${}^{8}\mathrm {B}$ solar-neutrino flux measured via ${{\mathit \nu}}{{\mathit e}}$ elastic scattering. This process is sensitive to all active neutrino flavors, but with reduced sensitivity to ${{\mathit \nu}_{{\mu}}}$, ${{\mathit \nu}_{{\tau}}}$ due to the cross-section difference, $\sigma\mathrm {( {{\mathit \nu}} _{{{\mathit \mu}}, {{\mathit \tau}}} {{\mathit e}} )}$ $\sim{}0.16\sigma\mathrm {( {{\mathit \nu}_{{e}}} {{\mathit e}} )}$. If the ${}^{8}\mathrm {B}$ solar-neutrino flux involves nonelectron flavor active neutrinos, their contribution to the flux is $\sim{}0.16$ times of ${{\mathit \nu}_{{e}}}$.

VALUE ($ 10^{6} $ cm${}^{-2}$s${}^{-1}$) DOCUMENT ID TECN  COMMENT • • We do not use the following data for averages, fits, limits, etc. • • $2.57$ ${}^{+0.17}_{-0.18}$ ${}^{+0.07}_{-0.07}$ 1 AGOSTINI 2020 A BORX average flux $2.53$ ${}^{+0.31}_{-0.28}$ ${}^{+0.13}_{-0.10}$ 2 ANDERSON 2019 SNO+ Water phase; average flux $2.57$ ${}^{+0.17}_{-0.18}$ ${}^{+0.07}_{-0.07}$ 3 AGOSTINI 2018 B BORX average flux $2.345$ $\pm0.014$ $\pm0.036$ 4 ABE 2016 C SKAM SK-I+II+III+IV average flux $2.308$ $\pm0.020$ ${}^{+0.039}_{-0.040}$ 5 ABE 2016 C SKAM SK-IV average flux $2.250$ ${}^{+0.030}_{-0.029}$ $\pm0.038$ 5 ABE 2016 C SKAM SK-IV day flux $2.364$ $\pm0.029$ $\pm0.040$ 5 ABE 2016 C SKAM SK-IV night flux $2.404$ $\pm0.039$ $\pm0.053$ 6 ABE 2016 C SKAM SK-III average flux $2.41$ $\pm0.05$ ${}^{+0.16}_{-0.15}$ 7 ABE 2011 SKAM SK-II average flux $2.38$ $\pm0.02$ $\pm0.08$ 8 ABE 2011 SKAM SK-I average flux $2.77$ $\pm0.26$ $\pm0.32$ 9 ABE 2011 B KLND average flux $2.4$ $\pm0.4$ $\pm0.1$ 10 BELLINI 2010 A BORX average flux $1.77$ ${}^{+0.24}_{-0.21}$ ${}^{+0.09}_{-0.10}$ 11 AHARMIM 2008 SNO Phase III $2.38$ $\pm0.05$ ${}^{+0.16}_{-0.15}$ 12 CRAVENS 2008 SKAM average flux $2.35$ $\pm0.02$ $\pm0.08$ 13 HOSAKA 2006 SKAM average flux $2.35$ $\pm0.22$ $\pm0.15$ 14 AHARMIM 2005 A SNO Salty D$_{2}$O; ${}^{8}\mathrm {B}$ shape not constrained $2.34$ $\pm0.23$ ${}^{+0.15}_{-0.14}$ 14 AHARMIM 2005 A SNO Salty D$_{2}$O; ${}^{8}\mathrm {B}$ shape constrained $2.39$ ${}^{+0.24}_{-0.23}$ $\pm0.12$ 15 AHMAD 2002 SNO average flux $2.39$ $\pm0.34$ ${}^{+0.16}_{-0.14}$ 16 AHMAD 2001 SNO average flux $2.80$ $\pm0.19$ $\pm0.33$ 17 FUKUDA 1996 KAMI average flux $2.70$ $\pm0.27$ 17 FUKUDA 1996 KAMI day flux $2.87$ ${}^{+0.27}_{-0.26}$ 17 FUKUDA 1996 KAMI night flux 1  AGOSTINI 2020A obtained this result from the ${{\mathit \nu}_{{e}}}{{\mathit e}}$ elastic scattering rate over the period between January 2008 and December 2016. Uses the same data as AGOSTINI 2018B, but the analysis technique is significantly improved. 2  ANDERSON 2019 reports this result from the ${{\mathit \nu}_{{e}}}{{\mathit e}}$ elastic scattering rate using a 69.2 kton$\cdot{}$day (or 114.7 days) of exposure from May through December, 2017 during the SNO+ detector's water commissioning phase. The events over the reconstructed electron kinetic energy range of $5 - 15$ MeV were analyzed. 3  AGOSTINI 2018B obtained this result from the ${{\mathit \nu}_{{e}}}{{\mathit e}}$ elastic scattering rate over the period between January 2008 and December 2016. 