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Table 5 Values of Aa index corresponding to Fig. 4

From: New perspectives on contributing factors to the monthly behavior of the aa geomagnetic index

Cycles

Mean 1–27

σ

aa Min

#σ

New Moon

#σ

Mean 29–40

#σ

ALL

14.70

0.27

13.51

4.41

14.43

1.00

14.73

0.25

ALL A

8.81

0.24

8.05

3.17

8.47

1.42

8.87

0.18

ALL D

9.14

0.22

8.38

3.50

9.04

0.50

9.11

0.19

T1

7.66

0.19

7.02

3.37

7.35

1.63

7.69

0.12

T1 A

4.33

0.14

3.97

2.57

4.07

1.86

34.41

0.10

T1 D

14.11

0.11

3.61

4.55

4.04

0.64

4.08

0.08

T2

7.88

0.23

7.25

2.74

7.82

0.26

7.76

0.21

T2 A

4.50

0.18

3.97

2.94

4.40

0.56

4.42

0.17

T2 D

23.81

0.12

3.54

2.25

3.8

*0.17

43.76

0.09

  1. σ = one standard deviation; #σ = number of standard deviations. In the #σ columns, the sign * before a number means the number of σ’s above the mean value of aa. No sign before a number means the number of σ’s below the mean value of aa. 1Average during days 1–26. 2Average during days 1–24. 3Average during days 28–40. 4Average during days 26–40
  2. First column: type of cycle. Second and third columns: means of the time intervals between day 1 to one day before the Aa minimum and their standard deviations, respectively. Fourth and fifth columns: Aa minima day value and the number of standard deviations of these values with respect to the mean (according to the third column). Sixth and seventh columns: Aa value at new Moon and the number of standard deviations of these values with respect to the mean (according to the third column). Eighth and ninth columns: Aa mean value for days 29–40 and their corresponding standard deviations, respectively. This time span included the full Moon