48 shot spiral images are as follows:

 

The gradient waveform is as follows:

The pulse sequence is as follows:

from psdk import *
import numpy as np

gamma = 42.57747892 # [MHz/T]
TR = 40000.0e+3 # [us]
TE = 4.0e+3 # [us]
NR = 1495 # Number of readout points
NSHOT = 48 # Number of shots
fov = [256.0, 256.0, 256.0] # [mm]
dwell_time = 5.0 # [us]
slice_width = 6.0 # [mm]
# gx_value = 1e+6 / (dwell_time * gamma * fov[0]) # [mT/m]
# gy_value = 2e+6 / (dwell_time * gamma * fov[1]) * NPE1 / NR # [mT/m]
gz_value = 1.25 / (slice_width * 1.0e-3) / gamma # [mT/m]
gx_rise_time = 300.0 # [us]
gy_rise_time = 300.0 # [us]
gz_rise_time = 300.0 # [us]
excitation_pulse_width = 1600.0 # [us]
excitation_pulse_flip_angle = 90.0 # [degree]
gx_waveform = np.fromfile('GX.dbl', dtype=np.float64)
gy_waveform = np.fromfile('GY.dbl', dtype=np.float64)

def sinc_with_hamming(flip_angle, pulse_width, points, *, min=-2.0*np.pi, max=2.0*np.pi):
    x0 = np.arange(min, max, (max - min) / points)
    x1 = x0 + (max - min) / points
    y = (np.sinc(x0 / np.pi) + np.sinc(x1 / np.pi)) * 0.5 * np.hamming(points)
    return flip_angle * y * points / (y.sum() * pulse_width * 360.0e-6 * gamma)

with Sequence('2D Spiral'):

    with Block('Excitation', excitation_pulse_width + 2.0*gz_rise_time):
        GZ(0.0, gz_value, gz_rise_time)
        RF(gz_rise_time, sinc_with_hamming(excitation_pulse_flip_angle, excitation_pulse_width, 160), excitation_pulse_width / 160)
        GZ(excitation_pulse_width + gz_rise_time, 0.0, gz_rise_time)

    with Block("Slice_refocus", excitation_pulse_width * 0.5 + gz_rise_time * 2.0) :
        GZ(0.0, -gz_value, gz_rise_time)
        GZ(excitation_pulse_width * 0.5 + gz_rise_time, 0.0, gz_rise_time) 
        
    with Block('Readout', 10240):
        GX.waveform(0.0, ([gx_waveform[i * 2048:(i+1)*2048:] for i in range(NSHOT)], ['SHOT']), 5.0)
        GY.waveform(0.0, ([gy_waveform[i * 2048:(i+1)*2048:] for i in range(NSHOT)], ['SHOT']), 5.0)
        AD(0.0, NR, dwell_time)
                
    with Main():
        with Loop('SHOT', NSHOT):
            BlockRef('Excitation')
            BlockRef('Slice_refocus')
            WaitUntil(TE)
            BlockRef('Readout')
            WaitUntil(TR)