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"19350 results found.
- GRB 070125: X-ray light curve analysis
- VLA observation of GRB 070306
- GRB 070306: NOT observations
- GRB 070306 Swift/UVOT refined analysis
- GRB 070306, Swift-BAT refined analysis
- GRB 070306: XRT Team Refined Analysis
- GRB070306 - SDSS Pre-burst Observations
- GRB 070306: Swift detection of a burst
- GRB070227: Swift-XRT refined analysis
- GRB 070125, deep late-time optical observation
- VLA observation of GRB 070224
- GRB 070227: optical observations
- GRB 070223: Optical Observations
- GRB 070227: optical observations
- GRB 070227: Swift/UVOT Upper Limits
- GRB 070227: TAROT La Silla observatory optical observations
- GRB 070227, Swift-BAT refined analysis
- GRB070227: possible X-ray afterglow detection
- GRB 070227: Swift detection of a burst in ground analysis
- GRB 070224: Optical afterglow confirmation
- GRB 070224: Swift/UVOT Upper Limits
- GRB070224: Swift-XRT Astrometrically Corrected Position
- VLA observation of GRB 070223
- VLA observation of GRB 070220
- GRB070224: Magellan Imaging Observations
- GRB070224: Gemini Imaging Observations
- GRB 070224: SARA upper limit
- GRB070224: Swift-XRT Refined Analysis
- 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
- GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
- GRB 070223: MDM Observations
- 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: 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: 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
- GRB 070208: MARGE Optical Observations
- IPN localization of very bright long hard GRB 070207
- IPN localization of very intense short GRB 070201
- GRB 070209, Swift-BAT refined analysis of the short hard burst
- GRB 070209: Swift detection of a short hard burst
- GRB 070208: Swift XRT refined analysis
- GRB 070208: RAPTOR detection of early afterglow onset
- GRB 070208: MDM Optical Decay
- GRB 070208, Swift-BAT refined analysis
- GRB070208: Faulkes Telescope North Afterglow Identification
- GRB 070208: ROTSE-III Optical Limits
- GRB 070208: MDM Observations
- GRB 070208: Swift detection of a burst
- Swift-BAT trigger 259527 is a Cosmic Ray Shower
- GRB070124: Swift-XRT Follow-up Observation
- GRB070126: Swift-XRT Observation
- GRB 070129: Swift/UVOT Upper limits
- GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
- GRB061217: MAGIC telescope GeV observation
- GRB 070129, Swift-BAT refined analysis of a particularly long
- GRB 070129: Swift-XRT Refined Analysis
- GRB 070125: An IR Point Source and an Apparent Host Galaxy
- GRB 070129: Swift detection of a burst
- GRB 070126: Swift/UVOT refined analysis
- GRB070126: Swift-XRT possible detection of an afterglow
- 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: pseudo-z~1.5 from spectral parameters of the prompt emission
- GRB070125: Swift-XRT Refined Analysis
- GRB 070126?: Swift detection of a possible burst
- IPN-BAT localization of GRB070125 (very long duration, intense)
- IPN localization of GRB070124 (short duration, hard spectrum)
- Swift-BAT trigger 257213 is a Galactic Center transient
- GRB 070110: Continued Detection and Request for Ground Followup
- GRB 070110: Ep,i - Eiso correlation
- GRB 070110 declared a "Burst of Interest" by Swift team
- 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
- GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow