IAPS - Wind velocity-magnetic field correlation coefficient data of solar wind streams

The velocity - magnetic field (v-b) correlation coefficient unables to identify Alfvénic solar wind intervals (along with almost constant magnetic field magnitude and proton number density). It is derived as the ratio between the covariance of velocity and magnetic field (in Alfvén units) components and the product of their standard deviations, in a time window ranging between tens of minutes to hours. In principle, this formula should be applied to every component of the velocity (V_i) and magnetic fields (B_i) (with i = R, T, N in RTN coordinate system or i = X, Y, Z in GSE coordinate system). The total correlation coefficient is then derived as the average from the three components. However, for the sake of simplicity, we consider only the N component since more Alfvénic than the other two.

References

D’Amicis et al, GRL, 34, L05108, 2007; Frontiers in Physics, 8, 541, 2020

Telloni et al, ApJ, 916, 64, 2021

D’Amicis et al, A&A, 656, A21, 2021

Tu et al., JGR, 94, 11739, 1989

Dataset summary

internal_name:	inaf_vbcorr_wind_tableset
publisher:	INAF-IAPS, Fisica dei Plasmi Spaziali e Space Weather
alph_code:	24C
id_tmp:	98
short_name:	wind_v-b_corr
identifier:	aspis://inaf/vbcorr_wind_tableset
dynamic:	static
size:	35MB
format:	csv
type:	tableset
records_number:	538
time_start:	1998-10-01
time_stop:	2022-05-06
spatial:	L1
messenger:	protons
spectral_min:	0
spectral_max:	0
spectral_units:
observable:	{SW}
latest update:	2024-04-04 02:05:02

Columns specification

progr	column	units	type	description
1	time	UTC	datetime	2017-03-25T00:00:06 [UTC] - the UTC time associated to the masure
2	vb_coeff_corr	number	float	-0.98 [dimensionless] the Pearson’s correlation coefficient between the normal components of velocity and magnetic field
3	sample	number	int	75 [samples] the number of observations available in the 30-min window
4	scale	min	int	30 [minutes] the length of the window, i.e. 30 min