diff --git a/doc/changelog.rst b/doc/changelog.rst
index 61c7944046512321cb8c2c3b89d4d93f3e6b187a..d9da9472a824e1d2c3cc6fd8f405900f2d6f121f 100644
--- a/doc/changelog.rst
+++ b/doc/changelog.rst
@@ -24,6 +24,7 @@ unreleased
     - streamline digitizer functions :mr:`304`
     - add BAM average and BAM feedbacks mnemonics, Viking mnemonics :mr:`305`, :mr:`306`
     - improved function to load PES spectra :mr:`309`
+    - Gotthard-II mnemonics and pulse alignment :mr:`310`
 
 - **New Features**
 
diff --git a/src/toolbox_scs/constants.py b/src/toolbox_scs/constants.py
index 51f8715e0ad9509ff6391108708c9d8f28674c85..ba0945c5cfe239c109fb5cc6ec187a9a6264615a 100644
--- a/src/toolbox_scs/constants.py
+++ b/src/toolbox_scs/constants.py
@@ -1101,16 +1101,22 @@ mnemonics = {
     "Gotthard2": ({'source': 'SCS_PAM_XOX/DET/GOTTHARD_RECEIVER2:daqOutput',
                    'key': 'data.adc',
                    'dim': ['gott_pId', 'pixelId']},),
-    "GH21": ({'source': 'SCS_XOX_GH21/CORR/GOTTHARD2_RECEIVER1:daqOutput',
+    "GH21": ({'source': 'SCS_XOX_GH21/CORR/RECEIVER:daqOutput',
+              'key': 'data.adc',
+              'dim': ['gh2_pId', 'pixelId']},
+             {'source': 'SCS_XOX_GH21/CORR/GOTTHARD2_RECEIVER1:daqOutput',
               'key': 'data.adc',
               'dim': ['gh2_pId', 'pixelId']},),
-    "GH22": ({'source': 'SCS_XOX_GH22/CORR/GOTTHARD2_RECEIVER1:daqOutput',
+    "GH22": ({'source': 'SCS_XOX_GH22/CORR/RECEIVER:daqOutput',
+              'key': 'data.adc',
+              'dim': ['gh2_pId', 'pixelId']},
+             {'source': 'SCS_XOX_GH22/CORR/GOTTHARD2_RECEIVER2:daqOutput',
               'key': 'data.adc',
               'dim': ['gh2_pId', 'pixelId']},),
     "GH21_raw": ({'source': 'SCS_XOX_GH21/DET/GOTTHARD2_RECEIVER1:daqOutput',
                   'key': 'data.adc',
                   'dim': ['gh2_pId', 'pixelId']},),
-    "GH22_raw": ({'source': 'SCS_XOX_GH22/DET/GOTTHARD2_RECEIVER1:daqOutput',
+    "GH22_raw": ({'source': 'SCS_XOX_GH22/DET/GOTTHARD2_RECEIVER2:daqOutput',
                   'key': 'data.adc',
                   'dim': ['gh2_pId', 'pixelId']},),
 
diff --git a/src/toolbox_scs/detectors/__init__.py b/src/toolbox_scs/detectors/__init__.py
index 2b7be5e84f83169782bceafc4cc47bffbcfd6cfc..3f442878f734a9c4ad8568e15a6b187c31043a61 100644
--- a/src/toolbox_scs/detectors/__init__.py
+++ b/src/toolbox_scs/detectors/__init__.py
@@ -5,6 +5,7 @@ from .dssc import *
 from .dssc_data import *
 from .dssc_misc import *
 from .dssc_processing import *
+from .gotthard2 import *
 from .hrixs import *
 from .pes import *
 from .viking import *
@@ -18,6 +19,7 @@ __all__ = (
     + dssc_data.__all__
     + dssc_misc.__all__
     + dssc_processing.__all__
+    + gotthard2.__all__
     + hrixs.__all__
     + pes.__all__
     + viking.__all__
diff --git a/src/toolbox_scs/detectors/gotthard2.py b/src/toolbox_scs/detectors/gotthard2.py
new file mode 100644
index 0000000000000000000000000000000000000000..bf2988cafbcaf050b7e17f98cbf8fe99d16a5545
--- /dev/null
+++ b/src/toolbox_scs/detectors/gotthard2.py
@@ -0,0 +1,75 @@
+""" Gotthard-II detector related sub-routines
+
+    Copyright (2024) SCS Team.
+
+    (contributions preferrably comply with pep8 code structure
+    guidelines.)
+"""
+from extra.components import OpticalLaserPulses, XrayPulses
+import numpy as np
+import xarray as xr
+import logging
+__all__ = [
+    'extract_GH2',
+]
+
+log = logging.getLogger(__name__)
+
+
+def extract_GH2(ds, run, firstFrame=0, bunchPattern='scs_ppl',
+                gh2_dim='gh2_pId'):
+    '''
+    Select and align the frames of the Gotthard-II that have been exposed
+    to light.
+
+    Parameters
+    ------
+    ds: xarray.Dataset
+        The dataset containing GH2 data
+    run: extra_data.DataCollection
+        The run containing the bunch pattern source
+    firstFrame: int
+        The GH2 frame number corresponding to the first pulse of the train.
+    bunchPattern: str in ['scs_ppl', 'sase3']
+        the bunch pattern used to align data. For 'scs_ppl', the gh2_pId
+        dimension in renamed 'ol_pId', and for 'sase3' gh2_pId is renamed
+        'sa3_pId'.
+    gh2_dim: str
+        The name of the dimension that corresponds to the Gotthard-II frames.
+
+    Returns
+    -------
+    nds: xarray Dataset
+        The aligned and reduced dataset with only-data-containing GH2
+        variables.
+    '''
+    if gh2_dim not in ds.dims:
+        log.warning(f'gh2_dim "{gh2_dim}" not in dataset. Skipping.')
+        return ds
+    if bunchPattern == 'scs_ppl':
+        pattern = OpticalLaserPulses(run)
+        dim = 'ol_pId'
+    else:
+        pattern = XrayPulses(run)
+        dim = 'sa3_pId'
+    others = [var for var in ds if dim in ds[var].coords]
+    nds = ds.drop_dims(dim)
+    if pattern.is_constant_pattern():
+        pulse_ids = pattern.peek_pulse_ids(labelled=False)
+        nds = nds.isel({gh2_dim: pulse_ids + firstFrame})
+        nds = nds.assign_coords({gh2_dim: pulse_ids})
+        nds = nds.rename({gh2_dim: dim})
+    else:
+        log.warning('The number of pulses has changed during the run.')
+        pulse_ids = np.unique(pattern.pulse_ids(labelled=False, copy=False))
+        nds = nds.isel({gh2_dim: pulse_ids + firstFrame})
+        nds = nds.assign_coords({gh2_dim: pulse_ids})
+        nds = nds.rename({gh2_dim: dim})
+        mask = pattern.pulse_mask(labelled=False)
+        mask = xr.DataArray(mask, dims=['trainId', dim],
+                            coords={'trainId': run.train_ids,
+                                    dim: np.arange(mask.shape[1])})
+        mask = mask.sel({dim: pulse_ids})
+        nds = nds.where(mask, drop=True)
+    ret = ds[others].merge(nds, join='inner')
+    return ret