BiSON Frequencies

The Birmingham Solar Oscillations Network (BiSON) provides high-quality high-cadence observations from as far back in time as 1978. Here we present the frequencies for the Sun-as-a-star global modes of oscillation.

2014 - Low-frequency, low-degree solar p-mode properties.

Please cite 10.1007/s11207-015-0810-0 and 10.1093/mnras/stu080 when publishing any results produced from these data.

The solar low-degree low-frequency modes of oscillation are of particular interest as their frequencies can be measured with very high precision and hence provide good constraints on seismic models. Here we detect and characterize these valuable measures of the solar interior from a 22 yr Birmingham Solar Oscillations Network data set. We report mode frequencies, line widths, heights, amplitudes, and rotational splitting, all with robust uncertainties. The new values of frequency, rotational splitting, amplitude, and line width we provide will help place new constraints on hydrostatic and rotational structure, plus diagnostics of near-surface convection. Further to this, by assuming simple power laws, we extrapolate mode properties to lower frequencies. We demonstrate that the low-l low-frequency p modes have a low signal-to-noise ratio and that this cannot be overcome simply by continued observation. It will be necessary to observe the Sun in novel ways to `beat' the intrinsic granulation noise.


         n  l     Freq   Error
         6  0   972.615  0.002 
         7  0  1117.993  0.004 
         7  1  1185.604  0.003 
         8  0  1263.198  0.005 
         8  1  1329.635  0.003 
         8  2  1394.689  0.005 
         9  0  1407.472  0.006 
         9  1  1472.839  0.006 
         9  2  1535.853  0.005
        10  0  1548.336  0.007
         9  3  1591.536  0.014 
        10  1  1612.724  0.006
        10  2  1674.538  0.008 
        11  0  1686.594  0.012 
        10  3  1729.088  0.022 
        11  1  1749.285  0.007 
        11  2  1810.308  0.009 
        12  0  1822.202  0.012 
        11  3  1865.280  0.016 
        12  1  1885.089  0.009 
        12  2  1945.824  0.013 
        13  0  1957.452  0.012 
  

2009 - Definitive Sun-as-a-star p-mode frequencies.

Please cite 10.1007/s11207-015-0810-0 and 10.1111/j.1745-3933.2009.00672.x when publishing any results produced from these data.

We present a list of `best possible estimates' of low-degree p-mode frequencies from 8640 days of observations made by the Birmingham Solar-Oscillations Network (BiSON). This is the longest stretch of helioseismic data ever used for this purpose, giving exquisite precision in the estimated frequencies. Every effort has been made in the analysis to ensure that the frequency estimates are also accurate. In addition to presenting the raw best-fitting frequencies from our `peak-bagging' analysis, we also provide tables of corrected frequencies pertinent to the quiet-Sun and an intermediate level of solar activity.

These are corrected frequencies pertinent to the quiet Sun.


         n  l     Freq   Error
         6  0   972.613  0.002
         7  1  1185.592  0.004
         8  0  1263.162  0.012 
         8  1  1329.629  0.004 
         8  2  1394.680  0.011
         9  0  1407.481  0.012 
         9  1  1472.835  0.007 
         9  2  1535.859  0.011
        10  0  1548.333  0.007 
        10  1  1612.720  0.007 
        10  2  1674.534  0.008 
        10  3  1729.085  0.016
        11  0  1686.597  0.011 
        11  1  1749.279  0.007 
        11  2  1810.304  0.009 
        11  3  1865.293  0.019
        12  0  1822.196  0.011 
        12  1  1885.081  0.009 
        12  2  1945.797  0.013 
        12  3  2001.243  0.017
        13  0  1957.421  0.012 
        13  1  2020.793  0.010 
        13  2  2082.102  0.015 
        13  3  2137.788  0.019
        14  0  2093.518  0.013 
        14  1  2156.784  0.014 
        14  2  2217.656  0.018 
        14  3  2273.516  0.026
        15  0  2228.749  0.014 
        15  1  2291.993  0.015 
        15  2  2352.222  0.017
        15  3  2407.643  0.025
        16  0  2362.788  0.016 
        16  1  2425.595  0.015 
        16  2  2485.873  0.019 
        16  3  2541.671  0.023
        17  0  2496.180  0.017 
        17  1  2559.162  0.015 
        17  2  2619.668  0.018 
        17  3  2676.149  0.023
        18  0  2629.668  0.015 
        18  1  2693.347  0.014 
        18  2  2754.439  0.017 
        18  3  2811.318  0.021
        19  0  2764.142  0.015 
        19  1  2828.150  0.014 
        19  2  2889.578  0.018 
        19  3  2946.935  0.021
        20  0  2899.022  0.013 
        20  1  2963.322  0.014 
        20  2  3024.689  0.018 
        20  3  3082.273  0.025
        21  0  3033.754  0.014 
        21  1  3098.140  0.015 
        21  2  3159.821  0.020 
        21  3  3217.683  0.028
        22  0  3168.618  0.017 
        22  1  3233.139  0.018 
        22  2  3295.063  0.025 
        22  3  3353.335  0.041
        23  0  3303.520  0.021 
        23  1  3368.469  0.023 
        23  2  3430.748  0.034 
        23  3  3489.409  0.053
        24  0  3438.992  0.030 
        24  1  3504.129  0.030 
        24  2  3566.949  0.044 
        24  3  3626.078  0.075
        25  0  3574.893  0.048 
        25  1  3640.475  0.038 
        25  2  3703.044  0.067 
        25  3  3762.530  0.105
        26  0  3710.717  0.088 
        26  1  3777.067  0.052 
        26  2  3839.717  0.144
        27  0  3846.993  0.177 
        27  1  3913.570  0.068 
        27  2  3976.930  0.298
        28  0  3984.214  0.323