Issue with the initial magnetic field in 1d magnetic reconnection

[deSUBHAM]

Hi,

I am testing one 1d asymmetric magnetic reconnection with pec boundary condition. Please refer to the attached input file. To my surprise, I could not even initialise the magnetic field as expected, while the number density matches perfectly. Please see the attached figure. The solid line is from simulation, while the dashed line is the corresponding equation (i.e. expected ones). For the magnetic field, it initialise with the lower value of it, while I clearly initialise it with a 'tanh' shear. I checked with increasing resolution and particle per cell. I also changed the boundary condition to Silver-Muller. Nevertheless, I failed to initialised the magnetic file as I expected. I would appreciate if anyone can help me here find the mistake I made here.

Thank you so much.

input_1d_pec.txt

[RemiLehe]

Thanks for raising this question @deSUBHAM

I just tried to run your input script, and I do see a non-zero Bx field at t=0:

But it seems that its amplitude (~100e-9 T) is much lower than what you were expecting (~1.5 from your plot above, assuming the unit is Teslas).

Could you maybe check the formulas in your input script, esp:

my_constants.B0 = sqrt((alp/R)*((tau+1.0)/tau)*n0*mu0*theta_i*mass_ion*clight*clight)   #Amp of mag field

Making sure that this is compatible with the fact that the B field is expressed in Teslas in WarpX.