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Full-Text Articles in Physical Sciences and Mathematics
The Puzzling Case Of The Radio-Loud Qso 3c 186: A Gravitational Wave Recoiling Black Hole In A Young Radio Source?, Marco Chiaberge, Eric S. Perlman
The Puzzling Case Of The Radio-Loud Qso 3c 186: A Gravitational Wave Recoiling Black Hole In A Young Radio Source?, Marco Chiaberge, Eric S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
Context. Radio-loud active galactic nuclei with powerful relativistic jets are thought to be associated with rapidly spinning black holes (BHs). BH spin-up may result from a number of processes, including accretion of matter onto the BH itself, and catastrophic events such as BH-BH mergers. Aims. We study the intriguing properties of the powerful (Lbol ∼ 1047 erg s-1) radio-loud quasar 3C 186. This object shows peculiar features both in the images and in the spectra. Methods. We utilize near-IR Hubble Space Telescope (HST) images to study the properties of the host galaxy, and HST UV and Sloan Digital Sky Survey …
A Multi-Band Study Of The Remarkable Jet In Quasar 4c+19.44, Daniel E. Harris, Eric S. Perlman
A Multi-Band Study Of The Remarkable Jet In Quasar 4c+19.44, Daniel E. Harris, Eric S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
We present arcsecond-resolution data in the radio, IR, optical, and X-ray for 4C+19.44 (=PKS 1354+195), the longest and straightest quasar jet with deep X-ray observations. We report results from radio images with half to one arcsecond angular resolution at three frequencies, plus Hubble Space Telescope and Spitzer data. The Chandra data allow us to measure the X-ray spectral index in 10 distinct regions along the 18″ jet and compare with the radio index. The radio and X-ray spectral indices of the jet regions are consistent with a value of throughout the jet, to within uncertainties. The X-ray jet structure to …
An Hst Proper-Motion Study Of The Large Scale Jet Of 3c273, Eileen T. Meyer, William B. Sparks, Markos Georganopoulos, Jay Anderson, Roeland Van Der Marel, John Biretta, Sangmo Tony Sohn, Marco Chiaberge, Eric S. Perlman, Colin Norman
An Hst Proper-Motion Study Of The Large Scale Jet Of 3c273, Eileen T. Meyer, William B. Sparks, Markos Georganopoulos, Jay Anderson, Roeland Van Der Marel, John Biretta, Sangmo Tony Sohn, Marco Chiaberge, Eric S. Perlman, Colin Norman
Aerospace, Physics, and Space Science Faculty Publications
The radio galaxy 3C 273 hosts one of the nearest and best-studied powerful quasar jets. Having been imaged repeatedly by the Hubble Space Telescope (HST) over the past twenty years, it was chosen for an HST program to measure proper motions in the kiloparsec-scale resolved jets of nearby radio-loud active galaxies. The jet in 3C 273 is highly relativistic on sub-parsec scales, with apparent proper motions up to 15c observed by very long baseline interferometry. In contrast, we find that the kiloparsec-scale knots are compatible with being stationary, with a mean speed of -0.2 ±0.5c over the whole jet. Assuming …
Optical Detection Of The Pictor A Jet And Tidal Tail: Evidence Against An Ic/Cmb Jet, Eric S. Gentry, Herman L. Marshall, Martin J. Hardcastle, Eric S. Perlman, Mark Birkinshaw, Diana M. Worrall, Emil Lenc, Aneta Siemiginowska, Claudia Megan Urry
Optical Detection Of The Pictor A Jet And Tidal Tail: Evidence Against An Ic/Cmb Jet, Eric S. Gentry, Herman L. Marshall, Martin J. Hardcastle, Eric S. Perlman, Mark Birkinshaw, Diana M. Worrall, Emil Lenc, Aneta Siemiginowska, Claudia Megan Urry
Aerospace, Physics, and Space Science Faculty Publications
New images of the FR II radio galaxy Pictor A from the Hubble Space Telescope reveal a previously undiscovered tidal tail, as well as a number of jet knots coinciding with a known X-ray and radio jet. The tidal tail is approximately 5″ wide (3 kpc projected), starting 18″ (12 kpc) from the center of Pictor A, and extends more than 90″ (60 kpc). The knots are part of a jet observed to be about 4′ (160 kpc) long, extending to a bright hotspot. These images are the first optical detections of this jet, and by extracting knot flux densities …
Ruling Out Ic/Cmb X-Rays In Pks 0637-752 And The Implications For Tev Emission From Large-Scale Quasar Jets, Eileen T. Meyer, Markos Georganopoulos, William B. Sparks, Leith E.H. Godfrey, James E.J. Lovell, Eric S. Perlman
