/usr/share/doc/stilts/sun256/uk.ac.starlink.ttools.func.Distances.html is in stilts-doc 3.1.2-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 | <html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<link rel="stylesheet" type="text/css" href="sun-style.css">
<title>Distances</title>
</head>
<body>
<hr>
<a href="uk.ac.starlink.ttools.func.Times.html">Next</a> <a href="uk.ac.starlink.ttools.func.Fluxes.html">Previous</a> <a href="staticMethods.html">Up</a> <a href="index.html">Contents</a> <br> <b>Next: </b><a href="uk.ac.starlink.ttools.func.Times.html">Times</a><br>
<b>Up: </b><a href="staticMethods.html">Functions</a><br>
<b>Previous: </b><a href="uk.ac.starlink.ttools.func.Fluxes.html">Fluxes</a><br>
<hr>
<h4><a name="uk.ac.starlink.ttools.func.Distances">10.5.4 Distances</a></h4>
<p>Functions for converting between different measures of cosmological
distance.
</p>
<p>The following parameters are used:
<ul>
<li><strong>z</strong>: redshift
</li>
<li><strong>H0</strong>: Hubble constant in km/sec/Mpc
(example value ~70)
</li>
<li><strong>omegaM</strong>: Density ratio of the universe
(example value 0.3)
</li>
<li><strong>omegaLambda</strong>: Normalised cosmological constant
(example value 0.7)
</li>
</ul>
</p>
<p>For a flat universe, <code>omegaM</code>+<code>omegaLambda</code>=1
</p>
<p>The terms and formulae used here are taken from the
paper by D.W.Hogg, <em>Distance measures in cosmology</em>,
<a href="http://arxiv.org/abs/astro-ph/9905116">astro-ph/9905116</a> v4
(2000).
</p>
<p>
<dl>
<dt><strong><code>MpcToM( distMpc )</code></strong></dt>
<dd>Converts from MegaParsecs to metres.
<ul>
<li><code>distMpc</code> <em>(floating point)</em>: distance in Mpc
</li>
<li>return value <em>(floating point)</em>: distance in m
</li>
</ul>
</dd>
<dt><strong><code>mToMpc( distM )</code></strong></dt>
<dd>Converts from metres to MegaParsecs.
<ul>
<li><code>distM</code> <em>(floating point)</em>: distance in m
</li>
<li>return value <em>(floating point)</em>: distance in Mpc
</li>
</ul>
</dd>
<dt><strong><code>zToDist( z )</code></strong></dt>
<dd>Quick and dirty function for converting from redshift to distance.
<p><strong>Warning</strong>: this makes some reasonable
assumptions about the cosmology and returns the luminosity
distance. It is only intended for approximate use. If you care
about the details, use one of the more specific functions here.
<ul>
<li><code>z</code> <em>(floating point)</em>: redshift
</li>
<li>return value <em>(floating point)</em>: some distance measure in Mpc
</li>
</ul>
</p>
</dd>
<dt><strong><code>zToAge( z )</code></strong></dt>
<dd>Quick and dirty function for converting from redshift to time.
<p><strong>Warning</strong>: this makes some reasonable
assumptions about the cosmology. It is only intended for approximate
use. If you care about the details use one of the more specific
functions here.
<ul>
<li><code>z</code> <em>(floating point)</em>: redshift
</li>
<li>return value <em>(floating point)</em>: 'age' of photons from redshift <code>z</code> in Gyr
</li>
</ul>
</p>
</dd>
<dt><strong><code>comovingDistanceL( z, H0, omegaM, omegaLambda )</code></strong></dt>
<dd>Line-of-sight comoving distance.
<ul>
<li><code>z</code> <em>(floating point)</em>: redshift
</li>
<li><code>H0</code> <em>(floating point)</em>: Hubble constant in km/sec/Mpc
</li>
<li><code>omegaM</code> <em>(floating point)</em>: density ratio of the universe
</li>
<li><code>omegaLambda</code> <em>(floating point)</em>: normalised cosmological constant
</li>
<li>return value <em>(floating point)</em>: line-of-sight comoving distance in Mpc
</li>
</ul>
</dd>
<dt><strong><code>comovingDistanceT( z, H0, omegaM, omegaLambda )</code></strong></dt>
<dd>Transverse comoving distance.
