| barn | 1 b | 2 b | 3 b | 4 b | 5 b | 6 b | 7 b | 8 b | 9 b | 10 b | 11 b | 12 b | 13 b | 14 b | 15 b | 16 b | 17 b | 18 b | 19 b | 20 b | 21 b | 22 b | 23 b | 24 b | 25 b | 26 b | 27 b | 28 b | 29 b | 30 b | 31 b | 32 b | 33 b | 34 b | 35 b | 36 b | 37 b | 38 b | 39 b | 40 b | 41 b | 42 b | 43 b | 44 b | 45 b | 46 b | 47 b | 48 b | 49 b | 50 b | 51 b | 52 b | 53 b | 54 b | 55 b | 56 b | 57 b | 58 b | 59 b | 60 b | 61 b | 62 b | 63 b | 64 b | 65 b | 66 b | 67 b | 68 b | 69 b | 70 b | 71 b | 72 b | 73 b | 74 b | 75 b | 76 b | 77 b | 78 b | 79 b | 80 b | 81 b | 82 b | 83 b | 84 b | 85 b | 86 b | 87 b | 88 b | 89 b | 90 b | 91 b | 92 b | 93 b | 94 b | 95 b | 96 b | 97 b | 98 b | 99 b | 100 b |
| square picometer | 0.0001 pm2 | 0.0002 pm2 | 0.0003 pm2 | 0.0004 pm2 | 0.0005 pm2 | 0.0006 pm2 | 0.0007 pm2 | 0.0008 pm2 | 0.0009 pm2 | 0.001 pm2 | 0.0011 pm2 | 0.0012 pm2 | 0.0013 pm2 | 0.0014 pm2 | 0.0015 pm2 | 0.0016 pm2 | 0.0017 pm2 | 0.0018 pm2 | 0.0019 pm2 | 0.002 pm2 | 0.0021 pm2 | 0.0022 pm2 | 0.0023 pm2 | 0.0024 pm2 | 0.0025 pm2 | 0.0026 pm2 | 0.0027 pm2 | 0.0028 pm2 | 0.0029 pm2 | 0.003 pm2 | 0.0031 pm2 | 0.0032 pm2 | 0.0033 pm2 | 0.0034 pm2 | 0.0035 pm2 | 0.0036 pm2 | 0.0037 pm2 | 0.0038 pm2 | 0.0039 pm2 | 0.004 pm2 | 0.0041 pm2 | 0.0042 pm2 | 0.0043 pm2 | 0.0044 pm2 | 0.0045 pm2 | 0.0046 pm2 | 0.0047 pm2 | 0.0048 pm2 | 0.0049 pm2 | 0.005 pm2 | 0.0051 pm2 | 0.0052 pm2 | 0.0053 pm2 | 0.0054 pm2 | 0.0055 pm2 | 0.0056 pm2 | 0.0057 pm2 | 0.0058 pm2 | 0.0059 pm2 | 0.006 pm2 | 0.0061 pm2 | 0.0062 pm2 | 0.0063 pm2 | 0.0064 pm2 | 0.0065 pm2 | 0.0066 pm2 | 0.0067 pm2 | 0.0068 pm2 | 0.0069 pm2 | 0.007 pm2 | 0.0071 pm2 | 0.0072 pm2 | 0.0073 pm2 | 0.0074 pm2 | 0.0075 pm2 | 0.0076 pm2 | 0.0077 pm2 | 0.0078 pm2 | 0.0079 pm2 | 0.008 pm2 | 0.0081 pm2 | 0.0082 pm2 | 0.0083 pm2 | 0.0084 pm2 | 0.0085 pm2 | 0.0086 pm2 | 0.0087 pm2 | 0.0088 pm2 | 0.0089 pm2 | 0.009 pm2 | 0.0091 pm2 | 0.0092 pm2 | 0.0093 pm2 | 0.0094 pm2 | 0.0095 pm2 | 0.0096 pm2 | 0.0097 pm2 | 0.0098 pm2 | 0.0099 pm2 | 0.01 pm2 |
A barn (symbol: b) is a unit of area equal to 10−28 m2 (100 fm2). Originally used in nuclear physics for expressing the cross sectional area of nuclei and nuclear reactions, today it is also used in all fields of high-energy physics to express the cross sections of any scattering process, and is best understood as a measure of the probability of interaction between small particles.
| Name of unit | Symbol | Definition | Relation to SI units | Unit System |
|---|---|---|---|---|
| barn | b | ≡ 10−28 m2 | ≡ 10−28 m2 | Nuclear Physics |
| barns | square picometers | barns | square picometers |
|---|---|---|---|
| 1 | = 0.0001 | 6 | = 0.0006 |
| 2 | = 0.0002 | 7 | = 0.0007 |
| 3 | = 0.0003 | 8 | = 0.0008 |
| 4 | = 0.0004 | 9 | = 0.0009 |
| 5 | = 0.0005 | 10 | = 0.001 |
Square picometre or Square picometer is a SI prefixes applied unit of area, symbol pm2, is a multiple of the of SI prefixes (pico) used with the metre.
| Name of unit | Symbol | Definition | Relation to SI units | Unit System |
|---|---|---|---|---|
| square picometer | pm2 | ≡ 1 pm × 1 pm ≡ 10-12 m × 10-12 m | = 10-24 m2 | Metric system SI |
| square picometers | barns | square picometers | barns |
|---|---|---|---|
| 1 | = 10000 | 6 | = 60000 |
| 2 | = 20000 | 7 | = 70000 |
| 3 | = 30000 | 8 | = 80000 |
| 4 | = 40000 | 9 | = 90000 |
| 5 | = 50000 | 10 | = 100000 |
| barns | square picometers |
|---|---|
| 1 | = 0.0001 |
| 10 000 | = 1 |
| Symbol | Definition |
|---|---|
| ≡ | exactly equal |
| ≈ | approximately equal to |
| = | equal to |
| digits | indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …) |