GCN Circulars
GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search
To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.
Lucene Examples (click to copy):
subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"
864 results found.
- IceCube-250416A: Upper limits from a search for additional neutrino events in IceCube
- GRB 250331C: Swift/UVOT Upper Limits
- IceCube-250330A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-250309A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-250302A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-Cascade 250215A: Upper limits from a search for additional neutrino events in IceCube
- LIGO/Virgo/KAGRA S250206dm: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- GECAM-A detection of a bright burst from SGR 1E1841-045
- Konus-Wind detection of a bright burst from SGR 1E1841-045 on 2025 January 23
- IPN triangulation of a bright burst from SGR 1E1841-045
- GRB 250116A: GECAM-B detection of a long burst
- IceCube-250102A: Upper limits from a search for additional neutrino events in IceCube
- Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
- GRB 241130A: EIRSAT-1 GMOD Detection
- IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
- SVOM/GRM observation of GRB 241126B or a short burst from magnetar
- SVOM/GRM detection of a short burst from SGR 1830
- GECAM detection of a short burst from SGR 1830
- LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
- EP241113a: Swift XRT weak detection
- IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
- SVOM/GRM detection of a short burst from SGR 1E1841-045
- INTEGRAL detection of a burst from 1E 1841-045
- EP241107a: EP on-board trigger and autonomous follow-up observation
- EP241025a (GRB 241025A): EP observations update
- GRB241017A: TOO Observations by SVOM/MXT
- IceCube-241006A: Upper limits from a search for additional neutrino events in IceCube
- SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
- Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
- GRB 240914A : An intermediate duration GRB located on-board by SVOM/ECLAIRs.
- SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
- SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
- SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
- GRB 240824A: Swift/UVOT Upper Limits
- SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
- SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
- GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
- Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
- Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
- Trigger 1249653: Swift detection of SGR 1E 1841-045 / Kes 73
- IceCube-Cascade 240518A: Upper limits from a search for additional neutrino events in IceCube
- LIGO/Virgo S240422ed: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- IceCube-Cascade 240416A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-240412A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-240327A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-240229A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-240204A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-240123A: Upper limits from a search for additional neutrino events in IceCube
- IPN triangulation of GRB 240112A (long)
- GRB 240112A: GECAM detection of a burst
- GRB 240106A: Glowbug gamma-ray detection
- IceCube-240105A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-231211A: Upper limits from a search for additional neutrino events in IceCube
- GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
- GECAM-B observation of a short burst from SGR J1555-5402
- SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
- Fermi GRB 231108A: Global MASTER-Net observations report
- LIGO/Virgo/KAGRA S231014r: Identification of a GW compact binary merger candidate
- LIGO/Virgo S230802aq: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230725A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230708A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230707B: Upper limits from a search for additional neutrino events in IceCube
- LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- IceCube-Cascade 230610A: Upper limits from a search for additional neutrino events in IceCube
- LIGO/Virgo/KAGRA S230609u: Identification of a GW compact binary merger candidate
- LIGO/Virgo/KAGRA S230529ay: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- LIGO/Virgo/KAGRA S230518h: Upper limits from Glowbug gamma-ray observations
- LIGO/Virgo S230518h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
- IceCube-Cascade 230511A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-Cascade 230430A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230416A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230405A: Upper limits from a search for additional neutrino events in IceCube
- SGR 1806-20: Correction to GCN 33494
- INTEGRAL detection of a burst from SGR 1806-200
- VZLUSAT-2 detection of SGR 1806-20
- GRB 230307A: soft X-ray detection with LEIA
- Trigger 1159327: Swift detection of SGR1806-20
- GRB 230307A: GECAM detection of an extremely bright burst
- IceCube-230220A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230201A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-230122A: Upper limits from a search for additional neutrino events in IceCube
- Fermi-LAT gamma-ray observations of IceCube-230112A
- IceCube-221229A: Upper limits from a search for additional neutrino events in IceCube
- Fermi-LAT gamma-ray observations of IceCube-221223A
- IceCube-221216A: Upper limits from a search for additional neutrino events in IceCube
- Konus-Wind detection of a burst from SGR 1935+2154 on 2022 December 13
- IceCube-221124A: Upper limits from a search for additional neutrino events in IceCube
- Konus-Wind detection of a burst from SGR 1935+2154 on 2022 November 9
- Fermi-GBM Observations of High Bursting Activity from SGR J1935+2154
- IceCube-221104A: Upper limits from a search for additional neutrino events in IceCube
- SGR 1935+2154: AstroSat CZTI Detections
- Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
- SGR 1935+21542: VZLUSAT-2 and GRBAlpha joint detection
- AGILE detection of a burst from SGR J1935+2154 reported by VZLUSAT-2
- SGR 1935+2154: Bursting activity detected by VZLUSAT-2
- AGILE detection of the 2022 October 17 burst from SGR J1935+2154 reported by Konus-Wind
- SGR 1935+2154: Detection by GRBAlpha
- Konus-Wind detection of a burst from SGR 1935+2154 on 2022 October 17
- AGILE detection of short X-ray flaring activity contemporary to SGR J1935+2154 reported bursts