arXiv subjects

Fabian Schussler

Publications and source records attributed to Fabian Schussler.

4 recordsLinked to original sources

arXiv2026

GRINTA: a new Probe of the Dynamic Universe

Recent observations of the transient sky at all wavelengths are increasingly revealing the importance of the multi-messenger and multi-wavelength approach. The GRINTA (Gamma-Ray INternational Transient Array Observatory) mission, proposed for launch around the middle of the next decade, is conceived as a small mission with good sensitivity, excellent angular resolution and fast follow-up capability for studying transient sources at timescales from ms to hours, at the same time ensuring optimal integration with multi-messenger networks. The GRINTA mission will carry two complementary payloads to cover in total the 5 keV-10 MeV band, that will detect and localise gamma-ray bursts covering $\sim$ half of the sky and will be able to perform imaging surveys with sub-arcmin resolution. GRINTA will operate in synergy with the most powerful electromagnetic, gravitational wave and neutrino observatories foreseen to be operational after 2035.

astro-ph.IM↗

arXiv2026

Astro-COLIBRI: An Innovative Platform for Real-Time Multi-Messenger Astrophysics

The discovery of transient phenomena, such as supernovae, novae, Fast Radio Bursts (FRBs), Gamma-Ray Bursts (GRBs), and stellar flares, together with the emergence of new cosmic messengers like high-energy neutrinos and Gravitational Waves (GWs), has revolutionized astrophysics in recent years. To fully exploit the scientific potential of multi-messenger and multi-wavelength follow-up observations, as well as serendipitous detections, researchers need a tool capable of rapidly compiling and contextualizing essential information for every new event. We present Astro-COLIBRI, an advanced platform designed to meet this challenge. Astro-COLIBRI is a comprehensive platform that combines a public RESTful API, real-time databases, a cloud-based alert system, and user-friendly interfaces including a website and mobile app for iOS and Android. It ingests alerts from multiple sources in real time, applies user-defined filters, and situates each event within its multi-messenger and multi-wavelength context. The platform provides clear data visualization, concise summaries of key event properties, and evaluations of observing conditions across a wide network of observatories worldwide. We here detail the architecture of Astro-COLIBRI, from the data pipelines that manage real-time alert ingestion and processing to the design of the RESTful API, which enables seamless integration with other astronomical software and services.

astro-ph.IM↗

arXiv2025

The H.E.S.S. Gravitational Wave and Gamma-Ray Burst Follow-Up Programs

Multi-wavelength and multi-messenger astrophysics have experienced rapid growth over the past decade, seeking a complete picture of different cosmic phenomena. Transient sources, in particular, benefit from the input of multi-messenger observations, offering complementary perspectives on the same event while maximizing the detection probability of a rapidly fading signal. In this context, Gravitational Wave (GW) detections serve as perfect triggers for potential counterpart detections. Notably, a GW alert could be associated with a Gamma-Ray Burst (GRB), jetted cataclysmic events produced either by the collision of a binary neutron star system or a core-collapse supernova. These sources also radiate across the electromagnetic spectrum, allowing detection by X- and gamma-ray instruments aboard various satellites and thus enabling multi-wavelength triggering opportunities. The strong interest in minimizing reaction time to capture the full-time evolution of the emission, together with the often challenging localization uncertainties of the alerts, underscores the need for rapid and well-coordinated follow-up programs such as the one developed by the H.E.S.S. Collaboration. This contribution will give an overview of the transient follow-up strategy carried out by the H.E.S.S. Collaboration, from the external alert trigger and the automatic reaction of the observatory to the various analysis steps of the obtained observations. To illustrate this comprehensive strategy, we will show two examples of follow-up observations of both GRBs and GWs, highlighting key results and challenges in the search for an associated high-energy gamma-ray emission.

astro-ph.HE↗

arXiv2016

The Cherenkov Telescope Array On-Site integral sensitivity: observing the Crab

The Cherenkov Telescope Array (CTA) is the future large observatory in the very high energy (VHE) domain. Operating from 20 GeV to 300 TeV, it will be composed of tens of Imaging Air Cherenkov Telescopes (IACTs) displaced in a large area of a few square kilometers in both the southern and northern hemispheres. The CTA/DATA On-Site Analysis (OSA) is the system devoted to the development of dedicated pipelines and algorithms to be used at the CTA site for the reconstruction, data quality monitoring, science monitoring and realtime science alerting during observations. The OSA integral sensitivity is computed here for the most studied source at Gamma-rays, the Crab Nebula, for a set of exposures ranging from 1000 seconds to 50 hours, using the full CTA Southern array. The reason for the Crab Nebula selection as the first example of OSA integral sensitivity is twofold: (i) this source is characterized by a broad spectrum covering the entire CTA energy range; (ii) it represents, at the time of writing, the standard candle in VHE and it is often used as unit for the IACTs sensitivity. The effect of different Crab Nebula emission models on the CTA integral sensitivity is evaluated, to emphasize the need for representative spectra of the CTA science targets in the evaluation of the OSA use cases. Using the most complete model as input to the OSA integral sensitivity, we obtain a significant detection of the Crab nebula (about 10% of flux) even for a 1000 second exposure, for an energy threshold less than 10 TeV.

astro-ph.IM↗