Bogdanovic, Tamara, Eracleous, Michael, Sigurdsson, Steinn
Detection of electromagnetic (EM) counterparts of pre-coalescence binaries has very important implications for our understanding of the evolution of these systems as well as the associated accretion...
Luminous Thermal Flares from Quiescent Supermassive Black Holes (2009)
Gezari, Suvi, Heckman, Tim, Cenko, S. Bradley, Eracleous, Michael, Forster, Karl, Gonçalves, Thiago S., ...
A dormant supermassive black hole lurking in the center of a galaxy will be revealed when a star passes close enough to be torn apart by tidal forces, and a flare of electromagnetic radiation is...
Luminous Thermal Flares from Quiescent Supermassive Black Holes (2009)
Gezari, Suvi, Heckman, Tim, Cenko, S. Bradley, Eracleous, Michael, Forster, Karl, Goncalves, Thiago S., ...
A dormant supermassive black hole lurking in the center of a galaxy will be revealed when a star passes close enough to be torn apart by tidal forces, and a flare of electromagnetic radiation is...
Probing Quiescent Massive Black Holes: Insights from Tidal Disruption Events (2009)
Gezari, Suvi, Strubbe, Linda, Bloom, Joshua S., Grindlay, J. E., Soderberg, Alicia, Elvis, Martin, ...
Tidal disruption events provide a unique probe of quiescent black holes in the nuclei of distant galaxies. The next generation of synoptic surveys will yield a large sample of flares from the tidal...
SDSS J092712.65+294344.0: Recoiling Black Hole or A Sub-parsec Binary Candidate? (2008)
Bogdanovic, Tamara, Eracleous, Michael, Sigurdsson, Steinn
A search for recoiling supermassive black hole candidates recently yielded the best candidate thus far, SDSS J092712.65+294344.0 reported by Komossa et al. Here we propose the alternative hypothesis...
A Chandra Look at Five of the Broadest Double-Peaked Balmer-Line Emitters (2008)
Strateva, Iskra V., Brandt, W. N., Eracleous, Michael, Garmire, Gordon
We study the 0.5-10keV emission of a sample of five of the broadest double-peaked Balmer-line emitters with Chandra. The Balmer lines of these objects originate close (within a few hundred...
In an effort to explain the short-timescale variability of the broad, double-peaked profiles of some active galactic nuclei, we constructed stochastically perturbed accretion disk models and...
Exploratory Study of the X-Ray Properties of Quasars With Intrinsic Narrow Absorption Lines (2008)
Misawa, Toru, Eracleous, Michael, Chartas, George, Charlton, Jane C.
We have used archival Chandra and XMM-Newton observations of quasars hosting intrinsic narrow UV absorption lines (intrinsic NALs) to carry out an exploratory survey of their X-ray properties. Our...
A Chandra look at five of the broadest double-peaked Balmer line emitters (2008)
Strateva, Iskra V., Brandt, W. N., Eracleous, Michael, Garmire, Gordon
Moran, Edward C., Barth, Aaron J., Eracleous, Michael, Kay, Laura E.
We have discovered an extremely broad, double-peaked H-alpha emission line in the polarized flux spectrum of NGC 2110, establishing that this well-studied Seyfert 2 galaxy contains a disk-like hidden...
Modeling of Emission Signatures of Massive Black Hole Binaries: I Methods (2007)
Bogdanovic, Tamara, Smith, Britton D., Sigurdsson, Steinn, Eracleous, Michael
We model the electromagnetic signatures of massive black hole binaries (MBHBs) with an associated gas component. The method comprises numerical simulations of relativistic binaries and gas coupled...
New Ultraviolet Observations of AM CVn (2007)
Wade, Richard A., Eracleous, Michael, ...
We have obtained observations of the ultraviolet spectrum of AM CVn, an ultra-short-period helium cataclysmic variable, using the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space...
