ATTENZIONE! IL REPOSITORY E’ APERTO ESCLUSIVAMENTE ALL’IMMISSIONE DEI RAPPORTI TECNICI (COLLEZIONE 4.01). NON E’ POSSIBILE INSERIRE PRODOTTI IN TUTTE LE ALTRE COLLEZIONI, A CAUSA DI PROBLEMI TECNICI. THE REPOSITORY IS OPEN EXCLUSIVELY FOR THE SUBMISSION OF TECHNICAL REPORTS (COLLECTION 4.01). SUBMISSIONS TO ALL OTHER COLLECTIONS ARE TEMPORARILY UNAVAILABLE, DUE TO TECHNICAL ISSUES.
 

Exploring the connection between radio and GeV-TeV gamma-ray emission in the 1FHL and 2FHL AGN samples

Journal
Date Issued
2017
Author(s)
•
•
•
Costamante, L.
•
Pavlidou, V.
•
•
DOI
Abstract
The Fermi Large Area Telescope (LAT) revealed that blazars, representing the most extreme radio-loud active galactic nuclei (AGN) population, dominate the census of the gamma-ray sky, and a significant correlation was found between radio and gamma-ray emission in the 0.1-100 GeV energy range. However, the possible connection between radio and very high energy (VHE, E>0.1 TeV) emission still remains elusive, owing to the lack of a homogeneous coverage of the VHE sky. The main goal of this work is to quantify and assess the significance of a possible connection between the radio emission on parsec scale measured by the very long baseline interferometry (VLBI) and GeV-TeV gamma-ray emission in blazars, which is a central issue for understanding the blazar physics and the emission processes. We investigate the radio VLBI and high energy gamma-ray emission by using two large and unbiased AGN samples extracted from the first and second Fermi-LAT catalogs of hard gamma-ray sources detected above 10 GeV (1FHL) and 50 GeV (2FHL). For comparison, we perform the same correlation analysis by using the 0.1-300 GeV gamma-ray energy flux provided by the third Fermi-LAT source catalog. We find that the correlation strength and significance depend on the gamma-ray energy range with a different behavior among the blazar sub-classes. Overall, the radio and gamma-ray emission above 10 GeV turns out to be uncorrelated for the full samples and for all of the blazar sub-classes with the exception of high synchrotron peaked (HSP) objects, which show a strong and significant correlation. On the contrary, when 0.1-300 GeV gamma-ray energies are considered, a strong and significant correlation is found for the full blazar sample as well as for all of the blazar sub-classes. We interpret and explain this correlation behavior within the framework of the blazar spectral energy distribution properties.
Volume
606
Start page
A138
Uri
Url
Issn Identifier
0004-6361
Ads BibCode
2017A&A...606A.138L
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

aa31116-17.pdf

Description
Pdf editoriale
Size

500.51 KB

Format

Adobe PDF

Checksum (MD5)

743f8ba6888be659fd32c4bba4f25307

Loading...
Thumbnail Image
Name

1708.06201.pdf

Description
postprint
Size

450.07 KB

Format

Adobe PDF

Checksum (MD5)

c2e0b71a0dbc7c5d5220e5971d6dc9c1