Publications (170)
Reverberation in the Narrow Fe K Line in the Seyfert Galaxy NGC 4151 with XRISM
Jon M. Miller, Aberahmen Zoghbi, Xin Xiang +11
Emission lines that "echo" variations in the ionizing flux produced close to black holes are powerful probes of the central engine. In the Seyfert-1.5 galaxy NGC 4151, high-resolut…
The radio emission in radio-quiet quasars: the VLBA perspective
Sina Chen, Ari Laor, Ehud Behar +2
The origin of the radio emission in radio-quiet quasars (RQQ) is not established yet. We present new VLBA observations at 1.6 and 4.9 GHz of ten RQQ (nine detected), which together…
Have the missing cosmic baryons been found?
Ehud Behar, Shlomo Dado, Arnon Dar +1
The angular power spectrum and polarization of the cosmic microwave background radiation (CMB), the relative abundances of primordial hydrogen, deuterium and helium isotopes, and t…
Radiation Pressure Confinement -- III. The origin of the broad ionization distribution in AGN outflows
Jonathan Stern, Ehud Behar, Ari Laor +2
The winds of ionized gas driven by Active Galactic Nuclei (AGN) can be studied through absorption lines in their X-ray spectra. A recurring feature of these outflows is their broad…
Millimeter-band variability of the radio-quiet nucleus of NGC7469
Ranieri D. Baldi, Ehud Behar, Ari Laor +1
We report short-cadence monitoring of a radio-quiet Active Galactic Nuclei (AGN), NGC7469, at 95 GHz (3 mm) over a period of 70 days with the CARMA telescope. The AGN varies signif…
XRISM Reveals a Remnant Torus in the Low-Luminosity AGN M81*
Jon M. Miller, Ehud Behar, Hisamitsu Awaki +10
Up to 40% of galaxies in the local universe host a low-luminosity active galactic nucleus (LLAGN), making it vital to understand this mode of black hole accretion. However, the pre…
The powerful shocks in RS Oph: NuSTAR X-ray data and a complete review
Marina Orio, Gerardo Juan M. Luna, Ehud Behar +4
In the 2021 outburst of RS Ophiuchi, the gamma- and the X-ray flux were measured quasi-simultaneously from day 1 after the optical peak, offering the first comprehensive view of sh…
High-resolution X-ray spectroscopy and imaging of supernova remnant N132D
Ehud Behar, Andrew P. Rasmussen, R. Gareth Griffiths +4
The observation of the supernova remnant N132D by the scientific instruments on board the XMM-Newton satellite is presented. The X-rays from N132D are dispersed into a detailed lin…
A Fast, Hot Wind from a Nuclear Starburst
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +137
Galaxies with intense star formation often host multiphase, galaxy-scale winds powered by supernovae and fast stellar winds. These are strong enough to disrupt the star-forming int…
Correlated mid-infrared and X-ray outbursts in black hole X-ray binaries: A new route to discovery in infrared surveys
Chris John, Kishalay De, Matteo Lucchini +5
The mid-infrared (MIR; m) bands offer a unique window into understanding accretion and its interplay with jet formation in Galactic black hole X-ray binaries (BHX…
Inner-shell Absorption Lines of Fe~VI-- Fe~XVI: A Many-body Perturbation Theory Approach
Ming F. Gu, Tomer Holczer, Ehud Behar +1
We provide improved atomic calculation of wavelengths, oscillator strengths, and autoionization rates relevant to the inner-shell transitions of Fe~VI--XVI, the so-called…
The Advanced X-ray Imaging Satellite (AXIS) Community Science Book
Michael Koss, Nafisa Aftab, Steven W. Allen +395
The AXIS Community Science Book represents the collective effort of 592 scientists worldwide to define the transformative science enabled by the Advanced X-ray Imaging Satellite (A…
The Chandra Iron-L X-Ray Line Spectrum of Capella
Ehud Behar, Jean Cottam, Steven M. Kahn
An analysis of the iron L-shell emission in the publicly available spectrum of the Capella binary system, as obtained by the High Energy Transmission Grating Spectrometer on board…
Comparing XRISM cluster velocity dispersions with predictions from cosmological simulations: are feedback models too ejective?
