Markarian 421

Observation Date (UT)	Observation Lat
	ARGO-YBJ (30.11) ASTRI Mini-Array (28.3) CANGAROO (-31.10 ) CAT (42.50) Crimea (45) CTA pSCT (31.68) CTA South (-24.6272) Durham (-30.48) FACT (28.76) H.E.S.S. (-23.16) HAGAR (30) HAWC (19.0) HEGRA (28.76) LHAASO (29.358) LST-1 (28.76) MAGIC (28.76) Milagro (35.88 ) Potchefstroom (-26.9) TACTIC (24.6) TAIGA (103.07) Telescope Array (39.3) Tibet (30.11) VERITAS (31.68) Whipple (31.68)

Canonical Name:	Markarian 421
TeVCat Name:	TeV J1104+382
Other Names:	PG 1101+385 B3 1101+384 RBS 0939 RGB J1104+382 1ES 1101+384 1H 1104+382 H 1105+38 3FGL J1104.4+3812 2HWC J1104+381
Source Type:	HBL
R.A.:	11 04 19 (hh mm ss)
Dec.:	+38 11 41 (dd mm ss)
Gal Long:	179.88 (deg)
Gal Lat:	65.01 (deg)
Distance:	z=0.031
Flux:	0.3 (Crab Units)
Energy Threshold:	500 GeV
Spectral Index:	2.2
Extended:	No
Discovery Date:	1992-08
Discovered By:	Whipple
TeVCat SubCat:	Default Catalog

Source Notes:

Source position and its uncertainty:
From Albert et al. (2007):
- R.A. (J2000): 11 04 19
- Dec. (J2000): +38 11 41
- syst. uncertainty: 2'
- this is consistent with the source position provided by NED

The flux from Markarian 421 is highly variable.
From Ahnen et al. (2016):
Commenting on observations taken with MAGIC between March 2007 and
June 2009:
- "The flux above 400 GeV spans from the minimum nightly value of
1.3 +/- 0.4 10e-11 cm-2 s-1 to the maximum flux, that is about 24
times higher, at 3.1 +/- 0.1 10e-10 cm-2 s-1"

Spectral Index:
The spectral index has been found to vary.
From Albert et al. (2007):
- 2.20 +/- 0.08
- the spectrum shows evidence for an exponential cutoff (independent of EBL absorption)

Information on the jet:
From Lister et al. (2019):
- "All three innermost jet features of this nearby BL Lac object show
inward motion."


Seen by: Whipple, HEGRA, CAT, H.E.S.S., MAGIC, Milagro, Telescope Array, CANGAROO, TACTIC, ARGO-YBJ, HAGAR, FACT, VERITAS, HAWC, LHAASO

• A Study of the Radio Spectrum of Mrk 421
  Lee, Jee Won et al., ApJ 964 p176 (2024) [LINK]
  
• Rapid variability of Markarian 421 during extreme flaring as seen through the eyes of XMM-Newton
  Gokus, A. et al., MNRAS 529 p1450-1462 (2024) [LINK]
  
• Broadband Multiwavelength Study of LHAASO-detected Active Galactic Nuclei
  Wang, Ze-Rui et al., ApJS 271 p10 (2024) [LINK]
  
• Simultaneous X-ray and optical polarization observations of the blazar Mrk 421
  Bharathan, Athira M. et al., arXiv e-prints parXiv:2409.16745 (2024) [LINK]
  
• Two-injection Scenario for the Hard X-Ray Excess Observed in Mrk 421
  Hu, Wen et al., ApJ 948 p82 (2023) [LINK]
  
• Discovery of X-ray polarization angle rotation in active galaxy Mrk 421
  Di Gesu, Laura et al., arXiv e-prints parXiv:2305.13497 (2023) [LINK]
  
• A QPO in Mkn 421 from Archival RXTE Data
  Smith, Evan et al., arXiv e-prints parXiv:2305.07510 (2023) [LINK]
  
• Flux and spectral variability of Mrk 421 during its moderate activity state using NuSTAR: Possible accretion disc contribution?
  Mondal, Santanu et al., arXiv e-prints parXiv:2204.02132 (2022) [LINK]
  
• Do radiative losses determine the characteristic emission of the blazar Mkn 421?
  Baheeja, C. et al., arXiv e-prints parXiv:2206.00659 (2022) [LINK]
  