Ruling Out Ic/Cmb X-Rays In Pks 0637-752 And The Implications For Tev Emission From Large-Scale Quasar Jets, Eileen T. Meyer, Markos Georganopoulos, William B. Sparks, Leith E.H. Godfrey, James E.J. Lovell, Eric S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
The Chandra X-ray observatory has discovered dozens of resolved, kiloparsec-scale jets associated with powerful quasars in which the X-ray fluxes are observed to be much higher than the expected level based on the radio-optical synchrotron spectrum. The most popular explanation for the anomalously high and hard X-ray fluxes is that these jets do not decelerate significantly by the kiloparsec scale, but rather remain highly relativistic (Lorentz factors ). By adopting a small angle to the line of sight, the X-rays can thus be explained by inverse Compton upscattering of cosmic microwave background (CMB) photons (IC/CMB), where the observed emission is …
Emission Lines Properties Of The Radio-Loud Quasar Lamost J1131+3114, Zhixin Shi, Georges Comte, Ali L. Luo, Tuehong H. Zhao, Jingkun K. Zhao, T D. Oswalt, Fuchao C. Wu
Emission Lines Properties Of The Radio-Loud Quasar Lamost J1131+3114, Zhixin Shi, Georges Comte, Ali L. Luo, Tuehong H. Zhao, Jingkun K. Zhao, T D. Oswalt, Fuchao C. Wu
Aerospace, Physics, and Space Science Faculty Publications
The radio-loud quasar LAMOST J1131+3114 (Ton 580, B2 1128+315), showing asymmetrical profile in Hβ and [O III] lines, has been selected from the LAMOST Pilot Survey for further study. We present an analysis of its emission lines by means of multiple Gaussian fitting, performed on LAMOST, Apache Point Observatory, and archival spectra. The broad line region, with an Hβ line of FWHM ~ 4000 km sˉ¹ has been fit with a double Gaussian, one of which is very broad and redshifted from the reference frame. The object is a likely Population B quasar. The [O III] λλ4959,5007 lines profiles of …
Polarimetry And The High-Energy Emission Mechanisms In Quasar Jets: The Case Of Pks 1136-135, Mihai Cara, Eric S. Perlman
Polarimetry And The High-Energy Emission Mechanisms In Quasar Jets: The Case Of Pks 1136-135, Mihai Cara, Eric S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
Since the discovery of kiloparsec-scale X-ray emission from quasar jets, the physical processes responsible for their high-energy emission have been poorly defined. A number of mechanisms are under active debate, including synchrotron radiation, inverse-Comptonized cosmic microwave background (IC/CMB) emission, and other Comptonization processes. In a number of cases, the optical and X-ray emission of jet regions are inked by a single spectral component, and in those, high-resolution multi-band imaging and polarimetry can be combined to yield a powerful diagnostic of jet emission processes. Here we report on deep imaging photometry of the jet of PKS 1136−135 obtained with the Hubble …
Periodic Structure In The Megaparsec-Scale Jet Of Pks 0637-752, L. E.H. Godfrey, E. S. Perlman
Periodic Structure In The Megaparsec-Scale Jet Of Pks 0637-752, L. E.H. Godfrey, E. S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
We present 18 GHz Australia Telescope Compact Array imaging of the megaparsec-scale quasar jet PKS 0637–752 with angular resolution ~0farcs58. We draw attention to a spectacular train of quasi-periodic knots along the inner 11'' of the jet, with average separation ~1.1 arcsec (7.6 kpc projected). We consider two classes of model to explain the periodic knots: those that involve a static pattern through which the jet plasma travels (e.g., stationary shocks) and those that involve modulation of the jet engine. Interpreting the knots as re-confinement shocks implies the jet kinetic power Q jet ~ 1046 erg s–1, but the constant …
A Multi-Wavelength Study Of The Jet, Lobes, And Core Of The Quasar Pks 2101-490, Leith E.H. Godfrey, Eric S. Perlman
A Multi-Wavelength Study Of The Jet, Lobes, And Core Of The Quasar Pks 2101-490, Leith E.H. Godfrey, Eric S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
We present a detailed study of the x-ray, optical, and radio emission from the jet, lobes, and core of the quasar PKS 2101−490 as revealed by new Chandra, Hubble Space Telescope (HST), and ATCA images. We extract the radio to x-ray spectral energy distributions from seven regions of the 13'' jet, and model the jet x-ray emission in terms of Doppler beamed inverse Compton scattering of the cosmic microwave background (IC/CMB) for a jet in a state of equipartition between particle and magnetic field energy densities. This model implies that the jet remains highly relativistic hundreds of kiloparsecs from the …
