit \pi}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}$ ${{\mathit \gamma}^{\,'}}$). The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $62.5 - 65$ MeV. See their Figs. 6 and 7 for mass-dependent limits. 119  DANILOV 2019 examined the hidden photon production in nuclear reactors, correctly taking account of the effective photon mass in the reactor and detector. The limit gets weaker for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ less than the effective photon mass in proportion to 1/${{\mathit m}^{2}}_{{{\mathit \gamma}^{\,'}}}$. See their Fig. 1 for mass-dependent limits. 120  HOCHBERG 2019 look for the absorption signal of hidden photon dark matter by using superconducting-nanowire single-photon detectors. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ 1 eV. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. See their Fig. 4 for mass-dependent limits. 121  KOPYLOV 2019 look for hidden-photon dark matter using a counter with an aluminum cathode and derive limits assuming it constitute all the local dark matter. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 12 eV. See their Fig. 7 for mass-dependent limits. 122  KOVETZ 2019 examine heating of the early Universe plasma by hidden photon dark matter, and derive the limits by requiring that the cosmic mean 21 cm brightness temperature relative to the CMB temperature satisfy T$_{21}$ $>$ $-100$ mK. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ $2 \times 10^{-14}$ eV. See their Fig. 3 for mass-dependent limits. 123  NGUYEN 2019 look for hidden photon dark matter with a resonant cavity, and set limits $\sim{}10^{-12}$ for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.2 - 2.07\mu $eV. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 1.3 $\mu $eV. The local density $\rho _{{{\mathit \gamma}^{\,'}}}$ = 0.3 GeV/cm${}^{3}$ is assumed. See their Fig. 19 for mass-dependent limits. 124  ABE 2018F is an update of ABE 2014F. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ 40 keV. See their Fig. 5 for mass-dependent limits. 125  ADRIAN 2018 look for a hidden photon resonance in the reaction ${{\mathit e}^{-}}$ ${{\mathit Z}}$ $\rightarrow$ ${{\mathit e}^{-}}{{\mathit Z}}{{\mathit \gamma}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$). The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 40 MeV. See their Fig. 4 for mass-dependent limits. 126  ANASTASI 2018B look for a hidden photon resonance in the reaction ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \gamma}^{\,'}}{{\mathit \gamma}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$). The quoted limit is obtained by combining the result of ANASTASI 2016 and it applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $\simeq{}$ $519 - 987$ MeV. See their Fig. 9 for mass-dependent limits. 127  ARMENGAUD 2018 is analogous to ABE 2014F. The quoted limits applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 1.6 keV. See the right panel of Fig. 5 for mass-dependent limits. 128  BANERJEE 2018 look for hidden photons produced in the reaction ${{\mathit e}^{-}}$ ${{\mathit Z}}$ $\rightarrow$ ${{\mathit e}^{-}}{{\mathit Z}}{{\mathit \gamma}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$), and exclude $9.2 \times 10^{-5}{ {}\lesssim{} }$ $\chi $ ${ {}\lesssim{} }$ $1 \times 10^{-2}$ for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1 - 23$ MeV. They also set a limit on the electron coupling to a 16.7 MeV gauge boson suggested by the ATOMKI (KRASZNAHORKAY 2016) experiment. See their Fig. 3 for mass-dependent limits. 129  BANERJEE 2018A look for invisible decays of hidden photons produced in the reaction ${{\mathit e}^{-}}$ ${{\mathit Z}}$ $\rightarrow$ ${{\mathit e}^{-}}{{\mathit Z}}{{\mathit \gamma}^{\,'}}$ . The quoted limit is at ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 1 MeV. See their Fig. 15 for mass-dependent limits. 130  KNIRCK 2018 is analogous to SUZUKI 2015. See their Fig. 5 for mass-dependent limits. 131  ABGRALL 2017 is analogous to ABE 2014F using the MAJORANA DEMONSTRATOR. See their Fig. 3 for limits between 6 keV $<$ ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $<$ 97 keV. 132  ABLIKIM 2017AA look for ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ or ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$). Limits between $10^{-3}$ and $10^{-4}$ are obtained (see their Fig. 3). 