NuRadioReco.modules.io.coreas.readCoREASDetector module

NuRadioReco.modules.io.coreas.readCoREASDetector.get_random_core_positions(xmin, xmax, ymin, ymax, n_cores, seed=None)

Generate random core positions within a rectangle

Parameters:

xmin: float

minimum x value

xmax: float

maximum x value

ymin: float

minimum y value

ymax: float

maximum y value

n_cores: int

number of cores to generate

seed: int

seed for the random number generator

Returns:

cores: np.ndarray

array containing the core positions, shaped as (n_cores, 2)

NuRadioReco.modules.io.coreas.readCoREASDetector.apply_hanning(efield)

Apply a half-Hann window to the electric field in the time domain. This smoothens the edges to avoid ringing effects.

Parameters:

efield: np.ndarray

The electric field in the time domain, shaped as (n_samples, n_polarizations)

Returns:

smoothed_efield: np.ndarray

The smoothed trace, shaped as (n_samples, n_polarizations)

NuRadioReco.modules.io.coreas.readCoREASDetector.select_channels_per_station(det, station_id, requested_channel_ids)

Returns a defaultdict object containing the requested channel ids that are in the given station. This dict contains the channel group ids as keys with lists of channel ids as values.

Parameters:

detDetectorBase

The detector object that contains the station

station_idint

The station id to select channels from

requested_channel_idslist of int

List of requested channel ids

Returns:

channel_idsdefaultdict

Dictionary with channel group ids as keys and lists of channel ids as values

class NuRadioReco.modules.io.coreas.readCoREASDetector.readCoREASDetector

Bases: object

Use this as default when reading CoREAS files and combining them with a detector.

This module reads the electric fields of a CoREAS file with a star shaped pattern of observers. The electric field is then interpolated at the positions of the antennas or stations of a detector. If the angle between magnetic field and shower direction are below about 15 deg, the interpolation is no longer reliable and the closest observer is used instead.

Methods

begin(input_file[, interp_lowfreq, ...])	Begin method to initialize readCoREASDetector module.
run(detector, core_position_list[, ...])	run method, get interpolated electric fields for the given detector and core positions and set them in the event.

end

begin(input_file, interp_lowfreq=0.03, interp_highfreq=1.0, site=None, declination=None, log_level=0)

Begin method to initialize readCoREASDetector module.

This function creates an Event using the provided CoREAS HDF5 file, using the coreas.read_CORSIKA7() function. The latter takes in the declination and site parameters in order to specify the declination of the magnetic field. Then, it creates a coreasInterpolator.coreasInterpolator() object with the event and initializes the electric field interpolator.

Parameters:

input_file: str

coreas hdf5 file

interp_lowfreq: float, default=30 * units.MHz

lower frequency for the bandpass filter in interpolation, should be broader than the sensitivity band of the detector

interp_highfreq: float, default=1000 * units.MHz

higher frequency for the bandpass filter in interpolation, should be broader than the sensitivity band of the detector

declination: float, default=None

The declination to use for the magnetic field, in internal units. Takes precedence over site. This parameter is passed on to the coreas.read_CORSIKA7() function.

site: str, default=None

Instead of declination, a site name can be given to retrieve the declination. This parameter is passed on to the coreas.read_CORSIKA7() function.

log_level: default=logging.NOTSET

log level for the logger

run(detector, core_position_list, selected_station_channel_ids=None)

run method, get interpolated electric fields for the given detector and core positions and set them in the event. The trace is smoothed with a half-Hann window to avoid ringing effects. When using short traces, this might have a significant effect on the result.

Parameters:

detector: `NuRadioReco.detector.detector_base.DetectorBase`

Detector description of the detector that shall be simulated

core_position_list: list of (list of float)

List of 2D or 3D core positions in the format [[x1, y1, (z1)], [x2, y2, (z2)], …] The z coordinate is optional. It is actually encouraged to not use it, as it can mess with the observation level of the event. If not provided, all oberser positions are put at the observation by the interpolator (this is the behaviour of coreasInterpolator.get_interp_efield_value).

selected_station_channel_ids: dict, default=None

A dictionary containing the list of channels IDs to simulate per station. If None, all channels of all stations in the detector are simulated. To select a station and simulate all its channels, set its value to None.

Yields:

evtNuRadioReco.framework.event.Event

An Event containing a Station object for every selected station, which holds a SimStation containing the interpolated ElectricField traces for the selected channels.

Examples

When running the module, you will probably want to run it with 2-dimensional core positions. This ensures that the observation level is not altered. It is possible to run with 3-dimensional core positions, but be careful to have the correct altitude, otherwise unexpected results might occur.

>>> reader = readCoREASDetector()
>>> reader.begin('coreas.hdf5', interp_lowfreq=30 * units.MHz, interp_highfreq=80 * units.MHz)
>>> for evt in reader.run(detector, [[0, 0], [10 * units.m, 10 * units.m]]):
>>>     print(evt.get_id())

If we only want to simulate a subset of the stations of our detector, we can select them by passing a dictionary for the selected_station_channel_ids parameter. The keys should be the station IDs and the value should be None to indicate we want to simulate all channels. So to simulate all channels of stations 2 and 7, we would do the following.

>>> my_selection = {2: None, 7: None}
>>> reader = readCoREASDetector()
>>> reader.begin('coreas.hdf5', interp_lowfreq=30 * units.MHz, interp_highfreq=80 * units.MHz)
>>> for evt in reader.run(detector, [[0, 0], [10 * units.m, 10 * units.m]], selected_station_channel_ids):
>>>     print(evt.get_id())

Setting the value to a list of channel IDs will only simulate these selected channels of the station they are associated to. Here we simulate the first 4 channels of station 2 and the first 2 channels of station 7, for the case of the LOFAR detector description.

>>> my_selection = {2: [2000000, 2000001, 2000002, 2000003], 7: [7000000, 7000001]}
>>> reader = readCoREASDetector()
>>> reader.begin('coreas.hdf5', interp_lowfreq=30 * units.MHz, interp_highfreq=80 * units.MHz)
>>> for evt in reader.run(detector, [[0, 0], [10 * units.m, 10 * units.m]], selected_station_channel_ids):
>>>     print(evt.get_id())

end()