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"11836 results found.
- GRB 081009: Fermi GBM detection
- GRB 081012: GROND upper limits
- GRB 081012, Swift-BAT refined analysis
- GRB 081012: ROTSE-III Optical Limits
- GRB 081012: Swift detection of a burst
- Konus-Wind observation of GRB 081001
- GRB 081008: Gemini-South Absorption Redshiftt
- GRB 081008: VLT/FORS2 spectroscopy
- GRB081006B: Fermi GBM detection
- GRB 081007: Swift detection of a burst with optical afterglow
- Fermi GBM detection of additional bursts from AXP 1E1547.0-5408
- GRB081003B: Optical limits from Spain
- GRB 081003A: Swift-XRT Team position and analysis
- GRB 081003B: a long GRB detected with INTEGRAL
- GRB 080928: Fermi GBM detection
- AXP 1E1547.0-5408 (SGR 1550-5418): Fermi GBM detection
- GRB 081003: A long GRB discovered by INTEGRAL
- SGR 1550-5418 = AXP 1E1547.0-5408 (Trigger 330353)
- Swift discovery of a new Soft Gamma Repeater SGR 1550-5418
- Trigger 330353: Swift detection of a Galactic short soft burst
- GRB081001: SuperAGILE Localization of a long GRB
- GRB 080928: VLT redshift
- GRB 080928: Swift/UVOT observations
- GRB 080928A: ROTSE-III Confirmation of Optical Counterpart
- GRB 080928: Swift detection of a burst with an optical counterpart
- GRB 080920: Fermi GBM detection
- GRB080922, optical upper limit
- Swift detection of a possible GRB (trigger 325707)
- GRB080916A: Suzaku WAM observation of the prompt emission
- GRB 080922: Swift/UVOT Upper Limits
- GRB080922: A long GRB detected by INTEGRAL
- SGR 0501+4516: preliminary results of the Suzaku ToO observation
- Konus-Wind observation of GRB 080916A
- Konus-Wind observation of GRB 080916C
- GRB 080913: Konus-Wind and Swift/BAT joint spectral analysis
- GRB 080916B: Swift-XRT afterglow detection
- GRB 080916: REM candidate afterglow
- GRB 080916: Swift detection of a burst with optical afterglow
- GRB 080915: Swift-XRT afterglow detection and analysis
- SGR 0501+4516 : P200 i-band observations
- GRB 080915: ROTSE-III Optical Limits
- GRB 080915: Swift detection of a burst
- GRB 080913: Swift-XRT refined analysis
- GRB 080913: Swift detection of a burst
- SGR J0501+4516: radio pulsar searches with GBT and WSRT
- GRB 080905B: Watcher optical detection
- GRB 080905B: Fermi Gamma-ray Burst Monitor detection
- GRB 080906: Swift-XRT Refined Analysis
- GRB 080906: GROND observations of the optical/NIR afterglow
- GRB 080905B: Refined UVOT Analysis
- GRB 080905B: VLT redshift
- GRB 080905B: Swift detection of a burst with possible optical counterpart
- GRB 080905: Swift detection of a probably-short burst
- GRB 080903: ROTSE-III Optical Limits
- Recent VLA non-detection of SGR 0501+4516
- GRB 080830: Fermi Gamma-ray Burst Monitor detection
- SGR 0501+4516: Spin Down Rate and Inferred Dipole Magnetic Field
- SGR 0501+4516: preliminary results of the first XMM-Newton observation
- nIR observations of SGR 0501+4516
- INTEGRAL ToO observation of SGR0501+4516
- SGR 0501+4516: Confirmation of the NIR counterpart
- SGR 0501+4516: Detection of possible optical counterpart
- SGR 0501+4516: WHT observations of the possible near-infrared counterpart
- VLA non-detection of SGR 0501+4516
- Radio Detection of SGR 0501+4516: Retraction
- SGR 0501+4516: XMM-Newton monitoring schedule
- GRB 080828: SuperAGILE GRB Localization
- SGR 0501+4516: Decline in Activity
- SGR 0501+4516: Proximity to supernova remnant HB9
- Enhanced Swift-XRT position of SGR 0501+4516
- SGR 0501+4516: GMRT Radio Observation at 618 MHz
- SGR 0501+4516: Swift XRT measure of the spin period
- GRB080823: Fermi Gamma-ray Burst Monitor detection
- Konus-Wind observation of GRB 080825B
- SGR 0501+4516: Fermi GBM (formerly GLAST Burst Monitor) observations of three exceptionally intense outbursts
- Soft Gamma Repeater SGR 0501+4516: GBM Detection of multiple bursts
- Suzaku ToO Observation of SGR 0501+4516
- SGR 0501+4516: radio pulsar searches with GBT and WSRT
- GRB 080825B: GRB Localization by SuperAGILE
- Konus-Wind observations of new SGR 0501+4516
- INTEGRAL ToO Observation of SGR0501+4516
- Radio Detection of SGR 0501+4516
- SGR 0501+4516: MDM Optical Observations
- GRB 080822B, Swift-BAT refined analysis
- SGR 0501+4516: Astrotel-Caucasus optical observations
- SGR 0501+4516: UKIRT detection of possible infra-red counterpart
- SGR 0501+4516: WSRT Radio Observations
- Trigger 321551: Continued Large Flaring of SGR 0501+4516
- SGR 0501+4516: optical observations
- Swift Trigger 321481: A Large Flare from SGR 0501+4516
- SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
- Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
- Third event from SGR 0501+4516
- GRB 080822 (SGR 0501+4516): archival optical observations
- New Soft Gamma Repeater 0501+4516 was GRB 080822
- GRB 080822: Swift detection of a short burst
- GRB 080810: Konus-Wind and Swift/BAT joint spectral analysis
- GLAST Burst Monitor detection of GRB 080810
- GRB 080810: Swift-XRT Team refined analysis
- GRB 080810, Swift-BAT refined analysis