4  ABE 2016C reports the combined results of the four phases of the Super-Kamiokande average flux measurements. Here the revised Super-Kamiokande-III result is used. 5  ABE 2016C reports the Super-Kamiokande-IV results for 1664 live days from September 2008 to February 2014. The analysis threshold is total electron energy of 4.0 MeV. 6  ABE 2016C revised the Super-Kamiokande-III average flux value reported in ABE 2011 . Super-Kamiokande-III results are for 548 live days from August 4, 2006 to August 18, 2008. The analysis threshold is 5.0 MeV, but the event sample in the $5.0 - 6.5$ MeV total electron energy range has a total live time of 298 days. 7  ABE 2011 recalculated the Super-Kamiokande-II results using ${}^{8}\mathrm {B}$ spectrum of WINTER 2006A. 8  ABE 2011 recalculated the Super-Kamiokande-I results using ${}^{8}\mathrm {B}$ spectrum of WINTER 2006A. 9  ABE 2011B use a 123 kton$\cdot{}$day exposure of the KamLAND liquid scintillation detector to measure the ${}^{8}\mathrm {B}$ solar neutrino flux. They utilize ${{\mathit \nu}}−{{\mathit e}}$ elastic scattering above a reconstructed-energy threshold of 5.5 MeV, corresponding to 5 MeV electron recoil energy. 299 electron recoil candidate events are reported, of which $157$ $\pm23.6$ are assigned to background. 10  BELLINI 2010A reports the Borexino result with 3 MeV energy threshold for scattered electrons. The data correspond to 345.3 live days with a target mass of 100 t, between July 15, 2007 and August 23, 2009. 11  AHARMIM 2008 reports the results from SNO Phase III measurement using an array of ${}^{3}\mathrm {He}$ proportional counters to measure the rate of NC interactions in heavy water, over the period between November 27, 2004 and November 28, 2006, corresponding to 385.17 live days. A simultaneous fit was made for the number of NC events detected by the proportional counters and the numbers of NC, CC, and ES events detected by the PMTs, where the spectral distributions of the ES and CC events were not constrained to the ${}^{8}\mathrm {B}$ shape. 12  CRAVENS 2008 reports the Super-Kamiokande-II results for 791 live days from December 2002 to October 2005. The photocathode coverage of the detector is 19$\%$ (reduced from 40$\%$ of that of Super-Kamiokande-I due to an accident in 2001). The analysis threshold for the average flux is 7 MeV. 13  HOSAKA 2006 reports the final results for 1496 live days with Super-Kamiokande-I between May 31, 1996 and July 15, 2001, and replace FUKUDA 2002 results. The analysis threshold is 5 MeV except for the first 280 live days (6.5 MeV). 14  AHARMIM 2005A measurements were made with dissolved NaCl (0.195$\%$ by weight) in heavy water over the period between July 26, 2001 and August 28, 2003, corresponding to 391.4 live days, and update AHMED 2004A. The $\mathit CC$, $\mathit ES$, and $\mathit NC$ events were statistically separated. In one method, the ${}^{8}\mathrm {B}$ energy spectrum was not constrained. In the other method, the constraint of an undistorted ${}^{8}\mathrm {B}$ energy spectrum was added for comparison with AHMAD 2002 results. 