Results 21 to 30 of about 1,034,573 (296)

Detecting the signature of helium reionization through 3HeII 3.46 cm line-intensity mapping

Astronomy & Astrophysics
Context. Helium reionization is the most recent phase change of the intergalactic medium, yet its timing and main drivers remain uncertain. Among the probes to trace to trace how it unfolds, the 3.46 cm hyperfine line of singly ionized helium has opened ...
Spina Benedetta, Porciani Cristiano, Bosman Sarah E. I., Davies Frederick B., Garaldi Enrico, Keenan Ryan P., Schimd Carlo   +6 more
doaj   +1 more source

Sunyaev-Zeldovich Fluctuations from the First Stars? [PDF]

, 2003
WMAP's detection of high electron-scattering optical depth suggests substantial star formation at high redshift z~17 +/- 5. On the other hand, the recovered sigma_8 ~ 0.84 +/-0.04 disfavors a cluster Sunyaev-Zeldovich (SZ) origin for the observed small ...
Cooray, Asantha, Kamionkowski, Marc, Oh, S. Peng   +2 more
core   +4 more sources

Lyα visibility from z = 4.5 to 11 in the UDS field: Evidence for a high neutral hydrogen fraction and small ionized bubbles at z ∼ 7

Astronomy & Astrophysics
The resonant scattering nature of Lyα photons interacting with neutral hydrogen makes Lyα emitters (LAEs) robust tracers of the intergalactic neutral hydrogen fraction, and thus sensitive probes of cosmic reionization.
Napolitano L., Pentericci L., Dickinson M., Arrabal Haro P., Taylor A. J., Calabrò A., Bhagwat A., Santini P., Arevalo-Gonzalez F., Begley R., Castellano M., Ciardi B., Donnan C. T., Dottorini D., Dunlop J. S., Finkelstein S. L., Fontana A., Giavalisco M., Hirschmann M., Jung I., Koekemoer A. M., Kokorev V., Llerena M., Lucas R. A., Mascia S., Merlin E., Pérez-González P. G., Stanton T. M., Tripodi R., Wang X., Weiner B. J.   +30 more
doaj   +1 more source

Chemical Yields from the First Stars

, 1999
We examine the dependence of stellar yields on the metallicity Z of the stellar population. This effect may be important for the very first chemical enrichment from Population III stars, at very low Z.
Portinari, L.
core   +2 more sources

Formation of the First Stars and Quasars [PDF]

, 1998
We review observable signatures of the first generation of stars and low-luminosity quasars, including the metal enrichment, radiation background, and dust opacity/emission that they produce.
Eisenstein, Elvis, Fixsen, Gunn, Haehnelt, Haiman, Haiman, Haiman, Haiman, Haiman, Haiman, Haiman, Hu, Kormendy, Kurucz, Loeb, Loeb, Mather, Mathis, Miller, Ostriker, Pei, Press, Press, Sasaki, Scalo, Schaller, Songaila, Songaila, Tytler, Z Haiman, Zaldarriaga   +31 more
core   +3 more sources

Rotation Speed of the First Stars

, 2010
We estimate the rotation speed of Population III (Pop III) stars within a minihalo at z ~ 20 using a smoothed particle hydrodynamics (SPH) simulation, beginning from cosmological initial conditions.
Abel, Abraham Loeb, Alvarez, Athena Stacy, Balbus, Barkana, Bate, Bate, Belczynski, Bodenheimer, Boss, Boss, Bromm, Bromm, Bromm, Bromm, Bromm, Bromm, Bromm, Bromm, Bromm, Caselli, Cesaroni, Ciardi, Clark, Clark, Duquennoy, Ekström, Ekström, Frebel, Frebel, Fryer, Glover, Goodman, Gou, Greif, Greif, Greif, Haiman, Heger, Heger, Heger, Huang, Izzard, Jappsen, Johnson, Kitayama, Koenigl, Kratter, Kraus, Krumholz, Kudritzki, Lee, Lee, Loeb, Machida, Madau, Maeder, Maeder, Maki, Martel, Matt, Mori, Naoz, Narayan, Nomoto, Norman, Nugis, Omukai, Omukai, Papaloizou, Petrovic, Salvaterra, Schleicher, Schneider, Shu, Silk, Simon, Sokasian, Spitzer, Springel, Springel, Spruit, Stacy, Stahler, Suwa, Tan, Tan, Tanvir, Tegmark, Tornatore, Turk, Ulrich, Volker Bromm, Wada, Whalen, Wise, Wolff, Woosley, Woosley, Woosley, Xu, Yoon, Yoshida, Yoshida, Zhang   +105 more
core   +1 more source

Formation of the First Stars by Accretion [PDF]

, 2003
The process of star formation from metal-free gas is investigated by following the evolution of accreting protostars with emphasis on the properties of massive objects.
Francesco Palla, Kahn F. D., Kazuyuki Omukai, Larson R. B., Larson R. B., Tomisaka K.   +5 more
core   +2 more sources

Measuring the intergalactic medium correlation length at 5 < z < 6.1: A fast change at the end of reionization

Astronomy & Astrophysics
Context. The Lyman-α forest of high-redshift quasars is a powerful probe of the late stages of the epoch of reionization (EoR), in particular thanks to the presence of Gunn-Peterson troughs.
Spina Benedetta, Bosman Sarah E. I., Maity Barun, Davies Frederick B.   +3 more
doaj   +1 more source

The Effect of Dark Matter on the First Stars: A New Phase of Stellar Evolution

, 2007
Dark matter (DM) in protostellar halos can dramatically alter the current theoretical framework for the formation of the first stars. Heat from supersymmetric DM annihilation can overwhelm any cooling mechanism, consequently impeding the star formation ...
Freese, Katherine, Gondolo, Paolo, Spolyar, Douglas   +2 more
core   +1 more source

The 21cm Signature of the First Stars [PDF]

, 2006
We predict the 21-cm signature of the first metal-free stars. The soft X-rays emitted by these stars penetrate the atomic medium around their host halos, generating Lyman alpha photons that couple the spin and kinetic temperatures. These creates a region
Barkana R., Ciardi B., Hummer D. G., Jordi Miralda‐Escudé, Mo H. J., Reed D. S., Storey P. J., Xuelei Chen   +7 more
core   +4 more sources