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"19938 results found.
- VLA observations of SGR 1806-20
- SGR1806 VLA Observations
- VLA observations of SGR 1806-20
- SGR1806-20: RXTE-PCA observation of the 041227 super-flare
- GRB 041217: Optical observations
- SGR1806-20: Swift-BAT observation of the 041227 super-flare
- Detection of the SGR 1806-20 giant outburst back-scattered by the
- The giant outburst from SGR 1806-20
- Giant flare from SGR 1806-20 detected by INTEGRAL
- GRB041228: ROTSE-III Optical Observations
- GRB041228: Swift-BAT detection of a burst
- GRB041219; RXTE ASM Observations
- NIR Observations of GRB 041219
- GRB041226: ROTSE-III Optical Observations
- GRB041226: Swift-BAT detection of a burst
- GRB041223: decay of the afterglow
- GRB041224: ROTSE-III Optical Observations
- GRB 041223: XRT afterglow spectrum and light curve
- GRB 041223 Fluence measured by Swift-BAT
- GRB041224: Swift-BAT detection of a soft burst
- GRB041223: optical and NIR observations with REM
- Swift-BAT Time History of GRB041219
- GRB041223: Swift XRT Detection of X-ray Afterglow Emission
- GRB041223: ROTSE-III Optical Observations
- GRB041223: Swift-BAT detection of a bright long burst
- Very high activity of SGR 1806-20
- GRB041220: Swift-BAT burst
- GRB 041219 Optical Observations
- GRB041219c: Third Burst in One Day from Swift-BAT
- GRB041219b: A Swift-BAT burst
- Swift-BAT detection of the bright long burst GRB041219
- GRB041217: optical limit 30 min after GRB
- GRB041217: Optical Observations
- GRB041217: NIR and optical observations with REM
- GRB041217: P60 Optical Observations
- GRB041217: Infrared Observations
- GRB041217: The First GRB Located On-Board Swift
- Summary of the recent bursts from SGR 1806-20
- IBAS GRB Alert # 2034
- Bright bursts from SGR1806-20
- Konus-Wind observation of a series SGR 1806-20 bursts on 041005
- Bursts from SGR 1806-20: Preliminary INTEGRAL results
- Very strong outburst from SGR 1806-20 detected with INTEGRAL
- SGR 1806-20 still active
- GRB040916: Optical observations
- An intense burst from SGR1806-20
- Very bright burst detected from SGR 1806-20
- Increase of SGR 1806-20 activity
- Bursting activity from SGR 1806-20 detected with IBAS
- Ongoing activity of SGR 1806-20
- GRB040706:observation at University of Miyazaki
- SGR 1806-20: no IR variability of the proposed counterparts
- SGR 1806-20, potential NIR counterpart
- Activivty of SGR 1806-20
- IBAS GRB Alerts n.1785 to 1791
- GRB040422: optical and NIR observations at the VLT
- Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
- IBAS GRB Alert 1694
- IBAS GRB alerts 1679, 1680, 1681
- GRB040223, improved XMM position
- IBAS results on a burst from SGR1806-20
- SN 2003jd (SN/GRB?) - possible association with GRB 030929
- IBAS alert 1180 refers to a burst from SGR 1806-20
- Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
- SGR1806-20 bursts on 031008. Helicon detection and small error box.
- SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
- A burst from SGR 1806-20 detected with IBAS
- IPN triangulation of GRB030926 (short/hard; large error box)
- IBAS detection of bursts from SGR 1806-20
- Radio Observations of SGR1806-20
- INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
- Summary of recent IPN and HETE detections of SGR bursts
- Clarification of GCN 2354 on SGR1806-20
- IPN detection of continued activity from SGR1806-20
- 030813 SGR event (Konus-Wind observation)
- SGR 1808-20 (=H2802): A Possible new SGR
- SGR 1806-20, submm observations
- RXTE PCA Observations of SGR1806-20 Region
- HETE detection of burst from SGR1806-20
- GRB030329 observed as a sudden ionospheric disturbance (SID)
- IPN triangulation of GRB021219
- IPN detection of continued activity from SGR1806-20
- IPN detection of renewed activity from SGR1806-20
- IPN detection of continued SGR1900+14 activity
- IPN confirmation of the reactivation of SGR1900+14
- IPN detection of possible reactivation of SGR1900+14
- IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
- SGR1900+14 activity, November 2-4, 2002
- Detection of activity from SGR 1900+14 with the RXTE/PCA
- IPN detection of a burst from SGR1900+14
- Gemini IR Detection of AXP 1E 2259+586 Post-Burst
- SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
- AXP 1E2259+586: quasi-simultaneous optical observation
- AXP 1E2259+586 optical observations
- SGR-like Bursts from the AXP 1E 2259+586
- IPN detection of possible bursts from SGR1806-20
- XRF 020427: Sudden Ionospheric Disturbance (SID)
- Mars Odyssey joins the IPN
- IPN detection and localization of Cygnus X-1 flares
- RXTE Observations of SGR 1900+14