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +147
The dynamics of the intra-cluster medium (ICM), the hot plasma that fills galaxy clusters, are shaped by gravity-driven cluster mergers and feedback from supermassive black holes (…
Constraints on The Hadronic Content of Gamma Ray Bursts
Lee Yacobi, Dafne Guetta, Ehud Behar
The IceCube high-energy neutrino telescope has been collecting data since 2006. Conversely, hundreds of Gamma Ray Bursts (GRBs) have been detected by the GBM on board Fermi, since…
Ultra High Energy Neutrinos from Gamma-Ray Burst Afterglows Using the Swift-UVOT Data
Guy Nir, Dafne Guetta, Hagar Landsman +1
We consider a sample of 107 Gamma Ray Bursts (GRBs) for which early UV emission was measured by Swift, and extrapolate the photon intensity to lower energies. Protons accelerated i…
Probing Accretion Disk Winds of Stratified Nature with Fe XXVI Doublet in Black Hole X-ray Binaries
Keigo Fukumura, Shoji Ogawa, Atsushi Tanimoto +6
Powerful ionized accretion disk winds are often observed during episodic outbursts in Galactic black hole transients. Among those X-ray absorbers, \fexxvi\ doublet structure (Ly$α…
Modeling spatially-resolved galactic H emission for galaxy clustering
Ivan Rapoport, Vincent Desjacques, Gabriele Parimbelli +2
Near-infrared spectroscopic surveys target high-redshift emission-line galaxies (ELGs) to probe cosmological scenarios. Understanding the clustering properties of ELGs is essential…
XRISM/Resolve Spectroscopy of the Central Engine in the Seyfert-1 AGN Mrk 279
Jon M. Miller, Xin Xiang, Doyee Byun +9
High-resolution X-ray spectroscopy with XRISM gives an unprecedented view of the ``central engine'' in active galactic nuclei, providing unique insights into black hole accretion a…
A Long Look at NGC 3783 with the XMM-Newton Reflection Grating Spectrometers
Ehud Behar, Andrew P. Rasmussen, Alexander J. Blustin +5
A long 280 ks observation of the Seyfert 1 galaxy NGC 3783 with XMM-Newton is reported. We focus on the oxygen line complex between 17 and 24 A as measured with the RGS spectromete…
Magnetically-Driven Accretion-Disk Winds and Ultra-Fast Outflows in PG1211+143
Keigo Fukumura, Francesco Tombesi, Demosthenes Kazanas +3
We present a study of X-ray ionization of magnetohydrodynamic (MHD) accretion-disk winds in an effort to constrain the physics underlying the highly-ionized ultra-fast outflows (UF…
Low-ionization Metal Absorption at Confronting Cosmological Simulations with Observations
Ivan Rapoport, Ehud Behar, Vincent Desjacques
Low-ionization metal absorption lines provide a primary probe of cool gas in and around galaxies. We confront observations of metal-line absorption in quasar spectra with predictio…
Modeling High-Velocity QSO Absorbers with Photoionized MHD Disk-Winds
Keigo Fukumura, Demosthenes Kazanas, Ioannis Contopoulos +1
We extend our modeling of the ionization structure of magnetohydrodynamic (MHD) accretion-disk winds, previously applied to Seyfert galaxies, to a population of quasi-stellar-objec…
A dichotomy in the 1-24 GHz parsec-scale radio spectra of radio-quiet quasars
Sina Chen, Ari Laor, Ehud Behar +3
We present the pc-scale radio spectra of a representative sample of 13 Palomar-Green radio-quiet quasars, based on our new Very Long Baseline Array (VLBA) observations at 8.4 and 2…
Disentangling Multiple Gas Kinematic Drivers in the Perseus Galaxy Cluster
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +143
Galaxy clusters, the Universe's largest halo structures, are filled with 10-100 million degree X-ray-emitting gas. Their evolution is shaped by energetic processes such as feedback…
Remarkable Spectral Variability of PDS 456
Ehud Behar, Shai Kaspi, James Reeves +3
We report on the highest to date signal-to-noise-ratio X-ray spectrum of the luminous quasar PDS 456, as obtained during two XMM-Newton orbits in September 2007. The present spectr…