• X-ray intraday variability of the TeV blazar Mrk 421 with XMM-Newton
  Priyana Noel, A et al., arXiv e-prints parXiv:2206.02159 (2022) [LINK]
  
• Rapid X-ray Variability in Mkn 421 during a Multiwavelength Campaign
  Markowitz, Alex G. et al., arXiv e-prints parXiv:2206.03874 (2022) [LINK]
  
• The X-ray Polarization View of Mrk 421 in an Average Flux State as Observed by the Imaging X-ray Polarimetry Explorer
  Di Gesu, Laura et al., arXiv e-prints parXiv:2209.07184 (2022) [LINK]
  
• Correlations between X-ray spectral parameters of Mkn 421 using long-term Swift-XRT data
  Khatoon, Rukaiya et al., MNRAS 515 p3749-3759 (2022) [LINK]
  
• Probing the Extragalactic Mid-infrared Background with HAWC
  Albert, A. et al., ApJ 933 p223 (2022) [LINK]
  
• Hadronuclear interactions in the jet of low TeV luminosity AGN: Implications for the low-state very-high-energy gamma-ray emission
  Xue, Rui et al., arXiv e-prints parXiv:2210.09797 (2022) [LINK]
  
• Optically thick, nonlocal, inhomogeneous, stationary jet model for high-energy radiation from blazars: Application to Mrk 421
  Banasinski, Piotr and Bednarek, Wlodek, arXiv e-prints parXiv:2211.03762 (2022) [LINK]
  
• Photohadronic Modelling of the 2010 Gamma-ray Flare from Mrk 421
  Rosales de Leon, A. et al., arXiv e-prints parXiv:2101.01743 (2021) [LINK]
  
• The relentless variability of Mrk 421 from the TeV to the radio
  Arbet-Engels, Axel et al., arXiv e-prints parXiv:2101.10651 (2021) [LINK]
  
• Short-Timescale Variability of the Blazar Mrk 421 from AstroSat and Simultaneous Multi-Wavelength Observations
  Chatterjee, Ritaban et al., arXiv e-prints parXiv:2102.00919 (2021) [LINK]
  
• Correlations between gamma-ray luminosity and magnetization of the jet as well as relativistic electron injection power:cases for Mrk 421, 3C 454.3 and 3C 279
  Hu, Wen et al., arXiv e-prints parXiv:2102.07328 (2021) [LINK]
  
• Extreme HBL-like behavior of Markarian 421 and its two-zone photohadronic interpretation
  Sahu, Sarira et al., arXiv e-prints parXiv:2104.11999 (2021) [LINK]
  
• Kinetic powers of the relativistic jets in Mrk 421 and Mrk 501
  Deng, Xiao-Chun et al., MNRAS 504 p878-887 (2021) [LINK]
  
• Connecting steady emission and Very High Energy flaring states in blazars: the case of Mrk 421
  Dmytriiev, A. et al., arXiv e-prints parXiv:2105.12480 (2021) [LINK]
  
• Long-term spectra of the blazars Mrk 421 and Mrk 501 at TeV energies seen by HAWC
  Albert, A. et al., arXiv e-prints parXiv:2106.03946 (2021) [LINK]
  
• Investigation of the correlation patterns and the Compton dominance variability of Mrk 421 in 2017
  MAGIC Collaboration et al., arXiv e-prints parXiv:2106.05516 (2021) [LINK]
  
• Multi-wavelength study of Mrk 421 during a TeV flare
  Gokus, A. et al., arXiv e-prints parXiv:2108.02085 (2021) [LINK]
  
• Relentless multi-wavelength variability of Mrk 421 and Mrk 501
  Sliusar, Vitalii et al., arXiv e-prints parXiv:2108.08130 (2021) [LINK]
  
• GeV-radio correlation in Markarian 421
  Sliusar, Vitalii et al., arXiv e-prints parXiv:2108.08126 (2021) [LINK]
  
• Recent Results from VERITAS AGN Observations
  Benbow, Wystan on behalf of the VERITAS Collaboration, arXiv e-prints parXiv:2108.05460 (2021) [LINK]
  
• Confronting observations of VHE gamma-ray blazar flares with reconnection models
  Jormanainen, J. et al., arXiv e-prints parXiv:2109.08529 (2021) [LINK]
  