The 2010 Very High Energy Y-Ray Flare And 10 Years Of Multi-Wavelength Observations Of M 87, A. Abramowski, Mihai Cara, Eric S. Perlman, The H.E.S.S. Collaboration, The Magic Collaboration
The 2010 Very High Energy Y-Ray Flare And 10 Years Of Multi-Wavelength Observations Of M 87, A. Abramowski, Mihai Cara, Eric S. Perlman, The H.E.S.S. Collaboration, The Magic Collaboration
Aerospace, Physics, and Space Science Faculty Publications
The giant radio galaxy M 87 with its proximity (16 Mpc), famous jet, and very massive black hole ((3 – 6) × 109 M ☉) provides a unique opportunity to investigate the origin of very high energy (VHE; E > 100 GeV) γ-ray emission generated in relativistic outflows and the surroundings of supermassive black holes. M 87 has been established as a VHE γ-ray emitter since 2006. The VHE γ-ray emission displays strong variability on timescales as short as a day. In this paper, results from a joint VHE monitoring campaign on M 87 by the MAGIC and VERITAS instruments in …
Optical Polarization And Spectral Variability In The M87 Jet, Eric S. Perlman, Mihai Cara, Matthew Bourque, Raymond C. Simons
Optical Polarization And Spectral Variability In The M87 Jet, Eric S. Perlman, Mihai Cara, Matthew Bourque, Raymond C. Simons
Aerospace, Physics, and Space Science Faculty Publications
During the last decade, M87's jet has been the site of an extraordinary variability event, with one knot (HST-1) increasing by over a factor 100 in brightness. Variability has also been seen on timescales of months in the nuclear flux. Here we discuss the optical-UV polarization and spectral variability of these components, which show vastly different behavior. HST-1 shows a highly significant correlation between flux and polarization, with P increasing from 20% at minimum to >40% at maximum, while the orientation of its electric vector stayed constant. HST-1's optical-UV spectrum is very hard (αUV-O 0.5, F ν ∞ ν-α), and …
Deep Multiwaveband Observations Of The Jets Of 0208-512 And 1202-262, Eric S. Perlman
Deep Multiwaveband Observations Of The Jets Of 0208-512 And 1202-262, Eric S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
We present deep Hubble Space Telescope, Chandra, Very Large Array, and Australia Telescope Compact Array images of the jets of PKS 0208-512 and PKS 1202-262, which were found in a Chandra survey of a flux-limited sample of flat-spectrum radio quasars with jets. We discuss in detail their X-ray morphologies and spectra. We find optical emission from one knot in the jet of PKS 1202-262 and two regions in the jet of PKS 0208-512. The X-ray emission of both jets is most consistent with external Comptonization of cosmic microwave background photons by particles within the jet, while the optical emission is …
An X-Ray Imaging Survey Of Quasar Jets: Testing The Inverse Compton Model, Herman L. Marshall, Jonathan M. Gelbord, Daniel A. Schwartz, David W. Murphey, James E.J. Lovell, Diana M. Worrall, Mark Birkinshaw, Eric S. Perlman, Leith E.H. Godfrey, David L. Jauncey
An X-Ray Imaging Survey Of Quasar Jets: Testing The Inverse Compton Model, Herman L. Marshall, Jonathan M. Gelbord, Daniel A. Schwartz, David W. Murphey, James E.J. Lovell, Diana M. Worrall, Mark Birkinshaw, Eric S. Perlman, Leith E.H. Godfrey, David L. Jauncey
Aerospace, Physics, and Space Science Faculty Publications
We present results from continued Chandra X-ray imaging and spectroscopy of a flux-limited sample of flat spectrum radio-emitting quasars with jet-like extended structure. X-rays are detected from 24 of the 39 jets observed so far. We compute the distribution of αrx, the spectral index between the X-ray and radio bands, showing that it is broad, extending at least from 0.8 to 1.2. While there is a general trend that the radio brightest jets are detected most often, it is clear that predicting the X-ray flux from the radio knot flux densities is risky, so a shallow X-ray survey is the …
A Flare In The Jet Of Pictor A, Herman L. Marshall, Eric S. Perlman
A Flare In The Jet Of Pictor A, Herman L. Marshall, Eric S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
