Detection prospects of very and ultra high-energy gamma rays from extended sources with ASTRI, CTA, and LHAASO

Abstract

Context. The recent discovery of several ultra high-energy gamma-ray emitters in our Galaxy represents a significant advancement towards the characterisation of its most powerful accelerators. Nonetheless, in order to unambiguously locate the regions where the highest energy particles are produced and understand the responsible physical mechanisms, detailed spectral and morphological studies are required, especially given that most of the observed sources were found to be significantly extended. Aims. In these regards, pointing observations with the next-generation Imaging Atmospheric Cherenkov Telescopes, such as the Cherenkov Telescope Array (CTA) Observatory and the ASTRI Mini-Array (ASTRI), are expected to provide significant improvements. Here we aim to identify the most promising sources to target in future observations. Methods. For this purpose, we performed a comparative analysis of the expected performance of ASTRI and CTA, computing their differential sensitivities towards extended sources, and further explored their capabilities with respect to specific case studies, including follow-ups of existing gamma-ray source catalogues. Results. We find that almost all of the sources thus far detected by LHAASO-WCDA and in the H.E.S.S. Galactic Plane Survey will be in the reach of ASTRI and CTA with about 300 and 50 hours of exposure, respectively. For the highest energy emitters detected by LHAASO-KM2A, in turn, we provide a list of the most promising objects that would require further investigation. We additionally examined specific classes of sources in order to identify potentially detectable gamma-ray emitters, such as passive molecular clouds (i.e. illuminated by the cosmic-ray sea) and pulsars surrounded by a halo of runaway particles.

Accepted for publication in A&A

References in corpus (29)

• Extended gamma-ray sources around pulsars constrain the origin of the positron flux at Earth
• Physical properties of molecular clouds for the entire Milky Way disk
• Background Modelling in Very-High-Energy gamma-ray Astronomy
• The First LHAASO Catalog of Gamma-Ray Sources
• The observation of the Crab Nebula with LHAASO-KM2A for the performance study
• Extended Very-High-Energy Gamma-Ray Emission Surrounding PSR J0622 + 3749 Observed by LHAASO-KM2A
• Searching for galactic cosmic ray pevatrons with multi-TeV gamma rays and neutrinos
• Gamma-ray halos around pulsars as the key to understanding cosmic ray transport in the Galaxy
• Acceleration and transport of relativistic electrons in the jets of the microquasar SS 433
• The ASTRI Mini-Array of Cherenkov Telescopes at the Observatorio del Teide
• ASTRI Mini-Array Core Science at the Observatorio del Teide
• On the potential of bright, young pulsars to power ultra-high gamma-ray sources
• Does the Geminga, Monogem and PSR J0622+3749 $\gamma$-ray halos imply slow diffusion around pulsars?
• Validation of open-source science tools and background model construction in $\gamma$-ray astronomy
• Cosmic-Ray Events as Background in Imaging Atmospheric Cherenkov Telescopes
• Detection of extended gamma-ray emission around the Geminga pulsar with H.E.S.S
• Anisotropic diffusion cannot explain TeV halo observations
• Probing the Cosmic Ray density in the inner Galaxy
• Evidence of 100 TeV $\gamma$-ray emission from HESS J1702-420: A new PeVatron candidate
• Spectral signatures of PeVatrons
• HESS J1809$-$193: a halo of escaped electrons around a pulsar wind nebula?
• Evidence of Cosmic-Ray Excess from Local Giant Molecular Clouds
• HAWC Detection of a TeV Halo Candidate Surrounding a Radio-quiet pulsar
• Using Interstellar Clouds to Search for Galactic PeVatrons: Gamma-ray Signatures from Supernova Remnants
• Ultrahigh-energy Gamma-Ray Radiation from the Crab Pulsar Wind Nebula
• Probing the galactic cosmic-ray density with current and future $\gamma$-ray instruments
• Mass and wind luminosity of young Galactic open clusters in Gaia DR2
• Multiwavelength constraints on the unidentified Galactic TeV sources HESS J1427$-$608, HESS J1458$-$608, and new VHE $\gamma$-ray source candidates
• A study of the interstellar medium towards the unidentified dark TeV $\gamma$-ray sources HESS J1614-518 and HESS J1616-508

Cited by in corpus (5)

• The environment of TeV halo progenitors
• Revisiting the propagation of highly-energetic gamma rays in the Galaxy
• Very high-energy gamma-ray and neutrino emission from hadronic interaction in compact binary millisecond pulsars
• Search for TeV emission from spider millisecond pulsars with HAWC
• Interpreting the LHAASO Galactic diffuse emission data