arXiv subjects

Brian Punsly

Publications and source records attributed to Brian Punsly.

At least 19 recordsLinked to original sources

arXiv2026

Observations of a Possible Transient Magnetically Arrested Accretion State in a Nearby Quasar: OQ208

OQ208 is a nearby, partially obscured quasar (z=0.077) that is a young, bright, parsec scale radio source. We assemble archival and new high frequency VLBA and VLA observations and optical spectra to form a data-set spanning 39 years. Radio light curves covering 58 years were also compiled. We utilize new spectrophotmetry to calibrate previous spectroscopy using forbidden narrow lines that are expected to be stable on much longer time scales. VLBA and VLA observations of a light-year scale bright nuclear flare at 15.4~GHz and 22~GHz reveal a rise (fade) beginning in mid-1996 (early-2000). Quasi-contemporaneously, from 2/7/1997-6/3/2000, the H$\alpha$ broad line equivalent widths (EWs) and fluxes dropped dramatically. In the context of the tendency of radio loud quasars to have a depressed extreme ultraviolet (EUV) continuum (the main source of ionizing flux for H$\alpha$) relative to radio quiet quasars at matched UV luminosity (the EUV deficit of radio loud quasars), this may not be a coincidence. Analytic models previously developed to explain the relationship between jet power and the EUV deficit are consistent with (but not direct observational proof of) the small EWs being a consequence of transient magnetically arrested accretion states from $\sim1997-2001$. The 22 GHz VLBA nucleus gradually fades, in 2023 the flux density is $<5\%$ of its value in 2000. The environs of the nucleus also fade at 22 GHz, but in a time delayed fashion.

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arXiv2026

Investigating the origin of radio emission in candidate super-Eddington accreting black holes

Recent works show that the radio power of quasars accreting at very high rates can reach surprisingly high values. These studies suggest that this radio emission might originate from star formation, but lack of data leaves open the possibility that they could also contain a jetted active galactic nucleus (AGN). We investigate the origin of the radio emission of a sample of 18 super-Eddington candidates, over a wide range of redshifts. These sources are expected to have extreme radiative output per unit black hole mass, show high-velocity outflows and are therefore thought to be a prime mover of galactic evolution via radiative and mechanical feedback. We present new Karl G. Jansky Very Large Array (VLA) observations at L, C and X-band of these sources, which we combine with observations from the LOw-Frequency ARray (LOFAR) Two-metre Sky Survey (LoTSS) and the Very Large Array Sky Survey (VLASS). We also use optical and IR data to derive estimates of accretion and wind parameters, as well as star formation rates to compare with the ones derived from the radio emission. Based on the radio variability, luminosity, morphology, radio spectral properties, radio vs IR estimates of star formation rate and radio-to-mid IR flux ratio, we find that 7 of our 18 targets are likely to have their radio emission predominantly coming from SF, and 6 from a combination of SF and AGN-related mechanisms, while only three sources indicate a core or jetted AGN only origin for the detected radio emission. This is consistent with previous studies, and supports the prevalence of lower power radio structures associated with star-forming activity rather than relativistic jets in the high Eddington ratio regime. In the same sample, however, we find three sources for which the data suggest a concomitant presence of super-Eddington accretion and relativistic ejections.

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arXiv2024

First image of a jet launching from a black hole accretion system: Kinematics

Jets are endemic to both Galactic solar mass and extragalactic supermassive black holes. A recent 86 GHz image of M\,87 shows a jet emerging from the accretion ring around a black hole, providing the first direct observational constraint on the kinematics of the jet-launching region in any black hole jetted system. The very wide ($\sim280μ\rm{as}$), highly collimated, limb-brightened cylindrical jet base is not predicted in current numerical simulations. The emission was shown to be consistent with that of a thick-walled cylindrical source that apparently feeds the flow that produces the bright limbs of the outer jet at an axial distance downstream of $0.4 \,\rm{mas}<z<0.65\, \rm{mas}$. The analysis here applies the conservation laws of energy, angular momentum, and magnetic flux to the combined system of the outer jet, the cylindrical jet, and the launch region. It also uses the brightness asymmetries of the jet and counterjet to constrain the Doppler factor. The only global solutions have a source that is located $<34 μ\rm{as}$ from the event horizon. This includes the Event Horizon Telescope annulus of emission and the regions interior to this annulus. The axial jet begins as a magnetically dominated flow that spreads laterally from the launch radius ($<34 μ\rm{as}$). It becomes super-magnetosonic before it reaches the base of the cylindrical jet. The flow is ostensibly redirected and collimated by a cylindrical nozzle formed in a thick accretion disk. The flow emerges from the nozzle as a mildly relativistic ($0.3c<v<0.4c$) jet with a significant protonic kinetic energy flux.