133  ANGLOHER 2017 is analogous to ABE 2014F. The quoted limit is at ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 0.7 keV. See their Fig. 8 for mass-dependent limits. 134  BANERJEE 2017 look for invisible decays of hidden photons produced in the reaction ${{\mathit e}^{-}}$ ${{\mathit Z}}$ $\rightarrow$ ${{\mathit e}^{-}}{{\mathit Z}}{{\mathit \gamma}^{\,'}}$. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 2 MeV. See their Fig. 3 for mass-dependent limits. 135  CHANG 2017 examine the hidden photon emission from SN1987A, including the effects of finite temperature and density on $\chi $ and obtain limits $\chi $ (${\mathit m}_{{{\mathit \gamma}^{\,'}}}$/MeV) ${ {}\lesssim{} }$ $3 \times 10^{-9}$ for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $<$ 15 MeV and $\chi $ ${ {}\lesssim{} }$ $10^{-9}$ for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $15 - 120$ MeV. 136  DUBININA 2017 look for ${{\mathit \mu}^{+}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\overline{\mathit \nu}}_{{{\mu}}}}{{\mathit \nu}_{{{e}}}}{{\mathit \gamma}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$) in a nuclear photoemulsion. The quoted limit applies to ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 1.1 MeV. Limits between $4.5 \times 10^{-3}$ and $10^{-2}$ are obtained (see their Fig. 3). 137  LEES 2017E look for invisible decays of hidden photons produced in the reaction ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}^{\,'}}$. See their Fig. 5 for limits in the mass range ${\mathit m}_{{{\mathit \gamma}^{\,'}}}{}\leq{}$ 8 GeV. 138  AAD 2016AG look for hidden photons promptly decaying into collimated electrons and/or muons, assuming that they are produced in the cascade decays of squarks or the Higgs boson. See their Fig. 10 and Fig.13 for their limits on the cross section times branching fractions. 139  ANASTASI 2016 look for the decay ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit \pi}^{+}}$ ${{\mathit \pi}^{-}}$ in the reaction ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}^{\,'}}$. Limits between $4.3 \times 10^{-3}$ and $4.4 \times 10^{-4}$ are obtained for 527 $<$ ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $<$ 987 MeV (see their Fig. 9). 140  KHACHATRYAN 2016 look for ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$ in a dark SUSY scenario where the SM-like Higgs boson decays into a pair of the visible lightest neutralinos with mass 10 GeV, both of which decay into ${{\mathit \gamma}^{\,'}}$ and a hidden neutralino with mass 1 GeV. See the right panel in their Fig. 2. 141  AAD 2015CD look for ${{\mathit H}}$ $\rightarrow$ ${{\mathit Z}}{{\mathit \gamma}^{\,'}}$ $\rightarrow$ 4 ${{\mathit \ell}}$ with the ATLAS detector at LHC and find $\chi $ $<$ $4 - 17 \times 10^{-2}$ for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $15 - 55$ GeV. See their Fig. 6. 142  ADARE 2015 look for a hidden photon in ${{\mathit \pi}^{0}}$, ${{\mathit \eta}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit e}^{+}}{{\mathit e}^{-}}$ at the PHENIX experiment. See their Fig. 4 for mass-dependent limits. 143  AN 2015A derived limits from the absence of ionization signals in the XENON10 and XENON100 experiments, assuming hidden photons constitute all the local dark matter. Their best limit is $\chi $ $<$ $1.3 \times 10^{-15}$ at ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = 18 eV. See their Fig. 1 for mass-dependent limits. 144  ANASTASI 2015 look for a production of a hidden photon and a hidden Higgs boson with the KLOE detector at DA$\Phi $NE, where the hidden photon decays into a pair of muons and the hidden Higgs boson lighter than ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ escape detection. See their Figs. 6 and 7 for mass-dependent limits on a product of the hidden fine structure constant and the kinetic mixing. 