• X-ray spectra, light-curves and SEDs of blazars frequently observed by Swift
  Giommi, Paolo et al., MNRAS p (2021) [LINK]
  
• Understanding the X-ray spectral curvature of Mkn 421 using broadband AstroSat observations
  Hota, Jyotishree et al., arXiv e-prints parXiv:2110.03344 (2021) [LINK]
  
• An expanding one-zone model for studying blazars emission
  Boula, Stella S. and Mastichiadis, Apostolos, arXiv e-prints parXiv:2110.05325 (2021) [LINK]
  
• High-energy neutrinos from X-rays flares of blazars frequently observed by the Swift X-Ray Telescope
  Stathopoulos, S.I. et al., arXiv e-prints parXiv:2111.09320 (2021) [LINK]
  
• Detectability of large correlation length inflationary magnetic field with Cherenkov telescopes
  Korochkin, Alexander et al., arXiv e-prints parXiv:2111.10311 (2021) [LINK]
  
• Radio-gamma-ray response in blazars as signature of adiabatic blob expansion
  Tramacere, Andrea et al., arXiv e-prints parXiv:2112.03941 (2021) [LINK]
  
• Dual-high-frequency VLBI study of blazar-jet brightness-temperature gradients and collimation profiles
  Burd, P.R. et al., arXiv e-prints parXiv:2112.04403 (2021) [LINK]
  
• Relevance of VHE Blazar Spectra Models with Axion-Like Particles
  Li, Hai-Jun, arXiv e-prints parXiv:2112.14145 (2021) [LINK]
  
• Investigating Multiwavelength Lognormality with Simulations : Case of Mrk 421
  Chakraborty, Nachiketa, arXiv e-prints parXiv:2001.02458 (2020) [LINK]
  
• Unravelling the complex behavior of Mrk 421 with simultaneous X-ray and VHE observations during an extreme flaring activity in April 2013
  MAGIC collaboration et al., arXiv e-prints parXiv:2001.08678 (2020) [LINK]
  
• The Great Markarian 421 Flare of February 2010: Multiwavelength variability and correlation studies
  Abeysekara, A.U. et al., arXiv e-prints parXiv:2002.03567 (2020) [LINK]
  
• Gamma-ray Emission Properties of Four Bright Fermi-LAT AGNs: Implications on Emission Processes
  Kushwaha, Pankaj et al., arXiv e-prints parXiv:2003.01339 (2020) [LINK]
  
• Time dependent modeling of electron acceleration and cooling during blazar flares
  Dmytriiev, A. et al., arXiv e-prints parXiv:2003.07663 (2020) [LINK]
  
• Variations of the physical parameters of the blazar Mrk 421 based on the analysis of the spectral energy distributions
  Yamada, Yurika et al., arXiv e-prints parXiv:2003.08016 (2020) [LINK]
  
• Swift Observations of Mrk 421 in Selected Epochs. III. Extreme X-Ray Timing/Spectral Properties and Multiwavelength Lognormality during 2015 December-2018 April
  Kapanadze, B. et al., ApJS 247 p27 (2020) [LINK]
  
• Blazar variability power spectra from radio up to TeV photon energies: Mrk 421 and PKS 2155-304
  Goyal, Arti, arXiv e-prints parXiv:2004.02765 (2020) [LINK]
  
• Blazar Variability: A Study of Non-stationarity and the Flux-RMS Relation
  Bhattacharyya, Souradip et al., arXiv e-prints parXiv:2005.05230 (2020) [LINK]
  
• X-ray Flux and Spectral Variability of the TeV Blazars Mrk 421 and PKS 2155-304
  Gupta, Alok C., arXiv e-prints parXiv:2009.02263 (2020) [LINK]
  
• An Explanation for 13 consecutive days activities of Mrk 421
  Zheng, Y.G. et al., arXiv e-prints parXiv:2009.06152 (2020) [LINK]
  
• Establishing a particle distribution for multi-wavelength emission from BL Lac objects
  Xie, X.X. et al., arXiv e-prints parXiv:2009.06153 (2020) [LINK]
  
• Unfolding the X-ray Spectral Curvature of Mkn 421 for Further Clues
  Goswami, Pranjupriya et al., MNRAS p (2020) [LINK]
  
