Telescope

class showermodel.telescope.Telescope(x=0.0, y=0.0, z=0.0, theta=0.0, alt=None, az=0.0, tel_type=None, efficiency=None, apert=None, area=None, N_pix=None, int_time=None)

Bases: object

Object containing the characteristics of a Cherenkov/fluorescence telescope.

Parameters

tel_type (str) – Name given to the telescope. Default to None.
x (float) – East coordinate of the telescope in km.
y (float) – North coordinate of the telescope in km.
z (float) – Height of the telescope in km above ground level.
theta (float) – Zenith angle in degrees of the telescope pointing direction.
alt (float) – Altitude in degrees of the telescope pointing direction. If None, theta is used. If given, theta is overwritten.
az (float) – Azimuth angle (from north, clockwise) in degrees of the telescope pointing direction.
efficiency (DataFrame) – If None, the default efficiency of the selected tel_type. If given, the DataFrame should have two columns with wavelength in nm (with constant discretization step) and efficiency (decimal fraction).
apert (float) – Angular diameter in degrees of the telescope field of view.
area (float) – Detection area in m^2 (e.g., mirror area of an IACT).
N_pix (int) – Number of camera pixels.
int_time (float) – Integration time in microseconds of camera frames.

tel_type

Name given to the telescope. Default to None.

Type: str

apert

Angular diameter in degrees of the telescope field of view. Default to 10 degrees.

Type: float

area

Detection area in m^2 (e.g., mirror area of an IACT). Default to 100 m^2.

Type: float

N_pix

Number of camera pixels. Default to 1500.

Type: int

int_time

Integration time in microseconds of camera frames. Default to 0.01 us.

Type: float

sol_angle

Telescope field of view in steradians.

Type: float

sol_angle_pix

Pixel field of view in steradians.

Type: float

apert_pix

Angular diameter in degrees of the pixel FoV.

Type: float

wvl_ini

Initial wavelength in nm of the detection efficiency data. Default to 290 nm.

Type: float

wvl_fin

Final wavelength in nm of the detection efficiency data. Default to 430 nm.

Type: float

wvl_step

Step size in nm of the detection efficiency data. Default to 3 nm.

Type: float

wvl_fluo

Array containing the wavelengths of the 34 fluorescence bands included in the model. See Fluorescence class.

Type: ndarray

eff_fluo

Array containing the detection efficiency at these 34 wavelengths. Default to 1.

Type: ndarray

wvl_cher

Array containing the range of wavelengths in nm defined by wvl_ini, wvl_fin and wvl_step

Type: ndarray

eff_cher

Array containing the detection efficiency data in this range used to compute the Cherenkov signal. Default to 1.

Type: ndarray

x

East coordinate of the telescope in km.

Type: float

y

North coordinate of the telescope in km.

Type: float

z

Height of the telescope in km above ground level.

Type: float

theta

Zenith angle in degrees of the telescope pointing direction.

Type: float

alt

Altitude in degrees of the telescope pointing direction.

Type: float

az

Azimuth angle (from north, clockwise) in degrees of the telescope pointing direction.

Type: float

ux

x coordinate of a unit vector parallel to the telescope pointing direction.

Type: float

uy

y coordinate of a unit vector parallel to the telescope pointing direction.

Type: float

uz

z coordinate of a unit vector parallel to the telescope pointing direction.

Type: float

sin_theta

Sine of theta (cosine of alt).

Type: float

cos_theta

Cosine of theta (sine of alt).

Type: float

sin_az

Sine of az.

Type: float

cos_az

Cosine of az.

Type: float

phi_right

Position angle phi in degrees of the right-hand direction from the telescope point of view.

Type: float

copy(): Copy the Telescope object, but with optional changes.

hor_to_FoV(): Convert cartesian coordinates from horizontal system to FoV system.

FoV_to_hor(): Convert cartesian coordinates from FoV system to horizontal system.

thetaphi_to_altaz(): Convert FoV coordinates theta/phi to horizontal coordinates alt/az.

altaz_to_thetaphi(): Convert horizontal coordinates alt/az to FoV coordinates theta/phi.

spherical(): Calculate the spherical coordinates in both horizontal and FoV systems.

abs_to_rel(): Calculate the x, y, z coordinates relative to the telescope position from the ‘absolute’ x, y, z coordinates.

distance(): Calculate the distance in km between the point x, y, z (‘absolute’ coordinates) and the telescope position.