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arXiv2023

The cylindrical jet base of M87 within 100$μ\rm{as}$ of the central engine

A recent article on high-resolution 86 GHz observations with the Global Millimeter VLBI Array, the phased Atacama Large Millimeter/submillimeter Array, and the Greenland Telescope describes the detection of a limb-brightened cylindrical jet, $25 μ\rm{as}< z< 100 μ\rm{as}$, where $z$ is the axial displacement from the supermassive black hole in the sky plane. It was shown to be much wider and much more collimated than 2D simulations of electromagnetic (Blandford-Znajek) jets from the event horizon predicted. This was an unanticipated discovery. The claimed detection of a jet connected to the accretion flow provides a direct observational constraint on the geometry and physics of the jet launching region for the first time in any black hole jetted system. This landmark detection warrants further analysis. This Letter focuses on the most rudimentary properties, the shape and size of the source of the detected jet emission, the determination of which is not trivial due to line-of-sight effects. Simple thick-walled cylindrical shell models for the source were analyzed to constrain the thickness of the jet wall. The analysis indicates a tubular jet source with a radius $R\approx 144 μ\rm{as}\approx 38M$ and that the tubular jet walls have a width $W \approx 36μ\rm{as} \approx 9.5 M$, where $M$ is the geometrized mass of the black hole (a volume comparable to that of the interior cavity). The observed cylindrical jet connects continuously to the highly limb-brightened jet (previously described as a thick-walled tubular jet) that extends to $z> 0.65$ mas, and the two are likely in fact the same outflow (i.e., from the same central engine).

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arXiv2023

HST-1 as a Window to the Energetics of the Jet Spine of M87

A new interpretation of the optical knot in the jet of M87, HST-1, is presented. High sensitivity 22 GHz Very Large Array images locate HST-1 to within 6 mas of the jet axis immediately upstream. 1.7 GHz Very Long Baseline Array images of a bright flare in 2005 indicates that the preponderance of emission in the early stages originates in an elongated region that is tilted $12.5^{\circ}$ from the jet axis. The superluminal motion, shape, location and the large jet-aligned optical/UV polarization suggest an identification with the putative relativistic spine of the jet. As such, energy flux estimates for HST-1, $\sim 870$ mas from the nucleus, published in 2006 indicate that the central engine injected $Q_{\rm{spine}}\approx 2.5 \times 10^{41}\rm{ergs/s}$ into the base of the spine $\sim 200$ years earler. Furthermore, previous studies reveal a tubular protonic jet on sub-mas scales that envelopes a low luminosity core, presumably the faint spine base. It was estimated that the central engine injected $Q_{\rm{tubular\,jet}}\approx 6.1\times 10^{41}\rm{ergs/s}$ $\sim 1.5$ years earlier. If one component of the jet is inherently more powerful, a firm constraint on total jet power in the recent past exists. If the emitted jet is inherently dominated by the spine (tubular jet) then the total bilaterally symmetric jet power emitted from the central engine was $<4Q_{\rm{spine}}\approx 1.0 \times 10^{42}\rm{ergs/s}$ ($< 4Q_{\rm{tubular\,jet}}\approx 2.4\times 10^{42}\rm{ergs/s}$) $\sim 200$ ($\sim 1.5$) years earlier. Assuming a nearly constant central engine injected jet power for $\sim 200$ years indicates a total jet power of $\lesssim 2\times 10^{42}$ ergs/s in epochs of modern observation or $\lesssim 3.5\%$ jet production efficiency for an accretion rate of 0.001$M_{\odot}$/yr.

