Camelidae on the BOAT: observation of a second spectral component in GRB 221009A

Camelidae on the BOAT: observation of a second spectral component in GRB 221009A | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Camelidae on the BOAT: observation of a second spectral component in GRB 221009A Biswajit Banerjee, Samanta Macera, Alessio De Santis, Alessio Mei, and 7 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4491618/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Observing and understanding the origin of the very-high-energy (VHE) spectral component in gamma-ray bursts (GRBs) has been challenging because of the lack of sensitivity in MeV-GeV observations, so far. The majestic GRB 221009A, known as the brightest of all times (BOAT), offers a unique opportunity to identify spectral components during the prompt and early afterglow phases and probe their origin. Analyzing simultaneous observations spanning from keV to TeV energies, we identified two distinct spectral components during the initial 20 minutes of the burst. The second spectral component peaks between 10 − 300 GeV, and the bolometric fluence (10 MeV-10 TeV) is estimated to be greater than 2×10 −3 erg/ cm 2 . Performing broad-band spectral modeling, we provide constraints on the magnetic field and the energies of electrons accelerated in the external relativistic shock. We interpret the VHE component as an afterglow emission that is affected by luminous prompt MeV radiation at early times. Physical sciences/Astronomy and planetary science/Astronomy and astrophysics/High-energy astrophysics Physical sciences/Astronomy and planetary science/Astronomy and astrophysics/Transient astrophysical phenomena high energy astrophysics gamma rays: bursts gamma rays: observations methods: observational Full Text Additional Declarations There is NO Competing Interest. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4491618","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":326142692,"identity":"2adfcb3c-dd5f-480c-8651-a10137b1c20b","order_by":0,"name":"Biswajit Banerjee","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABFklEQVRIiWNgGAWjYBACA2YQySPBwCAB5rMxMLA3gMQZeAhpkUBo4TkA0YJLjwGUhmkBMRMgNC4t5uzszyR+yFjUMUg3P3vwcQ+fHL/k88sffxQwyNjj0GLZzGMm2QNymMwxc8MZz9iMJWfnlEnz4HPYYR62GzxgvySYSfMcYEvccDsnjRmvXw6zP7v5B6wl/Zv0nwNs9ftvnkn++AOvFgaz2xBbcsykGQ6wJRhIsB+QwOcwoF/Mf8vwSEi2yZwpk+w5wGY440wOG9AvEjzgwMYWYvzHHxu+7anj55du3ybx48Axef72448//vhjYw+OUlyAsQcchyBwDIh5QJElgUc9CPyAs2qAmP0BAeWjYBSMglEwwgAAtKVLKpA3PjcAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0002-8008-2485","institution":"Gran Sasso Science Institute","correspondingAuthor":true,"prefix":"","firstName":"Biswajit","middleName":"","lastName":"Banerjee","suffix":""},{"id":326142693,"identity":"4c5667d9-bd98-4578-bf09-acd00b369e73","order_by":1,"name":"Samanta Macera","email":"","orcid":"","institution":"Gran Sasso Science Institute","correspondingAuthor":false,"prefix":"","firstName":"Samanta","middleName":"","lastName":"Macera","suffix":""},{"id":326142694,"identity":"bcdf0456-3197-47b9-a44b-09f8e9893506","order_by":2,"name":"Alessio De Santis","email":"","orcid":"","institution":"Gran Sasso Science Institute","correspondingAuthor":false,"prefix":"","firstName":"Alessio","middleName":"","lastName":"De Santis","suffix":""},{"id":326142695,"identity":"6e56440c-0e3b-42e6-b17b-6c76b28348ac","order_by":3,"name":"Alessio Mei","email":"","orcid":"","institution":"Gran Sasso Science Institute","correspondingAuthor":false,"prefix":"","firstName":"Alessio","middleName":"","lastName":"Mei","suffix":""},{"id":326142696,"identity":"a33b9f53-397d-476b-8883-ccb67ada61b9","order_by":4,"name":"Jacopo Tissino","email":"","orcid":"","institution":"Gran Sasso Science Institute","correspondingAuthor":false,"prefix":"","firstName":"Jacopo","middleName":"","lastName":"Tissino","suffix":""},{"id":326142697,"identity":"d2bf4a40-d7cc-4df9-af8d-cace1dc43990","order_by":5,"name":"Gor Oganesyan","email":"","orcid":"https://orcid.org/0000-0001-9765-1552","institution":"Gran Sasso Science Institute, Viale F. 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