Chemical enrichment of the Perseus cluster core seen by XRISM/Resolve
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +143
The intracluster medium (ICM) is rich in chemical elements, produced by core-collapse (SNcc) and Type Ia supernovae (SNIa) over the last 12 Gyr. Whereas cluster outskirts are…
GALI: a Gamma-ray Burst Localizing Instrument
Roi Rahin, Luca Moleri, Alex Vdovin +6
The detection of astrophysical Gamma-Ray Bursts (GRBs) has always been intertwined with the challenge of identifying the direction of the source. Accurate angular localization of b…
Toward a Unified AGN Structure
Demosthenes Kazanas, Keigo Fukumura, Ehud Behar +2
We present a unified model for the structure and appearance of accretion powered sources across their entire luminosity range from galactic X-ray binaries to luminous quasars, with…
Observational Evidence Linking Interstellar UV Absorption to PAH Molecules
Avi Blasberger, Ehud Behar, Hagai B. Perets +2
The 2175 Ã UV extinction feature was discovered in the mid-1960s, yet its physical origin remains poorly understood. One suggestion is absorption by Polycyclic Aromatic Hydrocarbon…
X-Ray Absorption Analysis of NGC3516: Appearance of Fast Components with Increased Source Flux
Tomer Holczer, Ehud Behar
By analyzing the X-ray spectra of NGC 3516 from 2001 and 2006 obtained with the HETGS spectrometer on board the Chandra observatory, we find that the kinematic structure of the out…
Density Profiles in Seyfert Outflows
Ehud Behar
For the past decade, ionized outflows of a few 100 km/s from nearby Seyfert galaxies have been studied in great detail using high resolution X-ray absorption spectra. A recurring f…
Benchmark of the Fe XXV R ratio in photoionized plasma during eclipse of Centaurus X-3 with XRISM/Resolve
Yuto Mochizuki, Masahiro Tsujimoto, Maurice A. Leutenegger +6
The R ratio is a useful diagnostic of the X-ray emitting astrophysical plasmas defined as the intensity ratio of the forbidden over the inter-combination lines in the K line co…
Mapping Cassiopeia A's silicon/sulfur Doppler velocities with XRISM-Resolve
Jacco Vink, Manan Agarwal, Aya Bamba +22
Young supernova remnants (SNRs) provide crucial insights into explosive nucleosynthesis products and their velocity distribution soon after the explosion. However, these velocities…
Magnetic Origin of Black Hole Winds Across the Mass Scale
Keigo Fukumura, Demosthenes Kazanas, Chris Shrader +3
Black hole accretion disks appear to produce invariably plasma outflows that result in blue-shifted absorption features in their spectra. The X-ray absorption-line properties of th…
Comparing shocks in planetary nebulae with the solar wind termination shock
Noam Soker, Roi Rahin, Ehud Behar +1
We show that suprathermal particles, termed pick-up ions (PUIs), might reduce the postshock temperature of the fast wind and jets in some planetary nebulae (PNs) and in symbiotic s…
Observation of A Solar Like Magnetic Reconnection Event in an AGN Corona with XRISM
Gal Vardi, Ehud Behar, Liyi Gu +14
The authors present the first direct observation of a magnetic reconnection flare in the X‑ray corona of the active galaxy NGC 3783, using XRISM and XMM‑Newton data that reveal a N…
A NICER viewing angle on the accretion stream of Vela X-1
Roi Rahin, Ehud Behar
Vela X-1 is the archetypical eclipsing high-mass X-ray binary, composed of a neutron star (NS) accreting the B-star wind. It was observed by nearly all X-ray observatories, often m…
The physics and astrophysics of X-ray outflows from Active Galactic Nuclei
Sibasish Laha, Randall Smith, Panayiotis Tzanavaris +20
The highly energetic outflows from Active Galactic Nuclei detected in X-rays are one of the most powerful mechanisms by which the central supermassive black hole (SMBH) interacts w…
