5 research outputs found
A Candidate Dual Active Galactic Nucleus At Z=1.175
The X-ray source CXOXBJ142607.6+353351 (CXOJ1426+35), which was identified in a 172 ks Chandra image in the Bootes field, shows double-peaked rest-frame optical/UV emission lines, separated by 0.''69 (5.5 kpc) in the spatial dimension and by 690 km s(-1) in the velocity dimension. The high excitation lines and emission line ratios indicate both systems are ionized by an active galactic nucleus (AGN) continuum, and the double-peaked profile resembles that of candidate dual AGNs. At a redshift of z = 1.175, this source is the highest redshift candidate dual AGN yet identified. However, many sources have similar emission line profiles for which other interpretations are favored. We have analyzed the substantial archival data available in this field as well as acquired near-infrared (NIR) adaptive optics (AO) imaging and NIR slit spectroscopy. The X-ray spectrum is hard, implying a column density of several 10(23) cm(-2). Though heavily obscured, the source is also one of the brightest in the field, with an absorption-corrected 2-10 keV luminosity of similar to 10(45) erg s(-1). Outflows driven by an accretion disk may produce the double-peaked lines if the central engine accretes near the Eddington limit. However, we may be seeing the narrow line regions of two AGNs following a galactic merger. While the AO image reveals only a single source, a second AGN would easily be obscured by the significant extinction inferred from the X-ray data. Understanding the physical processes producing the complex emission line profiles seen in CXOJ1426+35 and related sources is important for interpreting the growing population of dual AGN candidates.National Science Foundation AST-0708490Strategic University Research Partnership ProgramNational Aeronautics and Space AdministrationW. M. Keck FoundationSmithsonian Astrophysical Observatory SV4-74018, A31Astronom
A Candidate Dual AGN at z=1.175
The X-ray source CXOXBJ142607.6+353351 (CXOJ1426+35), which was identified in
a 172 ks Chandra image in the Bootes field, shows double-peaked rest-frame
optical/UV emission lines, separated by 0.69" (5.5 kpc) in the spatial
dimension and by 690 km s^-1 in the velocity dimension. The high excitation
lines and emission line ratios indicate both systems are ionized by an AGN
continuum, and the double-peaked profile resembles that of candidate dual AGN.
At a redshift of z=1.175, this source is the highest redshift candidate dual
AGN yet identified. However, many sources have similar emission line profiles
for which other interpretations are favored. We have analyzed the substantial
archival data available in this field, as well as acquired near-infrared (NIR)
adaptive optics (AO) imaging and NIR slit spectroscopy. The X-ray spectrum is
hard, implying a column density of several 10^23 cm^-2. Though heavily
obscured, the source is also one of the brightest in the field, with an
absorption-corrected 2-10 keV luminosity of ~10^45 erg s^-1. Outflows driven by
an accretion disk may produce the double-peaked lines if the central engine
accretes near the Eddington limit. However, we may be seeing the narrow line
regions of two AGN following a galactic merger. While the AO image reveals only
a single source, a second AGN would easily be obscured by the significant
extinction inferred from the X-ray data. Understanding the physical processes
producing the complex emission line profiles seen in CXOJ1426+35 and related
sources is important for interpreting the growing population of dual AGN
candidates.Comment: 18 pages and 9 figures. Accepted for publication in The Astrophysical
Journa
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Consistency Among Social Groups in Judging Emotions Across Time
We measured judgments about emotions across time. In Study 1 (N = 254) and Study 2 (N = 162), LGBTQ-Latinx, straight-Latinx, LGBTQ-White, and straight-White emerging adults rated how they would feel if a perpetrator acted positively (P) or negatively (N) toward them in single, isolated events. In Study 2, participants also responded to a new emotions across time task where they judged how they would feel interacting with a hypothetical perpetrator across three timepoints: (1) an initial past event, (2) a recent past event, and (3) an uncertain future-oriented event (e.g., seeing the perpetrator again). Participants further predicted their thoughts and decisions in the uncertain future-oriented event. The past emotional events appeared in various sequences (PP, NN, NP, PN). Results indicated that participants judged events as emotionally unambiguous when occurring first in a sequence or in isolation (positive events feel better than negative events). In contrast, initial events shaped emotional reactions to subsequent events: Participants responded more intensely to episodes that were preceded by events of the same valence. In addition to this augmenting effect, initial negative events were especially sticky: Participants rated a positive event following a negative event as feeling less good than when a positive event appeared first or in isolation, but they judged negative events to feel equivalently bad regardless of order. When evaluating future-oriented affective states, participants drew from the prior experiences and prioritized the recent past (more positive emotions, thoughts, and decisions for PP > NP > PN > NN). Effects replicated across all social groups. (PsycInfo Database Record (c) 2022 APA, all rights reserved)