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arXiv2022

The Details of Limb Brightening Reveal the Structure of the Base of the Jet in M\,87 for the First Time

It has become commonplace is astronomy to describe the transverse coarse structure of jets in loosely defined terms such as "sheath" and "spine" based on discussions of parsec scale properties. But, the applicability, dimension and prominence of these features on sub-lt-yr scales has previously been unconstrained by observation. The first direct evidence of jet structure near the source in M\,87 is extreme limb brightening (a double-rail morphology), 0.3 - 0.6 mas from the source, that is prominent in observations with high resolution and sensitivity. Intensity cross-cuts of these images provide three strong, interdependent constraints on the geometry responsible for the double-rail morphology: the rail to rail separation, the peak to trough intensity ratio and the rail widths. Analyzing these constraints indicates that half or more of the jet volume resides in a thick-walled, tubular, mildly relativistic, protonic jet only $\sim 0.25$ lt-yr (or $\sim 300$ M, where M is the central black hole mass in geometrized units) from the source. By contrast, the Event Horizon Telescope Collaboration interprets their observations with the aid of general relativistic magnetohydrodynamic simulations that produce an invisible (by construction) jet with a surrounding luminous, thin sheath. Yet, it is shown that synthetic images of simulated jets are center brightened 0.3 - 0.6 mas from the source. This serious disconnection with observation occurs in a region previously claimed in the literature to be well represented by the simulations. The limb brightening analysis motivates a discussion of possible simulation modifications to improve conformance with observations.

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arXiv2022

The Energetics of the Central Engine in the Powerful Quasar, 3C298

The compact steep spectrum radio source, 3C 298, (redshift of 1.44) has the largest 178 MHz luminosity in the 3CR (revised Third Cambridge Catalogue) catalog; its radio lobes are among the most luminous in the Universe. The plasma state of the radio lobes is modeled with the aid of interferometric radio observations (in particular, the new Low Frequency Array observation and archival MERLIN data) and archival single-station data. It is estimated that the long-term time-averaged jet power required to fill these lobes with leptonic plasma is $\overline{Q} \approx 1.28 \pm 0.51 \times 10^{47} \rm{erg}\,\rm{s}^{-1}$, rivaling the largest time averaged jet powers from any quasar. Supporting this notion of extraordinary jet power is a 0.5 keV -10 keV luminosity of $\approx 5.2 \times 10^{46} \rm{erg}\, \rm{s}^{-1}$, comparable to luminous blazars, yet there is no other indication of strong relativistic beaming. We combine two new high signal to noise optical spectroscopic observations from the Hobby-Eberly Telescope with archival Hubble Space Telescope, Two Micron Survey and Galaxy Evolutionary Explorer data to compute a bolometric luminosity from the accretion flow of $L_{\rm{bol}} \approx 1.55 \pm 0.15 \times 10^{47} \rm{erg} \,\rm{s}^{-1}$. The ratio, $\overline{Q}/L_{\rm{bol}}\approx 1$, is the approximate upper limit for quasars. Characteristic of a large $\overline{Q}/L_{\rm{bol}}$, we find an extreme ultraviolet (EUV) spectrum that is very steep (the "EUV deficit" of powerful radio quasars relative to radio quiet quasars) and this weak ionizing continuum is likely a contributing factor to the relatively small equivalent widths of the broad emission lines in this quasar.

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arXiv2021

Did the Event Horizon Telescope Detect the Base of the Sub-Milliarsecond Tubular Jet in M\,87?