High-Resolution X-ray Spectroscopy and Modeling of the Absorbing and Emitting Outflow in NGC 3783
Shai Kaspi, W. N. Brandt, Hagai Netzer +6
(abridged) The high-resolution X-ray spectrum of NGC 3783 shows several dozen absorption lines and a few emission lines from the H-like and He-like ions of O, Ne, Mg, Si, and S as…
Redshifted iron emission and absorption lines in the Chandra X-ray spectrum of Centaurus A
David Bogensberger, Jon Miller, Elias Kammoun +9
Cen A hosts the closest active galactic nucleus to the Milky Way, which makes it an ideal target for investigating the dynamical processes in the vicinity of accreting supermassive…
XRISM Spectroscopy of Accretion-Driven Wind Feedback in NGC 4151
Xin Xiang, Jon M. Miller, Ehud Behar +17
The hottest, most ionized, and fastest winds driven by accretion onto massive black holes have the potential to reshape their host galaxies. Calorimeter-resolution X-ray spectrosco…
A radio, optical, UV and X-ray view of the enigmatic changing look Active Galactic Nucleus 1ES~1927+654 from its pre- to post-flare states
Sibasish Laha, Eileen Meyer, Agniva Roychowdhury +17
The nearby type-II AGN 1ES1927+654 went through a violent changing-look (CL) event beginning December 2017 during which the optical and UV fluxes increased by four magnitudes over…
Hubble Space Telescope Ultraviolet Spectroscopy of Fourteen Low-Redshift Quasars
Rajib Ganguly, Michael S. Brotherton, Nahum Arav +35
We present low-resolution ultraviolet spectra of 14 low redshift (z<0.8) quasars observed with HST/STIS as part of a Snap project to understand the relationship between quasar outf…
Can the soft X-ray opacity towards high redshift sources probe the missing baryons?
Ehud Behar, Shlomo Dado, Arnon Dar +1
Observations with the Swift satellite of X-ray afterglows of more than a hundred gamma ray bursts (GRBs) with known redshift reveal ubiquitous soft X-ray absorption. The directly m…
Chemical Abundances in AGN Environment: X-Ray/UV Campaign on the MRK 279 Outflow
Nahum Arav, Jack R. Gabel, Kirk T. Korista +11
We present the first reliable determination of chemical abundances in an AGN outflow. The abundances are extracted from the deep and simultaneous FUSE and HST/STIS observations of…
Simultaneous Millimeter-wave and X-ray monitoring of the Seyfert Galaxy NGC 7469
Ehud Behar, Shai Kaspi, Gabriel Paubert +6
We report on daily monitoring of the Seyfert galaxy NGC 7469, around 95 GHz and 143 GHz, with the IRAM 30 m radio telescope, and with the Swift X-Ray and UV/Optical telescopes, ove…
Multi-layered Fast Wind observed in XMM-Newton snapshot of Seyfert 1 Markarian 877
Xin Xiang, Jon M. Miller, Ehud Behar +4
Ultra Fast Outflows (UFOs) are powerful, highly ionized winds launched from the innermost regions of Active Galactic Nuclei (AGNs), reaching velocities of 0.03 -- 0.3 c and playing…
X-Ray Emission from Planetary Nebulae Calculated by 1D Spherical Numerical Simulations
Muhammad Akashi, Noam Soker, Ehud Behar +1
We calculate the X-ray emission from both constant and time evolving shocked fast winds blown by the central stars of planetary nebulae (PNs) and compare with observations. Using s…
XRISM constraints on unidentified X-ray emission lines, including the 3.5 keV line, in the stacked spectrum of ten galaxy clusters
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +150
We stack 3.75 Megaseconds of early XRISM Resolve observations of ten galaxy clusters to search for unidentified spectral lines in the 2.5-15 keV band (rest frame), including t…
XRISM forecast for the Coma cluster: stormy, with a steep power spectrum
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +142
The XRISM Resolve microcalorimeter array measured the velocities of hot intracluster gas at two positions in the Coma galaxy cluster: 3'x3' squares at the center and at 6' (170 kpc…
