Results 111 to 120 of about 17,110 (224)

How many radio-loud quasars can be detected by the gamma-ray large area space telescope?

, 2008
In the unification scheme, radio quasars and FR II radio galaxies come from the same parent population, but viewed at different angles. Based on the Comptonization models for the gamma-ray emission from active galactic nuclei (AGNs), we estimate the ...
Bai, J. M., Cao, Xinwu
core  

A Surprising Excess of Radio Emission in Extremely Stable Quasars: A Unique Clue to Jet Launching?

The Astrophysical Journal
Quasars are generally divided into jetted radio-loud and nonjetted radio-quiet ones, but why only 10% of quasars are radio-loud has been puzzling for decades.
Wen-Yong Kang, Jun-Xian Wang, Zhen-Yi Cai, Hao-Chen Wang, Wen-Ke Ren, Mai Liao, Feng Yuan, Andrzej Zdziarski, Xinwu Cao   +8 more
doaj   +1 more source

Euclid: Discovery of 31 new quasars at 6.6 < z < 7.8★

Astronomy & Astrophysics
We report the discovery of 31 new high-z quasars in the redshift range 6.6 
Yang D., Hennawi J. F., Guarneri F., Wolf J., Belladitta S., Schindler J.-T., Hughes A. C. N., Bañados E., Mortlock D. J., Yang J., Wang F., Fan X., Jahnke K., Stern D., Willott C. J., Barth A. J., Rottgering H. J. A., Varadaraj R. G., Decarli R., Eilers A.-C., Ezziati M., Fu Y., Huang J., Jin X., Kang Y., Martinez-Ramirez L. N., Matsuoka Y., Onoue M., Pello R., Remigio R. P., Tee W. L., Venemans B., Vietri G., Wang B., Abbo L. J., Atek H., Bisogni S., Bosman S. E. I., Bowler R. A. A., Conselice C. J., Davies F. B., Gutierrez C. M., Harikane Y., Rubinur K., Lovell C. C., Magliocchetti M., Matthee J., Ricci F., Scialpi M., Scott D., Spinoglio L., Tarsitano F., Toba Y., Walter F., Weaver J. R., Zamorani G., Altieri B., Amara A., Andreon S., Aussel H., Baccigalupi C., Baldi M., Balestra A., Bardelli S., Battaglia P., Biviano A., Branchini E., Brescia M., Camera S., Cañas-Herrera G., Capobianco V., Carbone C., Carretero J., Castellano M., Castignani G., Cavuoti S., Chambers K. C., Cimatti A., Colodro-Conde C., Congedo G., Conversi L., Copin Y., Courbin F., Courtois H. M., Cropper M., Cuillandre J.-C., Degaudenzi H., De Lucia G., Dolding C., Dole H., Douspis M., Dubath F., Dupac X., Dusini S., Escoffier S., Farina M., Farinelli R., Ferriol S., Finelli F., Fourmanoit N., Frailis M., Franceschi E., Fumana M., Galeotta S., George K., Gillis B., Giocoli C., Gómez-Alvarez P., Gracia-Carpio J., Grazian A., Grupp F., Guzzo L., Gwyn S., Haugan S. V. H., Hoekstra H., Holmes W., Hook I. M., Hormuth F., Hornstrup A., Jhabvala M., Kermiche S., Kubik B., Kuijken K., Kümmel M., Kunz M., Kurki-Suonio H., Le Brun A. M. C., Ligori S., Lilje P. B., Lindholm V., Lloro I., Mainetti G., Maino D., Maiorano E., Mansutti O., Marggraf O., Martinelli M., Martinet N., Marulli F., Massey R. J., McCracken H. J., Medinaceli E., Mei S., Mellier Y., Meneghetti M., Merlin E., Meylan G., Mohr J. J., Mora A., Moresco M., Moscardini L., Munari E., Nakajima R., Neissner C., Nichol R. C., Niemi S.-M., Padilla C., Paltani S., Pasian F., Pedersen K., Percival W. J., Pettorino V., Pires S., Polenta G., Poncet M., Popa L. A., Pozzetti L., Racca G. D., Raison F., Rebolo R., Renzi A., Rhodes J., Riccio G., Rix H.-W., Romelli E., Roncarelli M., Rosset C., Rusholme B., Saglia R., Sakr Z., Sapone D., Sauvage M., Schirmer M., Schneider P., Schrabback T., Secroun A., Seidel G., Serrano S., Sihvola E., Simon P., Sirignano C., Sirri G., Stanco L., Steinwagner J., Tallada-Crespí P., Tereno I., Tessore N., Toft S., Toledo-Moreo R., Torradeflot F., Tutusaus I., Valenziano L., Valiviita J., Vassallo T., Wang Y., Weller J., Zerbi F. M., Zucca E., Fabbian G., Huertas-Company M., Martín-Fleitas J., Monaco P., Scottez V., Viel M.   +213 more
doaj   +1 more source

Tracing the massive inflows feeding super-massive black holes in quasars. [PDF]

Innovation (Camb), 2023
Jiang P, Shi X, Zhou H.
europepmc   +1 more source

Quasars Probing Quasars: The Circumgalactic Medium Surrounding z ~ 2 Quasars [PDF]

, 2017
Models of galaxy formation make the most direct predictions on gas related processes. Specifically, a picture on how gas flows through dark matter halos and onto galaxies to fuel star formation.
Lau, Marie Wingyee
core  

Post-Starburst Quasars

, 2009
We describe a comprehensive multi-wavelength and multi-faceted program to understand a class of quasars we call post-starburst quasars, which may represent an evolutionary phase in mutual galaxy/black hole evolution.
Rajib Ganguly, C. Paul, Gabriela Canalizo, Zhaohui Shang, R. Stoll, Sabrina Cales, Michael Brotherton, A. M. Diamond-Stanic   +7 more
core   +1 more source

Optimal distribution of VLBI transmitters in the Galileo space segment for frame ties. [PDF]

Earth Planets Space, 2023
Wolf H, Böhm J.
europepmc   +1 more source

The luminosity function of quasars and its evolution: A comparison of optically selected quasars and quasars found in radio catalogs [PDF]

, 1973
The luminosity function of quasars and its evolution are discussed, based on comparison of available data on optically selected quasars and quasars found in radio catalogs.
Petrosian, V.
core  

The soft X-ray properties of quasars in the sloan digital sky survey

, 2006
We use the ROSAT All-Sky Survey (RASS) to study the soft X-ray properties of a homogeneous sample of 46 420 quasars selected from the third data release of the Sloan Digital Sky Survey (SDSS).
Voges, W., Tremonti, C., White, Simon D. M., Voges, W, Shen, S., Mo, H., Mo, HJ, Kauffmann, G, Tremonti, C, Anderson, Scott F., Anderson, S., Shen, Shiyin, White, S., Mo, H. J., Kauffmann, Guinevere, White, SDM, Anderson, SF, Kauffmann, G., Shen, SY, Tremonti, Christy, Voges, Wolfgang   +20 more
core   +1 more source

The Detection Rate of Associated Mg ii Absorption Lines in Quasars Depends on Their Radio Emission

The Astrophysical Journal
In active galactic nuclei, jet-driven feedback plays a significant role in influencing the properties of gas within their host galaxy and the circumgalactic medium.
Zhi-Fu Chen, Luis C. Ho
doaj   +1 more source