• An explanation about the flat radio spectrum for Mrk 421
  Xue, Rui and Wang, Ze-Rui, arXiv e-prints parXiv:2011.06439 (2020) [LINK]
  
• Fast magnetic reconnection structures in Poynting-flux dominated jets
  Kadowaki, Luis H. S et al., arXiv e-prints parXiv:2011.03634 (2020) [LINK]
  
• A time-dependent particle acceleration and emission model: understanding particle spectral evolution and blazar flares
  Zheng, Y.G. et al., MNRAS 499 p1188-1199 (2020) [LINK]
  
• Multiwavelength variability and correlation studies of Mrk 421 during historically low X-ray and gamma-ray activity in 2015-2016
  MAGIC Collaboration et al., arXiv e-prints parXiv:2012.01348 (2020) [LINK]
  
• Limits on axion-like particles from Mrk 421 with 4.5-years period observations by ARGO-YBJ and Fermi-LAT
  Li, Hai-Jun et al., arXiv e-prints parXiv:2008.09464 (2020) [LINK]
  
• Leptonic and Hadronic Radiative Processes in Supermassive-Black-Hole Jets
  Cerruti, Matteo, arXiv e-prints parXiv:2012.13302 (2020) [LINK]
  
• Studies of extragalactic background light with TeV BL Lacertae objects
  Longhua, Qin et al., MNRAS 499 p2662-2671 (2020) [LINK]
  
• Reconcilement of VHE gamma-ray/X-ray correlation studies in Mrk 421 and break-down at high fluxes
  Gonzalez, M.M. et al., arXiv e-prints p (2019) [LINK]
  
• The Accretion Disk-Jet Connection in Blazars
  Mukherjee, S. et al., MNRAS p (2019) [LINK]
  
• Probing an X-ray flare pattern in Mrk 421 induced by multiple stationary shocks: a solution to the bulk Lorentz factor crisis
  Hervet, O. et al., arXiv e-prints p (2019) [LINK]
  
• Enhanced Activity of Mrk 421 for an extended period over 30 days measured by HAWC
  Garcia-Gonzalez, J.A., Martinez, I. on behalf of the HAWC Collaboration, The Astronomer's Telegram 12683 p1 (2019) [LINK]
  
• Prospects for Detecting X-ray Polarization in Blazar Jets
  Liodakis, I. et al., arXiv e-prints parXiv:1906.01647 (2019) [LINK]
  
• Optical polarization properties of February 2010 outburst of the blazar Mrk 421
  Singh, K.K. et al., Ap&SS 364 p88 (2019) [LINK]
  
• Time-dependent spectral modelling of Markarian 421 during a violent outburst in 2010
  Banerjee, B. et al., MNRAS 487 p845-857 (2019) [LINK]
  
• On the radiation energy density in the jet of high-energy emitting BL Lac objects and its impact on their multi-messenger role
  Tavecchio, F. et al., arXiv e-prints parXiv:1906.02521 (2019) [LINK]
  
• Multi-TeV flaring in nearby High Energy Blazars: A photohadronic scenario
  Sahu, Sarira, arXiv e-prints parXiv:1907.01174 (2019) [LINK]
  
• Spectral analysis of the blazars Markarian 421 and Markarian 501 with the HAWC Gamma-Ray Observatory
  Coutino de Leon, S. et al., 36th International Cosmic Ray Conference (ICRC2019) 36 p654 (2019) [LINK]
  
• Anisotropic electron populations in BL Lac jets: consequences for the observed emission
  Tavecchio, F. and Sobacchi, E., arXiv e-prints parXiv:1908.02183 (2019) [LINK]
  
• 5.5 years multi-wavelength variability of Mrk 421: evidences of leptonic emission from the radio to TeV
  Sliusar, Vitalii et al., arXiv e-prints parXiv:1909.13106 (2019) [LINK]
  
• ANTARES search for high-energy neutrinos from TeV-emitting blazars, Markarian 421 and 501, in coincidence with HAWC gamma-ray flares
  Organokov, Mukharbek and Pradier, Thierry, arXiv e-prints parXiv:1911.04963 (2019) [LINK]
  
• Nature of gamma-ray variability in blazars
  Bhatta, Gopal and Dhital, Niraj, arXiv e-prints parXiv:1911.08198 (2019) [LINK]
  