A high sensitivity, 7mm Very Long Baseline Array image of M\,87 was previously analyzed in order to estimate the bulk flow jet velocity between 0.4 and 0.65 mas from the point of origin using the asymmetry between the well-characterized double-ridged counter-jet (unique to this image) and the double ridged jet. We use this same image to estimate the cross-sectional area of this tubular stream. The velocity, acceleration, cross-sectional area and flux density along this stream determines a unique, perfect magnetohydrodynamic jet solution that satisfies, conservation of energy, angular momentum and mass (a monotonic conversion of Poynting flux to kinetic energy flux along the jet). The solution is protonic and magnetically dominated. The bilateral jet transports $\approx 1.2\times10^{-4} M_{\odot}/\rm{yr}$ and $\approx 1.1\times10^{42}$ erg/sec, placing strong constraints on the central engine. A Keplerian disk source that also produces the Event Horizon Telescope (EHT) annulus of emission can supply the energy and mass if the vertical magnetic field at the equator is $\sim 1-3.5$ G (depending on location). A Parker spiral magnetic field, characteristic of a wind or jet, is consistent with the observed EHT polarization pattern. Even though there is no image of the jet connecting with the annulus, it is argued that these circumstances are not coincidental and the polarized portion of the EHT emission is mainly jet emission in the top layers of the disk that is diluted by emission from an underlying turbulent disk. This is a contributing factor to the relatively low polarization levels that were detected.

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arXiv2021

The Highly Self-Absorbed Blazar, PKS\,1351$-$018

PKS\,1351$-$018 at a redshift of $z=3.71$ is one of the most luminous, steady synchrotron sources with a luminosity $> 10^{47}$\,erg~s$^{-1}$. The synchrotron luminosity does not seem to vary by more than $\sim 25\%$ over 35 years. In order to appreciate this remarkable behavior, if it were at $z=0.5$, it would have a flux density at 15 GHz in a range of $110 - 137$\,Jy over 11 yrs. In spite of this steady behavior, two strong $γ$-ray flares $\lesssim 10^{49}$\,erg~s$^{-1}$ were detected in 2011 and 2016. There is blazar-like behavior coexisting with the steady behavior. This study is aimed at elucidating the dual nature of this source. We find that the radio source is extremely compact with a bright core and a steep spectrum secondary component, 12\,mas away, that appears to be constant in position and flux density in six epochs from 1995 to 2018. We estimate that a jet with a time averaged power of $(5.2 \pm 3.2) \times 10^{45}$\,erg~s$^{-1}$ terminates in this lobe that is advancing $\gtrsim 0.9 c$ at a deprojected distance of $1-3$\,kpc from the central engine. This is the rare case of a young ($\sim 6000$\,yr), very powerful radio source that is viewed a few degrees from the jet axis. We find evidence of a high velocity (4000\,km~s$^{-1}$), high ionization wind emanating form a luminous quasar. The young radio jet appears to experience modest bending as it navigates through the intense quasar environment.

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arXiv2021

The Bulk Flow Velocity and Acceleration of the Inner Jet in M\,87

A high sensitivity, 7mm Very Long Baseline Array image of M\,87 is analyzed in order to estimate the jet velocity within 0.65 mas of the point of origin. The image captured a high signal to noise, double-ridged, counter-jet extending $\sim 1$ mas from the nucleus. After defining conditions and requirements that justify approximate time averaged bilateral symmetry, a continuous set of Lorentz transformations are found that map the double-ridged counter-jet intensity profile into the double-ridged jet intensity profile. The mapping is realized by a uniformly accelerating flow with intrinsic velocity of $\sim 0.27$c at 0.4 mas (a de-projected distance of 0.38 lt-yrs) to $0.38$c at 0.65 mas (a de-projected distance of 0.61 lt-yrs) from the nucleus. Since the velocity field is derived from the global surface brightness profile and does not depend on the motion of enhanced features, it is most likely a bulk flow velocity as opposed to a pattern velocity. This interpretation is corroborated by the fact that the distribution of the apparent velocities of previously identified individual features (from the literature) within 0.65 mas of the nucleus are consistent with local hydrodynamic shocks being advected with the local bulk flow velocity. The bulk flow velocity of the visible inner jet is a constraint that can potentially break degeneracies between numerical simulations that are designed to replicate both the annulus that was imaged by the Event Horizon Telescope as well as the base of the inner jet.

