Movies: First Stars at Redshift 20
Movie page: The signature of the first stars in atomic hydrogen at redshift 20

Eli Visbal (Harvard) [link] , Rennan Barkana (Tel Aviv University) [link] , Anastasia Fialkov (Tel Aviv University) [link] , Dmitriy Tseliakhovich (Caltech) [link] & Chris Hirata (Caltech) [link]

Nature, advanced online publication on June 20'th 2012


The following movies use the same simulated volume as on the Image page (i.e., a different box from the one used in the figures in Nature, with a different set of random initial conditions). Each image within each movie shows a slice that is 384 comoving Mpc on a side, corresponding to 1.25 billion light years in today's Universe. The thickness of the slice is 3 comoving Mpc (9.8 million light years). In each movie, we compare the new prediction (including the effect of both velocity and density) on the left to the previous (density-only) expectation on the right. Both movies show the intensity of radio waves from hydrogen atoms at a wavelength of 21 cm, as expressed in equivalent temperature units (i.e., the brightness temperature, measured here in units of millikelvin). Gas that is hotter than the cosmic microwave background emits 21-cm radiation and has a positive brightness temperature, while colder gas absorbs 21-cm radiation and has a negative brightness temperature. The 21-cm intensity measures the distribution of stars through its sensitivity mainly to the gas temperature (though it is also proportional to the gas density). Regions with a high density of stars have had a higher intensity of X-rays, and thus are hotter and emit more intense 21-cm radiation.

Please note: We provide the movies in two different formats. Some formats may not display properly depending on your particular computer hardware and software. It may work better to download the linked files and open them outside the web browser.

Movie 1

This movie shows the evolution of the 21 cm intensity with time. We indicate the redshift in the upper left of each frame. The redshift indicates cosmic age (higher redshifts correspond to earlier times), such that the Universe has expanded by a factor of 1+z from redshift z until today. The movie spans z=29.98 (a cosmic age of 102 million years) through z=19.3 (192 million years).

Movie files: MP4 format , AVI format .

The initial frame of the movie:

The final frame of the movie:

Movie 2

This movie shows the 21 cm intensity from hydrogen at a cosmic age of 180 million years (i.e., redshift 20). Instead of showing just one slice, the movie travels once through the entire simulation cube (i.e., the motion is into the page, perpendicular to the slice).

Movie files: MP4 format , AVI format .

The initial and final frames of the movie: (They are identical, since the box is periodic)