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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"

613 results found.

  1. LIGO/Virgo S190828j: No counterpart candidates in KAIT observations
  2. Integral GRB190828.78 Global MASTER-Net observations report
  3. LIGO/Virgo S190814bv: No candidates found in J-GEM follow-up observations
  4. LIGO/Virgo S190728q: Coverage and upper limits from MAXI/GSC observations
  5. LIGO/Virgo S190718y: No counterpart candidates in CNEOST
  6. Fermi trigger No 585007213 Global MASTER-Net observations report
  7. Fermi trigger No 584264100 Global MASTER-Net observations report
  8. LIGO/Virgo S190706ai: No counterpart candidates in KAIT observations
  9. Swift GRB190631. Global MASTER-Net observations report
  10. LIGO/Virgo S190521r: CNEOST follow-up observations
  11. Fermi GRB190520.6 Global MASTER-Net observations report
  12. LIGO/Virgo S190517h: CALET Observations
  13. LIGO/Virgo S190517h: INTEGRAL prompt observation
  14. LIGO/Virgo S190517h: INTEGRAL/SPI-ACS prompt observation
  15. LIGO/Virgo S190510g: J-GEM optical/NIR follow-up observations
  16. LIGO/Virgo S190412m: Further J-GEM optical/NIR observations
  17. GRB 190427A, Swift-BAT refined analysis
  18. LIGO/Virgo S190426c: CNEOST Optical Observations
  19. LIGO/Virgo S190425z: CNEOST Optical Observations
  20. LIGO/Virgo S190426c: SAO optical observation
  21. Fermi GRB190415.17 Global MASTER-Net observations report
  22. MAGIC follow-up of the X-ray flares of LS I +61�303 dete
  23. Swift detection of LS I +61 303
  24. IceCube-190221A: Swift-XRT Follow-up Observations
  25. GRB 190203A: MASTER OT detection
  26. Konus-Wind observation of GRB 190114C
  27. SWIFT GRB190106.57 Global MASTER-Net OT detection
  28. GRB 181126A: Swift/UVOT Upper Limits
  29. GRB 181027A: Fermi GBM detection
  30. GRB 181020A: Swift-XRT refined Analysis
  31. GRB 181010A: REM optical and NIR afterglow detection
  32. Konus-Wind observation of GRB 180828A
  33. GRB 180728B: MASTER optical observations short GRB IPN error box
  34. GRB 180728B: Fermi GBM detection
  35. GRB 180728A: MASTER OT (= new object) detection
  36. GRB 180722A: MASTER second inspection
  37. GRB 180720B: MASTER Global Net OT observations
  38. FRB 180714: MASTER optical inspection of the Fast Rado Burst Transient
  39. GRB 180718A: Fermi GBM detection
  40. Konus-Wind observation of GRB 180623A
  41. GRB 180623A: Swift detection of a burst
  42. GRB 180618A: MASTER OT observation (a short GRB with extended emission)
  43. GRB 180605A: Fermi GBM observation
  44. Konus-Wind observation of GRB 180523A
  45. GRB 180504A: Swift-BAT refined analysis
  46. Konus-Wind observation of GRB 180427A
  47. Konus-Wind observation of GRB 180316A
  48. GRB 180325A: Swift-XRT refined Analysis
  49. GRB 180224A: Swift/UVOT Detection
  50. Konus-Wind observation of GRB 180111A
  51. GRB 180113A: Swift-BAT refined analysis
  52. GRB 180102A: Swift-BAT refined analysis
  53. IceCube-171106A: Konus-Wind upper limits
  54. GRB 171209A: Swift-BAT refined analysis
  55. GRB 171112A: MAXI/GSC detection
  56. IceCube-171106A: Swift Observations
  57. GRB 171027A, Swift-BAT refined analysis
  58. Swift trigger 781740: Further analysis from Swift and Fermi/GBM
  59. Numerous Fermi-GBM Subthreshold Notices are due to Swift J0243.6+6
  60. Swift Trigger 775946 is a Galactic transient, not GRB 171003
  61. GRB 171003A: LT early optical observations
  62. GRB 170903A: Swift-BAT refined analysis
  63. Konus-Wind observation of GRB 170822A
  64. LIGO/Virgo G298048: ATCA observations of candidate host galaxies
  65. Konus-Wind observation of GRB 170728B
  66. GRB 170714A, Swift-BAT refined analysis
  67. Fermi GBM Detection of possible burst from AXP 4U 0142+61
  68. GRB 170710B: Fermi GBM observation
  69. Konus-Wind observation of GRB 170705A
  70. LIGO/Virgo G268556: optical observations and classification of Pan-STARRS1 transients
  71. GRB 170524A: Swift-BAT refined analysis
  72. Swift trigger 748858: Swift BAT, XRT, and UVOT refined analysis
  73. GRB 170405A: Swift detection of a burst with an optical counterpart
  74. LIGO/Virgo G270580: optical observations and classification of PS and MASTER sources
  75. LIGO/Virgo G275697: Updated localization from LIGO data
  76. LIGO/Virgo G275697: Swift-XRT sources
  77. Konus-Wind observation of GRB 170206A
  78. LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients
  79. LIGO/Virgo G268556: Pan-STARRS1 observations and summary of transient sources
  80. LIGO/Virgo G268556: GWAC_F60B (60cm) follow-up two events of EWE001 and EWE002
  81. LIGO/Virgo G268556/GW170104: Asiago Observations
  82. LIGO/Virgo G268556: ATLAS17aeu - an unusual transient within the skymap
  83. GRB 161220A: Swift-BAT refined analysis
  84. GRB 161214A: fading optical afterglow candidate with the LT
  85. Konus-Wind observation of GRB 161202A
  86. GRB 161113A: Swift/UVOT Upper Limits
  87. GRB 161109A: Swift-XRT observations
  88. Konus-Wind observation of GRB 161020B
  89. GRB 161004A: Swift-BAT refined analysis
  90. GRB 160927A: Swift-BAT refined analysis
  91. GRB 160821B: Fermi GBM Detection
  92. IPN Triangulation of GRB 160720A
  93. GRB 160629A: SAO RAS independent OT detection
  94. GRB 160625B CALET Gamma-Ray Burst Monitor detection
  95. Konus-Wind observation of GRB 160625B
  96. Konus-Wind observation of GRB 160530A
  97. Konus-Wind observation of GRB 160521B
  98. SGR 1935+2154: AbAO optical upper limit
  99. GRB 160504A: Swift detection of a burst
  100. GRB 160424A: Swift-BAT refined analysis

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