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"35321 results found.
- GRB240730A: BOOTES-5/JGT early optical upper limit
- Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
- Fermi GRB 240730B: Global MASTER-Net observations report
- GRB 240730B: Fermi GBM Final Real-time Localization
- Swift GRB 240730A: Global MASTER-Net observations report
- GRB 240730A: Swift-XRT refined Analysis
- GRB 240715A: Swift-XRT afterglow detection
- GRB 240730A: KAIT Optical Upper Limit
- GRB 240727C: GRBAlpha detection
- GRB 240730A: Swift/UVOT Upper Limits
- GRB 240730A: Enhanced Swift-XRT position
- GRB 240730A: Swift detection of a burst
- GRB 240727A: Swift-BAT refined analysis
- Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
- GRB 240727A: observations of optical counterpart.
- GRB 240727B: Swift-XRT observations
- Fermi GRB 240727A: Global MASTER-Net observations report
- GRB 240727A: Swift/UVOT detection
- Fermi Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
- GRB 240727A: Correction to time in GCN36960
- GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
- GRB 240727A: NOT optical observation
- GRB 240727A: JinShan optical upper limits
- GRB 240727A Bassano Bresciano Observatory upper limit
- GRB 240727D: Correction to the GRB name in GCN 36958
- GRB 240727A: Fermi GBM Final Real-time Localization
- GRB 240727C: AstroSat CZTI detection of a long burst
- GRB 240727A: Swift-XRT refined Analysis
- GRB 240720B: GRBAlpha detection
- GRB 240718A: GRBAlpha detection
- GRB 240710B: GRBAlpha detection
- GRB 240627A: GRBAlpha detection
- Fermi GRB 240726A: Global MASTER-Net observations report
- GRB 240727A: Enhanced Swift-XRT position
- GRB 240727B: Fermi GBM Observation
- GRB 240727B: Swift ToO observations
- GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
- GRB 240726A: SVOM/GRM observation
- GRB 240727B: AstroSat CZTI detection
- GRB 240726B: AstroSat CZTI detection of a short burst
- GRB240727A: Skynet Optical Afterglow Observations
- GRB 240727A: TRT optical afterglow detection
- GRB 240727A: KAIT Optical Afterglow Candidate
- GRB 240727A: Swift detection of a burst
- GRB 240726A: AstroSat CZTI detection of a short burst
- IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
- GRB 240726A: Fermi GBM Final Real-time Localization
- Swift Trigger 1244778 is not a GRB
- GRB 240720A: Swift-BAT refined analysis
- IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
- LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
- LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
- Fermi Gamma-ray Burst Monitor trigger 743271526/240721680 is not a GRB
- Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
- GRB 240720B: SVOM/GRM observation
- GRB 240721A: Fermi GBM Final Real-time Localization
- GRB 240720B: AstroSat CZTI detection of a short burst
- Fermi GRB 240720A: Global MASTER-Net observations report
- GRB 240720A: AstroSat CZTI detection
- GRB 240720A: Fermi GBM observation
- GRB 240720A: Swift detection of a burst
- Konus-Wind detection of GRB 240718A
- GRB 240713A: SVOM/GRM observation
- Fermi GRB 240718A: Global MASTER-Net observations report
- GRB 240718A: Fermi GBM Observation
- GRB 240718A: Fermi-LAT Detection
- GRB 240718A: SVOM/GRM observation
- GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
- GRB 240718A: Fermi GBM Final Real-time Localization
- GRB 240712A: Swift-BAT refined analysis
- GRB 240716A: GECAM-B detection of a long burst
- SVOM/GRM In-Flight Trigger of GRB 240716A
- GRB 240713A: 2.2m CAHA optical limit
- GRB 240715A: Swift/UVOT observations of the XRT sources.
- GRB 240715A: Swift-XRT observations
- GRB240713A: Swift/UVOT Upper LImits
- GRB 240715A: GECAM-C detection of a short burst
- Konus-Wind detection of GRB 240715A
- GRB 240713A: Swift-XRT observations
- GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
- GRB 240712A: Swift-XRT refined Analysis
- SVOM/GRM In-Flight Trigger of GRB 240715A
- GRB 240713A: LAST optical upper limit
- GRB 240715A: Swift ToO observations
- Fermi GRB 240715A: Global MASTER-Net observations report
- GRB 240713A: optical upper limits from the INAF Asiago Observatory
- GRB 240715A: Fermi GBM Observation
- GRB 240712A ATCA radio observations
- GRB240715A: GRANDMA Optical Upper Limits
- IPN triangulation of GRB 240715A (short)
- GRB 240712A: Swift/UVOT Upper Limits
- GRB 240715A: Fermi GBM Final Real-time Localization
- GRB 240713A: Tiled Swift observations
- GRB 240713A: J-band upper limit from WINTER
- GRB 240713A: NOT optical upper limits on three EP/FXT candidates
- GRB 240713A: JinShan optical upper limits
- GRB 240713A: OHP/T120 optical upper limit
- GRB240713A: X-ray follow-up observation with EP-FXT
- GRB 240713B: AstroSat CZTI detection of a long burst
- Fermi Sub-threshold Observation of GRB240713A