A Chandra X-ray imaging observation of the jet in Pictor A showed a feature that appears to be a flare that faded between 2000 and 2002. The feature was not detected in a follow-up observation in 2009. The jet itself is over 150kpc long and about 1 kpc wide, so finding year-long variability is surprising. Assuming a synchrotron origin of the observed high-energy photons and a minimum energy condition for the outflow, the synchrotron loss time of the X-ray emitting electrons is of order 1200 years, which is much longer than the observed variability timescale. This leads to the possibility …
Spitzer Mid-Infrared Spectroscopy Of Compact Symmetric Objects: What Powers Radio-Loud Active Galactic Nuclei?, Kyle W. Willett, John T. Stocke, Jeremy K. Darling, Eric S. Perlman
Spitzer Mid-Infrared Spectroscopy Of Compact Symmetric Objects: What Powers Radio-Loud Active Galactic Nuclei?, Kyle W. Willett, John T. Stocke, Jeremy K. Darling, Eric S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
We present low- and high-resolution mid-infrared (mid-IR) spectra and photometry for eight compact symmetric objects (CSOs) taken with the Infrared Spectrograph on the Spitzer Space Telescope. The hosts of these young, powerful radio galaxies show significant diversity in their mid-IR spectra. This includes multiple atomic fine-structure lines, H2 gas, polycyclic aromatic hydrocarbon (PAH) emission, warm dust from T = 50 to150 K, and silicate features in both emission and absorption. There is no evidence in the mid-IR of a single template for CSO hosts, but 5/8 galaxies show similar moderate levels of star formation (<10 M ⊙ yr-1 from PAH emission) and silicate dust in a clumpy torus. The total amount of extinction ranges from AV ∼ 10 to 30, and the high-ionization [Ne V] 14.3 and 24.3 μm transitions are not detected for any galaxy in the sample. Almost all CSOs show contributions both from star formation and active galactic nuclei (AGNs), suggesting that they occupy a continuum between pure starbursts and AGNs. This is consistent with the hypothesis that radio galaxies are created following a galactic merger; the timing of the radio activity onset means that contributions to the IR luminosity from both merger-induced star formation and the central AGN are likely. Bondi accretion is capable of powering the radio jets for almost all CSOs in the sample; the lack of [Ne V] emission suggests an advection-dominated accretion flow mode as a possible candidate. Merging black holes (BHs) with M BH > 108 M ⊙ likely exist …
Chandra Observations Of The Radio Galaxy 3c 445 And The Hot Spot X-Ray Emission Mechanism, Eric S. Perlman, Markos Georganopoulos, Emily M. May, Deosthenes Kazanas
Chandra Observations Of The Radio Galaxy 3c 445 And The Hot Spot X-Ray Emission Mechanism, Eric S. Perlman, Markos Georganopoulos, Emily M. May, Deosthenes Kazanas
Aerospace, Physics, and Space Science Faculty Publications
We present new Chandra observations of the radio galaxy 3C 445, centered on its southern radio hot spot. Our observations detect X-ray emission displaced upstream and to the west of the radio-optical hot spot. Attempting to reproduce both the observed spectral energy distribution and the displacement excludes all one-zone models. Modeling of the radio-optical hot spot spectrum suggests that the electron distribution has a low-energy cutoff or break approximately at the proton rest mass energy. The X-rays could be due to external Compton scattering of the cosmic microwave background coming from the fast (Lorentz factor Γ ≈ 4) part of …
Chandra Observations Of The Radio Galaxy 3c 445 And The Hot Spot X-Ray Emission Mechanism, Eric S. Perlman, Markos Georganopoulos, Emily M. May, Demosthenes Kazanas
Chandra Observations Of The Radio Galaxy 3c 445 And The Hot Spot X-Ray Emission Mechanism, Eric S. Perlman, Markos Georganopoulos, Emily M. May, Demosthenes Kazanas
Aerospace, Physics, and Space Science Faculty Publications
We present new Chandra observations of the radio galaxy 3C 445, centered on its southern radio hot spot. Our observations detect X-ray emission displaced upstream and to the west of the radio-optical hot spot. Attempting to reproduce both the observed spectral energy distribution and the displacement excludes all one-zone models. Modeling of the radio-optical hot spot spectrum suggests that the electron distribution has a low-energy cutoff or break approximately at the proton rest mass energy. The X-rays could be due to external Compton scattering of the cosmic microwave background coming from the fast (Lorentz factor Γ ≈ 4) part of …
