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"26290 results found.
- IBAS Alert n. 4144: not a GRB
- GRB 070224: Swift/UVOT Upper Limits
- GRB070224: Magellan Imaging Observations
- GRB070224: Gemini Imaging Observations
- GRB 070224: SARA upper limit
- GRB 070224, Swift-BAT refined analysis
- GRB 070224: MASTER-Net refind analysis
- GRB 070224: MASTER-VWF-Kislovodsk observations
- GRB 070224: Swift detection of a burst
- GRB070223: Swift/UVOT refined analysis
- GRB 070223, Swift-BAT refined analysis
- GRB070223: MASTER-VWF-Kislovodsk observations
- GRB 070223: Swift-XRT Refined Analysis
- GRB070223 - SDSS Pre-Burst Observations
- GRB 070223: Liverpool Telescope Possible Afterglow Candidate
- GRB070223: Swift burst
- Konus-Wind and Konus-A observations of GRB 070220
- GRB 070220 Swift-BAT Refined Analysis
- Swift/UVOT refined analysis of GRB070220
- GRB 070209: Swift XRT refined analysis
- GRB 070220: Swift-XRT Refined Analysis
- GRB 070220 : Faulkes Telescope North optical limit
- GRB 070220: Swift detection of a burst
- GRB070219: MASTER-VWF-Kislovodsk observations
- GRB 070219: XRT Refined Analysis
- GRB 070219: Swift/UVOT Upper limits
- GRB 070219, Swift-BAT refined analysis
- GRB 070219: Liverpool Telescope Observations
- GRB 070219: ROTSE-III Optical Limits
- GRB070219 - SDSS Pre-Burst Observations
- GRB 070219: Swift detection of a burst
- Swift-BAT trigger 260304 is NOT a burst or transient
- GRB 070209: Swift XRT analysis
- IPN localization of very bright long hard GRB 070207
- GRB 070209, Swift-BAT refined analysis of the short hard burst
- GRB 070209: Swift detection of a short hard burst
- GRB 070208: RAPTOR detection of early afterglow onset
- GRB 070208, Swift-BAT refined analysis
- GRB070208 - SDSS Pre-Burst Observations
- GRB 070208: Early IR detection and afterglow astrometry
- GRB070208: Faulkes Telescope North Afterglow Identification
- GRB 070208: ROTSE-III Optical Limits
- GRB 070208: Swift detection of a burst
- Swift-BAT trigger 259527 is a Cosmic Ray Shower
- GRB070126: Swift-XRT Observation
- GRB 070129: Swift/UVOT Upper limits
- GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
- GRB 070125: optical observation
- GRB070129: MITSuME optical observation
- GRB 070129, Swift-BAT refined analysis of a particularly long
- GRB 070129: Swift-XRT Refined Analysis
- GRB 070129: Swift detection of a burst
- GRB 070126: Swift/UVOT refined analysis
- GRB 070124: Suzaku WAM observation of the prompt emissions
- GRB 070125: UVOT Detection in Ultraviolet Filters
- GRB 070126, Swift-BAT refined analysis of a very faint burst
- GRB070124: Swift-XRT Observation
- Possible GRB 070126: Swift/UVOT Upper Limit
- GRB 070125: UVOT Observations of a Fading Optical Afterglow
- GRB 070125: Continued P60 Observations
- GRB070125: Swift-XRT Refined Analysis
- GRB 070126?: Swift detection of a possible burst
- IPN-BAT localization of GRB070125 (very long duration, intense)
- Konus-Wind observation of short hard GRB 070124
- Swift-BAT trigger 257213 is a Galactic Center transient
- GRB 070110: Continued Detection and Request for Ground Followup
- GRB 070107: Suzaku WAM observation of the prompt emission
- Further Retractions of previous Swift-BAT triggers
- Swift-BAT Trigger 255685 is not a GRB
- Trigger 255685: Swift detection of a possible burst
- GRB 070110: UVOT Observations of a Candidate Afterglow
- GRB070110: Swift XRT Team refined analysis
- GRB 070110, Swift-BAT refined analysis
- GRB 070110: Swift detection of a burst with a possible optical afterglow
- IBAS Alert n. 4047: Not a GRB
- GRB070107: Swift/XRT refined analysis
- GRB 070107: Possible UVOT Afterglow
- GRB 070107, Swift-BAT refined analysis
- GRB 070107: Swift detection of a burst
- GRB070103: APO SPIcam i' and z' limits
- GRB 070103: Swift/UVOT Upper limits
- GRB070103: Swift XRT refined analysis
- GRB 070103, Swift-BAT refined analysis
- GRB 070103: TAROT Calern observatory optical observations
- GRB 070103: Swift detection of a burst
- Retractions of previous Swift-BAT triggers
- Konus-Wind observation of GRB 061222A
- GRB 061222B: TAROT La Silla observatory early optical observations
- GRB 061218: TAROT La Silla observatory early optical observations
- GRB 061222A: MITSuME Akeno optical upper limits
- GRB 061222B: MITSuME Akeno optical upper limits
- GRB 061222B, Swift-BAT refined analysis
- GRB061222A Swift/UVOT: Upper Limits
- GRB 061222B: Swift/UVOT Upper limits
- GRB061222B: Swift-XRT Refined Analysis
- GRB 061222B: BOOTES-IR optical observations
- GRB 061222B: SARA upper limit
- GRB 061222A, Swift-BAT refined analysis
- GRB 061222B: TAROT La Silla observatory afterglow observation
- GRB 061222B: TAROT La Silla observatory optical observations