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"3850 results found.
- GRB 180728A: AstroSat CZTI detection
- GRB 180806.94: MASTER possible OT detection in Fermi GMB trigger 555287944 error box
- GRB 180805B: Enhanced Swift-XRT position
- GRB 180805B: Swift detection of a burst
- Fermi Trigger 554765006: MASTER optical inspection
- GRB 180728B: GOTO optical search over IPN region
- GRB 180728B: MASTER optical observations short GRB IPN error box
- Konus-Wind observation of the bright nearby GRB 180728A
- IPN Triangulation of GRB 180728B (short)
- GRB 180728A: VLT/X-shooter redshift of a nearby energetic GRB
- GRB 180728A: Fermi GBM observation
- GRB 180728A: MASTER OT (= new object) detection
- GRB 180728A: Swift detection of a bright burst
- ANTARES neutrino Alert180713.02: MASTER optical observation
- GRB 180718A: MASTER optical observation
- IceCube-171106A: MASTER optical observation
- GRB 180706A: TSHAO optical observations
- Fermi GBM triggers 552488966/180705548 and 552490104/180705561 are not GRBs
- GRB 180705A: MASTER optical observation
- GRB 180626C: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 551697835)
- IPN Triangulation of GRB 180626B (short)
- Konus-Wind observation of GRB 180620A
- GRB 180611A: AstroSat CZTI detection
- GRB 180529A: AstroSat CZTI detection
- GRB 180614A: MASTER observation
- Konus-Wind observation of GRB 180611A
- GRB 180611A: Fermi GBM observation
- IPN Triangulation of GRB 180611A (long)
- Konus-Wind observation of GRB 180529A
- GRB 180529A: CALET Gamma-Ray Burst Monitor detection
- IPN Triangulation of GRB 180529A (short/hard)
- AGILE/MCAL detection of GRB 180529 and a possible precursor
- IPN Triangulation of GRB 180523A
- GRB 180510A: MITSuME Ishigakijima optical upper limits
- Retraction of IceCube GCN/AMON NOTICE 71165249_130949
- GRB 180407A: Swift detection of a burst
- Konus-Wind observation of GRB 180404B
- GRB 180404B: MASTER-OAFA OT observation
- GRB 180325A: Swift/UVOT Detection
- Konus-Wind observation of GRB 180316A
- GRB 180325A: Swift detection of a burst with an optical counterpart
- GRB 180324A: Swift detection of a burst
- GRB 180316A: Swift-BAT refined analysis
- GRB 180314A: VLT/X-shooter redshift
- GRB 180314A: Swift/UVOT Detection
- GRB 180314A: Enhanced Swift-XRT position
- GRB 180314A: Swift detection of a burst with an optical counterpart
- GRB 180311A, Swift-BAT refined analysis
- GRB 180311A: Enhanced Swift-XRT position
- GRB 180311A: Prompt enhanced Swift-XRT position
- GRB 180311A: Swift detection of a burst
- GRB 180210A: Insight-HXMT/HE observation
- GRB180224A: Global MASTER-Net bright OT detection
- GRB 180221B CALET Gamma-Ray Burst Monitor detection
- GRB 180112A: AstroSat CZTI detection
- GRB 180205A: BAO optical observations
- GRB 180205A: AbAO optical observations
- Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
- GRB 180205A: VLT polarimetry
- GRB 180205A: Mondy optical observations
- GRB 180120A: Fermi GBM Detection
- GRB 180112A CALET Gamma-Ray Burst Monitor detection
- IPN Triangulation of GRB 180113B
- GRB 180116A: MAXI/GSC detection
- Konus-Wind observation of GRB 180113A
- GRB 171229A CALET Gamma-Ray Burst Monitor detection
- GRB 171216A: Enhanced Swift-XRT position
- GRB 171216A: Swift detection of a burst
- Swift Trigger 797070 is probably not a GRB
- GRB 171210A: Swift-XRT and UVOT observations
- GRB 171211A: Swift detection of a possibly short burst
- GRB 171205A: iTelescope optical observations
- Swift Trigger 796098 is probably a noise peak near M31
- GRB 171030A: MASTER inspection of the IPN error box of the short GRB.
- GRB 171102B: Swift detection of a burst
- GRB 171030A: Fermi GBM detection
- GRB 171030A: Swift non-localization with BAT, XRT and UVOT
- IPN Triangulation of GRB 171030A (short)
- Swift Triggers 784159 and 784160 are not bursts
- Swift Trigger 783893: LCO 1-m telescope observations
- Swift Trigger 783893 is probably not a GRB
- GRB 171027A: LCO 1-m telescope observations
- GRB 171027A: MASTER-OAFA (Argentina) early prompt optical observations
- IPN Triangulation of GRB 171022A
- Swift trigger 781740: Further analysis from Swift and Fermi/GBM
- Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
- Trigger 780207: Swift triggers again on AXP CXOU J164710.2-455216/PSR J1647-4552
- Trigger 779351: Swift detection of Swift J0243.6+6124
- GRB 171010A: MITSuME Akeno Optical Observation
- LIGO/Virgo G299232: MAGIC Cherenkov Telescopes observations
- LIGO/Virgo G298048: Record of all e-MERLIN results to date on SSS17a
- GRB 170728B: Kottamia R-band observation
- LIGO/Virgo G298048: Summary of Pi of the Sky observations
- LIGO/Virgo G297595: NIR Observations following GW170814
- LIGO/Virgo G299232: Swift-XRT sources
- GRB 170829A: Insight-HXMT detection
- IPN Triangulation of GRB 170904A (long/very bright)
- LIGO/Virgo G297595: DECam observations of BBH merger region of interest
- LIGO/Virgo G298048: Possible Plateau in Ks band revealed by continued Gemini-South observations
- LIGO/Virgo G299232: GRAWITA Asiago optical observations