Sequence description parameters

Field	Value type	Req?	Description	Example value
sequenceName	Str	Y	Sequence name	svs_slaser
description	Str	Y	User description	3T slaser 28 ms
B0	float	Y	Static field strength	6.98
centralShift	float	N	Receiver offset from ppm reference. For most 1H MRS sequences this will be 4.65 ppm (the shift of water at 37 °C from TMS/DSS). Default = 0.0	4.65
RX_Points	int	Y	Number of points in the final spectrum	4096
RX_SW	float	Y	Receiver sweep-width (bandwidth) in Hz	6000
RX_LW	float	Y	FWHM of peaks in the output spectra. In Hz.	2.0
RX_Phase	float	Y	Zero-order phase applied to final spectra. In radians.	0.0
x	float (1x2)	Y	Spatial range simulated in x direction. In units specified by spaceUnits.	[-25 25]
y	float (1x2)	Y	As above for y	[-25 25]
z	float (1x2)	Y	As above for z	[-25 25]
resolution	Int (1x3)	Y	Number of spatial points to simulate in each dimension.	[25 25 1]
CoherenceFilter	Int (1x Nblocks)	Y	Coherence order NOT zeroed at end of block. Value of element can be ‘None’ for no coherence selection. See below for more information.	[1 0 -1]
RFUnits	Str	N	Units of RF amplitude (options: ’Hz’ ’T’ ’mT’ ’uT’; default=’Hz’)	‘Hz’
GradUnits	Str	N	Units of gradient amplitude per meter (options: ’Hz’ ’T’ ’mT’; default=’T’)	‘mT’
spaceUnits	Str	N	Units of spatial position (options: ’mm’ ’cm’ ’m’; default=’m’)	‘mm’
RF	List of NBlocks	Y	Sequence block description. Contains the fields listed below.	[block1 … blockN]

Sequence block parameters

Parameters required for the nested sequence blocks of the RF array in the above table. These parameters describe one block of the sequence RF (with or without gradient), rephasing, delay.

Field	Value type	Req?	Description	Example value
time	float	Y	Total pulse time. In seconds.	0.003
frequencyOffset	float	N	Offset of pulse central frequency from receiver centre. In Hz.	-246
phaseOffset	float	N	Phase offset applied to whole pulse. In radians. Default = 0.	0.0
amp	List of floats	Y	List of amplitudes in units specified by RFUnits. Must contain >=1 points.	[0 1.0 … 1.0 0.0]
phase	List of floats	Y	List of pulse phase points. Must match the size of amp. In radians.	[0 0.0 … 0.0 0.0]
grad	Float (1x3)	Y	Slice selection gradient amplitude (in GradUnits/m) for each of the three spatial axes.	[3.5 0 0]
ampScale	Float	N	Optional scaling of the pulse amplitude. Default = 1.0.	2.0
delays	Float (1x Nblocks)	Y	Free evolution time after RF in each RF block. In seconds. Measured from end of RF to start of next RF.	[0.005 0.001 0.005]
rephaseAreas	Float (Nblocksx3)	Y	Area of gradients (in seconds.GradUnits/m) on each spatial axis during the delay time. Can be applied on more than one axis per block.	[[-5.1e-3 0 0] [ 0 -5.1e-3 0] [ 0 0 -5.1e-3]]