315 citations · 2.1k across the 58 of their papers we have counts for
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Implications of the VHE Gamma-Ray Detection of the Quasar 3C279
Markus Boettcher, Anita Reimer, Alan P. Marscher
The MAGIC collaboration recently reported the detection of the quasar 3C279 at > 100 GeV gamma-ray energies. Here we present simultaneous optical (BVRI) and X-ray (RXTE PCA) data f…
Gamma-Ray Studies of Blazars: Synchro-Compton Analysis of Flat Spectrum Radio Quasars
Charles D. Dermer, Justin D. Finke, Hannah Krug +1
We extend a method for modeling synchrotron and synchrotron self-Compton radiations in blazar jets to include external Compton processes. The basic model assumption is that the bla…
The Hard VHE Gamma-ray Emission in High-Redshift TeV Blazars: Comptonization of Cosmic Microwave Background Radiation in an Extended Jet?
Markus Boettcher, Charles D. Dermer, Justin D. Finke
Observations of very-high-energy (VHE, E > 250 GeV) gamma-ray emission from several blazars at z > 0.1 have placed stringent constraints on the elusive spectrum and intensity of th…
Nonthermal Synchrotron and Synchrotron Self-Compton Emission from GRBs: Predictions for {\em Swift} and {\em GLAST}
Justin Finke, Charles Dermer, Markus Boettcher
Results of a leptonic jet model for the prompt emission and early afterglows of GRBs are presented. The synchrotron component is modeled with the canonical Band spectrum and the sy…
Synchrotron Self-Compton Analysis of TeV X-ray Selected BL Lacertae Objects
Justin Finke, Charles Dermer, Markus Boettcher
We introduce a methodology for analysis of multiwavelength data from X-ray selected BL Lac (XBL) objects detected in the TeV regime. By assuming that the radio--through--X-ray flux…
Redshift Limits of BL Lacertae Objects from Optical Spectroscopy
J. D. Finke, J. C. Shields, M. Boettcher +1
Context: BL Lacertae objects have been the targets for numerous recent multiwavelength campaigns, continuum spectral variability studies, and theoretical spectral and variability m…
Multiwavelength Monitoring of the Unusual Ultraluminous Supernova SN 1978K in NGC 1313 and the Search for an Associated Gamma-Ray Burst
I. A. Smith, S. D. Ryder, M. Boettcher +4
We discuss our radio (Australia Telescope Compact Array and Australian Long Baseline Array) and X-ray (XMM-Newton) monitoring observations of the unusual ultraluminous supernova SN…
Modeling the Spectral Energy Distribution and Variability of 3C 66A during the WEBT campaign of 2003 -- 2004
M. Joshi, M. Boettcher
The BL Lac object 3C 66A was observed in an extensive multiwavelength monitoring campaign from July 2003 till April 2004. The spectral energy distribution (SED) was measured over t…
Constraints on the Geometry of the VHE Emission in LS 5039 from Photon-Photon Deabsorption
Markus Boettcher
A detailed parameter study of the gamma-gamma absorption effects in LS 5039 is presented. For a range of plausible locations of the VHE gamma-ray emission region and the allowable…
Coordinated Multiwavelength Observations and Spectral Variability Modeling of Gamma-Ray Blazars
M. Boettcher
Our recent progress on time-dependent modeling of the multiwavelength spectra and variability of blazars with leptonic and hadronic jet models is reviewed. Special emphasis is plac…
The diagnostic power of X-ray emission lines in GRBs
M. Boettcher
Absorption and reprocessing of Gamma-ray burst radiation in the environment of cosmological GRBs can be used as a powerful probe of the elusive nature of their progenitors. Althoug…
BeppoSAX and multiwavelength observations of BL Lacertae in 2000
M. Ravasio, G. Tagliaferri, G. Ghisellini +3
We present two BeppoSAX observations of BL Lac (2200+420) as part of a multiwavelength campaign performed in 2000. The source was in different states of activity: in June, the X-ra…
X-Ray Lines and Absorption Edges in GRBs and Their Afterglows
M. Boettcher
Absorption and Reprocessing of Gamma-ray burst radiation in the environment of cosmological GRBs can be used as a powerful probe of the elusive nature of their progenitors. In part…
Conversion of relativistic pair energy into radiation in the jets of active galactic nuclei
R. Schlickeiser, R. Vainio, M. Boettcher +3
It is generally accepted that relativistic jet outflows power the nonthermal emission from active galactic nuclei (AGN). The composition of these jets -- leptonic versus hadronic -…
Broadband Spectra and Variability of BL Lacertae in 2000
M. Boettcher, H. D. Aller, M. F. Aller +6
We have organized an extensive multiwavelength campaign on BL Lacertae in the second half of 2000. Simultaneous or quasi-simultaneous observations were taken at radio frequencies,…
Pair Production and Radiation Effects in Clouds Illuminated by Gamma Ray Sources
C. D. Dermer, M. Boettcher, E. P. Liang
Many classes of gamma-ray sources, such as gamma-ray bursts, blazars, Seyfert galaxies, and galactic black hole sources are surrounded by large amounts of gas and dust. X-rays and…
Physics Input from Multiwavelength Observations of AGN
M. Boettcher
The current status of leptonic jet models for blazars is reviewed. Differences between the quasar and BL-Lac subclasses of blazars may be understood in terms of the dominance of di…
A model for the alternating phase lags associated with QPOs in X-ray binaries
M. Boettcher, E. P. Liang
We present a theoretical model for the alternating phase lags associated with QPO fundamental and harmonic frequencies observed in some Galactic black-hole candidates. We assume th…
A large high-energy gamma-ray flare from the blazar 3C 273
W. Collmar, O. Reimer, K. Bennett +8
The Compton Gamma-Ray Observatory (CGRO) experiments EGRET and COMPTEL observed the Virgo sky region continuously for 7 weeks between December 10, 1996 and January 28, 1997. The pr…
GRB990123: The Case for Saturated Comptonization
E. P. Liang, A. Crider, M. Boettcher +1
The recent simultaneous detection of optical, X-ray and gamma-ray photons from GRB990123 during the burst provides the first broadband multi-wavelength characterization of the burs…
Time-dependent photoelectric absorption, photoionization and fluorescence line emission in gamma-ray burst environments
M. Boettcher, C. D. Dermer, A. W. Crider +1
If gamma-ray bursts are associated with dense star-forming regions in young galaxies, photoelectric absorption by the dense circumburster material (CBM) will occur. As the burst ev…
Radiation Feedback in Hot Accretion-Disk Corona Models
M. Boettcher, E. P. Liang, I. A. Smith
We present a detailed study of the observable effects of photoionization and Comptonization of line and continuum radiation from a cold accretion disk with a thin, warm, photoioniz…
Spectral modeling of gamma-ray blazars
M. Boettcher, H. Mause, R. Schlickeiser
We present model calculations reproducing broadband spectra of -ray blazars by a relativistic leptonic jet, combining the EIC and the SSC model. To this end, the evolution of th…
The Pair Production Spectrum from Photon-Photon Annihilation
M. Boettcher, R. Schlickeiser
We present the first completely analytical computation of the full differential γ-γpair production rate from compact radiation fields, exact to 2nd order QED, and use this result t…