hardRFΒΆ

The most common used rectangle or hard pulses are realized by hardRF block.

Turn to shapedRF for shaped pulses.

The syntax to create a rectangle pulse is quite simple:

local rf = hardRF{}

The parameter structure is summarized as follow:

Parameter Mandatory/Optional Content
beta M Flip angle in degree.
channel O Nuclear isotope(s) for this pulse, default is "1H". For other nuclei, explicit nuclear isotope such as channel = "13C" or channel = "1H|13C" is required. Note for more channels, you only need to seperate the parameter for each channel with |.
phase O Phase for this pulse, default is "x" phase. Shortcut symbols include "x", "-x", "y", "-y". You can also directly assign a numerical phase in degree such as "30" for customized phase. Similar to the channel, you only need to seperate the phase for each channel with |.
width O Pulse duration in ms. If assigned, the amplitude will be determined automatically by the flip angle beta.

Note

Pulse duration is proportional to that of the standard 90 degree pulse (default 5 microsecond), which indicates that the pulse amplitude is fixed for different flip angles.

The duration of standard 90 degree pulse can be globally declared as follow:

pw90{10} -- unit in microsecond.

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--[[ Copyright 2019 The Spin-Scenario Authors. All Rights Reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
==============================================================================-]]

-- example: Hard RF pulse. 

-- 60 degree -y-pulse for proton 1H excitation.
local rf1 = hardRF{beta =60, phase="-y"}
write("rf1.RF",rf1)

-- a refocusing pulse applied on a heteronuclear 1H-13C spin system
local rf2 = hardRF{beta =180, channel ="1H|13C", phase="x|x"}
write("rf2.RF",rf2)