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arXiv2021

Observing the Time Evolution of the Multi-Component Nucleus of 3C\,84

The advent of global mm-band Very Long Baseline Interferometry (VLBI) in recent years has finally revealed the morphology of the base of the two most prominent nearby, bright, extragalactic radio jets in M\,87 and 3C\,84. The images are quite surprising considering the predictions of jet theory and current numerical modeling. The jet bases are extremely wide compared to expectations and the nucleus of 3C\,84 is very complicated. It appears as a double in 86\,GHz observations with 50\,$μ$as resolution and a triple nucleus with 30\,$μ$as resolution with space-based VLBI by RadioAstron at 22\,GHz. What is even odder is that the double and triple are arranged along an east-west line that is approximately orthogonal to the north-south large scale jet on 150\,$μ$as $-$ 4\,mas scales. We explore the emergence of an (east-west) double nucleus in the lower resolution 43\,GHz Very Long Baseline Array (VLBA) imaging from August 2018 to April 2020. The double is marginally resolved. We exploit the east-west resolution associated with the longest baselines, $\sim 0.08$\,mas, to track a predominantly east-west separation speed of $\approx 0.086\pm 0.008$\,c. We estimate that the observed mildly relativistic speed persists over a de-projected distance of $\sim 1900-9800$ times the central, supermassive black hole, gravitational radius ($\sim 0.3-1.5$\,lt-yrs) from the point of origin.

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arXiv2020

The Extreme Red Excess in Blazar Ultraviolet Broad Emission Lines

We present a study of quasars with very redward asymmetric (RA) ultraviolet (UV) broad emission lines (BELs). An excess of redshifted emission has been previously shown to occur in the BELs of radio loud quasars and is most extreme in certain blazars. Paradoxically, blazars are objects that are characterized by a highly relativistic blue-shifted outflow towards Earth. We show that the red emitting gas resides in a very broad component (VBC) that is typical of Population B quasars that are defined by a wide H$β$ BEL profile. Empirically, we find that RA BEL blazars have both low Eddington rates ($\lesssim1\%$) and an inordinately large (order unity) ratio of long term time averaged jet power to accretion luminosity. The latter circumstance has been previously shown to be associated with a depressed extreme UV ionizing continuum. Both properties conspire to produce a low flux of ionizing photons, two orders of magnitude less than typical Population B quasars. We use CLOUDY models to demonstrate that a weak ionizing flux is required for gas near the central black hole to be optimally ionized to radiate BELs with high efficiency (most quasars over-ionize nearby gas, resulting in low radiative efficiency). The large gravitational redshift and transverse Doppler shift results in a VBC that is redshifted by $\sim 2000 -5000$~km~s$^{-1}$ with a correspondingly large line width. The RA BELs result from an enhanced efficiency (relative to typical Population B quasars) to produce a luminous, redshifted VBC near the central black hole.

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arXiv2020

The Energetics of Launching the Most Powerful Jets in Quasars: A Study of 3C82

3C 82 at a redshift of 2.87 is the most distant 3C (Third Cambridge Catalogue) quasar. Thus, it is a strong candidate to have the most luminous radio lobes in the Universe. 3C 82 belongs to the class of compact steep spectrum radio sources. We use single dish and interferometric radio observations in order to model the plasma state of these powerful radio lobes. It is estimated that the long-term time-averaged jet power required to fill these lobes with leptonic plasma is $\overline{Q} \approx 2.66 \pm 1.33 \times 10^{47} \rm{ergs/sec}$, among the largest time averaged jet powers from a quasar. Positing protonic lobes is not tenable since they would require two orders of magnitude more mass transport to the lobes than was accreted to the central black hole during their formation. The first high signal to noise optical spectroscopic observation obtained of this object indicates that there is a powerful high ionization broad line wind with a kinetic power $\sim 10^{45} \rm{ergs/sec}$ and a velocity $\sim 0.01$c. We also estimate from the broad lines in 2018 and the UV continuum in three epochs spread out over three decades that the accretion flow bolometric luminosity is $L_{\rm{bol}} \approx 3.2-5.8 \times 10^{46} \rm{ergs/sec}$. The ratio of $\overline{Q}/L_{\rm{bol}}\approx 6.91 \pm 3.41$, is perhaps the largest of any known quasar. Extremely powerful jets tend to strongly suppress powerful winds of ionized baryonic matter. Consequently, 3C 82 provides a unique laboratory for studying the dynamical limits of the central engine of outflow initiation in quasars.