• Study of long-term flux and photon Index distributions of blazars using RXTE observations
  Khatoon, Rukaiya et al., arXiv e-prints parXiv:1910.14352 (2019) [LINK]
  
• A survey of Active Galaxies with the HAWC Gamma-ray Observatory
  Carraminana, Alberto et al., arXiv e-prints parXiv:1908.06831 (2019) [LINK]
  
• X-Ray Intraday Variability of the TeV Blazar Mrk 421 with Suzaku
  Zhang, Zhongli et al., ApJ 884 p125 (2019) [LINK]
  
• Gamma-ray light curves for the BL Lac Mrk 421 using HAWC data derived with a new approach
  Garcia-Gonzalez, J.A. et al., arXiv e-prints parXiv:1908.09452 (2019) [LINK]
  
• FACT - Multi-wavelength analysis of more than 30 flares of Mrk 421
  Sliusar, V. et al., 36th International Cosmic Ray Conference (ICRC2019) 36 p796 (2019) [LINK]
  
• Multi-TeV flares from the nearest Blazar Markarian 421 and their origin
  Sahu, S. et al., ArXiv e-prints p (2018) [LINK]
  
• Exceptional Flare of Mrk 421 at TeV energies
  Biland, A. et al., The Astronomer's Telegram 11184 p1 (2018) [LINK]
  
• HAWC observation of Mrk421 reaching peak TeV flux in month-long enhanced activity
  Garcia-Gonzalez, J.A. et al., The Astronomer's Telegram 11194 p1 (2018) [LINK]
  
• Swift/BAT finds hard X-Ray flaring activity correlated with an ongoing TeV flare of Mrk421
  Kadler, M. and Krimm, H., The Astronomer's Telegram 11195 p1 (2018) [LINK]
  
• TACTIC detection of a strong TeV flare from Mrk 421
  Rannot, R.C., The Astronomer's Telegram 11199 p1 (2018) [LINK]
  
• Possible Accretion Disk Origin of the Emission Variability of a Blazar Jet
  Chatterjee, R. et al., ArXiv e-prints p (2018) [LINK]
  
• Blazar Spectra with Hard-sphere-like Acceleration of Electrons
  Asano, K. and Hayashida, M., ArXiv e-prints p (2018) [LINK]
  
• Multi-color optical monitoring of ten blazars from 2005 to 2011
  Meng, N. et al., ArXiv e-prints p (2018) [LINK]
  
• X-ray spectral variability of blazars using principal component analysis
  Gallant, D. et al., ArXiv e-prints p (2018) [LINK]
  
• The flux distribution of individual blazars as a key to understand the dynamics of particle acceleration
  Sinha, A. et al., ArXiv e-prints p (2018) [LINK]
  
• Influence of Energy-Dependent Particle Diffusion on the X-ray spectral curvature of MKN 421
  Goswami, P. et al., ArXiv e-prints p (2018) [LINK]
  
• X-ray intraday variability of the TeV blazar Mrk 421 with Chandra
  Aggrawal, V. et al., MNRAS 480 p4873-4883 (2018) [LINK]
  
• Statistical analysis on XMM-Newton X-ray flares of Mrk 421: distributions of peak flux and flaring time duration
  Yan, D. et al., ArXiv e-prints p (2018) [LINK]
  
• Study of short term enhanced TeV gamma-ray emission from Mrk 421 observed with TACTIC on December 28, 2014
  Singh, K.K. et al., Astroparticle Physics 103 p122-130 (2018) [LINK]
  
• Search for high-energy neutrino emission from Mrk 421 and Mrk 501 with the ANTARES neutrino telescope
  Organokov, M. and Pradier, T., ArXiv e-prints p (2018) [LINK]
  
• Systematic investigation of X-ray spectral variability of TeV blazars during flares in the RXTE era
  Wang, Y. et al., ArXiv e-prints p (2018) [LINK]
  
• Long-term optical monitoring of TeV emitting Blazars
  Nilsson, K. et al., ArXiv e-prints p (2018) [LINK]
  
• Probing the Jets of Blazars Using the Temporal Symmetry of Their Multi-Wavelength Outbursts
  Roy, N. et al., ArXiv e-prints p (2018) [LINK]
  
