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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19139 results found.

  1. GRB 160601A: Discovery Channel Telescope Limits
  2. GRB 160601A: Swift/UVOT Upper Limits
  3. GRB 160601A: GTC observations confirming transient source decay
  4. GRB 160601A: Mondy optical observations, photometry of NOT sources
  5. GRB160601A: Kanata Telescope I- and Ks-bands upper limits
  6. GRB160601A: NOT detection of an afterglow candidate
  7. GRB 160601A: Mondy optical observations
  8. GRB 160601A: MITSuME Okayama Ks-band upper-limit
  9. GRB 160530A: Swift follow-up and X-ray afterglow candidate
  10. GRB 160601A: MASTER-Net observations
  11. GRB 160530A: discovery with the Compton Spectrometer and Imager
  12. GRB 160530A: Tiled Swift observations
  13. GRB 160525B: Swift/UVOT Detection
  14. GRB 160521B: Swift-XRT afterglow detection
  15. GRB 160521B: Theoretical estimate of the redshift and urgent need for further x-ray observations
  16. GRB 160425A: SMARTS late-time observations
  17. GRB 160327A: 15 GHz upper limits from AMI
  18. GRB 160321A: 15 GHz upper limits from AMI
  19. GRB 160314A: 15 GHz upper limits from AMI
  20. GRB 160313A: 15 GHz upper limits from AMI
  21. GRB 160521B: Swift/UVOT Upper Limits
  22. GRB 160521B: Swift-XRT observations
  23. GRB 160521B: Swift ToO observations
  24. GRB 160509A: Further VLA Observations
  25. GRB 160509A MASTER-NET observations
  26. GRB 160509A: non-observation of VHE emission with HAWC
  27. GRB 160509A: Further Swift/UVOT Observations
  28. GRB 160509A Gemini North redshift
  29. GRB 160509A: DCT Imaging / Afterglow Confirmation
  30. GRB 160509A: VLA Detection
  31. GRB 160509A: Swift/UVOT Upper Limit
  32. GRB 160509A Gemini North candidate afterglow
  33. GRB 160509A: optical observations
  34. GRB 160509A: Swift-XRT afterglow detection
  35. GRB 160509A: Preliminary XRT positon
  36. GRB 160509A: Tiled Swift observations
  37. GRB 160509A: Fermi-LAT prompt detection of a very bright burst
  38. GRB 160506A: TAROT La Silla observatory optical observations
  39. GRB 160506A: IRSF upper limits
  40. GRB 160506A: Swift/UVOT Upper Limits
  41. GRB 160506A: GROND upper limits
  42. IceCube-160427A: iPTF Observations
  43. GRB 160504A: RATIR Optical and NIR Observations
  44. GRB 160504A: Swift/UVOT Upper Limits
  45. GRB160504A: Gemini NIR Observations
  46. GRB 160504A: Bassano Bresciano Observatory upper limits
  47. GRB 160504A: TAROT Calern observatory optical observations
  48. ICECUBE-160427A : Pan-STARRS imaging and optical transients in the field
  49. GRB 160501A: SMARTS optical/IR observations
  50. VERITAS rapid follow-up observations of IceCube event 160427A
  51. GRB 160501A: GROND Upper limits
  52. GRB 160501A: UKIRT near-IR upper limits
  53. GRB 160501A: Swift/UVOT Upper Limits
  54. GRB 160501A: RATIR Optical and NIR Observations
  55. GRB 160501A: TAROT Calern observatory optical observations
  56. GRB 160501A MASTER-NET early observations
  57. GRB 160501A: NOT optical and NIR observations
  58. IceCube-160427A: Fermi GBM Observations
  59. MASTER search for counterpart to the IceCube event 67093193 (run 127853)
  60. Archival observations by HAWC of IceCube HESE event of April 27, 2016
  61. GRB 160422A: XRT Afterglow Confirmation
  62. GRB 160425A: Swift/UVOT Detection
  63. GRB 160425A: Skynet PROMPT-CTIO observations of the optical afterglow
  64. GRB 160425A: SMARTS optical/IR observations
  65. GRB 160325A: Skynet PROMPT-CTIO observations of the optical afterglow
  66. GRB 160422A: GROND NIR afterglow detection
  67. GRB 160425A MASTER notices: possible host galaxy in the optical error-box
  68. GRB 160425A VLT/X-shooter redshift
  69. GRB 160425A: GROND observation
  70. GRB 160422A: Swift/UVOT Afterglow Confirmation
  71. GRB 160425A : MASTER earlier optical observations
  72. GRB 160424A - XRT position uncertain
  73. GRB 160424A: Swift-XRT observations
  74. GRB 160422A: Swift-XRT afterglow detection
  75. GRB 160422A: Swift/UVOT Candidate Afterglow
  76. GRB 160422A: Swift ToO observations
  77. GRB 160417A: GMG observations
  78. GRB 160417A: Swift/UVOT Detection
  79. GRB 160417A: iTelescope T11 optical observations
  80. GRB 160417A: KAIT optical afterglow confirmation
  81. GRB 160412A: GROND upper limits
  82. GRB 160411A - Gemini-S afterglow candidate
  83. GRB 160410A: SMARTS optical/IR observations
  84. LIGO Virgo G211117: Additional MWA Observations
  85. GRB 160410A: TLS Tautenburg observations
  86. GRB 160412A: Swift/UVOT Upper Limits
  87. GRB 160410A: JCMT SCUBA-2 sub-mm observation
  88. GRB 160409A: Swift-XRT observations
  89. GRB 160410A: further NOT optical observations
  90. GRB 160409A: Swift ToO observations
  91. GRB 160410A: NOT observations of the afterglow
  92. GRB 160408A: 6.0 GHz VLA upper limit
  93. GRB 160411A: Gemini-S optical observations
  94. GRB 160411A: GROND Optical/NIR upper limits
  95. GRB 160411A: Swift/UVOT Upper Limits
  96. GRB 160410A: UKIRT near-IR upper limits
  97. GRB 160410A: TAROT La Silla observatory early optical observations
  98. GRB 160411A: MASTER-NET early optical observations.
  99. GRB 160411A: Swift-XRT observations
  100. GRB 160410A: GMG observation

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