Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher.
                                            Some full text articles may not yet be available without a charge during the embargo (administrative interval).
                                        
                                        
                                        
                                            
                                                
                                             What is a DOI Number?
                                        
                                    
                                
Some links on this page may take you to non-federal websites. Their policies may differ from this site.
- 
            Free, publicly-accessible full text available May 1, 2026
- 
            Abstract The HAWC Observatory collected 6 yr of extensive data, providing an ideal platform for long-term monitoring of blazars in the very high energy (VHE) band, without bias toward specific flux states. HAWC continuously monitors blazar activity at TeV energies, focusing on sources with a redshift ofz≤ 0.3, based on the Third Fermi-LAT Catalog of High-Energy sources. We specifically focused our analysis on Mrk 421 and Mrk 501, as they are the brightest blazars observed by the HAWC Observatory. With a data set of 2143 days, this work significantly extends the monitoring previously published, which was based on 511 days of observation. By utilizing HAWC data for the VHEγ-ray emission in the 300 GeV–100 TeV energy range, in conjunction with Swift-XRT data for the 0.3–10 keV X-ray emission, we aim to explore potential correlations between these two bands. For Mrk 501, we found evidence of a long-term correlation. Additionally, we identified a period in the light curve where the flux was very low for more than 2 yr. On the other hand, our analysis of Mrk 421 measured a strong linear correlation for quasi-simultaneous observations collected by HAWC and Swift-XRT. This result is consistent with a linear dependence and a multiple-zone synchrotron self-Compton model to explain the X-ray andγ-ray emission. Finally, as suggested by previous findings, we confirm a harder-when-brighter behavior in the spectral evolution of the flux properties for Mrk 421. These findings contribute to the understanding of blazar emissions and their underlying mechanisms.more » « lessFree, publicly-accessible full text available February 5, 2026
- 
            Free, publicly-accessible full text available September 1, 2026
- 
            Free, publicly-accessible full text available September 1, 2026
- 
            Free, publicly-accessible full text available September 1, 2026
- 
            Observation of nuclear modification of energy-energy correlators inside jets in heavy ion collisionsFree, publicly-accessible full text available July 1, 2026
- 
            Free, publicly-accessible full text available July 1, 2026
- 
            Free, publicly-accessible full text available July 1, 2026
- 
            Free, publicly-accessible full text available June 1, 2026
- 
            Free, publicly-accessible full text available May 1, 2026
 An official website of the United States government
An official website of the United States government 
				
			 
					 
					