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arXiv2020

Estimating the Jet Power of Mrk\,231 During the 2017-2018 Flare

Long-term 17.6~GHz radio monitoring of the broad absorption line quasar, Mrk\,231, detected a strong flare in late 2017. This triggered four epochs of Very Long Baseline Array (VLBA) observations from 8.4~GHz to 43~GHz over a 10-week period as well as an X-ray observation with NuSTAR. This was the third campaign of VLBA monitoring that we have obtained. The 43~GHz VLBA was degraded in all epochs with only 7 of 10 antennas available in three epochs and 8 in the first epoch. However, useful results were obtained due to a fortuitous capturing of a complete short 100~mJy flare at 17.6~GHz: growth and decay. This provided useful constraints on the physical model of the ejected plasma that were not available in previous campaigns. We consider four classes of models, discrete ejections (both protonic and positronic) and jetted (protonic and positronic). The most viable model is a "dissipative bright knot" in a faint background leptonic jet with an energy flux $\sim10^{43}$ ergs/sec. Inverse Compton scattering calculations (based on these models) in the ambient quasar photon field explains the lack of a detectable increase in X-ray luminosity measured by NuSTAR. We show that the core (the bright knot) moves towards a nearby secondary at $\approx 0.97$c. The background jet is much fainter. Evidently, the high frequency VLBA core does not represent the point of origin of blazar jets, in general, and optical depth "core shift" estimates of jet points of origin can be misleading.

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arXiv2019

Constraints on Black Hole Jet Models Used As Diagnostic Tools of Event Horizon Telescope Observations of M87

Jet models of Event Horizon Telescope (EHT) data should also conform to the observed jet profiles just downstream. This study evaluates conformance of models of black hole jets to images of the innermost jet of M87. This is a basic test that should be passed before using them to perform a physical interpretation of EHT data. Recent 86 GHz Very Long Baseline Interferometry observations of M87 have revealed the morphology and size of the jet near its source ($<65$\,M, or 0.06 lt-yrs after correcting for line of sight to the jet, where $M$ is the black hole mass in geometrized units) for the first time. Current transverse resolution indicates that this region is dominated by flux emanating from the edge of the jet. The observed inner jet profiles are compared to all existing published synthetic radio images constructed from "state of the art" 3-D numerical simulations of the black hole accretion system in M87. Despite efforts to produce the characteristic wide, edge dominated jet, these models are too narrow (by a factor of $\sim2$) in the region 0.06 - 0.32 lt-yrs from the source, even though the jets (spine and/or sheath) in the image plane might appear conformant farther downstream. Furthermore, the synthetic radio images are not edge dominated 0.06 - 0.32 lt-yrs from the source, but spine dominated. Analyses that implement these models as physical diagnostics of EHT visibility amplitudes are therefore suspect. Thus, these inner jet characteristics are important considerations before applying simulations to the EHT data.

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arXiv2019

Discrete and Continuous Ejection Models of the Radio Source Associated with GW170817

