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"42773 results found.
- GRB 070621: NOT observations
- GRB 070621: TAROT Calern observatory optical observations
- GRB 070621: ROTSE-III Prompt Optical Limits
- GRB 070621: Swift detection of a burst
- GMRT upper limit of GRB 070610/SWIFT J195509.6+261406 in 610 MHz
- GRB 070612A: TNG optical observations
- Swift/UVOT detection of GRB070616 optical afterglow.
- GRB070612A: Gemini Spectroscopic Redshift
- GRB 070612A: NOT observations
- GRB070616: Optical Observation by MITSuME Akeno
- GRB 070612B: Optical Observation by MITSuME Akeno
- GRB070616: Optical Observation by MITSuME Okayama
- GRB 070616, Swift-BAT further refined analysis
- GRB 070616: Swift XRT refined circular
- GRB 070612A: Possible WSRT Radio Detection
- GRB 070616: BTA astrometry and finding chart
- GRB 070616: BTA optical observations
- Swift/UVOT observations of GRB070616
- GRB 070616: TLS observation
- Swift XRT observations of the INTEGRAL burst GRB070615: Possible
- GRB 070616, Swift-BAT partial refined analysis
- GRB 070616: Swift detection of a burst
- GRB 070612B: optical observations
- UVOT Observations of INTEGRAL burst GRB070615
- VLA upper limit on GRB 070610
- GRB 070615
- GRB 070615: A long GRB detected by INTEGRAL
- SWIFT J195509.6+261406 (GRB 070610): further observations
- GRB 070612A: Super-LOTIS observations
- GRB 070612A: Rapid Decay
- GRB 070612A: Suzaku/WAM observation of the prompt emission
- SWIFT J195509.6+261406 / GRB 070610: OPTIMA-Burst observations
- GRB070612A: MITSuME Okayama Observation
- GRB 070612A: continued SARA observations
- GRB 070612A: spectral lag
- Swift Trigger 282176 is Cygnus X-1
- GRB 070612A: MDM Observations
- GRB 070612A: P60 Confirmation of Afterglow and An Underlying, Nearby
- GRB 070612B: SARA upper limit
- GRB 070612B, Swift-BAT refined analysis
- GRB 070612A, Swift-BAT refined analysis
- GRB 070612B: Swift-XRT refined analysis
- SWIFT J195509.6+261406 / GRB 070610: SWIFT continued observations
- GRB 070612B: Swift/UVOT upper limits
- GRB 070612B: FRAM limit
- GRB070612B: P60 Observations
- GRB 070612B: KAIT limits
- GRB 070612A: SARA detection of possible OT
- GRB 070610: TAROT Calern observatory optical observations
- GRB 070610: MITSuME OAO optical upper limit
- GRB 070612B: Swift detection of a burst
- GRB070612 - SDSS Pre-Burst Observations
- GRB 070612: Swift detection of a burst
- GRB 070610: OPTIMA-Burst detection of continued strong flaring activity
- GRB 070610: SARA upper limit
- GRB 070610: Swift-XRT refined analysis
- GRB 070610: TLS RRM sees flaring behaviour - Galactic transient?
- GRB 070611: Swift/UVOT Observations
- GRB 070611: Swift-XRT refined analysis
- GRB 070611, Swift-BAT refined analysis
- GRB 070610: Optical observations from OSN
- GRB 070611: VLT redshift
- GRB 060121 : pseudo-z = 1.9 ('intermediate-duration' burst)
- GRB 070611; Swift-XRT position
- GRB 070611: ROTSE-III Optical Limits
- GRB 070611: Swift detection of a burst
- GRB 070610: Swift-UVOT Upper Limits
- GRB 070610: OPTIMA-Burst high-time-resolution optical observations
- GRB 070610, Swift-BAT refined analysis
- GRB 070610; Swift-XRT position
- GRB 070610: Swift detection of a burst
- GRB 070412: TAROT Calern observatory optical observations
- GRB 070411: TAROT Calern observatory optical observations
- GRB 070419A, deep LBT photometry and possible supernova detection
- GRB070520B: optical observations
- GRB070520: optical observation
- GRB070518: optical observation
- GRB070521: optical observation
- Swift/UVOT refined analysis of GRB070531
- GRB 070531: NOT nIR observations
- GRB 070531: I-band observations from IAC80
- GRB 070531: Swift-XRT position
- GRB 070531: Liverpool Telescope Optical Observations
- GRB 070531: Swift detection of a burst
- GRB 070529: SARA upper limit
- Swift/UVOT refined analysis of GRB070529
- GRB 070529: MARGE Observations
- GRB 070529: Optical aterglow from MIRO
- GRB 070529: Gemini Redshift
- GRB 070529: Swift-XRT refined analysis
- GRB 070529, Swift-BAT refined analysis
- GRB 070529: Xinglong TNT Optical Upper Limit
- GRB 070529: Swift detection of a burst with an optical aterglow
- GRB 070412: Deep Keck imaging
- Swift Triggers 280447, 280450 and 280451 are invalid
- Swift trigger 280447 is probably a Galactic transient
- GRB 070518, deep LBT photometry
- GRB 070518: MARGE Observations
- Konus-Wind observation of GRB 070521
- GRB 070518: optical observation