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Light Sources
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This chapter aims to summarize the light sources in the ICEHAP labs.
If you find this page to be incomplete, please add your lightsource.


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Laser and optical bench
=======================

The lightsource used for the gain calibrations and 2D scans is a Hamamatsu
laser. The laser is mounted inside a darkbox shown in :numref:`laser_darkbox`.

.. _laser_darkbox:
.. figure:: ../../images/instruments/lightsources/laserbox_closed.png
    :align: right

    The closed darkbox containing the laser, optical bench and reference PMT
    setup.

The laser is controlled by the powersupply shown in :numref:`laser_controller`.

.. _laser_controller:
.. figure:: ../../images/instruments/lightsources/laser_controller.png
    :align: right

    The laser controller, laser intensity and pulse frequency can be set.
    A cable is connected to the external trigger out.

The laser is mounted to an optical table as shown in :numref:`optical_bench`.
There is a static 1% filter, as well as an adjustable filter wheel in the
beamline. After that, the beam is split into signal and reference line with
a beamsplitter. The beams are coupled into optical fibers, which lead to a
small box inside the laserbox as well as the 2D scan box.

.. _optical_bench:
.. figure:: ../../images/instruments/lightsources/optical_bench.png
    :align: right

    The optical bench inside the laser darkbox.

The reference line ends in a collimator, which is directed onto a reference PMT.
That setup is shown in :numref:`ref_PMT_setup`.

.. _ref_PMT_setup:
.. figure:: ../../images/instruments/lightsources/reference_PMT_laserbox.png
    :align: right

    The reference PMT mount within the laser darkbox.

The signal line ends in the 2D scan box, the collimator is mounted to a
driveable Zenith, Azimuth stage. The closed scan box is shown in
:numref:`closed_2D_scan_box`.

.. _closed_2D_scan_box:
.. figure:: ../../images/instruments/lightsources/Scanbox_covered.png
    :align: right

    The covered 2D scan box.