A Multi-Wavelength Spectral And Polarimetric Study Of The Jet Of 3c 264, Eric S. Perlman
A Multi-Wavelength Spectral And Polarimetric Study Of The Jet Of 3c 264, Eric S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
We present a comprehensive multi-band spectral and polarimetric study of the jet of 3C 264 (NGC 3862). Included in this study are three Hubble Space Telescope (HST) optical and ultraviolet polarimetry data sets, along with new and archival Very Large Array radio imaging and polarimetry, a re-analysis of numerous HST broadband data sets from the near infrared to the far ultraviolet, and a Chandra ACIS-S observation. We investigate similarities and differences between optical and radio polarimetry, in both degree of polarization and projected magnetic field direction. We also examine the broadband spectral energy distribution of both the nucleus and jet …
Variability Timescales In The M87 Jet: Signatures Of E^2 Losses, Discovery Of A Quasi Period In Hst-1, And The Site Of Tev Flaring, Daniel E. Harris, Chi C. Cheung, Łukasz Stawarz, J. A. Biretta, Eric S. Perlman
Variability Timescales In The M87 Jet: Signatures Of E^2 Losses, Discovery Of A Quasi Period In Hst-1, And The Site Of Tev Flaring, Daniel E. Harris, Chi C. Cheung, Łukasz Stawarz, J. A. Biretta, Eric S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
We investigate the variability timescales in the jet of M87 with two goals. The first is to use the rise times and decay times in the radio, ultraviolet, and X-ray light curves of HST-1 to constrain the source size and the energy loss mechanisms affecting the relativistic electron distributions. HST-1 is the first jet knot clearly resolved from the nuclear emission by Chandra and is the site of the huge flare of 2005. We find clear evidence for a frequency-dependent decrease in the synchrotron flux being consistent with E 2 energy losses. Assuming that this behavior is predominantly caused by …
Hubble Space Telescope Observations Of The Quasar Pks 0637-752: Equipartition Electron-Proton Jet From The Most Complete Spectral Coverage To Date, Kushal T. Mehta, Markos Georganopoulos, Eric S. Perlman, Charles A. Padgett, George Chartas
Hubble Space Telescope Observations Of The Quasar Pks 0637-752: Equipartition Electron-Proton Jet From The Most Complete Spectral Coverage To Date, Kushal T. Mehta, Markos Georganopoulos, Eric S. Perlman, Charles A. Padgett, George Chartas
Aerospace, Physics, and Space Science Faculty Publications
We present new Near-Infrared Camera and Multi-Object Spectrometer and attitude control system observations of the quasar jet PKS 0637-752, and we use them, together with existing multiwavelength observations, to produce the most complete spectral coverage of the source to date. We explore the implications of these observations in the context of models for the jet X-ray emission. By relaxing the assumption of equipartition, we undertake an exhaustive study of the parameter space for external Compton off the cosmic microwave background (CMB) (EC/CMB) model. We find that the multiwavelength observations exclude a magnetic-field-dominated jet. Using the method proposed by Georganopoulos et …
The Mid-Infrared Emission Of M87, Eric S. Perlman, Rachel E. Mason, Christopher C. Packham, Nancy A. Levenson, Moshe Elitzur, Justin J. Schaefer, Masatoshi Imanishi, William B. Sparks, James T. Radomski
The Mid-Infrared Emission Of M87, Eric S. Perlman, Rachel E. Mason, Christopher C. Packham, Nancy A. Levenson, Moshe Elitzur, Justin J. Schaefer, Masatoshi Imanishi, William B. Sparks, James T. Radomski
Aerospace, Physics, and Space Science Faculty Publications
We discuss Subaru and Spitzer Space Telescope imaging and spectroscopy of M87 in the mid-infrared (mid-IR) from 5 to 35 μm. These observations allow us to investigate mid-IR emission mechanisms in the core of M87 and to establish that the flaring, variable jet component HST-1 is not a major contributor to the mid-IR flux. The Spitzer data include a high signal-to-noise ratio 15-35 μm spectrum of the knot A/B complex in the jet, which is consistent with synchrotron emission. However, a synchrotron model cannot account for the observed nuclear spectrum, even when contributions from the jet, necessary due to the …