145  ANASTASI 2015A look for the decay ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ in the reaction ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}{{\mathit \gamma}}$. Limits between $1.7 \times 10^{-3}$ and $1 \times 10^{-2}$ are obtained for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $5 - 320$ MeV (see their Fig. 7). 146  BATLEY 2015A look for ${{\mathit \pi}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$) at the NA48/2 experiment. Limits between $4.2 \times 10^{-4}$ and $8.8 \times 10^{-3}$ are obtained for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $9 - 120$ MeV (see their Fig. 4). 147  JAEGLE 2015 look for the decay ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$, ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$, or ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ in the dark Higgstrahlung channel, ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \gamma}^{\,'}}{{\mathit H}^{\,'}}$ (${{\mathit H}^{\,'}}$ $\rightarrow$ ${{\mathit \gamma}^{\,'}}{{\mathit \gamma}^{\,'}}$) at the BELLE experiment. They set limits on a product of the branching fraction and the Born cross section as well as a product of the hidden fine structure constant and the kinetic mixing. See their Figs. 3 and 4. 148  KAZANAS 2015 set limits by studying the decay of hidden photons ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ inside and near the progenitor star of SN1987A. See their Fig. 6 for mass-dependent limits. 149  SUZUKI 2015 looked for hidden-photon dark matter with a dish antenna and derived limits assuming they constitute all the local dark matter. Their limits are $\chi $ $<$ $6 \times 10^{-12}$ for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $1.9 - 4.3$ eV. See their Fig. 7 for mass-dependent limits. 150  VINYOLES 2015 performed a global fit analysis based on helioseismology and solar neutrino observations, and set the limits $\chi {\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $<$ $1.8 \times 10^{-12}$ eV for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $3 \times 10^{-5} - 8$ eV. See their Fig. 11. 151  ABE 2014F look for the photoelectric-like interaction in the XMASS detector assuming the hidden photon constitutes all the local dark matter. Limits between $2 \times 10^{-13}$ and $1 \times 10^{-12}$ are obtained, where the relation $\chi {}^{2}$ = $\alpha $'/$\alpha $ is used to translate the original bound on the ratio of the hidden and EM fine-structure constants. See their Fig. 3 for mass-dependent limits. 152  AGAKISHIEV 2014 look for hidden photons ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ at the HADES experiment, and set limits on ${{\mathit \chi}}$ for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $0.02 - 0.6$ GeV. See their Fig. 5 for mass-dependent limits. 153  BABUSCI 2014 look for the decay ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit \mu}^{+}}$ ${{\mathit \mu}^{-}}$ in the reaction ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}{{\mathit \gamma}}$. Limits between $4 \times 10^{-3}$ and $9.0 \times 10^{-4}$ are obtained for 520 MeV $<$ ${\mathit m}_{{{\mathit \gamma}^{\,'}}}<$ 980 MeV (see their Fig. 7). 154  BATELL 2014 derived limits from the electron beam dump experiment at SLAC (E-137) by searching for events with recoil electrons by sub-GeV dark matter produced from the decay of the hidden photon. Limits at the level of $10^{-4} - 10^{-1}$ are obtained for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ = $10^{-3} - 1$ GeV, depending on the dark matter mass and the hidden gauge coupling (see their Fig. 2). 155  BLUEMLEIN 2014 analyzed the beam dump data taken at the U-70 accelerator to look for ${{\mathit \gamma}^{\,'}}$-bremsstrahlung and the subsequent decay into muon pairs and hadrons. See their Fig. 4 for mass-dependent excluded region. 156  FRADETTE 2014 studied effects of decay of relic hidden photons on BBN and CMB to set constraints on very small values of the kinetic mixing. See their Figs. 4 and 7 for mass-dependent excluded regions. 157  LEES 2014J look for hidden photons in the reaction ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$, ${{\mathit \mu}^{+}}$ ${{\mathit \mu}^{-}}$). Limits at the level of $10^{-4} - 10^{-3}$ are obtained for 0.02 GeV $<$ ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $<$ 10.2 GeV. See their Fig. 4 for mass-dependent limits. 