Results 61 to 70 of about 14,115,145 (304)
Formation of the first stars and quasars [PDF]
Advances in Space Research, 1999 10 pages, 5 figures included. Invited talk at the 32nd COSPAR Scientific Assemby, 15-17 July, 1998, Nagoya, Japan; to appear in Adv.
openaire +2 more sources
OBSERVATIONAL SIGNATURES OF THE FIRST STARS [PDF]
, 2001 At present, there are several feasible observational probes of the first stars in the universe. Here, we examine the constraints on early stellar activity from the metallicity of the high-redshift Ly-$α$ clouds, from the effects of stellar ionizing photons on reionization and the cosmic microwave background (CMB), and from the implications of ...
Venkatesan, Aparna, Truran, James W.
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Zero-Metallicity Stars and the Effects of the First Stars on Reionization [PDF]
The Astrophysical Journal, 2000 We present stellar structure and atmosphere models of metal-free stars and examine them from a cosmological point of view. Metal-free stars exhibit high effective temperatures and small sizes relative to metal-enriched stars of equal mass. These unique physical characteristics enhance the ionizing photon production by metal-free stars, particularly in ...
Tumlinson, Jason, Shull, J. Michael
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UV slopes of star-forming galaxies in strong-lensing fields at the epoch of reionisation with JWST
Astronomy & AstrophysicsContext. UV slopes (β) are a powerful diagnostic for galaxies at the epoch of reionisation, tracing star formation, interstellar medium ionisation, and the escape fraction fesc of ionising photons.
Felicioni Giordano +22 more
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Stellar Properties of Observed Stars Stripped in Binaries in the Magellanic Clouds
The Astrophysical Journal, 2023 Massive stars (∼8–25 M _⊙ ) stripped of their hydrogen-rich envelopes via binary interaction are thought to be the main progenitors for merging neutron stars and stripped-envelope supernovae.
Y. Götberg +8 more
doaj +1 more source
Referral Patterns and Diagnostic Timeliness in Pediatric Cancer: A Hospital‐Based Study in Indonesia
Pediatric Blood &Cancer, EarlyView.ABSTRACT Background Timely diagnosis and treatment are critical for improving survival among children with cancer. In low‐ and middle‐income countries (LMICs), delays are common and may be influenced by fragmented referral pathways and diagnostic limitations.
Nur Melani Sari +5 more
wiley +1 more source
Photometry of 10 Million Stars from the First Two Years of TESS Full Frame Images - Part I [PDF]
, 2020 The Transiting Exoplanet Survey Satellite (TESS) is the first high-precision full-sky photometric survey in space. We extracted light curves from a magnitude limited set of stars and other stationary luminous objects from the TESS Full Frame Images using
Pal, Andras +10 more
core +1 more source
Dark stars: a new study of the first stars in the Universe [PDF]
New Journal of Physics, 2009 We have proposed that the first phase of stellar evolution in the history of the Universe may be Dark Stars (DS), powered by dark matter heating rather than by nuclear fusion. Weakly Interacting Massive Particles, which may be their own antipartners, collect inside the first stars and annihilate to produce a heat source that can power the stars.
Freese, Katherine +3 more
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Theoretical results of one class of multiderivative methods through order stars [PDF]
, 2011 Order stars are applied to Brown (K,L) methods. They are displayed pictorially for a selection of methods and are used to provide succinct proofs of existing results.
Meneguette, Messias +6 more
core +3 more sources
Astronomy & AstrophysicsContext. The 21cm–galaxy cross-correlations are expected to play a key role in the confirmation of the cosmological 21cm signal. Aims. We investigate which survey configurations detect the 21cm–Lyman-α emitter (LAE) cross-correlation signal and assess ...
Hutter Anne, Heneka Caroline
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