Zobrazeno 1 - 10
of 22
pro vyhledávání: '"Meredith Powell"'
Autor:
Nico Cappelluti, Adi Foord, Stefano Marchesi, Fabio Pacucci, Angelo Ricarte, Melanie Habouzit, Fabio Vito, Meredith Powell, Michael Koss, Richard Mushotzky
Publikováno v:
Universe, Vol 10, Iss 7, p 276 (2024)
The nature and origin of supermassive black holes (SMBHs) remain an open matter of debate within the scientific community. While various theoretical scenarios have been proposed, each with specific observational signatures, the lack of sufficiently s
Externí odkaz:
https://doaj.org/article/be8323b32b5d47d082ccc7ac96a7c492
Autor:
Stephanie LaMassa, Alessandro Peca, C. Megan Urry, Eilat Glikman, Tonima Tasnim Ananna, Connor Auge, Francesca Civano, Aritra Ghosh, Allison Kirkpatrick, Michael J. Koss, Meredith Powell, Mara Salvato, Benny Trakhtenbrot
Publikováno v:
The Astrophysical Journal, Vol 974, Iss 2, p 235 (2024)
We present the third catalog release of the wide-area (31.3 deg ^2 ) Stripe 82 X-ray survey. This catalog combines previously published X-ray source properties with multiwavelength counterparts and photometric redshifts, presents 343 new spectroscopi
Externí odkaz:
https://doaj.org/article/03f6b15bba1e449f8da5ed92e49b2a41
Autor:
Connor Auge, David Sanders, Ezequiel Treister, C. Megan Urry, Allison Kirkpatrick, Nico Cappelluti, Tonima Tasnim Ananna, Médéric Boquien, Mislav Baloković, Francesca Civano, Brandon Coleman, Aritra Ghosh, Jeyhan Kartaltepe, Michael Koss, Stephanie LaMassa, Stefano Marchesi, Alessandro, Peca, Meredith Powell, Benny Trakhtenbrot, Tracey Jane Turner
Publikováno v:
The Astrophysical Journal, Vol 957, Iss 1, p 19 (2023)
Spectral energy distributions (SEDs) from X-ray to far-infrared (FIR) wavelengths are presented for a sample of 1246 X-ray-luminous active galactic nuclei (AGNs; L _0.5–10 keV > 10 ^43 erg s ^−1 ), with z _spec < 1.2, selected from Stripe 82X, CO
Externí odkaz:
https://doaj.org/article/8916ce2d60bd448db5b20b4c65e60405
Autor:
Alessandro Peca, Nico Cappelluti, C. Megan Urry, Stephanie LaMassa, Stefano Marchesi, Tonima Tasnim Ananna, Mislav Baloković, David Sanders, Connor Auge, Ezequiel Treister, Meredith Powell, Tracey Jane Turner, Allison Kirkpatrick, Chuan Tian
Publikováno v:
The Astrophysical Journal, Vol 943, Iss 2, p 162 (2023)
We present X-ray spectral analysis of XMM-Newton and Chandra observations in the 31.3 deg ^2 Stripe-82X (S82X) field. Of the 6181 unique X-ray sources in this field, we analyze a sample of 2937 candidate active galactic nuclei (AGNs) with solid redsh
Externí odkaz:
https://doaj.org/article/70c814fbbb1e4580b882990776f68cff
Autor:
Ryan W. Pfeifle, Claudio Ricci, Peter G. Boorman, Marko Stalevski, Daniel Asmus, Benny Trakhtenbrot, Michael J. Koss, Daniel Stern, Federica Ricci, Shobita Satyapal, Kohei Ichikawa, David J. Rosario, Turgay Caglar, Ezequiel Treister, Meredith Powell, Kyuseok Oh, C. Megan Urry, Fiona Harrison
Publikováno v:
The Astrophysical Journal Supplement Series, Vol 261, Iss 1, p 3 (2022)
In this study, we use the Swift/BAT AGN sample, which has received extensive multiwavelength follow-up analysis as a result of the BAT AGN Spectroscopic Survey, to develop a diagnostic for nuclear obscuration by examining the relationship between the
