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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').
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"

2853 results found.

  1. GRB 180620A: Swift-BAT refined analysis
  2. GRB 180618A: MASTER OT observation (a short GRB with extended emission)
  3. GRB 180605A: Fermi GBM observation
  4. IPN Triangulation of GRB 180523A
  5. GRB 180510B: Swift detection of a burst with an optical counterpart
  6. GRB 180411A: Swift-BAT refined analysis
  7. Konus-Wind observation of GRB 180404C
  8. IPN Triangulation of GRB 180404C (long)
  9. GRB 180404C CALET Gamma-Ray Burst Monitor detection
  10. Fermi GBM triggers 544628550/180405571, 544542853/180404579, 544531428/180404447 are not GRBs
  11. GRB 180404A: MASTER-OAFA OT observation
  12. GRB 180329B: Swift detection of a burst with an optical afterglow
  13. GRB 180324A: Enhanced Swift-XRT position
  14. GRB 180324A: Prompt enhanced Swift-XRT position
  15. GRB 180324A: Swift detection of a burst
  16. IPN Triangulation of GRB 180318A (long)
  17. GRB180316A: MASTER-IAC OT light curve
  18. GRB180316A: MASTER-IAC optical detection
  19. GRB 180205A: Mondy optical observations
  20. Swift J1658.2-4242: Swift BAT and XRT refined analysis
  21. Swift trigger 810300: MASTER-OAFA robotic report
  22. Swift J1658.2-4242 (trigger 810300): Swift-XRT position
  23. Swift Trigger 810300 is a probable new Galactic source: Swift J1658.2-4242
  24. GRB 180205A: Xinglong TNT optical observation
  25. GRB 180111A: Insight-HXMT/HE observation
  26. Konus-Wind observation of GRB 180111A
  27. GRB 180111A CALET Gamma-Ray Burst Monitor detection
  28. GRB 180111A: AGILE/MCAL detection
  29. GRB 180111A: Swift detection of a burst with an optical counterpart
  30. GRB 171205A: MASTER-Net OT recent photometry
  31. Pan-STARRS follow-up of IceCube-171106A
  32. GRB 171126A: Fermi GBM detection
  33. GRB 171108B: Insight-HXMT detection
  34. GRB 171115A: Swift detection of a burst
  35. GRB 171112A: MAXI/GSC detection
  36. IceCube-171106A: Swift Observations
  37. GRB 171010A: afterglow and SN 2017htp optical observations
  38. GRB 171030A: MASTER inspection of the IPN error box of the short GRB.
  39. GRB 171007A: Swift-XRT refined Analysis
  40. GRB 171004A: Swift-BAT refined analysis
  41. LIGO/Virgo G298048: Record of all e-MERLIN results to date on SSS17a
  42. IceCube-170922A: Swift-XRT observations
  43. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  44. LIGO/Virgo G297595: NIR Observations following GW170814
  45. GRB 170911A: MAXI/GSC detection
  46. GRB 170903A: MITSuME Okayama upper limits
  47. LIGO/Virgo G297595: DECam observations of BBH merger region of interest
  48. LIGO/Virgo G299232 ANTARES search (2)
  49. GRB 170830A: MAXI/GSC detection
  50. LIGO/Virgo G299232 TZAC/TAROT observations
  51. LIGO/Virgo G299232: AGILE GRID observations
  52. LIGO/Virgo G299232 ANTARES search
  53. LIGO/Virgo G298936 TAROT/TZAC observations
  54. LIGO/Virgo G298936: GWFUNC/CNEOST optical observations and an optical transient
  55. LIGO/Virgo G298048: TOROS optical counterpart search
  56. LIGO/Virgo G298048: HSC observations of the OT candidate of G298048
  57. LIGO/Virgo G298048: Subaru HSC follow-up observations
  58. LIGO/Virgo G298048: Galaxy-Targeted Optical Followup With Las Cumbres Observatory
  59. LIGO/Virgo G297595: Subaru Hyper Suprime-Cam follow-up observations
  60. LIGO/Virgo G297595: REM optical/NIR observations
  61. LIGO/Virgo G297595 : MAXI/GSC observations
  62. LIGO/Virgo G297595: Fermi GBM Observations
  63. LIGO/Virgo G297595: AGILE GRID observations
  64. IPN Triangulation of GRB 170805B (short/hard)
  65. GRB 160814A: Lomonosov BDRG gamma ray discovery
  66. GRB 170710B: Fermi GBM observation
  67. GRB 170710B: Swift-XRT and UVOT observations
  68. GRB 170626A: SAO RAS confirmation of OT fading
  69. GRB 170626A: TShAO optical observations
  70. GRB 170626A: SAO RAS possible OT detection
  71. LIGO/Virgo G288732: Pan-STARRS coverage of the Fermi/LAT candidate position
  72. Konus-Wind observation of GRB 170616A
  73. Swift Trigger 756953 is probably not an astrophysical source
  74. Konus-Wind observation of GRB 170607B
  75. GRB 170610A: MAXI/GSC detection
  76. IPN Triangulation of GRB 170607B
  77. GRB 170607B: AstroSat CZTI detection
  78. GRB 170607A: MASTER-Tavrida early OT observations
  79. GRB 170519A: TShAO and AbAO optical observations
  80. Swift Trigger 755873: MASTER Net optical observations
  81. GRB 170531A: MASTER Net job
  82. LIGO/Virgo G268556: optical observations and classification of Pan-STARRS1 transients
  83. LIGO/Virgo G268556/GW170104: Konus-Wind observations
  84. GRB 170524B: MASTER-OAFA observations
  85. IPN Triangulation of GRB 170522B (long/intense)
  86. Konus-Wind observation of GRB 170522A
  87. AXP CXOU J164710.2-455216: Fermi GBM observation
  88. Konus-Wind observation of GRB 170510A
  89. Short GRB 170428A: MASTER-OAFA final reduction of the optical observations
  90. GRB 170428A: Swift detection of a short burst
  91. Swift Trigger 750044 is probably a noise fluctuation
  92. Konus-Wind observation of GRB 170424A
  93. GRB 170412A CALET Gamma-Ray Burst Monitor detection
  94. Konus-Wind observation of GRB 170409A
  95. GRB 170409A: Fermi GBM Observation
  96. Fermi trigger 512347439/GRB 170327A: MASTER-SAAO possible OT detection
  97. GRB 170331A: Swift detection of a burst
  98. Konus-Wind observation of GRB 170320A
  99. GRB 170320A: POLAR Observation
  100. IPN Triangulation of GRB 170320A (long/intense)

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