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Abstract We present analysis of one of the most extreme quasar outflows found to date in our survey of extremely high-velocity outflows (EHVOs). J164653.72+243942.2 (z_em ∼ 3.04) shows variable Civλλ1548,1551 absorption at speeds larger than 0.1c, accompanied by Siiv, Nv,and Lyα, and disappearing absorption at lower speeds. We perform absorption measurements using the apparent optical depth method and SimBAL. We find the absorption to be very broad (Δv ∼  35,100 km s⁻¹in the first epoch and 13,000 km s⁻¹in the second one) and fast (v_max ∼  –50,200 km s⁻¹and −49,000 km s⁻¹, respectively). We measure large column densities ( $\log N_{\mathrm{H}}>$21.6 (cm⁻²)) and are able to place distance estimates for the EHVO (5 ≲ R ≲ 28 pc) and the lower-velocity outflow (7 ≲ R ≲ 540 pc). We estimate a mass outflow rate for the EHVO to be ${\dot{M}}_{\mathrm{out}}\sim 50–290M_{\odot }{\mathrm{yr}}^{-1}$and a kinetic luminosity of $\log L_{\mathrm{KE}}\sim 46.5–47.2\left(\mathrm{erg}{\mathrm{s}}^{-1}\right)$in both epochs. The lower-velocity component has a mass outflow rate ${\dot{M}}_{\mathrm{out}}\sim 10–790M_{\odot }{\mathrm{yr}}^{-1}$and a kinetic luminosity of $\log L_{\mathrm{KE}}\sim 45.3–47.2\left(\mathrm{erg}{\mathrm{s}}^{-1}\right)$. We find that J164653.72+243942.2 is not an outlier among EHVO quasars in regard to its physical properties. While its column density is lower than typical BAL values, its higher outflow velocities drive most of the mass outflow rate and kinetic luminosity. These results emphasize the crucial role of EHVOs in powering quasar feedback, and failing to account for these outflows likely leads to underestimating the feedback impact on galaxies. 

We report the discovery of an extremely high-velocity outflow (EHVO) in the most luminous QSO (L_Bol∼ 2.29 × 10⁴⁸erg/s), named SMSS J2157-3602, atz = 4.692. Combined XSHOOTER and NIRES observations reveal that the EHVO reaches a maximum velocity ofv_max ∼ 0.13cand persists over rest-frame timescales of a few months up to one year. SMSS J2157-3602 also exhibits one of the highest balnicity index values discovered for an EHVO so far. In addition, the blueshifted CIV emission traces a high-velocity (v_CIV⁵⁰∼ 4660 km/s) outflow from the broad-line region (BLR). Thanks to an XMM-Newton observation, we were also able to reveal the X-ray weak nature of this QSO, which likely prevents the overionization of the innermost disk atmosphere and facilitates the efficient launch of the detected EHVO and BLR winds. The extraordinary luminosity of SMSS J2157-3602 and the extreme velocity of the EHVO make it a unique laboratory for testing active galactic nucleus (AGN) driven feedback under extreme conditions. Current uncertainties on the outflow’s location and column density strengthen the case for a dedicated follow-up, which will be essential to assess the full feedback potential of this remarkable quasar. 

Abstract Multiyear observations from the Sloan Digital Sky Survey (SDSS) Reverberation Mapping ​(RM) project have significantly increased the number of quasars with reliable RM lag measurements. We statistically analyze target properties, light-curve characteristics, and survey design choices to identify factors crucial for successful and efficient RM surveys. Analyzing 172 high-confidence (“gold”) lag measurements from SDSS-RM for the Hβ, Mgii, and Civemission lines, we find that the Durbin–Watson statistic (a statistical test for residual correlation) is the most significant predictor of light curves suitable for lag detection. The variability signal-to-noise ratio and emission-line placement on the detector also correlate with successful lag measurements. We further investigate the impact of the observing cadence on the survey design by analyzing the effect of reducing observations in the first year of SDSS-RM. Our results demonstrate that a modest reduction in the observing cadence to ∼1.5 weeks between observations can retain approximately 90% of the lag measurements compared to twice-weekly observations in the initial year. Provided similar and uniform sampling in subsequent years, this adjustment has a minimal effect on the overall recovery of lags across all emission lines. These results provide valuable inputs for optimizing future RM surveys. 

