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').
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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.
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subject:"Swift"body:"GRB"submitter:"Judith Racusin"- GRB 080701A: Early RAPTOR optical limits
- Swift Trigger 315630: Swift/UVOT Upper Limits
- GRB 080702A, Swift-BAT refined analysis
- GRB 080702A: Swift-XRT Team refined analysis
- GRB 080702B : Burst detected in BAT during Swift slew
- GRB 080702A: Enhanced Swift-XRT position
- Swift Trigger 315630: TLS R-band observation
- Swift Trigger 315630: Probably not a GRB
- GRB 080702: Swift detection of a short burst
- GRB 080701: Swift-XRT refined analysis
- GRB 080701A, VATT optical upper limit
- TLS I-Band Observation of GRB 080701A
- GRB 080701A: Swift/UVOT Upper Limits
- GRB 080701A: Early Super-LOTIS Observations
- GRB 080701: Enhanced Swift-XRT position
- GRB 080701A, Swift-BAT refined analysis
- Trigger 315630: Swift detection of a possible burst
- GRB 080701: Swift-XRT Prompt Analysis
- GRB 080701: Swift detection of a burst
- GRB 080623: Suzaku WAM observation of the prompt emission
- GRB 080625: Swift/UVOT Follow-Up Observations
- GRB 080625: Further observations from OSN
- GRB 080625:Swift-XRT detection of the afterglow
- GRB 080625: Swift/UVOT Detection of an Optical Afterglow
- GRB 080625: Observations at OSN
- GRB 080625: Gamma Ray Burst Localization by SuperAGILE
- GRB 080623: GROND upper limits
- GRB080623: Swift UVOT followup observations
- GRB 080623: Swift-XRT refined analysis
- GRB 080623, Swift-BAT refined analysis
- GRB 080623: Enhanced Swift-XRT position
- GRB 080623: TAROT La Silla observatory optical observations
- GRB 080623: Swift/UVOT Non-Detection of an Optical Afterglow
- GRB 080623: Swift XRT prompt analysis
- GRB 080623: Swift detection of a burst
- Swift trigger 314975 is not a GRB
- Swift-BAT trigger 314975 possible burst
- GRB080607: optical observation
- GRB 080603b: optical observation
- GRB 070809: Putative host galaxy and redshift
- VLA upper limit on INTEGRAL burst GRB 080613A
- GRB 0800603A: optical observation
- GRB080613B: MITSuME upper limits
- GRB080613A: Optical upper limits with Okayama MITSuME telescope
- Konus-Wind observation of GRB 080613B
- GRB 080603A: optical observations on June 04
- GRB 080613A: Swift-XRT detection of the afterglow
- GRB080613A: Swift/UVOT Upper Limits
- GRB 080613A: GROND Confirmation of the Afterglow Candidate
- GRB 080613B: GROND Upper Limits
- GRB 080613B - NOT optical and IR nondetections
- GRB080613B: Swift/UVOT Upper Limits
- GRB 080613B, Swift-BAT refined analysis
- GRB 080613B: Swift-XRT refined analysis
- GRB 080514B: Spectroscopic constraints and probable host galaxy
- GRB 080613B: Swift detection of a burst
- GRB 080613: Faulkes Telescope North optical candidate
- GRB 080613 : a long GRB detected with INTEGRAL
- GRB 080603A: Late-time Keck imaging and spectroscopy
- GRB 080603b: optical observation
- Swift observations of BAT Slew Survey event (Trigger=010)
- GRB 080603A: final Swift-XRT observations.
- GRB 080607: AGILE-MCAL observation of the prompt emission
- GRB 080603B - TLS 2nd Epoch: Another Break
- GRB 080605: TLS 3rd Epoch - Source Confusion
- GRB080605: optical observation with the MITSuME-OAO telescope
- Konus-Wind observation of GRB 080607
- GRB080607: RTT150 optical observations
- GRB 080603A: optical observations
- GRB 080607: Swift-XRT refined analysis
- Swift/UVOT Observations of GRB080607
- GRB 080605: optical observations
- GRB 080607 KAIT observations
- VLA detection of INTEGRAL burst GRB 080603A
- Konus-Wind observation of GRB 080605
- GRB 080607: Enhanced Swift-XRT position
- GRB 080607, Swift-BAT refined analysis
- GRB 080605: GROND 2nd epoch observations
- GRB 080607 - PAIRITEL NIR detection
- GRB 080607: Keck/LRIS spectroscopy and redshift
- GRB 080607: Super-LOTIS early observations
- GRB 080607: Swift detection of a burst with optical afterglow
- GRB 080607: ROTSE-III Detection of Optical Counterpart
- GRB 080605: TLS RRM Analysis, Plateau/Rebrightening, Red OT
- GRB 080605: Swift-UVOT refined analysis
- Possible VLA radio detection on INTEGRAL burst GRB 080603A
- GRB 080604: VLA radio upper limit
- GRB 080605, Swift-BAT refined analysis
- GRB 080603B: VLA radio upper limit
- GRB 080605, Swift-BAT refined analysis
- GRB 080605: Swift-XRT refined analysis
- GRB080605: observation by BOOTES
- GRB 080605: MASTER VWF 46 s AT observation
- GRB 080605: Enhanced Swift-XRT position
- GRB 080605: GROND detection of the optical afterglow candidate
- GRB080605: optical observations
- GRB 080605: VLT redshift
- GRB 080605: Liverpool Telescope optical afterglow candidate
- GRB 080605: Swift/UVOT Position of the Optical Afterglow
- GRB 080605: TLS RRM Afterglow