See also

IACT: IACT class, daughter of Telescope class.
GridElement: GridElement class, daughter of Telescope class.
Observatory: List of telescopes.

class showermodel.telescope.IACT(x=0.0, y=0.0, z=0.0, theta=0.0, alt=None, az=0.0, tel_type='IACT', efficiency=None, apert=None, area=None, N_pix=None, int_time=None)

Bases: Telescope

Daughter class of Telescope.

tel_type is set to ‘IACT’ and the following default values are used: apert = 8 deg, area = 113.097 m^2, N_pix = 1800, wvl_ini = 280 nm, wvl_fin = 600 nm, wvl_step = 3nm

The detection efficiency is taken similar to MST telescopes of CTA.

class showermodel.telescope.GridElement(x=0.0, y=0.0, z=0.0, theta=0.0, alt=None, az=0.0, tel_type='GridElement', efficiency=None, apert=None, area=None, N_pix=None, int_time=None)

Bases: Telescope

Daughter class of Telescope used to calculate ground distributions.

tel_type is set to ‘GridElement’ and the following default values are used: apert = 180 deg, N_pix = 1, int_time = 10 us. The detection efficiency is assumed to be 1.

See also

Grid: Make a rectangular grid of telescopes across the x and y directions.
Shower.show_distribution: Show the light distribution on ground.
Event.show_distribution: Show the light distribution on ground.

Methods:

Telescope.copy(**kwargs)

Copy a Telescope object, but with optional changes.

Parameters: **kwargs ({x, y, z, ...}) – Optional changes to the original telescope attributes, including class attributes.
Returns: telescope
Return type: Telescope

Telescope.hor_to_FoV(x_hor, y_hor, z_hor)

Convert cartesian coordinates from horizontal system to FoV system.

In the FoV coordinates system, x_FoV grows in the right-hand direction, y_FoV grows downward and z_FoV grows toward the pointing direction from the telescope point of view.

Parameters

x_hor (float or array_like) –
y_hor (float or array_like) –
z_hor (float or array_like) –

Returns

x_FoV, y_FoV, z_FoV

Return type

float or array_like

See also

Telescope.FoV_to_hor: Convert cartesian coordinates from FoV system to horizontal system.
Telescope.altaz_to_thetaphi: Convert horizontal coordinates alt, az to FoV coordinates theta, phi.

Telescope.FoV_to_hor(x_FoV, y_FoV, z_FoV)

Convert cartesian coordinates from FoV system to horizontal system.

In the FoV coordinates system, x_FoV grows in the right-hand direction, y_FoV grows downward and z_FoV grows toward the pointing direction from the telescope point of view.

Parameters

x_FoV (float or array_like) –
y_FoV (float or array_like) –
z_FoV (float or array_like) –

Returns

x_hor, y_hor, z_hor

Return type

float or array_like

See also

Telescope.hor_to_FoV: Convert cartesian coordinates from horizontal system to FoV system.
Telescope.thetaphi_to_altaz: Convert FoV coordinates theta, phi to horizontal coordinates alt, az.

Telescope.thetaphi_to_altaz(theta, phi)

Convert FoV coordinates theta, phi to horizontal coordinates alt, az.

Parameters

theta (float or array_like) –
phi (float or array_like) –

Returns

alt, az

Return type

float or array_like

See also

Telescope.FoV_to_hor: Convert cartesian coordinates from FoV system to horizontal system.
Telescope.altaz_to_thetaphi: Convert horizontal coordinates alt, az to FoV coordinates theta, phi.

Telescope.altaz_to_thetaphi(alt, az)

Convert polar horizontal coordinates alt, az to FoV coordinates theta, phi.

Parameters

alt (float or array_like) –
az (float or array_like) –

Returns

theta, phi

Return type

float or array_like

See also

Telescope.hor_to_FoV: Convert cartesian coordinates from horizontal system to FoV system.
Telescope.thetaphi_to_altaz: Convert FoV coordinates theta, phi to horizontal coordinates alt, az.

Telescope.spherical(x, y, z)

Calculate the spherical coordinates in both horizontal and FoV systems from the ‘absolute’ x, y, z coordinates.

Parameters

x (float or array_like) –
y (float or array_like) –
z (float or array_like) –

Returns

distance, alt, az, theta, phi

Return type

float or array_like

Telescope.abs_to_rel(x, y, z): Calculate the x, y, z coordinates relative to the telescope position from the ‘absolute’ x, y, z coordinates.

Telescope.distance(x, y, z)

Calculate the distance in km between the point x, y, z (‘absolute’ coordinates) and the telescope position.

Parameters

x (float or array_like) –
y (float or array_like) –
z (float or array_like) –

Returns

distance

Return type

float or array_like