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').
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"23584 results found.
- GRB 070224: SARA upper limit
- GRB 070224, Swift-BAT refined analysis
- GRB 070224: Swift detection of a burst
- RHESSI Spectrum of GRB070220
- GRB 070223: Optical-IR observation with KANATA
- GRB 070223, Swift-BAT 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: MITSuME Okayama Optical Observation
- GRB 070220: ART-3 Optical and NIR limits
- 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: Observation with the KANATA 1.5m telescope
- GRB 070220 : Faulkes Telescope North optical limit
- GRB 070220: Swift detection of a burst
- GRB 070219: XRT Refined Analysis
- GRB 070219: I-band observations
- GRB 070219, Swift-BAT refined analysis
- GRB 070219: optical TNG observations
- 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 060927: PROMPT Observations
- GRB 070125: Break in Optical Decay
- 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, Swift-BAT refined analysis
- GRB070208 - SDSS Pre-Burst Observations
- GRB070208: Faulkes Telescope North Afterglow Identification
- GRB 070208: Swift detection of a burst
- GRB 070125 detection with CARMA
- GRB 070129: Swift/UVOT Upper limits
- GRB061217: MAGIC telescope GeV observation
- GRB 070129, Swift-BAT refined analysis of a particularly long
- GRB 070129: VLT observations
- GRB 070129: Swift detection of a burst
- GRB 070125: MITSuME Okayama optical observation
- GRB 070125: AAVSO optical observations
- GRB 070125: PROMPT detections
- 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
- GRB070125: Optical observation by Kanata
- GRB070124: Swift-XRT Observation
- GRB 070126?: Swift detection of a possible burst
- RHESSI Spectrum of GRB070125
- IPN-BAT localization of GRB070125 (very long duration, intense)
- Konus-Wind observation of short hard GRB 070124
- IPN localization of GRB070124 (short duration, hard spectrum)
- GRB 070110: Continued Detection and Request for Ground Followup
- GRB 050904: Second Epoch of HST/NICMOS Observations
- GRB 070110: Ep,i - Eiso correlation
- GRB 070107: Suzaku WAM observation of the prompt emission
- GRB 070110 declared a "Burst of Interest" by Swift team
- Swift-BAT Trigger 255685 is not a GRB
- Trigger 255685: Swift detection of a possible burst
- GRB070110: Swift XRT Team refined analysis
- GRB 070110, Swift-BAT refined analysis
- GRB 070110: Swift detection of a burst with a possible optical afterglow
- GRB 070107: Possible UVOT Afterglow
- GRB 070107, Swift-BAT refined analysis
- GRB 070107: Swift/XRT position
- GRB 070107: Swift detection of a burst
- GRB070103: APO SPIcam i' and z' limits
- GRB 061201: Nearby Galaxy Cluster Abell 995 is at z=0.0865
- GRB070103: KPNO 4m+FLAMINGOS J limit
- GRB 070103, Swift-BAT refined analysis
- GRB 070103: TAROT Calern observatory optical observations
- GRB 070103: Swift detection of a burst
- Konus-Wind observation of GRB 061222A
- GRB 061210: Swift/XRT Astrometry Correction
- GRB 061222B: TAROT La Silla observatory early optical observations
- GRB 061218: TAROT La Silla observatory early optical observations
- GRB 061222B, Swift-BAT refined analysis
- GRB 061222B: Observation with the KANATA 1.5m telescope
- GRB 061222A: Observation with the KANATA 1.5m telescope
- GRB 061222B: BOOTES-IR optical observations
- GRB 061222A, Swift-BAT refined analysis
- GRB 061222B: TAROT La Silla observatory afterglow observation
- GRB 061222B: TAROT La Silla observatory optical observations
- GRB 061222B: Swift detection of a burst
- GRB 061222: Swift detection of a burst
- GRB 061217: Astrometry-Corrected XRT Position
- GRB 061217: Confirmation of host candidate
- GRB 061217: Extended object in the revised XRT error circle
- GRB 061217, Candidate host galaxy
- GRB 061210: Possible Host Galaxy (S2-G2) Keck Spectrum
- GRB 061201: Magellan Redshift of nearby Abell cluster
- GRB 061218: TAROT La Silla observatory optical observations