Abstract Over three decades of reverberation mapping (RM) studies on local broad-line active galactic nuclei (AGNs) have measured reliable black hole (BH) masses for >100 AGNs. These RM measurements reveal a significant correlation between the Balmer broad-line region (BLR) size and AGN optical luminosity (theR–Lrelation). Recent RM studies for AGN samples with more diverse BH parameters (e.g., mass and Eddington ratio) reveal a substantial intrinsic dispersion around the averageR–Lrelation, suggesting that variations in the broadband spectrum, driven by accretion parameters and other factors such as the cloud distribution and inclination, significantly influence the measuredR–Lrelation. Here we perform a detailed photoionization investigation of expected broad-line properties as functions of accretion parameters using AGN continuum models fromqsosed. We compare theoretical predictions with observations of a sample of 67z ≲ 0.5 reverberation-mapped AGNs with rest-frame optical and UV spectra in the moderate-accretion regime (Eddington ratioλ_Edd ≡ L/L_Edd < 0.5). The UV/optical line strengths and their dependences on accretion parameters are reasonably well reproduced by the locally optimally emitting cloud photoionization models. We provide quantitative recipes using optical/UV line flux ratios to infer the unobservable ionizing continuum. Additionally, photoionization models with universal values of ionization parameter ( $\log U_{\mathrm{H}}=-2$) and hydrogen density ( $\log n\left(\mathrm{H}\right)=12$) can qualitatively reproduce the observed globalR–Lrelation for the current RM AGN sample. However, such models fail to reproduce the observed decrease in BLR size with increasingL/L_Eddat fixed optical luminosity, implying that gas density or BLR structure may systematically change with accretion rate. 

Abstract Fluorescent probes are an indispensable tool in the realm of bioimaging technologies, providing valuable insights into the assessment of biomaterial integrity and structural properties. However, incorporating fluorophores into scaffolds made from melt electrowriting (MEW) poses a challenge due to the sustained, elevated temperatures that this processing technique requires. In this context, [n]cycloparaphenylenes ([n]CPPs) serve as excellent fluorophores for MEW processing with the additional benefit of customizable emissions profiles with the same excitation wavelength. Three fluorescent blends are used with distinct [n]CPPs with emission wavelengths of either 466, 494, or 533 nm, identifying 0.01 wt% as the preferred concentration. It is discovered that [n]CPPs disperse well within poly(ε‐caprolactone) (PCL) and maintain their fluorescence even after a week of continuous heating at 80 °C. The [n]CPP‐PCL blends show no cytotoxicity and support counterstaining with commonly used DAPI (Ex/Em: 359 nm/457 nm), rhodamine‐ (Ex/Em: 542/565 nm), and fluorescein‐tagged (Ex/Em: 490/515 nm) phalloidin stains. Using different color [n]CPP‐PCL blends, different MEW fibers are sequentially deposited into a semi‐woven scaffold and onto a solution electrospun membrane composed of [8]CPP‐PCL as a contrasting substrate for the [10]CPP‐PCL MEW fibers. In general, [n]CPPs are potent fluorophores for MEW, providing new imaging options for this technology. 

ABSTRACT We found a broad absorption line (BAL) outflow in the VLT/UVES spectrum of the quasar SDSS J235702.54−004824.0, in which we identified four subcomponents. We measured the column densities of the ions in one of the subcomponents (v = −1600 km s−1), which include O i and Fe ii. We found the kinetic luminosity of this component to be at most $$\sim 2.4{{\ \rm per\ cent}}$$ of the quasar’s Eddington luminosity. This is near the amount required to contribute to active galactic nucleus feedback. We also examined the time variability of a C iv mini-BAL found at v = −8700 km s−1, which shows a shallower and narrower absorption feature attached to it in previous SDSS observations from 2000 to 2001, but not in the spectra from 2005 and onwards. 

Abstract We measure the correlation between black hole massM_BHand host stellar massM_*for a sample of 38 broad-line quasars at 0.2 ≲z≲ 0.8 (median redshiftz_med= 0.5). The black hole masses are derived from a dedicated reverberation mapping program for distant quasars, and the stellar masses are derived from two-band optical+IR Hubble Space Telescope imaging. Most of these quasars are well centered within ≲1 kpc from the host galaxy centroid, with only a few cases in merging/disturbed systems showing larger spatial offsets. Our sample spans two orders of magnitude in stellar mass (∼10⁹–10¹¹M_⊙) and black hole mass (∼10⁷–10⁹M_⊙) and reveals a significant correlation between the two quantities. We find a best-fit intrinsic (i.e., selection effects corrected)M_BH–M_*,hostrelation of $\log \left(M_{\mathrm{BH}}/M_{\odot }\right)={7.01}_{-0.33}^{+0.23}+{1.74}_{-0.64}^{+0.64}\log \left(M_{*,\mathrm{host}}/{10}^{10}{M}_{\odot }\right)$, with an intrinsic scatter of ${0.47}_{-0.17}^{+0.24}$dex. Decomposing our quasar hosts into bulges and disks, there is a similarM_BH–M_*,bulgerelation with slightly larger scatter, likely caused by systematic uncertainties in the bulge–disk decomposition. TheM_BH–M_*,hostrelation atz_med= 0.5 is similar to that in local quiescent galaxies, with negligible evolution over the redshift range probed by our sample. With direct black hole masses from reverberation mapping and the large dynamical range of the sample, selection biases do not appear to affect our conclusions significantly. Our results, along with other samples in the literature, suggest that the locally measured black hole mass–host stellar mass relation is already in place atz∼ 1. 

Abstract We analyze Very Large Telescope/UVES observations of the quasar SDSS J024221.87+004912.6. We identify four absorption outflow systems: a C iv broad absorption line (BAL) at v ≈ −18,000 km s −1 and three narrower low-ionization systems with centroid velocities ranging from –1200 to –3500 km s −1 . These outflows show similar physical attributes to the [O iii ] outflows studied by Liu et al. (2013). We find that two of the systems are energetic enough to contribute to active galactic nucleus feedback, with one system reaching above 5% of the quasar’s Eddington luminosity. We also find that this system is at a distance of 67 kpc away from the quasar, the farthest detected mini-BAL absorption outflow from its central source to date. In addition, we examine the time-variability of the BAL and find that its velocity monotonically increases, while the trough itself becomes shallower over time. 

Abstract We present the results of an investigation of a highly variable Civbroad absorption line (BAL) feature in spectra of the quasar SBS 1408+544 (z= 2.337) that shows a significant shift in velocity over time. This source was observed as a part of the Sloan Digital Sky Survey (SDSS) Reverberation Mapping project and the SDSS-V Black Hole Mapper Reverberation Mapping project, and has been included in two previous studies, both of which identified significant variability in a high-velocity CivBAL on timescales of just a few days in the quasar rest frame. Using ∼130 spectra acquired over 8 yr of spectroscopic monitoring with SDSS, we have determined that this BAL is not only varying in strength, but is also systematically shifting to higher velocities. Using cross-correlation methods, we measure the velocity shifts (and corresponding acceleration) of the BAL over a wide range of timescales, measuring an overall velocity shift of $\mathrm{\Delta }v=-{683}_{-84}^{+89}$km s⁻¹over the 8 yr monitoring period. This corresponds to an average rest-frame acceleration ofa= 1.04 ${}_{-0.13}^{+0.14}$cm s⁻², though the magnitude of the acceleration on shorter timescales is not constant throughout. We place our measurements in the context of BAL-acceleration models and examine various possible causes of the observed velocity shift.