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.
Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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.
Advanced Search Examples (click to copy):
subject:"Swift"body:"GRB"submitter:"Judith Racusin"21392 results found.
- Swift GRB230720.30: Global MASTER-Net observations report
- IPN triangulation of GRB 230715D
- Swift Trigger 1180063 is not a GRB
- Swift Trigger 1180060 is not a GRB
- Swift Trigger 1180055 is not a GRB
- IPN triangulation of GRB 230712C (short)
- IPN triangulation of GRB 230712A (short)
- IceCube-230707A : MAXI upper limit and NICER follow-up observation of Swift J1753.5-0127
- GRB 230709C: Swift/BAT-GUANO detection of a short burst outside the coded FOV
- IceCube-230708A: Upper limits from Swift/BAT-GUANO
- GRB 230707A: Swift/BAT-GUANO position correction
- GRB 230707B: Fermi GBM Observation
- IceCube-230707A: No candidates detected by Swift-XRT
- Swift Trigger 1178410 is not an astrophysical event
- GRB 230707B: CALET Gamma-Ray Burst Monitor detection
- Swift Trigger 1178410: possible GRB 230709A
- GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
- GRB 230707A: Swift-XRT observations
- GRB 230707A: Fermi GBM Detection
- GRB 230707A: Swift ToO observations
- GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
- IBAS trigger number 10311: not a real GRB
- GRB 230328B: LBT detection of the likely host galaxy
- GRB 230628E: Swift/UVOT Detection
- GRB 230628E: Swift-BAT refined analysis
- GRB 230628E: ATCA rapid radio follow-up
- LIGO/Virgo/KAGRA S230627c: Upper limits from Swift/BAT-GUANO
- IPN triangulation of GRB 230625B (ultra-long)
- GRB 230625B: CALET Gamma-Ray Burst Monitor detection
- GRB 230625B: AstroSat CZTI detection
- GRB230628E: VLT optical identification of afterglow candidate
- GRB 230628E: Swift-XRT refined Analysis
- GRB 230628E: Enhanced Swift-XRT position (Correction to name in GCN 34115)
- GRB 230628A: Enhanced Swift-XRT position
- GRB 230628E: LCOGT Optical Upper Limit
- Swift GRB230628.93: Global MASTER-Net observations report
- GRB 230628E: Swift detection of a burst
- GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
- GRB 230623B: CALET Gamma-Ray Burst Monitor detection
- Konus-Wind detection of GRB 230616A
- GRB 230618A: Swift-BAT refined analysis
- GRB 230625B: Swift/BAT-GUANO detection of a long burst
- GRB 230622A: Swift-BAT refined analysis
- GRB 230623A: Swift-XRT observations
- GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
- GRB 230623A: Tiled Swift observations
- GRB 230623A: Tiled Swift observations
- GRB 230622A: ATCA rapid radio follow-up
- GRB 230622A: Swift-XRT refined Analysis
- Swift GRB 230622A: Global MASTER-Net observations report
- GRB 230622A: Swift detection of a burst
- Fermi GBM-230619: A soft subthreshold candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
- ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Swift/UVOT detection
- IPN triangulation of GRB 230616A (short)
- AT2023lcr: Neil Gehrels Swift Observatory X-ray detection
- GRB 230618A: Osservatorio Astronomico Nastro verde upper limit
- GRB 230618A: Enhanced Swift-XRT position
- GRB 230618A: Swift/UVOT Upper Limits
- GRB 230618A: Swift-XRT refined Analysis
- GRB 230616A: Swift-XRT observations
- GRB 230618A: KAIT Optical Observations
- Swift GRB 230618A: Global MASTER-Net observations report
- GRB230618A: LCOGT Optical Observations
- GRB 230618A: Prompt enhanced Swift-XRT position
- GRB 230618A: Swift detection of a burst
- GRB 230616A: Swift ToO observations
- GRB 230616A: AstroSat CZTI detection
- GRB 230616A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
- GRB 230614B: Fermi GBM Observation
- GRB 230614B: Swift/BAT-GUANO detection outside the coded FOV
- GRB 230606A: LCOGT Optical Observations
- GRB 230506B: Chandra localization of the X-ray afterglow
- GRB 230606A: Swift-BAT refined analysis
- GRB 230606A: Gaoyazi/GOT optical upper limit
- GRB 230606A: Fermi GBM Observation
- GRB 230606A: BOOTES-5/JGT optical upper limit
- GRB 230606A: Swift-XRT refined Analysis
- GRB 230606A: Swift/UVOT Upper Limits
- GRB 230606A: Enhanced Swift-XRT position
- GRB 230606A: Swift detection of a burst
- GRB 230510A: Swift-BAT refined analysis
- GRB 230523B: GRBAlpha detection
- GRB 230523B: Name correction from GCN Circular 33859
- GRB 230523A: Swift/BAT-GUANO detection of a short hard burst
- LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for MeerLICHT candidates: AT2023ixg and AT2023iyb
- IPN triangulation of GRB 230518A (short)
- LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for Swope candidates: SSS23a, SSS23b and SSS23c
- GRB 230518A: Fermi GBM Observation
- GRB 230518A: Swift/BAT-GUANO detection
- LIGO/Virgo S230518h: Swift XRT observations, 8 X-ray sources
- Improved IPN triangulation of GRB 230512A
- IPN triangulation of GRB 230512A
- GRB 230512A: Nanshan/NEXT non-detection of GRB afterglow candidate
- GRB 230512A: Liverpool Telescope observations
- GRB 230512A: Kitab possible afterglow candidate
- GRB 230510A: GRBAlpha detection
- GRB 230512A: Swift-XRT observations
- GRB 230512A: Tiled Swift observations
- GRB 230512A: Fermi-LAT detection
- GRB 230510A: GIT optical upper limits