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"
4930 results found.
- GRB030329 Radio 23/43/90 GHz observations at Nobeyama
- GRB 030329: SARA Optical Observations
- GRB 030329, BRI photometry
- Further AAVSO V,B,R observations of GRB030329
- GRB 030329: SARA Optical Observations
- GRB 030329: Observations with ANDICAM
- GRB030329: further optical photometry and evidence for a light curve discontinuity
- GRB 030329: Correction to GCN 2056
- AAVSO V & R observations of GRB030329
- GRB 030329: optical observations
- GRB030329 15 GHz radio observation
- 030331 NOT A GRB
- GRB030329: R and B observations
- GRB030329, SPM optical observations
- GRB 030329: Optical Decay
- GRB030329: optical spectroscopy with the TNG
- GRB 030328 Optical Observations
- GRB030328: Decay index
- GRB030323 optical observations
- GRB030323: Detection on 2003/03/24
- GRB 030323: SARA Optical Observations
- GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
- GRB 030227: Optical limit at RIKEN
- GRB 030226 Optical observations
- Chandra detection of the X-ray afterglow of GRB 030226
- GRB030227: Kiso optical upper limit
- 030302: NOT A GRB
- Possible break in the GRB 030226 light curve
- GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
- GRB 030226 simultaneous optical observations
- GRB030226: Optical decay index
- GRB030131: Candidate Optical Afterglow
- GRB 030131: afterglow candidate
- GRB 030115, simultaneous observations by BOOTES-1
- GRB 030115: Radio Observations
- GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
- GRB 030115, optical candidate
- Possible GRB030113 seen by SPI ACS
- Probable GRB030112B seen by SPI ACS
- Probable GRB030112 seen by SPI ACS
- Possible GRB030111 seen by SPI ACS
- Possible GRB030110b seen by SPI ACS
- Possible GRB 030110 seen by SPI ACS
- GRB021112 (=H2448): A Long GRB Localized by HETE
- GRB021104: possible optical afterglow
- GRB021016, optical observations
- GRB021004: Optical Observations
- GRB021004: BVRc photometry
- GRB021004 radio observation
- GRB 021004: Optical Decay
- GRB 021004: Optical Observations
- GRB 021004: Optical Observations
- GRB 021004, optical observations
- GRB 021004 radio search
- INTEGRAL GRBs added to GCN
- GRB 020812: early time optical observation at Ouda Station
- Early Time Limits for GRB020813
- GRB 020813 Afterglow Observations; Possible break
- GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
- GRB020801: Imaging of Suggested OT Counterpart at the Magellan
- IPN triangulation of GRB020714
- IPN triangulation of GRB020714
- GRB 020625, optical observations
- AXP 1E2259+586 optical observations
- IPN detection of possible bursts from SGR1806-20
- GRB 020409: No Evidence for an Optical Afterglow
- GRB020331 optical observations with RIMOTS
- Short RXTE/ASM transient 020406; may be a GRB
- Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
- GRB011212: Optical Observations
- Bepposax GRB020322 The second springtime BSAX GRB
- GRB 020317 : KISO Optical Observations
- GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
- GRB020127 Optical Observations
- GRB011212: Optical observations at Gunma
- GRB 011211, Optical Observations
- GRB 011130: Optical Observations of Chandra Sources
- GRB 011130 I-band Observation
- GRB011130 (XRF011130) SDSS PT i-band observations
- XRF011130: Infrared Observations
- GRB011130, Radio Observations
- GRB010921, optical observation
- GRB010921 Optical Observations
- SGR1900+14 burst seen by HETE: BeppoSAX data
- GRB 010629 Optical Observations
- SGR1900+14: High Fluence Burst Localized by HETE
- GRB010326: Localization by HETE
- Sub-millimeter Excess/GRB 010222
- GRB010222: Sub-millimeter detection
- GRB010214 Optical Observation
- CORRECTION to XMM-Newton observation of GRB001025
- XMM-Newton observation of GRB001025
- CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
- ASM Localization of GRB 001025
- GRB 001007, BVR-band observations
- GRB000926 - Amateur Optical Observations
- GRB000926 optical observations
- GRB 000615, near-infrared observations
- IPN triangulation of GRB000516
- GRB 000418, Optical Observation