Alexander Ziegler / ctools

Commit 2a3dae800e418c9a5b3621fda5b829aff9837c9a

Authored by Jürgen Knödlseder
1 parent 89077ba0

Complete glossary

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doc/source/users/glossary.rst
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@@ -5,13 +5,21 @@ Glossary @@ -5,13 +5,21 @@ Glossary
5 5
6 .. topic:: Counts cube 6 .. topic:: Counts cube
7 7
8 - Bla bla ... 8 + A counts cube is a three-dimensional data cube spanned by Right Ascension
  9 + or Galactic longitude, Declination or Galactic latitude, and reconstructed
  10 + energy. The binning is logarithmic in energy.
  11 +
9 12
10 .. _glossary_eventlist: 13 .. _glossary_eventlist:
11 14
12 .. topic:: Event list 15 .. topic:: Event list
13 16
14 - Bla bla ... 17 + An event list is a table comprising the reconstructed properties of the
  18 + observed events. Each row of the table corresponds to an event. The columns
  19 + of the table provide event characteristics, such as trigger time,
  20 + reconstructed arrival direction (in Right Ascension and Declination), and
  21 + the reconstructed event energy.
  22 +
15 23
16 .. _glossary_1dc: 24 .. _glossary_1dc:
17 25
@@ -35,28 +43,96 @@ Glossary @@ -35,28 +43,96 @@ Glossary
35 43
36 .. topic:: Good Time Interval 44 .. topic:: Good Time Interval
37 45
38 - Bla bla ... 46 + A Good Time Interval is a contiguous time period, defined by a start and
  47 + a stop time, during which the events can be used for a scientific analysis.
  48 +
39 49
40 .. _glossary_irf: 50 .. _glossary_irf:
41 51
42 .. topic:: Instrument Response Functions 52 .. topic:: Instrument Response Functions
43 53
44 - Bla bla ... 54 + The instrument response functions provide a mathematical description that
  55 + links the measured quantities of an event to the physical quantities of
  56 + the incident photon. The instrument response functions for CTA are factorised
  57 + into the effective area :math:`A_{\rm eff}(p, E, t)` (units :math:`cm^2`),
  58 + the point spread function :math:`PSF(p' | p, E, t)`,
  59 + and the energy dispersion :math:`E_{\rm disp}(E' | p, E, t)`
  60 + following:
  61 +
  62 + .. math::
  63 + R(p', E', t' | p, E, t) =
  64 + A_{\rm eff}(p, E, t) \times
  65 + PSF(p' | p, E, t) \times
  66 + E_{\rm disp}(E' | p, E, t)
  67 +
45 68
46 .. _glossary_moddef: 69 .. _glossary_moddef:
47 70
48 .. topic:: Model definition file 71 .. topic:: Model definition file
49 72
50 - Bla bla ... 73 + Source and background model components are defined in ctools by a model
  74 + definition file. The model definition file is an ASCII file in XML format.
  75 + The format of the model definition file is inspired from, and is
  76 + compatible with, the format used by the Fermi-LAT Science Tools.
  77 + The general structure of a model definition file is
  78 +
  79 + .. code-block:: xml
  80 +
  81 + <?xml version="1.0" standalone="no"?>
  82 + <source_library title="source library">
  83 + <source name="Crab" type="PointSource">
  84 + <spectrum type="PowerLaw">
  85 + <parameter name="Prefactor" scale="1e-16" value="5.7" min="1e-07" max="1000.0" free="1"/>
  86 + <parameter name="Index" scale="-1" value="2.48" min="0.0" max="+5.0" free="1"/>
  87 + <parameter name="PivotEnergy" scale="1e6" value="0.3" min="0.01" max="1000.0" free="0"/>
  88 + </spectrum>
  89 + <spatialModel type="SkyDirFunction">
  90 + <parameter name="RA" scale="1.0" value="83.6331" min="-360" max="360" free="0"/>
  91 + <parameter name="DEC" scale="1.0" value="22.0145" min="-90" max="90" free="0"/>
  92 + </spatialModel>
  93 + </source>
  94 + <source name="Background" type="CTAIrfBackground" instrument="CTA">
  95 + <spectrum type="PowerLaw">
  96 + <parameter name="Prefactor" scale="1.0" value="1.0" min="1e-3" max="1e+3" free="1"/>
  97 + <parameter name="Index" scale="1.0" value="0.0" min="-5.0" max="+5.0" free="1"/>
  98 + <parameter name="PivotEnergy" scale="1e6" value="1.0" min="0.01" max="1000.0" free="0"/>
  99 + </spectrum>
  100 + </source>
  101 + </source_library>
  102 +
  103 + Each model component is described by the ``<source>`` tag. Each source has
  104 + an mandatory spectral and a spatial component (tags ``<spectrum>`` and
  105 + ``<spatialModel>``) and an optional temporal component (tag ``<temporal>``).
  106 + Parameters that should be adjusted in a maximum likelihood fit should be
  107 + set to ``free="1"``; otherwise they are hold fixed.
  108 +
51 109
52 .. _glossary_obs: 110 .. _glossary_obs:
53 111
54 .. topic:: Observation 112 .. topic:: Observation
55 113
56 - Bla bla ... 114 + The data are split into observations. Each observation is characterised by
  115 + a stable instrument configuration that can be described by an instrument
  116 + response function. Observations are also known as runs.
  117 +
57 118
58 .. _glossary_obsdef: 119 .. _glossary_obsdef:
59 120
60 .. topic:: Observation definition file 121 .. topic:: Observation definition file
61 122
62 - Bla bla ... 123 + Observations are combined in ctools using an observation definition file.
  124 + The observation definition file is an ASCII file in XML format.
  125 + The format of the observation definition file is illustrated below:
  126 +
  127 + .. code-block:: xml
  128 +
  129 + <?xml version="1.0" standalone="no"?>
  130 + <observation_list title="observation library">
  131 + <observation name="Crab" id="00001" instrument="CTA">
  132 + <parameter name="EventList" file="events1.fits"/>
  133 + </observation>
  134 + <observation name="Crab" id="00002" instrument="CTA">
  135 + <parameter name="EventList" file="events2.fits"/>
  136 + </observation>
  137 + </observation_list>
  138 +