Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
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"

2810 results found.

  1. Further Chandra observations of GW170817 ~581-583 days since merger
  2. Swift detection of LS I +61 303
  3. Correction: Chandra observations of GW170817 ~581 days since merger
  4. Chandra observations of GW170817 ~581 days since merger
  5. GRB 190206A: AstroSat CZTI detection
  6. GRB 190203A: Swift-BAT refined analysis
  7. GRB 190204A: Swift detection of a burst with a possible optical counterpart
  8. GRB 190202A: LCO-CTIO optical observations
  9. GRB 190129B: DDOTI Detection of the Possible Afterglow and Suggestion of Fading
  10. GRB 190129B: GROND possible host candidate
  11. IceCube-190124A - IceCube observation of a high-energy neutrino candidate event
  12. GRB 190114C: GMRT detection at 1.26GHz
  13. Swift ToO Instructions Update
  14. Swift ToO Website Down
  15. GRB 190114C: RATIR Optical and NIR Detections
  16. GRB 190114C: COATLI Optical Detection
  17. GRB 190114B, Swift-BAT refined analysis
  18. GRB 190114C: SPI-ACS/INTEGRAL extended emission detection
  19. GRB 190114C: Possible host galaxy in Pan-STARRS
  20. GRB 190114B: Swift detection of a burst
  21. GRB 190114A: Possible UVOT Detection
  22. GRB 190106A: optical observations, possible jet break detection
  23. Correction to the GCN circ. 23654 / GRB 190109B: Mondy optical upper limit
  24. GRB 190106A: GMG spectral results
  25. GRB 181228A: possible NOT optical detection
  26. FRB 181228: Global MASTER Net optical inspection
  27. Swift Trigger 878504 is not astrophysical
  28. MASTER: OTs detection during Fermi alert trigger 565936249 early observations
  29. GRB 181201A: VLT/FORS2 tentative spectroscopic redshift
  30. Short-duration GRB 181121.4: MASTER-Tavrida possible OT detection near the PGC galaxy during large Fermi error box inspection
  31. GRB 181123B: Keck near-infrared imaging
  32. GRB 181110A: Kanata 1.5m optical observation
  33. Fermi GRB 181105.31: Global MASTER Net optical observations
  34. GRB 181030A: Swift detection of a burst with a possible optical counterpart
  35. IceCube-181023A - IceCube observation of a high-energy neutrino candidate event
  36. GRB 181020A: Global MASTER Net OT observations
  37. IceCube-181014A - IceCube observation of a high-energy neutrino candidate event
  38. IceCube-180908A - IceCube observation of a high-energy neutrino candidate event
  39. GRB 180828A: Swift detection of a GRB or possible Galactic Transient Swift J1754.9-2548
  40. GRB 180728A: discovery of the associated supernova
  41. Swift Trigger 852625: Swift/BAT/XRT/UVOT observations
  42. GRB 180809B: CALET Gamma-Ray Burst Monitor detection
  43. Swift Trigger 852625: a possible GRB
  44. GRB 180806.94: MASTER possible OT detection in Fermi GMB trigger 555287944 error box
  45. GMRT radio detection of GRB 180720B
  46. GRB 180728B: GOTO optical search over IPN region
  47. GRB 180728B: MASTER optical observations short GRB IPN error box
  48. GRB 180720C: Swift detection of a burst or possible Galactic Transient
  49. GRB 180720B: LCO Haleakala possible bright optical candidate
  50. GRB 180715A: LCO Sutherland possible optical candidate
  51. GRB 180705A: OSN observations
  52. Konus-Wind observation of GRB 180704A
  53. GRB 180703A: LCO Sutherland possible optical candidate
  54. GRB150101B: INTEGRAL prompt gamma-ray signal from a possible GRB170817A-analogue
  55. GRB 180626C : GOTO optical observations
  56. GRB 180626B : GOTO optical observations
  57. GRB 180613A: Possible IR afterglow
  58. GRB 180613A: Possible host galaxy at XRT position, or star
  59. GRB 180529A: CALET Gamma-Ray Burst Monitor detection
  60. AGILE/MCAL detection of GRB 180529 and a possible precursor
  61. Swift Trigger 831888: a possible GRB or Galactic transient
  62. GRB 180510B: Swift detection of a burst with an optical counterpart
  63. Chandra observations of GW170817 reveal a fading afterglow
  64. Chandra observations of GW170817 260 days since merger: first statistically significant evidence for an X-ray decay
  65. GRB 180418A GROND observations
  66. Chandra observations of GRB161219B 400 days after the explosion
  67. Swift Trigger 819301: possible GRB 180329A
  68. GRB 180324A: RATIR Optical Observations and Possible Afterglow Detection
  69. GRB 180316A: RATIR Optical Observations, Possible Re-brightening
  70. GRB 180224A: AbAO optical observations
  71. Swift trigger 811074 (possible GRB 180221A): Swift refined analysis
  72. GRB180221A: MASTER-OAFA optical observations
  73. Swift Trigger 811074: possible GRB 180221A
  74. Trigger 809374: Swift detection of a possible non-burst faint source
  75. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  76. LIGO/Virgo GW170817: Chandra X-ray Emission Continues to Rise ~156 Days Post-Merger
  77. GRB 180120A CALET Gamma-Ray Burst Monitor detection
  78. GRB180111A: Xinglong TNT possible optical detection
  79. GRB 180103A: LCO Sutherland 1-m telescope observations
  80. GRB 171209A: Swift/UVOT Analysis of the burst
  81. GRB 171209A: Swift detection of a burst
  82. LIGO/Virgo G298048: Brightening X-ray Emission from GW170817/GRB170817A/SSS17a
  83. LIGO/Virgo GW170817: Chandra X-ray brightening of the counterpart 108 days since merger
  84. GRB 171205A: Host galaxy photometric properties
  85. Possible blackbody component in the X-ray spectrum of GRB171205A
  86. Pan-STARRS follow-up of IceCube-171106A
  87. GRB 171123A: Swift detection of a burst
  88. GRB 171010A: possible SN component
  89. IceCube-171106A - IceCube observation of a high-energy neutrino candidate
  90. GRB 171030A: MASTER inspection of the IPN error box of the short GRB.
  91. GRB 171103A: Fermi GBM observation
  92. GRB 171010A: VLT spectroscopic identification of the associated SN 2017htp
  93. GRB 171030A: IPN error box through NSs probability merging rate map
  94. Swift trigger 781740: Further analysis from Swift and Fermi/GBM
  95. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  96. Swift trigger 779171 is probably a noise fluctuation
  97. IceCube-171015A - IceCube observation of a high-energy neutrino candidate event
  98. BAT trigger 778435 is not a GRB.
  99. GRB 171013A: Swift detection of a possible burst
  100. GRB 171010A: Swift/UVOT Detection

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov