HST-COS OBSERVATIONS OF AGNs. III. SPECTRAL CONSTRAINTS IN THE LYMAN CONTINUUM FROM COMPOSITE COS/G140L DATA
نویسندگان
چکیده
منابع مشابه
Essential observations of the Lyman continuum
Concurrent observations of Lyman continuum (LyC) and Lyman α (Lyα) emission escaping from star-forming systems at low redshift are essential to understanding the physics of reionization at high redshift (z & 6). Some have suggested reionization is dominated by numerous small galaxies with LyC escape fractions fe ∼ 10%, while others suggest mini-quasars with higher fe might also play a role. At ...
متن کاملAn HST Search for Lyman Continuum Emission From Galaxies at 1 . 1 < z < 1 . 4
If enough of their Lyman limit continuum escapes, star-forming galaxies could be significant contributors to the cosmic background of ionizing photons. To investigate this possibility, we obtained the first deep imaging in the far ultraviolet of eleven bright blue galaxies at intermediate redshift (1.1 < z < 1.4) with the STIS FUV MAMA detector on the Hubble Space Telescope. No Lyman continuum ...
متن کاملThe Lyman continuum radiation escaping from galaxies
The Hα luminosity density of galaxies is used to calculate the local diffuse radiation field at the Lyman limit as resulting from star formation in the universe. The fraction of Lyman continuum radiation leaking out from galaxies through their neutral hydrogen is the most uncertain parameter of the calculation. A comparison of the diffuse radiation predicted from galaxies with that measured fro...
متن کاملthe role of russia in transmission of energy from central asia and caucuses to european union
پس ازفروپاشی شوروی،رشد منابع نفت و گاز، آسیای میانه و قفقاز را در یک بازی ژئوپلتیکی انرژی قرار داده است. با در نظر گرفتن این منابع هیدروکربنی، این منطقه به یک میدانجنگ و رقابت تجاری برای بازی های ژئوپلتیکی قدرت های بزرگ جهانی تبدیل شده است. روسیه منطقه را به عنوان حیات خلوت خود تلقی نموده و علاقمند به حفظ حضورش می باشد تا همانند گذشته گاز طبیعی را به وسیله خط لوله مرکزی دریافت و به عنوان یک واس...
15 صفحه اولLyman “bump” galaxies - I. Spectral energy distribution of galaxies with an escape of nebular Lyman continuum
It is essential to know galactic emissivity and spectrum of Lyman continuum (LyC) in order to understand the cosmic reionization. Here we consider an escape of nebular LyC from galaxies and examine the consequent spectral energy distribution. It is usually assumed that hydrogen nebular LyC mostly produced by bound-free transitions is consumed within photo-ionized nebulae (so-called “on-the-spot...
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: The Astrophysical Journal
سال: 2016
ISSN: 1538-4357
DOI: 10.3847/0004-637x/817/1/56