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Full-Text Articles in Physical Sciences and Mathematics
Multiwavelength Study Of Quiescent States Of Mrk 421 With Unprecedented Hard X-Ray Coverage Provided By Nustar In 2013, P. T. Reynolds, Nustar, Veritas, Magic
Multiwavelength Study Of Quiescent States Of Mrk 421 With Unprecedented Hard X-Ray Coverage Provided By Nustar In 2013, P. T. Reynolds, Nustar, Veritas, Magic
Physical Sciences Publications
We present coordinated multiwavelength observations of the bright, nearby BL Lacertae object Mrk 421 taken in 2013 January–March, involving GASP-WEBT, Swift, NuSTAR, Fermi-LAT, MAGIC, VERITAS, and other collaborations and instruments, providing data from radio to very high energy (VHE) γ-ray bands. NuSTAR yielded previously unattainable sensitivity in the 3–79 keV range, revealing that the spectrum softens when the source is dimmer until the X-ray spectral shape saturates into a steep ${\rm{\Gamma }}\approx 3$ power law, with no evidence for an exponential cutoff or additional hard components up to ~80 keV. For the first time, we observed both the synchrotron and …
First Nustar Observations Of Mrk 501 Within A Radio To Tev Multi-Instrument Campaign, P. T. Reynolds, Nustar, Magic, Veritas, F-Gamma
First Nustar Observations Of Mrk 501 Within A Radio To Tev Multi-Instrument Campaign, P. T. Reynolds, Nustar, Magic, Veritas, F-Gamma
Physical Sciences Publications
We report on simultaneous broadband observations of the TeV-emitting blazar Markarian 501 between 2013 April 1 and August 10, including the first detailed characterization of the synchrotron peak with Swift and NuSTAR. During the campaign, the nearby BL Lac object was observed in both a quiescent and an elevated state. The broadband campaign includes observations with NuSTAR, MAGIC, VERITAS, the Fermi Large Area Telescope, Swift X-ray Telescope and UV Optical Telescope, various ground-based optical instruments, including the GASP-WEBT program, as well as radio observations by OVRO, Metsähovi, and the F-Gamma consortium. Some of the MAGIC observations were affected …
Tev And Multi-Wavelength Observations Of Mrk 421 In 2006-2008, P. T. Reynolds, Et. Al.
Tev And Multi-Wavelength Observations Of Mrk 421 In 2006-2008, P. T. Reynolds, Et. Al.
Physical Sciences Publications
We report on TeV γ-ray observations of the blazar Mrk 421 (redshift of 0.031) with the VERITAS observatory and the Whipple 10 m Cherenkov telescope. The excellent sensitivity of VERITAS allowed us to sample the TeV γ-ray fluxes and energy spectra with unprecedented accuracy where Mrk 421 was detected in each of the pointings. A total of 47.3 hr of VERITAS and 96 hr of Whipple 10 m data were acquired between 2006 January and 2008 June. We present the results of a study of the TeV γ-ray energy spectra as a function of time and for different flux levels. …
Spectral Energy Distribution Of Markarian 501: Quiescent State Versus Extreme Outburst, P. T. Reynolds, Veritas, Magic
Spectral Energy Distribution Of Markarian 501: Quiescent State Versus Extreme Outburst, P. T. Reynolds, Veritas, Magic
Physical Sciences Publications
The very high energy (VHE; E > 100 GeV) blazar Markarian 501 (Mrk 501) has a well-studied history of extreme spectral variability and is an excellent laboratory for studying the physical processes within the jets of active galactic nuclei. However, there are few detailed multiwavelength studies of Mrk 501 during its quiescent state, due to its low luminosity. A short-term multiwavelength study of Mrk 501 was coordinated in 2009 March, focusing around a multi-day observation with the Suzaku X-ray satellite and including γ-ray data from VERITAS, MAGIC, and the Fermi Gamma-ray Space Telescope with the goal of providing a well-sampled multiwavelength …
Simultaneous Multiwavelength Observations Of Markarian 421 During Outburst, P. T. Reynolds, Veritas, Magic
Simultaneous Multiwavelength Observations Of Markarian 421 During Outburst, P. T. Reynolds, Veritas, Magic
Physical Sciences Publications
We report on the results of two coordinated multiwavelength campaigns that focused on the blazar Markarian 421 during its 2006 and 2008 outbursts. These campaigns obtained UV and X-ray data using the XMM-Newton satellite, while the gamma-ray data were obtained utilizing three imaging atmospheric Cerenkov telescopes, the Whipple 10 m telescope and VERITAS, both based in Arizona, as well as the MAGIC telescope, based on La Palma in the Canary Islands. The coordinated effort between the gamma-ray groups allowed for truly simultaneous data in UV/X-ray/gamma-ray wavelengths during a significant portion of the XMM-Newton observations. This simultaneous coverage allowed for a …
A Multiwavelength View Of The Tev Blazar Markarian 421: Correlated Variability, Flaring, And Spectral Evolution, P. T. Reynolds, Veritas
A Multiwavelength View Of The Tev Blazar Markarian 421: Correlated Variability, Flaring, And Spectral Evolution, P. T. Reynolds, Veritas
Physical Sciences Publications
We report results from an intensive multiwavelength monitoring campaign on the TeV blazar Mrk 421 over the period of 2003-2004. The source was observed simultaneously at TeV energies with the Whipple 10 m telescope and at X-ray energies with the Rossi X-Ray Timing Explorer (RXTE) during each clear night within the Whipple observing windows. Supporting observations were also frequently carried out at optical and radio wavelengths to provide simultaneous or contemporaneous coverages. The large amount of simultaneous data has allowed us to examine the variability of Mrk 421 in detail, including cross-band correlation and broadband spectral variability, over a wide …