Externí odkaz:
https://doaj.org/article/61b4e5acc458424e9664b2be6929771b
Autor:
Eve Purdy, Gillian Forster, Hayley Manlove, Laura McDonough, Meredith Powell, Krista Wood, Louise Rang, Damon Dagnone, Rob Brison, Doug Henry, Stuart L. Douglas
Publikováno v:
Canadian Journal of Emergency Medicine. 24:585-598
Professional culture is a powerful influence in emergency departments, but incompletely understood. Disasters magnify cultural realities, and as such the COVID-19 pandemic offered a unique opportunity to better understand emergency medicine (EM) valu
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e1a864d78ea45d2518d1ffdfa6bb672d
https://doi.org/10.1007/s43678-022-00383-0
https://doi.org/10.1007/s43678-022-00383-0
Autor:
Alessandro Peca, Nico Cappelluti, C. Megan Urry, Stephanie LaMassa, Stefano Marchesi, Tonima Tasnim Ananna, Mislav Baloković, David Sanders, Connor Auge, Ezequiel Treister, Meredith Powell, Tracey Jane Turner, Allison Kirkpatrick, Chuan Tian
We present X-ray spectral analysis of XMM and Chandra observations in the 31.3 deg$^2$ Stripe-82X (S82X) field. Of the 6181 X-ray sources in this field, we analyze a sample of 2937 active galactic nuclei (AGN) with solid redshifts and sufficient coun
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::6efd6a5d4f2c94f12635f07467d6b5db
http://arxiv.org/abs/2210.08030
http://arxiv.org/abs/2210.08030
Autor:
Krista Lynne Smith, C. Megan Urry, Kevin Schawinski, Kohei Ichikawa, Fiona A. Harrison, Laura Blecha, George C. Privon, Ezequiel Treister, T. Taro Shimizu, D. Kakkad, Claudio Ricci, Daniel Stern, Richard Mushotzky, Michael Koss, Benny Trakhtenbrot, T. Liu, Meredith Powell, Kyuseok Oh
Theory predicts that a supermassive black hole binary (SMBHB) could be observed as a luminous active galactic nucleus (AGN) that periodically varies on the order of its orbital timescale. In X-rays, periodic variations could be caused by mechanisms i
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e4d21346f5b3f29a1351c1ce33ef91be
https://resolver.caltech.edu/CaltechAUTHORS:20200624-104212632
https://resolver.caltech.edu/CaltechAUTHORS:20200624-104212632
Autor:
Benny Trakhtenbrot, Fiona A. Harrison, O. Ivy Wong, J. Mejia-Restrepo, Franz E. Bauer, Junhyun Baek, Krista Lynne Smith, Claudio Ricci, C. Meg Urry, Richard F. Mushotzky, Stuart N. Vogel, Meredith Powell, Federica Ricci, Kyuseok Oh, Aeree Chung, Daniel Stern, Michael Koss
We have conducted 22 GHz radio imaging at 1" resolution of 100 low-redshift AGN selected at 14-195 keV by the Swift-BAT. We find a radio core detection fraction of 96%, much higher than lower-frequency radio surveys. Of the 96 radio-detected AGN, 55
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::90f93df6ae3760ce6b3c45f822607aff
Autor:
Tonima Tasnim Ananna, K. E. Kollmann, Stephanie M. LaMassa, Nico Cappelluti, C. M. Urry, Jeremiah Johnson, Meredith Powell
The clustering of active galactic nuclei (AGN) sheds light on their typical large (Mpc-scale) environments, which can constrain the growth and evolution of supermassive black holes. Here we measure the clustering of luminous X-ray-selected AGN in the
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::1b8eb7e5d918b69f899e9587984e17d1