# # Compare to fig 5, page 512, of # Carroll, Press & Turner, ARAA, 1992, 30, 499-542 # use strict; use PDL; use PDL::Graphics::PGPLOT::Window; use Astro::Cosmology; # cosmologies - h0 is irrelevant here my $a = Astro::Cosmology->new( matter => 1.0, lambda => 0.0, h0 => 0.0 ); my $b = Astro::Cosmology->new( matter => 0.1, lambda => 0.0, h0 => 0.0 ); my $c = Astro::Cosmology->new( matter => 0.1, lambda => 0.9, h0 => 0.0 ); my $d = Astro::Cosmology->new( matter => 0.01, lambda => 0.0, h0 => 0.0 ); my $e = Astro::Cosmology->new( matter => 0.01, lambda => 0.99, h0 => 0.0 ); # z range my $lz = 0.1 * (sequence(31) - 15); my $z = 10**($lz); # calculate the normalised angular-diameter distances my $d_a = $a->adiam_dist( $z ); my $d_b = $b->adiam_dist( $z ); my $d_c = $c->adiam_dist( $z ); my $d_d = $d->adiam_dist( $z ); my $d_e = $e->adiam_dist( $z ); my $ld_a = log10( $d_a ); my $ld_b = log10( $d_b ); my $ld_c = log10( $d_c ); my $ld_d = log10( $d_d ); my $ld_e = log10( $d_e ); # plot the graph my $win = PDL::Graphics::PGPLOT::Window->new(); $win->env( log10(0.03), log10(32), log10(0.03), log10(1), 0, 30 ); $win->label_axes( "redshift z", "angular diameter distance H\\d0\\ud\\dA\\u", "Fig 5 of Carroll, Press & Turner ARAA 1992 v30, p499 " . "[Astro::Cosmology v" .Astro::Cosmology->version. "]" ); $win->hold; $win->line( $lz, $ld_a, { LINESTYLE => 'solid' } ); $win->line( $lz, $ld_b, { LINESTYLE => 'dashed' } ); $win->line( $lz, $ld_c, { LINESTYLE => 'dot-dash' } ); $win->line( $lz, $ld_d, { LINESTYLE => 'dotted' } ); $win->line( $lz, $ld_e, { LINESTYLE => 'dash-dot-dot' } ); $win->release; $win->close; ## End of the test exit;