Quasi-simultaneous observations of radio and X-ray variability in three radio-quiet Seyfert galaxies
Sina Chen, Ari Laor, Ehud Behar
Radio variability in some radio-quiet (RQ) active galactic nuclei suggests emission from regions close to the central engine, possibly the outer accretion disc corona. If the origi…
Radio spectra of narrow-line Seyfert 1 galaxies observed with ATCA and VLASS
Sina Chen, Jamie B. Stevens, Philip G. Edwards +7
We present radio spectral analyses for a sample of 29 radio-quiet (RQ) and three radio-loud (RL) narrow-line Seyfert 1 galaxies (NLS1s) detected with the Australia Telescope Compac…
X-Ray Spectrum of RBS 315: Absorption or Intrinsic Curvature
Sivan Ben Haim, Ehud Behar, Richard F. Mushotzky
X-ray absorption of high-redshift quasars is enigmatic, because it remains unclear where in the universe the absorbing gas is. If absorption occurs near the high-z host, it could h…
Reverberation Mapping of the Intermediate Mass Nuclear Black Hole in SDSS J114008.71+030711.4
Stephen Rafter, Shai Kaspi, Ehud Behar +2
We present the results of a reverberation mapping (RM) campaign on the black hole (BH) associated with the active galactic nucleus (AGN) in SDSS J114008.71+030711.4 (hereafter GH08…
GALI -- A GAmma-ray burst Localizing Instrument: Results from Full Size Engineering Model
Julia Saleh-Natur, Ehud Behar, Omer Reich +9
We present a full-size engineering model of GALI - The GAmma-ray burst Localizing Instrument, composed of 362 CsI(Tl) small cubic scintillators, distributed within a small volume o…
The High-Velocity Outflow of PG 1211+143: An Unbiased View Based on Several Observations
Shai Kaspi, Ehud Behar
We present and discuss high-resolution grating spectra of the quasar PG1211+143 obtained over three years. Based on an early observation from 2001, we find an outflow component of…
Discovery of Powerful Multi-Velocity Ultra-Fast Outflows in the Starburst Merger Galaxy IRAS 051892524 with XRISM
Hirofumi Noda, Satoshi Yamada, Shoji Ogawa +17
We observed the X-ray-bright ultra-luminous infrared galaxy, IRAS 051892524, with XRISM during its performance verification phase. The unprecedented energy resolution of the onb…
Elemental Abundances in X-ray Binary Outflows
Noa Keshet, Ehud Behar, Jon M. Miller
Line resolved X-ray spectra of outflows from X-ray binaries are interesting since they provide quantifiable measures of the accreted material on to the compact object (black hole o…
High Spectral Resolution X-ray Observations of the Evolved Supermassive Stellar Binary System Carinae - Iron K Band Profile Revealed with XRISM
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +138
The supermassive binary system, Carinae, is experiencing enormous wind-driven mass loss at a rate unparalleled in the rest of the Galaxy. Their wind-wind collision (WWC) conti…
Stratified Magnetically-Driven Accretion-Disk Winds and Their Relations to Jets
Keigo Fukumura, Francesco Tombesi, Demosthenes Kazanas +3
We explore the poloidal structure of two-dimensional (2D) MHD winds in relation to their potential association with the X-ray warm absorbers (WAs) and the highly-ionized ultra-fast…
Delving into the depths of NGC 3783 with XRISM. I. Kinematic and ionization structure of the highly ionized outflows
Missagh Mehdipour, Jelle S. Kaastra, Megan E. Eckart +17
We present our study of the XRISM observation of the Seyfert-1 galaxy NGC 3783. XRISM's Resolve microcalorimeter has enabled, for the first time, a detailed characterization of the…
Constraining gas motion and non-thermal pressure beyond the core of the Abell 2029 galaxy cluster with XRISM
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +137
We report a detailed spectroscopic study of the gas dynamics and hydrostatic mass bias of the galaxy cluster Abell 2029, utilizing high-resolution observations from XRISM Resolve.…