• Long-term optical monitoring of TeV emitting blazars. I. Data analysis
  Nilsson, K. et al., A&A 620 pA185 (2018) [LINK]
  
• Search for Magnetically Broadened Cascade Emission From Blazars with VERITAS
  VERITAS Collaboration et al., ArXiv e-prints p (2017) [LINK]
  
• Increased TeV gamma-ray activity from Mrk 421 on January 1-4
  Wood, J., The Astronomer's Telegram 9936 p1 (2017) [LINK]
  
• A time dependent approach to model X-ray and gamma-ray light curves of Mrk 421 observed during the flare in February 2010
  Singh, K. et al., ArXiv e-prints p (2017) [LINK]
  
• HAWC detection of further increase in TeV gamma-ray flux from Mrk 421
  Martinez, I., The Astronomer's Telegram 9946 p1 (2017) [LINK]
  
• Gamma-ray and Optical Oscillations of PKS 0716+71, MRK 421, and BL Lac
  Sandrinelli, A. et al., ArXiv e-prints p (2017) [LINK]
  
• Blazar Jets Perturbed by Magneto-Gravitational Stresses in Supermassive Binaries
  Cavaliere, A. et al., ArXiv e-prints p (2017) [LINK]
  
• Expected signatures from hadronic emission processes in the TeV spectra of BL Lac objects
  Zech, A. et al., ArXiv e-prints p (2017) [LINK]
  
• Daily monitoring of TeV gamma-ray emission from Mrk 421, Mrk 501, and the Crab Nebula with HAWC
  Albert, A. et al., ArXiv e-prints p (2017) [LINK]
  
• Black hole astrophysics with HAWC, the High Altitude Water Cherenkov gamma-ray observatory
  Alberto Carraminana for the HAWC Collaboration, ArXiv e-prints p (2017) [LINK]
  
• An Original Mechanism for the Acceleration of Ultra-High-Energy Cosmic Rays
  Caprioli, D., ArXiv e-prints p (2017) [LINK]
  
• X-ray Intraday Variability of Five TeV Blazars with NuSTAR
  Pandey A. et al., ArXiv e-prints p (2017) [LINK]
  
• On the origin of the hard X-Ray excess of high-synchrotron-peaked BL Lac object Mrk 421
  Chen, L., ArXiv e-prints p (2017) [LINK]
  
• Long-term optical polarization variability and multiwavelength analysis of Blazar Mrk 421
  Fraija, N. et al., ArXiv e-prints p (2017) [LINK]
  
• Highlights from the VERITAS AGN Observation Program
  Benbow, W. and the VERITAS Collaboration, ArXiv e-prints p (2017) [LINK]
  
• X-ray/gamma-ray flux correlations in the BL Lacs Mrk 421 and 501 using HAWC data
  Garcia-Gonzalez, J.A. et al., ArXiv e-prints p (2017) [LINK]
  
• Spectral analysis of Markarian 421 and Markarian 501 with HAWC
  Coutino de Leon, S. et al., ArXiv e-prints p (2017) [LINK]
  
• Dissecting the long-term emission behaviour of the BL Lac object Mrk 421
  Carnerero, M.I. et al., ArXiv e-prints p (2017) [LINK]
  
• The 2HWC HAWC Observatory Gamma-Ray Catalog
  Abeysekara, A.U. et al., ApJ 843 p40 (2017) [LINK]
  
• Gamma-ray Flux Distribution and Non-linear behavior of Four LAT Bright AGNs
  Kushwaha, P. et al., ArXiv e-prints p (2017) [LINK]
  
• Mrk 421 showing enhanced activity at TeV energies with two short bright outbursts
  Biland, A. et al., The Astronomer's Telegram 11077 p1 (2017) [LINK]
  
• Mrk 421 exceptionally bright at TeV energies
  Biland, A., The Astronomer's Telegram 11086 p1 (2017) [LINK]
  
• Tests of the Einstein Equivalence Principle using TeV Blazars
  Wei, J. J. et al., ArXiv e-prints p (2016) [LINK]
  
• Multi-band Variability Analysis of Mrk 421
  Li, H.Z. et al., ArXiv e-prints p (2016) [LINK]
  
• Particle diffusion and localized acceleration in inhomogeneous AGN jets - Part II: stochastic variation
  Chen, X. et al., ArXiv e-prints p (2016) [LINK]
  