Misawa, Toru, Eracleous, Michael, Charlton, Jane C., Kashikawa, Nobunari
We present six new and two previously published high-resolution spectra of the quasar HS 1603+3820 (z_em = 2.542) taken over an interval of 4.2 years (1.2 years in the quasar rest frame). The...
Electromagnetic Signatures of Massive Black Hole Binaries (2006)
Bogdanovic, Tamara, Smith, Britton D., Eracleous, Michael, Sigurdsson, Steinn
We model the electromagnetic emission signatures of massive black hole binaries (MBHBs) with an associated gas component. The method comprises numerical simulations of relativistic binaries and gas...
The X-ray properties of active galactic nuclei with double-peaked balmer lines (2006)
Strateva, Iskra V., Brandt, W. N., Eracleous, Michael, Schneider, Donald P., Chartas, George
Radiatively Inefficient Accretion Flow in the Nucleus of NGC 1097 (2005)
Nemmen, Rodrigo S., Storchi-Bergmann, Thaisa, Yuan, Feng, Eracleous, Michael, Terashima, Yuichi, Wilson, Andrew S.
We present a model for the accretion flow around the supermassive black hole in the LINER nucleus of NGC 1097 which fits the optical to X-ray spectral energy distribution (SED). The X-ray segment of...
Observational Signature of Tidal Disruption of a Star by a Massive Black Hole (2005)
Bogdanovic, Tamara, Eracleous, Michael, Mahadevan, Suvrath, Sigurdsson, Steinn, Laguna, Pablo
We have modeled the time-variable profiles of the Balmer alpha emission from the nonaxisymmetric disk and debris tail created in the tidal disruption of a solar-type star by a million solar mass...
Time-Variable Complex Metal Absorption Lines in the Quasar HS1603+3820 (2005)
Misawa, Toru, Eracleous, Michael, Charlton, Jane C., Tajitsu, Akito
We present a new spectrum of the quasar HS1603+3820 taken 1.28 years (0.36 years in the quasar rest frame) after a previous observation with Subaru+HDS. The new spectrum enables us to search for time...
Extreme X-ray Behavior of the Low-Luminosity Active Nucleus in NGC 4395 (2005)
Moran, Edward C., Eracleous, Michael, Leighly, Karen M., Chartas, George, Filippenko, Alexei V., Ho, Luis C., ...
We present the results of a 17 ks Chandra ACIS-S observation of the nearby dwarf spiral galaxy NGC 4395. Chandra affords the first high-quality, broadband X-ray detection of the active nucleus of...
A Simultaneous RXTE and XMM-Newton Observation of the Broad-Line Radio Galaxy 3C 111 (2004)
Lewis, Karen T., Eracleous, Michael, Gliozzi, Mario, Sambruna, Rita M., Mushotzky, Richard F.
We present the results of simultaneous XMM-Newton and RXTE observations of the Broad-Line Radio Galaxy 3C 111. We find that the Compton reflection bump is extremely weak, however, broad residuals are...
Long-Term Profile Variability of Double-Peaked Emmission Lines in AGNs (2004)
Lewis, Karen T., Eracleous, Michael, Halpern, Jules P., Storchi-Bergmann, Thaisa
An increasing number of AGNs exhibit broad, double-peaked Balmer emission lines, which arise from the outer regions of the accretion disk which fuels the AGN. The line profiles vary on timescales of...
Tidal Disruption of a Star By a Black Hole : Observational Signature (2004)
Bogdanovic, Tamara, Eracleous, Michael, Mahadevan, Suvrath, Sigurdsson, Steinn, Laguna, Pablo
We have modeled the time-variable profiles of the Halpha emission line from the non-axisymmetric disk and debris tail created in the tidal disruption of a solar-type star by a million solar mass...
