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"22914 results found.
- XRF030723, BVRcIc field photometry
- XRF 030723, optical observations
- XRF 030723, optical observations
- XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
- SGR 1806-20, submm observations
- IPN triangulation of GRB030717 (annulus)
- RXTE PCA Observations of SGR1806-20 Region
- IPN triangulation of GRB030714 (two large error boxes)
- IPN triangulation of GRB030715 (two large error boxes)
- IPN detection of renewed activity from SGR1806-20
- IPN triangulation of GRB030711 (annulus, =SGR0525-66?)
- IPN triangulation of GRB030710 (annulus)
- IPN triangulation of GRB030709 (annulus)
- GRB030706 triangulation (single large error box)
- IPN triangulation of GRB030706 (annulus)
- IPN triangulation of GRB030629 (annulus)
- GRB030629 triangulation (Konus-Wind -- Helicon annulus)
- GRB030329, optical observation in May
- IPN triangulation of GRB030626 (single large error box)
- IPN triangulation of GRB030626 (two large error boxes)
- GRB030329: second XMM-Newton observation
- GRB030329 -- RATAN-600 data in April-May
- Final IPN error ellipse for GRB021206 (the polarized GRB)
- GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
- IPN triangulation of GRB030607 (annulus)
- IPN triangulation of GRB030606 (two alternate error boxes)
- GRB030329, SPM optical observations (Correction of GCN2075 R band)
- GRB 030528: Infrared Observations and the Proposed IR Counterpart
- IPN triangulation of GRB030605B (annulus)
- IPN triangulation of GRB030605 (annulus)
- GRB 030528: tentative NIR counterpart
- GRB 030528, radio observations
- GRB030528(=H2724): Observations with the Chandra X-ray Observatory
- GRB030528, BVRI field photometry
- IPN triangulation of GRB030601 (annulus)
- GRB030329, SPM optical observations
- GRB030528: Chandra TOO Planned
- GRB 030519B: optical observations.
- MASTER: optical observation GRB030601
- GRB030528(=H2724): Revised SXC Localization
- GRB 030528 Bisei optical observation
- GRB 030528 (=H2724) Kyoto optical observation
- IPN triangulation of GRB030523B (annulus)
- GRB 030416: Optical Observations
- IPN triangulation of GRB030523 (annulus)
- GRB 030329 Optical Observations
- GRB 021004: HST observations
- GRB030324: Further Observations of the Candidate Optical Afterglow
- GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
- IPN triangulation of GRB030519B=H2716 (small error box)
- GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
- IPN triangulation of GRB030519 (annulus)
- IPN triangulation of GRB030518C (annulus)
- IPN triangulation of GRB030518B (annulus)
- IPN triangulation of GRB030518A (annulus)
- IPN triangulation of GRB030514 (annulus)
- HETE GRB030329, correction to Rc Observations in Loiano
- IPN triangulation of GRB030513 (annulus)
- IPN triangulation of GRB030509B (annulus)
- GRB 030329: Optical limit (contemporaneous imaging)
- IPN triangulation of GRB030509 (small errror box)
- IPN triangulation of GRB030509 - correction
- IPN triangulation of GRB030509 (single error box)
- GRB030329, BVRI photometry
- GRB030429, refiend optical brightness
- GRB 030329: Optical limit (contemporaneous photography)
- GRB030418, BVRcIc field photometry
- GRB030429, BVRcIc field photometry
- IPN triangulation of GRB030506 (annulus)
- IPN triangulation of GRB030505B (large error box)
- IPN triangulation of GRB030505A (annulus)
- GRB030329: RTT150 optical observations and upper limit for a host
- GRB030501, optical observation
- GRB030501C triangulation (annulus)
- GRB030501 triangulation (correction to GCN 2194)
- GRB030329: RTT150 optical observations and upper limit for a host
- GRB 030429: Radio Observations
- GRB 030429: redshift from VLT spectroscopy
- GRB030501B triangulation (single error box)
- GRB030501: TAROT candidate afterglow present in archival images
- GRB 030501: TAROT possible candidate counterpart
- IPN triangulation of GRB030501 (IBIS event; annulus)
- IPN triangulation of GRB030501B (annulus)
- GRB 030429: confirmation of afterglow candidate
- GRB030501 localized by INTEGRAL
- GRB030425: CrAO optical observation
- IPN triangulation of GRB030429 (annulus)
- IPN triangulation of GRB030428 (two large error boxes)
- GRB 030329 Oprical observations in Rozhen observatory
- GRB 030324: Radio Observations
- IPN triangulation of GRB030426 (annulus)
- IPN triangulation of GRB030425 (single error box)
- GRB 030329, the review of the sky area in plate archive (1950-1998)
- IPN triangulation of GRB030422C (annulus)
- IPN triangulation of GRB030422B (annulus)
- GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
- GRB030329: optical polarization
- IPN triangulation of GRB030422 (two large error boxes)
- IPN triangulation of GRB030421 (annulus)
- MASTER:optical observations GRB030418