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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"

15248 results found.

  1. GRB 160504A: RATIR Optical and NIR Observations
  2. GRB 160503A: Fermi GBM observation
  3. GRB 160503A: Fermi-LAT detection
  4. VERITAS rapid follow-up observations of IceCube event 160427A
  5. GRB 160501A: GROND Upper limits
  6. IceCube-160427A: Fermi GBM Observations
  7. ICECUBE-160427A neutrino candidate event: updated direction information
  8. Archival observations by HAWC of IceCube HESE event of April 27, 2016
  9. Fermi/LAT search for counterpart to the IceCube event 67093193 (run 127853)
  10. GRB 160422A: XRT Afterglow Confirmation
  11. GRB 160425A: Swift/UVOT Detection
  12. GRB 160425A: Skynet PROMPT-CTIO observations of the optical afterglow
  13. GRB 160425A: Swift-BAT refined analysis
  14. GRB 160325A: Skynet PROMPT-CTIO observations of the optical afterglow
  15. GRB 160422A: GROND NIR afterglow detection
  16. GRB 160425A: GROND observation
  17. Konus-Wind observation of GRB 160424A
  18. LIGO/Virgo G197392 / LVT151012: Identification of a GW CBC Candidate
  19. GRB 160424A: Fermi GBM observation
  20. GRB 160422A: Fermi GBM observation
  21. GRB 160422A: Swift ToO observations
  22. GRB 160422A: Fermi-LAT Detection
  23. GRB 160419A: Fermi GBM detection
  24. GRB 160417A: Swift/UVOT Detection
  25. GRB 160417A: MITSuME Okayama upper limits
  26. GRB 160417A: KAIT optical afterglow confirmation
  27. LIGO/Virgo G211117: EWE for NOWT of 12 days follow-up of northern sky
  28. GRB 160412A: GROND upper limits
  29. Konus-Wind observation of GRB 160409A
  30. GRB 160410A: TLS Tautenburg observations
  31. GRB 160409A: Swift ToO observations
  32. GRB 160411A: GROND Optical/NIR upper limits
  33. GRB 160411A: Fermi GBM detection
  34. Konus-Wind observation of GRB 160410A (short/hard)
  35. GRB 160411A: MASTER-NET early optical observations.
  36. GRB 160410A: Skynet PROMPT-CTIO observations of the optical afterglow
  37. GRB 160410A: GROND optical detection
  38. GRB 160408A: TLS Tautenburg observations
  39. GRB 160408A: Fermi GBM detection
  40. GRB 160406A: Fermi GBM observation
  41. GRB 160401A: Swift ToO observations
  42. GRB 160401A: a long GRB detected by INTEGRAL
  43. LIGO/Virgo G211117: LOFAR follow-up
  44. GRB 160327A: Early RAPTOR Limits
  45. Konus-Wind observation of GRB 160325A
  46. GRB 160327A: KAIT optical afterglow confirmation
  47. GRB 160327A: Mondy optical upper limit
  48. GRB 160325A: GROND Upper Limits
  49. GRB 160325A: Further Swift/UVOT Observations
  50. GRB 160325A: afterglow confirmation
  51. GRB160325A Swift/UVOT Detection
  52. GRB 160325A: Fermi-LAT detection
  53. LIGO/Virgo G211117: CALET GBM Observations
  54. Swift detects GX 301-2 in very high state
  55. IPN Triangulation of GRB 160310A
  56. LIGO/Virgo G211117: EWE for NOWT follow-up of northern sky
  57. GRB 160310A: A further Swift-XRT observation, no afterglow detected
  58. GRB 160314A: Continued RATIR Optical and NIR Observations
  59. GRB 160314A: GROND optical/NIR observations
  60. GRB 160314A: ISON-Ussuriysk optical upper limit, updated photometry and correction of GCN 19184
  61. GRB 160314B: Fermi GBM observation
  62. GRB 160314B: Fermi-LAT detection
  63. GRB 160314A: RATIR Optical and NIR Observations
  64. LIGO/Virgo G194575: EWE for NOWT follow-up of northern sky
  65. GRB 160228A: GROND afterglow confirmation and X-shooter host candidate redshift
  66. Konus-Wind observation of GRB 160310A (possible ultra-long GRB?)
  67. GRB 160310A: LCOGT-SAAO optical upper limits
  68. GRB 160310A: Fermi GBM observation
  69. GRB 160310A: Swift ToO observations
  70. GRB 160310A: Fermi-LAT detection
  71. LIGO/Virgo G211117: HAWC follow-up of northern sky
  72. Trigger 677981: Swift detection of IGRJ17091-3624
  73. GRB 160303A: Continued optical monitoring from NOT
  74. GRB160303A: further GROND observations
  75. GRB 160303A: Continued RATIR Optical and NIR Observations
  76. GRB 160303A: GROND Optical Detection
  77. GRB 160303A: McDonald 2.1m CQUEAN Detection
  78. GRB 160303A: LCOGT-FTN optical observations
  79. GRB 160227A: LOAO 1.0m optical detection
  80. GRB 160228A: GROND Afterglow Candidate
  81. GRB 160227B: Fermi GBM detection
  82. GRB 160227A: NOT redshift
  83. GRB 160225B: Fermi GBM detection
  84. GRB 160225A: RATIR Optical and NIR Observations
  85. GRB 160225A: Swift/UVOT Upper Limits
  86. GRB 160225A: MITSuME Okayama Optical Observation
  87. GRB 160223A: Swift-XRT afterglow detection
  88. GRB 160221A: Swift-XRT afterglow detection
  89. Konus-Wind observation of GRB 160219A
  90. GRB 160223A: Fermi GBM observation
  91. GRB 160223B: Fermi GBM observation
  92. GRB 160223B: Swift ToO observations
  93. GRB 160223B: A long GRB detected by INTEGRAL
  94. GRB 160221A: Fermi GBM observation
  95. GRB 160220B: Further GROND Observations
  96. GRB 160221A: Swift ToO observations
  97. GRB 160221A: A long GRB detected by INTEGRAL
  98. Konus-Wind observation of GRB 160220B
  99. GRB 160220B: GROND Observations
  100. GRB 160219A: Fermi GBM detection

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