Observational Signature of Tidal Disruption of a Star by a Massive Black Hole (2004)
Bogdanovic, Tamara, Eracleous, Michael, Mahadevan, Suvrath, Sigurdsson, Steinn, Laguna, Pablo
We have modeled the time-variable profiles of the Halpha emission line from the non-axisymmetric disk and debris tail created in the tidal disruption of a solar-type star by a million solar mass...
A Study of QSO Evolution in the X-Ray Band with the Aid of Gravitational Lensing (2004)
Dai, Xinyu, Chartas, George, Eracleous, Michael, Garmire, Gordon P.
We present results from a mini-survey of relatively high redshift (1.7 < z < 4) gravitationally lensed radio-quiet quasars observed with the Chandra X-ray Observatory and with XMM-Newton. The lensing...
I review the distinguishing observational characteristics of active galaxies with double-peaked emission lines and their implications for the nature of the line-emitting region. Since double-peaked...
Long Term Profile Variability of Double-Peaked Emission Lines in AGNs (2003)
Lewis, Karen T., Eracleous, Michael, Halpern, Jules P., Storchi-Bergmann, Thaisa
An increasing number of AGNs exhibit broad, double-peaked Balmer emission lines, which are thought to arise from the outer regions of the accretion disk which fuels the AGN. The line profiles are...
Accurate Redshifts and Classifications for 110 Radio-Loud AGNs (2003)
Eracleous, Michael, Halpern, Jules P.
We report accurate redshifts of 110 active galaxies (mostly radio-loud objects at z
Emission-Line Diagnostics of the Central Engines of Weak-Line Radio Galaxies (2003)
Lewis, Karen T., Eracleous, Michael, Sambruna, Rita M.
A handful of well-studied Weak-Line Radio Galaxies (WLRGs) have been traditionally classified as Low Ionization Nuclear Emission-line Regions (LINERs), suggesting that these two groups of AGNs might...
Feeding the active nucleus of NGC 1097 (2002)
Storchi-Bergmann, Thaisa, Da Silva, Rodrigo Nemmen, Eracleous, Michael
We discuss the signatures of an evolving accretion disk around the nucleus of NGC 1097, based on observations of its double-peaked H-alpha emission-line profile which cover a time span of 10 yrs. The...
Donley, J. L., Brandt, W. N., Eracleous, Michael, Boller, Th.
In recent years, luminous X-ray outbursts with variability amplitudes as high as 400 have been serendipitously detected from a small number of active and inactive galaxies. These outbursts may result...
Emission Line Diagnostics of Accretion Flows in Weak-Line Radio Galaxies (2001)
Lewis, Karen T., Eracleous, Michael, Sambruna, Rita M.
In recent surveys of Radio-loud AGN, a new sub-class of objects, known as Weak-Line Radio Galaxies (WLRGs) has emerged. These radio galaxies have only weak, low-ionization optical emission lines. In...
Variable UV Absorption in the Spectrum of MRC 2251-178 (2001)
Ganguly, Rajib, Charlton, Jane C., Eracleous, Michael
We present an ultraviolet spectrum of MRC 2251-178 taken with HST/STIS-G230L. The observation is part of a snap shot program of QSOs to systematically search for intrinsic absorption lines through...
NGC 3065: A Certified LINER With Broad, Variable Balmer Lines (2001)
Eracleous, Michael, Halpern, Jules P.
Motivated by the X-ray properties of the galaxy NGC 3065, we have obtained new optical spectra which reveal that it has a low-ionization nuclear emission-line region (LINER) as well as broad Balmer...
On the Origin of Intrinsic Narrow Absorption Lines in z (2000)
Ganguly, Rajib, Bond, Nicholas A., Charlton, Jane C., Eracleous, Michael, Brandt, W. N., Churchill, Christopher W.
We present a statistical analysis of the associated, high ionization narrow absorption line (NAL) systems in a sample of 59 QSOs defined from the HST QSO Absorption Line Key Project. We have compiled...
