Small-scale primordial fluctuations in the 21 cm Dark Ages signal
نویسندگان
چکیده
منابع مشابه
Redshifted 21-cm Signals in the Dark Ages
We have carried out semianalytic simulations to build redshifted 21-cm maps in the dark ages. An entropy-floor model is adopted for planting protogalaxies in simulated minihaloes. The model allocates gas quantities such as baryonic mass and temperature to every N -body particle and extensively exploits the particle nature of the data in the subsequent analysis. We have found that the number den...
متن کاملLensing of 21-cm fluctuations by primordial gravitational waves.
Weak-gravitational-lensing distortions to the intensity pattern of 21-cm radiation from the dark ages can be decomposed geometrically into curl and curl-free components. Lensing by primordial gravitational waves induces a curl component, while the contribution from lensing by density fluctuations is strongly suppressed. Angular fluctuations in the 21-cm background extend to very small angular s...
متن کاملDo Small-Scale Dark Matter Fluctuations Govern the Fragmentation of Primordial Gas?
In order to constrain the initial mass function of the first generation of stars (Population III), one has to study the fragmentation properties of primordial gas. We present results from 3D simulations, based on Smoothed Particle Hydrodynamics, which explore the idea that small-scale fluctuations in the (cold) dark matter recreate a filamentary and clumpy structure in the gas component on scal...
متن کاملProbing the Dark Ages at Z~20: The SCI-HI 21 cm All-Sky Spectrum Experiment
We present first results from the SCI-HI experiment, which we used to measure the all-sky-averaged 21 cm brightness temperature in the redshift range 14.8 < z < 22.7. The instrument consists of a single broadband sub-wavelength size antenna and a sampling system for real-time data processing and recording. Preliminary observations were completed in 2013 June at Isla Guadalupe, a Mexican biosphe...
متن کاملOn the Direct Detectability of the Cosmic Dark Ages: 21-cm Emission from Minihalos
In the standard Cold Dark Matter (CDM) theory of structure formation, virialized minihalos (with Tvir . 10 4 K) form in abundance at high redshift (z > 6), during the cosmic “dark ages.” The hydrogen in these minihalos, the first nonlinear baryonic structures to form in the universe, is mostly neutral and sufficiently hot and dense to emit strongly at the 21-cm line. We calculate the emission f...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2020
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/staa3638