158  MERKEL 2014 look for ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ at the A1 experiment at the Mainz Microtron (MAMI). See their Fig. 3 for mass-dependent limits. 159  AN 2013B examined the stellar production of hidden photons, correcting an important error of the production rate of the longitudinal mode which now dominates. See their Fig. 2 for mass-dependent limits based on solar energy loss. 160  AN 2013C use the solar flux of hidden photons to set a limit on the atomic ionization rate in the XENON10 experiment. They find $\chi $ ${\mathit m}_{{{\mathit \gamma}^{\,'}}}$ $<$ $3 \times 10^{-12}$ eV for ${\mathit m}_{{{\mathit \gamma}^{\,'}}}<$ 1 eV. See their Fig. 2 for mass-dependent limits. 161  DIAMOND 2013 analyzed the beam dump data taken at the SLAC millicharge experiment to constrain a hidden photon invisibly decaying into lighter long-lived particles, which undergo elastic scattering off nuclei in the detector. Limits between $8 \times 10^{-4} - 2 \times 10^{-2}$ are obtained. The quoted limit is applied when the dark gauge coupling is set equal to the electromagnetic coupling. See their Fig.4 for mass-dependent limits. 162  GNINENKO 2013 used the data taken at the SINDRUM experiment to constrain the decay, ${{\mathit \pi}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$) to derive limits. See their Fig. 2 for their mass-dependent excluded region. 163  HORVAT 2013 look for hidden-photo-electric effect in HPGe detectors induced by solar hidden photons. See their Fig. 3 for mass-dependent limits. 164  INADA 2013 search for hidden photons using an intense X-ray beamline at SPring-8. See their Fig. 4 for mass-dependent limits. 165  MIZUMOTO 2013 look for solar hidden photons. See their Fig. 5 for mass-dependent limits. 166  PARKER 2013 look for hidden photons using a cryogenic resonant microwave cavity. See their Fig.5 for mass-dependent limits. 167  PARKER 2013 derived a limit for the hidden photon CDM with a randomly oriented hidden photon field. 168  REDONDO 2013 examined the solar emission of hidden photons including the enhancement factor for the longitudinal mode pointed out by AN 2013B, and also updated stellar-energy loss arguments. See their Fig.3 for mass-dependent limits, including a review of the currently best limits from other arguments. 169  GNINENKO 2012A obtained bounds on B(${{\mathit \pi}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}^{\,'}}$) $\cdot{}$ B(${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$) from the NOMAD and PS191 neutrino experiments, and derived limits between $8 \times 10^{-8} - 2 \times 10^{-4}$. See their Fig.4 for mass-dependent excluded regions. 170  GNINENKO 2012B used the data taken at the CHARM experiment to constrain the decay, ${{\mathit \eta}}({{\mathit \eta}^{\,'}}$) $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$), and derived limits between $1 \times 10^{-7} - 1 \times 10^{-4}$. See their Fig.4 for mass-dependent excluded region. 171  ABRAHAMYAN 2011 look for ${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$ in the electron-nucelon fixed-target experiment at the Jefferson Laboratory (APEX). See their Fig. 5 for mass-dependent limits. 172  BLUEMLEIN 2011 analyzed the beam dump data taken at the U-70 accelerator to look for ${{\mathit \pi}^{0}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}^{\,'}}$ (${{\mathit \gamma}^{\,'}}$ $\rightarrow$ ${{\mathit e}^{+}}{{\mathit e}^{-}}$). See their Fig. 5 for mass-dependent limits. 173  BJORKEN 2009 analyzed the beam dump data taken at E137, E141, and E774 to constrain a hidden photon produced by bremsstrahlung, subsequently decaying into ${{\mathit e}^{+}}{{\mathit e}^{-}}$, and derived limits between $10^{-7}$ and $10^{-2}$. See their Fig. 1 for mass-dependent excluded region. 174  BJORKEN 2009 required the energy loss in the ${{\mathit \gamma}^{\,'}}$ emission from the core of SN1987A not to exceed $10^{53}$ erg/s, and derived limits between $5 \times 10^{-9}$ and $2 \times 10^{-6}$. See their Fig. 1 for mass-dependent excluded region.

References