activity
20192026
most citedPeriodic Gamma-ray Modulation of the blazar PG 1553+113 Confirmed by Fermi-LAT and Multi-wavelength Observations

19 citations · 49 across the 17 of their papers we have counts for

collaborators

19 papers

astro-ph.GA2026

Profile Analysis of the Multiwavelength 2.1-year Oscillations of PG 1553+113

P. Peñil, N. Torres-Albà, A. Rico +5

We investigate the morphology of the oscillation profiles of the blazar PG~1553+113 in relation to its well-known 2.1 yr periodicity. We identify individual cycles in the …

astro-ph.HE2026

Gamma-Ray Periodicity in Jetted AGN: Revisiting Periodicity Candidates with >17 years of Fermi-LAT Data

P. Peñil, A. Rico, A. Domínguez +3

We reanalyze previously reported gamma-ray periodicity candidates in jetted active galactic nuclei using more than 17 years of Fermi-LAT observations. The updated data provide a ro…

astro-ph.HE2026

Testing X-ray Periodicity and Long-Term Trend in PG 1553+113 via Targeted Swift-XRT Monitoring

P. Peñil, N. Torres-Albà, L. Marcotulli +5

PG~1553+113 is the blazar with the most-significantly detected periodic patter in its multiwavelength (MWL) emission, making it one of the most promising candidates for hosting a s…

astro-ph.HE2025

Gamma-ray Time Delay and Magnification Ratio in the Gravitationally-Lensed Blazar PKS 1830-211

S. Buson, M. De Toma, S. Larsson +7

We present the characterization of macrolensing properties of the gravitationally lensed system PKS 1830-211, utilizing data from the Fermi Large Area Telescope. While at gamma-ray…

astro-ph.HE2025

Distortions in Periodicity Analysis of Blazars II: The Impact of Gaps

P. Peñil, N. Torres-Albà, A. Rico +4

Time series analysis is fundamental to characterizing the variability inherent in multi-wavelength emissions from blazars. However, a major observational challenge lies in the need…

astro-ph.HE2025

Extensive Analysis of gamma-Ray Periodicity in Jetted AGN from the 4FGL Catalog Using Fermi-LAT Observations

P. Peñil, A. Domínguez, S. Buson +3

The quest to uncover periodic patterns within the -ray emissions of jetted active galactic nuclei (AGN) has recently emerged as a focal point in astrophysics. One of the primary…

astro-ph.HE2025★ 4 cited

Transient QPOs of Fermi-LAT blazars under the Curved Jet Model

P. Penil, J. Otero-Santos, A. Banerjee +4

This study explores transient quasi-periodic oscillations (QPOs) in the -ray emission of two blazars, PMN J05314827 and PKS 1502+106, using over a decade of Fermi Large Area…

astro-ph.HE2025

Transient QPOs of Fermi-LAT blazars with Linearly Multiplicative Oscillations

P. Penil, J. Otero-Santos, A. Circiello +5

We present a study on the detection and characterization of transient quasi-periodic oscillations (QPOs) in the -ray emission of blazars 4C +31.03, MG1 J123931+0443, and PKS 162…

astro-ph.HE2025★ 2 cited

Puzzling Variation of Gamma Rays from the Sun over the Solar Cycle Revealed with Fermi-LAT

A. Acharyya, A. Adelfio, M. Ajello +100

The steady-state gamma-ray emission from the Sun is thought to consist of two emission components due to interactions with Galactic cosmic rays: (1) a hadronic disk component, and…

astro-ph.HE2025

Search for Kink Events in Variable Fermi-LAT Blazars

P. Peñil, H. Zhang, J. Otero-Santos +10

This study explores the detection of Quasi-Periodic Oscillations (QPOs) in blazars as a method to identify kink events within their jets, utilizing both -ray and polarized light…

astro-ph.HE2025

Fermi detection of gamma-ray Emission from the Hot Coronae of Radio-quiet Active Galactic Nuclei

Jun-Rong Liu, Jian-Min Wang, Fermi-LAT Collaboration

Relativistic jets around supermassive black holes (SMBHs) are well-known powerful -ray emitters. In absence of the jets in radio-quiet active galactic nuclei (AGNs), how the SMB…

astro-ph.HE2025★ 19 cited

Periodic Gamma-ray Modulation of the blazar PG 1553+113 Confirmed by Fermi-LAT and Multi-wavelength Observations

S. Abdollahi, L. Baldini, G. Barbiellini +98

A 2.1-year periodic oscillation of the gamma-ray flux from the blazar PG 1553+113 has previously been tentatively identified in almost 7 year of data from the Fermi Large Area Tele…

astro-ph.HE2025

Systematic Search for Long-Term Trends in Fermi-LAT Jetted Active Galactic Nuclei

P. Penil, A. Domínguez, S. Buson +3

Jetted Active Galactic Nuclei (AGN) exhibit variability across a wide range of time scales. Traditionally, this variability can often be modeled well as a stochastic process. Howev…

astro-ph.HE2024★ 13 cited

Singular Spectrum Analysis of Fermi-LAT Blazar Light Curves: A Systematic Search for Periodicity and Trends in the Time Domain

Alba Rico, A. Domínguez, P. Peñil +4

A majority of blazars exhibit variable emission across the entire electromagnetic spectrum, observed over various time scales. In particular, discernible periodic patterns are dete…

astro-ph.HE2024

GRB 221009A: the B.O.A.T Burst that Shines in Gamma Rays

M. Axelsson, M. Ajello, M. Arimoto +151

We present a complete analysis of Fermi Large Area Telescope (LAT) data of GRB 221009A, the brightest Gamma-Ray Burst (GRB) ever detected. The burst emission above 30 MeV detected…

astro-ph.HE2024

Multiwavelength Variability Analysis of Fermi-LAT Blazars

P. Peñil, J. Otero-Santos, M. Ajello +6

Blazars present highly variable -ray emission. This variability, which can range from a few minutes to several years, is also observed at other wavelengths across the entire ele…

astro-ph.HE2023★ 1 cited

Multiwavelength Analysis of Fermi-LAT Blazars with High-Significance Periodicity: Detection of a Long-Term Rising Emission in PG 1553+113

P. Peñil, J. R. Westernacher-Schneider, M. Ajello +6

Blazars display variable emission across the entire electromagnetic spectrum, with timescales that can range from a few minutes to several years. Our recent work has shown that a s…

astro-ph.HE2019★ 10 cited

Bright gamma-ray flares observed in GRB131108A

Donggeun Tak, Z. Lucas Uhm, Bing Zhang

GRB 131108A is a bright long Gamma-Ray Burst (GRB) detected by the Large Area Telescope and the Gamma-ray Burst Monitor on board the Fermi Gamma-ray Space Telescope. Dedicated temp…

astro-ph.HE2019

A Search for Cosmic-ray Proton Anisotropy with the Fermi Large Area Telescope

LAT Collaboration

The Fermi Large Area Telescope (LAT) has amassed a large data set of primary cosmic-ray protons throughout its mission. The LAT's wide field of view and full-sky survey capabilitie…