The gravity wave source, GW170817, and associated gamma ray burst (GRB), GRB 170817A, produced radio emission that was detected in multiple epochs of Very Long Baseline Interferometry (VLBI) and with broadband radio photometry. Three unique pieces of observational evidence were determined: a discrete radio emitting region that moves with an apparent velocity of $\approx 4$c, the discrete region includes all of the radio flux, and there is likely a synchrotron self absorption (SSA) spectral turnover on day $\sim 110$ and day $\sim 160$ after ejection. This unprecedented wealth of data for a GRB provides a unique opportunity to understand the radio emitting plasma that was ejected by the putative merger event. The velocity can constrain the kinematics and the SSA turnover has been used to constrain the size to much smaller than can be done with an unresolved VLBI image, allowing one to estimate the associated plasmoid size directly from the data and improve estimates of the energetics. Models of the radio emission for both a turbulent, protonic, discrete ballistic ejection and a high dissipation region within an otherwise invisible Poynting flux dominated positron-electron jet are considered. On days $\sim 110$ and $\sim 160$ post-merger, for the range of models presented, the jet power is $2\times 10^{39} - 8\times 10^{40} \rm{ergs/s}$ and the ballistic plasmoid kinetic energy is $3\times 10^{45} - 1.5\times 10^{47} \rm{ergs}$. Even though only valid after day 110, this independent analysis augments traditional GRB light curve studies, providing additional constraints on the merger event.

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arXiv2018

The Powerful Jet and Gamma-Ray Flare of the Quasar PKS 0438$-$436

PKS 0438$-$436 at a redshift of $z=2.856$ has been previously recognized as possessing perhaps the most luminous known synchrotron jet. Little is known about this source since the maximum elevation above the horizon is low for the Very Large Array (VLA). We present the first VLA radio image that detects the radio lobes. We use both the 151 MHz luminosity, as a surrogate for the isotropic radio lobe luminosity, and the lobe flux density from the radio image to estimate a long term, time averaged, jet power, $\overline{Q} =1.5\pm 0.7 \times 10^{47} \rm{ergs~s^{-1}}$. We analyze two deep optical spectra with strong broad emission lines and estimate the thermal bolometric luminosity of the accretion flow, $L_{\rm{bol}} = 6.7 \pm 3.0 \times 10^{46} \rm{ergs~s^{-1}}$. The ratio, $\overline{Q}/L_{\rm{bol}} = 3.3 \pm 2.6 $, is at the limit of this empirical metric of jet dominance seen in radio loud quasars and this is the most luminous accretion flow to have this limiting behavior. Despite being a very luminous blazar, it previously had no $γ$-ray detections (EGRET, AGILE or FERMI) until December 11 - 13 2016 (54 hours) when FERMI detected a flare that we analyze here. The isotropic apparent luminosity from 100 MeV - 100 GeV rivals the most luminous detected blazar flares (averaged over 18 hours), $\sim 5-6 \times 10^{49} \rm{ergs~s^{-1}}$. The $γ$-ray luminosity varies over time by two orders of magnitude, highlighting the extreme role of Doppler abberation and geometric alignment in producing the inverse Compton emission.

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arXiv2018

Revealing the Broad Line Region of NGC 1275: The Relationship to Jet Power

NGC 1275 is one of the most conspicuous active galactic nuclei (AGN) in the local Universe. The radio jet currently emits a flux density of $\sim 10$ Jy at $\sim 1$ mm wavelengths, down from the historic high of $\sim 65$ Jy in 1980. Yet, the nature of the AGN in NGC 1275 is still controversial. It has been debated whether this is a broad emission line (BEL) Seyfert galaxy, an obscured Seyfert galaxy, a narrow line radio galaxy or a BL-Lac object. We clearly demonstrate a persistent H$β$ BEL over the last 35 years with a full width half maximum (FWHM) of 4150 - 6000 km/s. We also find a prominent P$α$ BEL (FWHM $\approx 4770 $ km/s) and a weak CIV BEL (FWHM $\approx 4000 $ km/s), H$β$/CIV $\approx 2$. A far UV HST observation during suppressed jet activity reveals a low luminosity continuum. The H$β$ BEL luminosity is typical of broad line Seyfert galaxies with similar far UV luminosity. X-ray observations indicate a softer ionizing continuum than expected for a broad line Seyfert galaxy with similar far UV luminosity. This is opposite of the expectation of advection dominated accretion. The AGN continuum appears to be thermal emission from a low luminosity, optically thick, accretion flow with a low Eddington ratio, $\sim 0.0001$. The soft, weak ionizing continuum is consistent with the relatively weak CIV BEL. Evidence that the BEL luminosity is correlated with the jet mm wave luminosity is presented. Apparently, the accretion rate regulates jet power.

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