Energy shift of Fe-K fluorescence lines due to low ionization demonstrated with XRISM in Centaurus X-3
Yutaro Nagai, Teruaki Enoto, Masahiro Tsujimoto +13
The Fe K fluorescence line at 6.4 keV is a powerful probe of cold matter surrounding X-ray sources and has been widely used in various astrophysical contexts. The X-ray microca…
Mixing of hot shocked plasma with cold gas in Nova YZ Ret 2020
Sharon Mitrani, Ehud Behar, Jeremy J. Drake +5
The origin of bright X-ray emission lines that appear late in a nova eruption remains largely a puzzle. We present two high-resolution X-ray grating spectra of the classical nova Y…
Ionization Distributions in Outflows of Active Galaxies: Universal Trends and Prospect of Future XRISM Observations
Noa Keshet, Ehud Behar
The physics behind the ionization structure of outflows from black holes is yet to be fully understood. Using archival observations with the Chandra\HETG gratings over the past two…
Laboratory Measurement and Theoretical Modeling of K-shell X-ray Lines from Inner-shell Excited and Ionized Ions of Oxygen
Ming Feng Gu, Mike Schmidt, Peter Beiersdorfer +5
We present high resolution laboratory spectra of K-shell X-ray lines from inner-shell excited and ionized ions of oxygen, obtained with a reflection grating spectrometer on the ele…
MHD Accretion-Disk Winds as X-ray Absorbers in AGNs
Keigo Fukumura, Demosthenes Kazanas, Ioannis Contopoulos +1
We present the 2D ionization structure of self-similar MHD winds off accretion disks around irradiated by a central X-ray source. Based on earlier observational clues and theoretic…
XRISM finds the Changing-Look AGN NGC 1365 in an extended low state: A dense, highly ionized outflow obscures the central source
Fatima Zaidouni, Erin Kara, Peter Kosec +21
We present the first XRISM/Resolve observations of the active galactic nucleus, NGC 1365, obtained in 2024 February and July. NGC 1365 is known for rapid transitions between Compto…
Windy or not: Radio pc-scale evidence for a broad-line region wind in radio-quiet quasars
Sina Chen, Ari Laor, Ehud Behar +6
Does a broad-line region (BLR) wind in radio-quiet (RQ) active galactic nuclei (AGN) extend to pc scales and produce radio emission? We explore the correlations between a pc-scale…
The SKA-VLBI Perspective on Radio-Quiet AGN
Francesca Panessa, Tao An, James Petley +21
The accretion-ejection mechanism in Active Galactic Nuclei (AGN) remains a central open problem in astrophysics, tied to the role of AGN feedback in galaxy formation and evolution.…
X-ray/UV Observing Campaign on the Mrk 279 AGN Outflow: A Global Fitting Analysis of the UV Absorption
Jack R. Gabel, Nahum Arav, Jelle S. Kaastra +12
We present an analysis of the intrinsic UV absorption in the Seyfert 1 galaxy Mrk 279 based on simultaneous long observations with the Hubble Space Telescope (41 ks) and the Far Ul…
X-ray Observations of Nova Scorpii 2023 (V1716 Sco) in Outburst
John Worley, Marina Orio, Andrej Dobrotka +5
Nova Scorpii 2023 was first detected as a luminous supersoft X-ray source (SSS) 93 days after outburst and continued emitting soft X-rays for over two months, until it was too clos…
Measuring the asymmetric expansion of the Fe ejecta of Cassiopeia A with XRISM/Resolve
Aya Bamba, Manan Agarwal, Jacco Vink +24
The expansion structure of supernova remnants (SNRs) is important for understanding not only how heavy elements are distributed into space, but also how supernovae explode. The eje…
Classifying AGN by X-ray Hardness Variability
Uria Peretz, Ehud Behar
The physics behind the dramatic and unpredictable X-ray variability of Active Galactic Nuclei (AGN) has eluded astronomers since it was discovered. We present an analysis of Swift…
X-ray absorption of cold gas: Simulating interstellar molecular clouds in the laboratory
Itay Gissis, Amnon Fisher, Ehud Behar
Galactic and extra-galactic sources produce X-rays that are often absorbed by molecules and atoms in giant molecular clouds (GMCs), which provides valuable information about their…
Detection of the orbital modulation of Fe K fluorescence emission in Centaurus X-3 using the high-resolution spectrometer Resolve onboard XRISM
Yuto Mochizuki, Masahiro Tsujimoto, Richard L. Kelley +9
The Fe K fluorescence line emission in X-ray spectra is a powerful diagnostic tool for various astrophysical objects to reveal the distribution of cold matter around photo-ioni…
Nova LMC 2009a as observed with XMM-Newton, compared with other novae
Marina Orio, Andrej Dobrotka, Ciro Pinto +9
We examine four high resolution reflection grating spectrometers (RGS) spectra of the February 2009 outburst of the luminous recurrent nova LMC 2009a. They were very complex and ri…
High-resolution X-ray Spectroscopy of BD +30 3639
Joel H. Kastner, Young Sam Yu, John Houck +3
We present preliminary results from the first X-ray gratings spectrometer observations of a planetary nebula (PN). We have used the Chandra X-ray Observatory Low Energy Transmissio…
The 0.9 Megasecond XRISM/Resolve Spectrum of the Seyfert-1 AGN NGC 4151
Jon M. Miller, Xin Xiang, Missagh Mehdipour +13
NGC 4151 is the brightest Seyfert-1 active galaxy in the pass band of the Resolve calorimeter spectrometer aboard XRISM. It has been observed on 14 occasions, resulting in a total…
Dissecting the Nuclear Structure of NGC 5548 with XRISM. I. Physical Properties of the Highly Ionized Outflows
Missagh Mehdipour, Jon M. Miller, Jelle S. Kaastra +21
We present a detailed spectral analysis of an X-Ray Imaging and Spectroscopy Mission (XRISM) observation of the prototypical Seyfert 1 galaxy NGC 5548. XRISM's Resolve microcalorim…
X-ray properties of coronal emission in radio quiet Active Galactic Nuclei
Sibasish Laha, Claudio Ricci, John C. Mather +5
Active galactic nuclei (AGN) are powerful sources of panchromatic radiation. All AGN emit in X-rays, contributing around of the AGN bolometric luminosity. The X-ray e…
Soft X-ray Spectra of Seyfert 2 Galaxies
Masao Sako, Ali Kinkhabwala, Steven M. Kahn +6
High resolution spectroscopic observations of Seyfert galaxies with Chandra and XMM-Newton allows us to study the detailed ionization and thermal structures of the X-ray absorbing/…
Variability of the X-ray obscuring wind in Mrk 335 with XMM-Newton/RGS
Daniele Rogantini, Erin Kara, Luigi Gallo +10
The paper analyzes X‑ray spectra of the Seyfert galaxy Mrk 335 to characterize a multi‑phase, clumpy accretion‑disk wind that shows strong variability on day‑scale timescales and a…
Shocks in the outflow of the RS Oph 2021 eruption observed with X-ray gratings
Marina Orio, Ehud Behar, Juan Luna +9
The 2021 outburst of the symbiotic recurrent nova RS Oph was observed with the Chandra High Energy Transmission Gratings (HETG) on day 18 after optical maximum and with XMM-Newton…
Delving into the depths of NGC 3783 with XRISM III. Birth of an ultrafast outflow during a soft flare
Liyi Gu, Keigo Fukumura, Jelle Kaastra +18
The 2024 X-ray/UV observation campaign of NGC 3783, led by XRISM, revealed the launch of an ultrafast outflow (UFO) with a radial velocity of 0.19c (57000 km/s). This event is sync…
XRISM Spectroscopy of the Stellar-Mass Black Hole 4U 1630-472 in Outburst
Jon M. Miller, Misaki Mizumoto, Megumi Shidatsu +23
We report on XRISM/Resolve spectroscopy of the recurrent transient and well-known black hole candidate 4U 1630472 during its 2024 outburst. The source was captured at the end of…
A Sharper View of the X-ray Spectrum of MCG--6-30-15 with XRISM, XMM-Newton and NuSTAR
Laura W. Brenneman, Daniel R. Wilkins, Anna OgorzaÅek +15
We present a time-averaged spectral analysis of the 2024 XRISM observation of the narrow-line Seyfert-1 galaxy MCG--6-30-15, taken contemporaneously with XMM-Newton and NuSTAR. Our…
