Results 51 to 60 of about 94,086 (264)
Gaia Space Mission and Quasars
Frontiers in Astronomy and Space Sciences, 2017 Quasars are often considered to be point-like objects. This is largely true and allows for an excellent alignment of the optical positional reference frame of the ongoing ESA mission Gaia with the International Celestial Reference Frame.
Tomaž Zwitter
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Subaru High-z Exploration of Low-luminosity Quasars (SHELLQs). VI. Black Hole Mass Measurements of Six Quasars at 6.1 ≤ z ≤ 6.7 [PDF]
Astrophysical Journal, 2019 We present deep near-infrared spectroscopy of six quasars at 6.1 ≤ z ≤ 6.7 with Very Large Telescope/X-Shooter and Gemini-N/GNIRS. Our objects, originally discovered through a wide-field optical survey with the Hyper Suprime-Cam (HSC) Subaru Strategic ...
M. Onoue +16 more
semanticscholar +1 more source
What makes red quasars red? Observational evidence for dust extinction from line ratio analysis
, 2017 Red quasars are very red in the optical through near-infrared (NIR) wavelengths, which is possibly due to dust extinction in their host galaxies as expected in a scenario in which red quasars are an intermediate population between merger-driven star ...
Im, Myungshin, Kim, Dohyeong
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The Infrared Traced Star Formation Rates of Associated Absorption Lines Quasars
The Astrophysical JournalSome optically selected quasars exhibit Mg ii- associated absorption lines (AALs), and their origin remains unclear. In this paper, we compile a sample of 1769 quasars, with or without Mg ii AALs, of which 1689 are far-infrared (FIR) detected quasars and
Zhe-Geng Chen +6 more
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Shedding New Light on Weak Emission-line Quasars in the C iv–Hβ Parameter Space
The Astrophysical Journal, 2023 Weak emission-line quasars (WLQs) are a subset of type 1 quasars that exhibit extremely weak Ly α + N v λ 1240 and/or C iv λ 1549 emission lines. We investigate the relationship between emission-line properties and accretion rate for a sample of 230 ...
Trung Ha +22 more
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Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs). VIII. A less biased view of the early co-evolution of black holes and host galaxies [PDF]
Nippon Tenmon Gakkai obun kenkyu hokoku, 2019 We present ALMA [C ii] line and far-infrared (FIR) continuum observations of three $z \gt 6$ low-luminosity quasars ($M_{\rm 1450} \gt -25$ mag) discovered by our Subaru Hyper Suprime-Cam (HSC) survey.
T. Izumi +26 more
semanticscholar +1 more source
Obscuration by Gas and Dust in Luminous Quasars [PDF]
, 2014 We explore the connection between absorption by neutral gas and extinction by dust in mid-infrared (IR) selected luminous quasars. We use a sample of 33 quasars at redshifts 0.7 < z < 3 in the 9 deg^2 Bo\"otes multiwavelength survey field that are ...
Brodwin, Mark +3 more
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Plasmonic Enhancement of Fluorescence and Protein Dynamics in Living Mammalian Cells
Advanced Materials, EarlyView.This study demonstrates plasmonic enhancement of the function of fluorescent voltage sensing proteins (genetically encoded voltage indicators, (GEVIs), QuasAr6) in live mammalian cells. Coupling to plasmonic nanoparticles does not just increase fluorescence, but influences the protein photocycle, creating a hybrid sensor with its response speed to ...
Marco Locarno +16 more
wiley +1 more source
The Astrophysical JournalWe present an analysis of near-infrared photometry of 59 quasars at 5.83 −24 mag) of the sample. This luminosity trend may support the idea that red quasars represent an evolutionary stage preceding unobscured quasars, often invoked in the merger-driven
Ryo Iwamoto +10 more
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Quasar Luminosity Function at z = 7
The Astrophysical Journal Letters, 2023 We present the quasar luminosity function (LF) at z = 7, measured with 35 spectroscopically confirmed quasars at 6.55 < z < 7.15. The sample of 22 quasars from the Subaru High- z Exploration of Low-Luminosity Quasars (SHELLQs) project, combined with 13 ...
Yoshiki Matsuoka +43 more
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