Double-Peaked Broad Emission Lines in NGC 4450 and Other LINERs (2000)
Ho, Luis C., Rudnick, Greg, Rix, Hans-Walter, Shields, Joseph C., McIntosh, Daniel H., Filippenko, Alexei V., ...
Spectra taken with HST reveal that NGC 4450 emits Balmer emission lines with displaced double peaks and extremely high-velocity wings. This characteristic line profile, previously seen in a few...
Radio-loud AGNs: The X-ray perspective (1999)
Sambruna, Rita M., Eracleous, Michael
The X-ray emission of radio-loud (RL) AGNs is a powerful tool for probing the structure of the accretion flow in these objects. We review recent spectral and variability studies of RL AGNs, which...
Constraining the central engine of radio-loud AGNs (1999)
Sambruna, Rita M., Eracleous, Michael, Mushotzky, Richard
We present an X-ray spectral survey of radio-loud (RL) AGNs using ASCA and RXTE. The goal was to study the structure of their central engines and compare it to that of their radio-quiet (RQ)...
Kaaret, Philip, Piraino, Santina, Halpern, Jules, Eracleous, Michael
We have discovered an x-ray source, SAX J0635+0533, with a hard spectrum within the error box of the GeV gamma-ray source in Monoceros, 2EG J0635+0521. The unabsorbed x-ray flux is 1.2*10^-11 erg...
Intrinsic Narrow Absorption Lines in HIRES/Keck Spectra of a Sample of Six Quasars (1999)
Ganguly, Rajib, Eracleous, Michael, Charlton, Jane C., Churchill, Christopher W.
In the course of a large intervening MgII survey of 25 quasars, the CIV emission lines of six (three radio-loud and three radio-quiet) were observed serendipitously. In four of these six quasars, we...
The Post-Common Envelope and Pre-Cataclysmic Binary PG 1224+309 (1998)
Orosz, Jerome A., Wade, Richard A., Harlow, Jason J. B., Thorstensen, John R., Taylor, Cynthia J., Eracleous, Michael
We have made extensive spectroscopic and photometric observations of PG 1224+309, a close binary containing a DA white dwarf primary and an M4+ secondary. The H alpha line is in emission due to...
ASCA Observations of Radio-Loud AGNs (1998)
Sambruna, Rita, Eracleous, Michael, Mushotzky, Richard
We summarize the results of an X-ray spectroscopic survey of radio-loud AGNs observed with ASCA, using proprietary and archival data (public up to 1998 September). We briefly compare our results with...
Eracleous, Michael, Halpern, Jules P.
We present the X-ray spectrum of the broad-line radio galaxy Pictor A as observed by ASCA in 1996. The main objective of the observation was to detect and study the profiles of the Fe~K$\alpha$...
Optical and X-ray Spectroscopy of 1E 0449.4-1823: Demise of the original type 2 QSO (1998)
Halpern, Jules P., Eracleous, Michael, Forster, Karl
New optical spectra of the original narrow-line quasar 1E 0449.4-1823 show that it now has broad emission lines of considerable strength, eliminating it as a "type 2 QSO" candidate. We suggest that...
HST Observations of IP Pegasi in Quiescence: The Pre-Eclipse Spectrum (1997)
Hoard, D. W., Baptista, Raymundo, Eracleous, Michael, Horne, Keith, Misselt, K. A., Shafter, Allen W., ...
We present time-resolved HST UV spectroscopy and ground-based optical photometry of the dwarf nova IP Peg in a quiescent state. The observations were obtained prior to an eclipse, when the bright...
Newman, Jeffrey A., Eracleous, Michael, Filippenko, Alexei V., Halpern, Jules P.
The optical spectrum of the broad-line radio galaxy Arp 102B has been monitored for more than thirteen years to investigate the nature of the source of its broad, double-peaked hydrogen Balmer...
Department: Astronomy.
Thesis (Ph. D.)--Columbia University, 1992.