Evidence for Charge Exchange Emission in Supernova Remnant N132D from XRISM/Resolve Observations
Liyi Gu, Hiroya Yamaguchi, Adam Foster +24
XRISM has delivered one of its first light observations on N132D, the X-ray brightest supernova remnant in the Large Magellanic Cloud. Utilizing 193 ks of high-resolution X-ray spe…
The Great Slump: Mrk926 reveals discrete and varying Balmer line satellite components during a drastic phase of decline
Wolfram Kollatschny, Martin W. Ochmann, Shai Kaspi +9
Mrk926 is known to be a highly variable AGN with very broad line profiles. We studied the continuum and line profile variations of this object with high temporal resolution in orde…
The Origin of Radio Emission from Radio-Quiet AGN
Francesca Panessa, Ranieri D. Baldi, Ari Laor +3
The central nuclei of galaxies, where super-massive black holes (SMBHs) are thought to reside, can experience phases of activity when they become Active Galactic Nuclei (AGN). An A…
Narrow Radiative Recombination Continua: A Signature of Ions Crossing the Contact Discontinuity of Astrophysical Shocks
Raanan Nordon, Ehud Behar, Noam Soker +2
X-rays from planetary nebulae (PNs) are believed to originate from a shock driven into the fast stellar wind (v ~ 1000 km/s) as it collides with an earlier circumstellar slow wind…
Variable Nature of Magnetically-Driven Ultra-Fast Outflows
Keigo Fukumura, Demosthenes Kazanas, Chris Shrader +3
Among a number of active galactic nuclei (AGNs) that drive ionized outflows in X-rays, a low-redshift (z = 0.184) quasar, PDS 456, is long known to exhibit one of the exemplary ult…
Multi-wavelength campaign on NGC7469 I. The rich 640 ks RGS spectrum
Ehud Behar, Uria Peretz, Gerard A. Kriss +15
Outflows in active galaxies (AGNs) are common, although their launching mechanism, location, and physical impact on the host galaxy remain controversial. We conducted a multiwavele…
AGN STORM 2: X. The origin of the interband continuum delays in Mrk 817
Hagai Netzer, Michael R. Goad, Aaron J. Barth +26
The local (z=0.0315) AGN Mrk 817, was monitored over more than 500 days with space-borne and ground-based instruments as part of a large international campaign AGN STORM 2. Here, w…
Implication of the non-detection of neutrinos above 2PeV
Lee Yacobi, Dafne Guetta, Ehud Behar
The IceCube telescope has detected diffuse neutrino emission, 20 events of which were reported to be above 60~TeV. In this paper, we fit the diffuse neutrino spectrum using Poisson…
Supernova Archaeology with X-Ray Binary Winds -- The Case of GRO J1655-40
Noa Keshet, Ehud Behar, Timothy R. Kallman
Supernovae are responsible for the elemental enrichment of the galaxy and some are postulated to leave behind a black hole. In a stellar binary system the supernova pollutes its co…
Simultaneous Ultraviolet and X-ray Observations of the Seyfert Galaxy NGC 4151. I. Physical Conditions in the X-ray Absorbers
S. B. Kraemer, I. M. George, D. M. Crenshaw +9
We present a detailed analysis of the intrinsic X-ray absorption in the Seyfert 1 galaxy NGC 4151 using Chandra/HETGS data obtained 2002 May, as part of a program which included si…
Hard-X-ray-selected Active Galactic Nuclei -- II. Spectral Energy Distributions in the 5-45 GHz domain
Francesca Panessa, Elia Chiaraluce, Gabriele Bruni +7
A wide-frequency radio study of Active Galactic Nuclei (AGN) is crucial to evaluate the intervening radiative mechanisms responsible for the observed emission and relate them with…
Radio-loud Narrow Line Seyfert 1 under a different perspective: a revised black hole mass estimate from optical spectropolarimetry
Ranieri D. Baldi, Alessandro Capetti, Andrew Robinson +2
Several studies indicate that radio-loud (RL) Active Galactic Nuclei (AGN) are produced only by the most massive black holes (BH), -. This id…