15  AHMAD 2002 reports the ${}^{8}\mathrm {B}$ solar-neutrino flux measured via ${{\mathit \nu}}{{\mathit e}}$ elastic scattering above the kinetic energy threshold of 5$~$MeV. The data correspond to 306.4 live days with SNO between November 2, 1999 and May 28, 2001, and updates AHMAD 2001 results. 16  AHMAD 2001 reports the ${}^{8}\mathrm {B}$ solar-neutrino flux measured via ${{\mathit \nu}}{{\mathit e}}$ elastic scattering above the kinetic energy threshold of $6.75$ MeV. The data correspond to 241 live days with SNO between November 2, 1999 and January 15, 2001. 17  FUKUDA 1996 results are for a total of 2079 live days with Kamiokande$~$II and III from January 1987 through February 1995, covering the entire solar cycle$~$22, with threshold E$_{{{\mathit e}}}>9.3~$MeV (first 449 days), $>7.5~$MeV (middle 794 days), and $>7.0~$MeV (last 836 days). These results update the HIRATA 1990 result for the average ${}^{8}\mathrm {B}$ solar-neutrino flux and HIRATA 1991 result for the day-night variation in the ${}^{8}\mathrm {B}$ solar-neutrino flux. The total data sample was also analyzed for short-term variations: within experimental errors, no strong correlation of the solar-neutrino flux with the sunspot numbers was found.

References:

AGOSTINI 2020A PR D101 062001 Improved measurement of $^8$B solar neutrinos with $1.5 kt·y$ of Borexino exposure ANDERSON 2019 PR D99 012012 Measurement of the $^8$B solar neutrino flux in SNO+ with very low backgrounds AGOSTINI 2018B NAT 562 505 Comprehensive measurement of $pp$-chain solar neutrinos ABE 2016C PR D94 052010 Solar Neutrino Measurements in Super-Kamiokande-IV ABE 2011B PR C84 035804 Measurement of the ${}^{8}\mathrm {B}$ Solar Neutrino Flux with the KamLAND Liquid Scintillator Detector ABE 2011 PR D83 052010 Solar Neutrino Results in Super-Kamiokande-III BELLINI 2010A PR D82 033006 Measurement of the Solar ${}^{8}\mathrm {B}$ Neutrino Rate with a Liquid Scintillator Target and 3 MeV Energy Threshold in the Borexino Detector AHARMIM 2008 PRL 101 111301 Independent Measurement of the Total Active ${}^{8}\mathrm {B}$ Solar Neutrino Flux Using an Array of ${}^{3}\mathrm {He}$ Proportional Counters at the Sudbury Neutrino Observatory Also PR C87 015502 Measurement of the ${{\mathit \nu}_{{e}}}$ and Total ${}^{8}\mathrm {B}$ Solar Neutrino Fluxes with the Sudbury Neutrino Observatory Phase-III Data Set CRAVENS 2008 PR D78 032002 Solar Neutrino Measurements in Super-Kamiokande-II HOSAKA 2006 PR D73 112001 Solar Neutrino Measurements in Super-Kamiokande-I AHARMIM 2005A PR C72 055502 Search for Periodicities in the ${}^{8}\mathrm {B}$ Solar Neutrino Flux Measured by the Sudbury Neutrino Observatory AHMAD 2002 PRL 89 011301 Direct Evidence for Neutrino Flavor Transformation from Neutral Current Interactions in the Sudbury Neutrino Observatory AHMAD 2001 PRL 87 071301 Measurement of Charged Current Interactions Produced by ${}^{8}\mathrm {B}$ Solar Neutrinos at the SUDBURY Neutrino Observatory FUKUDA 1996 PRL 77 1683 Solar Neutrino Data Covering Solar Cycle 22