• Time-dependent neutrino emission from Mrk 421 during flares and predictions for IceCube
  Petropoulou, M. et al., ArXiv e-prints p (2016) [LINK]
  
• Long-term study of Mkn 421 with the HAGAR Array of Telescopes
  Sinha, A. et al., ArXiv e-prints p (2016) [LINK]
  
• Long-term multi-wavelength variability and correlation study of Markarian 421 from 2007 to 2009
  MAGIC Collaboration et al., ArXiv e-prints p (2016) [LINK]
  
• Inverse Compton X-ray Emissions from TeV blazar Mrk421 during a Historical Low-Flux State Observed with NuSTAR
  Kataoka, J. and Stawarz, L., ArXiv e-prints p (2016) [LINK]
  
• Enhanced and increasing activity in gamma rays and X-rays from the HBL Mrk421
  Biland, A., The Astronomer's Telegram 9137 p1 (2016) [LINK]
  
• Testing one-zone synchrotron-self-Compton models with spectral energy distributions of Mrk 421
  Zhu, Q. et al., ArXiv e-prints p (2016) [LINK]
  
• First year results of the High Altitude Water Cherenkov observatory
  Carraminana, A. and for the HAWC Collaboration, ArXiv e-prints p (2016) [LINK]
  
• First Study of Combined Blazar Light Curves with FACT and HAWC
  Dorner, D. et al., ArXiv e-prints p (2016) [LINK]
  
• A search for spectral hysteresis and energy-dependent time lags from X-ray and TeV gamma-ray observations of Mrk 421
  Abeysekara, A.U. et al., ArXiv e-prints p (2016) [LINK]
  
• Parsec scale polarization properties of the TeV blazar Markarian 421
  Lico, R. et al., ArXiv e-prints p (2015) [LINK]
  
• Multi-TeV flaring from blazars: Markarian 421 a case study
  Sahu, S. et al., ArXiv e-prints p (2015) [LINK]
  
• Could the Wein fireball be associated to the ''orphan'' TeV flares ?
  Fraija, N., ArXiv e-prints p (2015) [LINK]
  
• A combined radio and GeV gamma-ray view of the 2012 and 2013 flares of Mrk 421
  Hovatta, T. et al., ArXiv e-prints p (2015) [LINK]
  
• The 2009 multiwavelength campaign on Mrk 421: Variability and correlation studies
  MAGIC Collaboration et al., ArXiv e-prints p (2015) [LINK]
  
• Synchrotron Self-Compton Emission by Relativistic Electrons under Stochastic Acceleration: Application to Mrk 421 and Mrk 501
  Kakuwa, J. et al., ArXiv e-prints p (2015) [LINK]
  
• An emergence of new polarized emission region in blazar Mrk 421 associated with X-ray flare
  Itoh, R. et al., ArXiv e-prints p (2015) [LINK]
  
• Gamma-ray light curve and VLBI polarization connection in Mrk 421
  Giroletti, M. et al., ArXiv e-prints p (2015) [LINK]
  
• Hadronic flares and associated neutrinos for Markarian 421
  Marinelli, A. et al., 313 p177-178 (2015) [LINK]
  
• Study of underlying particle spectrum during huge X-ray flare of Mkn 421 in April 2013
  Sinha, A. et al., ArXiv e-prints p (2015) [LINK]
  
• Discovery of a Wandering Radio Jet Base after a Large X-Ray Flare in the Blazar Markarian 421
  Niinuma, K. et al., ApJ 807 pL14 (2015) [LINK]
  
• VHE gamma-ray/X-ray correlation studies in Mrk 421 down to the quiescent state
  Patricelli, B. et al., ArXiv e-prints p (2015) [LINK]
  
• Violent Hard X-ray Variability of Mrk 421 Observed by NuSTAR in 2013 April
  Paliya, V.S. et al., ArXiv e-prints p (2015) [LINK]
  
• Flaring activity of Mrk 421 in 2012 and 2013: orphan flare and multiwavelength analysis
  Fraija, N. et al., ArXiv e-prints p (2015) [LINK]
  
• Search for TeV Gamma-Ray Emission from Point-like Sources in the Inner Galactic Plane with a Partial Configuration of the HAWC Observatory
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• Highlights from the High Altitude Water Cherenkov Observatory
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