<ul>
<li><code>z</code> <em>(floating point)</em>: redshift
</li>
<li><code>H0</code> <em>(floating point)</em>: Hubble constant in km/sec/Mpc
</li>
<li><code>omegaM</code> <em>(floating point)</em>: density ratio of the universe
</li>
<li><code>omegaLambda</code> <em>(floating point)</em>: normalised cosmological constant
</li>
<li>return value <em>(floating point)</em>: transverse comoving distance in Mpc
</li>
</ul>
</dd>
<dt><strong><code>angularDiameterDistance( z, H0, omegaM, omegaLambda )</code></strong></dt>
<dd>Angular diameter distance.
<ul>
<li><code>z</code> <em>(floating point)</em>: redshift
</li>
<li><code>H0</code> <em>(floating point)</em>: Hubble constant in km/sec/Mpc
</li>
<li><code>omegaM</code> <em>(floating point)</em>: density ratio of the universe
</li>
<li><code>omegaLambda</code> <em>(floating point)</em>: normalised cosmological constant
</li>
<li>return value <em>(floating point)</em>: angular diameter distance in Mpc
</li>
</ul>
</dd>
<dt><strong><code>luminosityDistance( z, H0, omegaM, omegaLambda )</code></strong></dt>
<dd>Luminosity distance.
<ul>
<li><code>z</code> <em>(floating point)</em>: redshift
</li>
<li><code>H0</code> <em>(floating point)</em>: Hubble constant in km/sec/Mpc
</li>
<li><code>omegaM</code> <em>(floating point)</em>: density ratio of the universe
</li>
<li><code>omegaLambda</code> <em>(floating point)</em>: normalised cosmological constant
</li>
<li>return value <em>(floating point)</em>: luminosity distance in Mpc
</li>
</ul>
</dd>
<dt><strong><code>lookbackTime( z, H0, omegaM, omegaLambda )</code></strong></dt>
<dd>Lookback time. This returns the difference between the age of
the universe at time of observation (now) and the age of the
universe at the time when photons of redshift <code>z</code>
were emitted.
<ul>
<li><code>z</code> <em>(floating point)</em>: redshift
</li>
<li><code>H0</code> <em>(floating point)</em>: Hubble constant in km/sec/Mpc
</li>
<li><code>omegaM</code> <em>(floating point)</em>: density ratio of the universe
</li>
<li><code>omegaLambda</code> <em>(floating point)</em>: normalised cosmological constant
</li>
<li>return value <em>(floating point)</em>: lookback time in Gyr
</li>
</ul>
</dd>
<dt><strong><code>comovingVolume( z, H0, omegaM, omegaLambda )</code></strong></dt>
<dd>Comoving volume. This returns the all-sky total comoving
volume out to a given redshift <code>z</code>.
<ul>
<li><code>z</code> <em>(floating point)</em>: redshift
</li>
<li><code>H0</code> <em>(floating point)</em>: Hubble constant in km/sec/Mpc
</li>
<li><code>omegaM</code> <em>(floating point)</em>: density ratio of the universe
</li>
<li><code>omegaLambda</code> <em>(floating point)</em>: normalised cosmological constant
</li>
<li>return value <em>(floating point)</em>: comoving volume in Gpc<sup>3</sup></li>
</ul>
</dd>
<dt><strong><code>SPEED_OF_LIGHT</code></strong></dt>
<dd>Speed of light in m/s.
<ul></ul>
</dd>
<dt><strong><code>METRE_PER_PARSEC</code></strong></dt>
<dd>Number of metres in a parsec.
<ul></ul>
</dd>
<dt><strong><code>SEC_PER_YEAR</code></strong></dt>
<dd>Number of seconds in a year.
<ul></ul>
</dd>
</dl>
</p>
<hr><a href="uk.ac.starlink.ttools.func.Times.html">Next</a> <a href="uk.ac.starlink.ttools.func.Fluxes.html">Previous</a> <a href="staticMethods.html">Up</a> <a href="index.html">Contents</a> <br> <b>Next: </b><a href="uk.ac.starlink.ttools.func.Times.html">Times</a><br>
<b>Up: </b><a href="staticMethods.html">Functions</a><br>
<b>Previous: </b><a href="uk.ac.starlink.ttools.func.Fluxes.html">Fluxes</a><br>
<hr><i>STILTS - Starlink Tables Infrastructure Library Tool Set<br>Starlink User Note256<br>STILTS web page:
<a href="http://www.starlink.ac.uk/stilts/">http://www.starlink.ac.uk/stilts/</a><br>Author email:
<a href="mailto:m.b.taylor@bristol.ac.uk">m.b.taylor@bristol.ac.uk</a><br>Mailing list:
<a href="mailto:topcat-user@jiscmail.ac.uk">topcat-user@jiscmail.ac.uk</a><br></i></body>
</html>
|