21cm cosmology

Literature Review

Most recently I have focused on building and using low frequency radio interferometers that observe the 21 cm line at redshifts z>6, during the Epoch of Reionization (EoR) -the Cosmic Dawn- when the first stars, galaxies and black holes formed and ionized the intergalactic medium. Reionization is the last global phase transition and marks the transition from a cosmological universe, dominated by dark matter to the age of Baryons.

Here are a few popular-press articles and books, sadly some paywalled, consult your local library:


The Precision Array for Probing the Epoch of Reionization (PAPER) was a first generation experiment designed to prototype the methods necessary for observing the fluctuations in the 21cm signal during the Epoch of Reionization (redshifts 6 to 12).  PAPER was a series of test arrays of increasing size built with low cost materials first in Green Bank WV and then at the SKA site in South Africa.

MWA mwatelescope.org

The Murchison Widefield Array is a first generation low frequency radio telescope targeting the 21cm cosmology signal. MWA is a phased array capable of steering its beams anywhere on the sky which makes it capable of doing non-cosmological science as well.  This capability also makes the MWA ideally suited to the mapping of foregrounds to the 21cm signal.

HERA reionization.org

The Hydrogen Epoch of Reionization Array (HERA) is cosmology experiment to directly detect primordial hydrogen dating from the time of the first stars. HERA is a large radio interferometer located in the Karoo desert of South Africa.  At ASU we are contributing in a number of ways but have direct responsibility for the commissioning of the instrument and delivering data products to the collaboration.

ECHO danielcjacobs.com/ECHO

The External Calibrator for Hydrogen Observatories (ECHO) is a drone-mounted calibration source used to map the response of instruments like HERA at the high precision necessary for cosmological observations.

HERA Imaging Group

Students at ASU looking for a research experience can join our Imaging group, a team of students who are working with data from radio telescopes like HERA.  To find out more, email Danny Jacobs (daniel.c.jacobs) or Adam Beardsley (adam.beardsley)  at asu.edu



Space Missions

Advisor and systems engineer to small satellite/cubeat missions.

Phoenix – A student led project funded by the NASA USIP program, Phoenix is a 3U cubesat which will image US cities in thermal infrared.

SPARCS – A mission to measure the UV flare environment of M-dwarf stars.  SPARCS is a 6U UV space telescope.