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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"

16152 results found.

  1. LOAO B, R Observations of GRB150413A
  2. GRB 150413A: GMG observation
  3. GRB 150413A: AMI 15 GHz detection of possible radio counterpart
  4. GRB 150413A: additional P60 observations
  5. GRB 150413A : Virtual Telescope optical observations
  6. GRB 150413A
  7. GRB 150413A: Bassano Bresciano Observatory optical observations
  8. GRB 150413A: T7 and T18 optical observations
  9. GRB150413A, optical observations
  10. GRB 150413A: optical observations
  11. GRB 150413A: redshift determination with the 2.2m CAHA
  12. GRB 150413A: P60 photometry
  13. GRB 150413A: Khureltogot optical observations
  14. GRB 150413A: Nanshan optical and radio follow-ups
  15. GRB 150413A: Khureltogot optical observations
  16. GRB 150407A: optical observations
  17. GRB 150403A: MASTER-net optical observation
  18. GRB 150404A: Fermi GBM detection
  19. Fermi trigger 449861706: MASTER-SAAO possible candidate to OT of Short GRB
  20. GRB 150403A: VLT/X-shooter redshift
  21. GRB 150323C: CrAO optical observations
  22. GRB 150323C: additional optical observations in Mondy
  23. GRB 150323C: Khureltogot optical observations
  24. GRB 150403A: Swift detection of a burst with an optical counterpart
  25. GRB 150402A: RATIR Optical Observations
  26. GRB 141121A: GMG observation
  27. GRB 150323C: possible host galaxy detection
  28. GRB 141212A: GMG observation limit
  29. GRB 141220A: GMG observation limit
  30. GRB 141225A: GMG observation limit
  31. GRB 150120B: GMG observation
  32. GRB 150317A: likely host galaxy detection
  33. GRB 150323B: Khureltogot optical observations
  34. GRB 150323A: AAO optical observations
  35. GRB 150323C: MITSuME Akeno Optical observation
  36. GRB 150220A: Optical observations at Kyiv comet station
  37. GRB 150323C; Konkoly optical observations
  38. GRB 150323B; Konkoly optical observations
  39. GRB 150323A; Konkoly optical observations
  40. GRB 150323C: Mondy optical observations
  41. GRB 150323C: RATIR Optical Afterglow Observations - Errata
  42. GRB 150323C: Swift/UVOT Upper Limits
  43. GRB 150323C: RATIR Optical Afterglow Observations
  44. GRB 150323C : Xinglong TNT optical observation
  45. GRB 150323C: Xingming upper limit
  46. GRB 150323A: KAIT Optical Observations
  47. GRB 150323C: Nanshan optical afterglow detection
  48. GRB 150323C: MASTER-net optical observation
  49. GRB150323A: Swift-UVOT detection of the afterglow
  50. GRB 150323A: Keck redshift
  51. GRB 150314A: GMG observation limit
  52. GRB 150323A: RATIR Optical Afterglow Observations
  53. GRB 150323A: P60 Optical Afterglow Candidate
  54. GRB 150314A: Further VLA observations
  55. GRB 150318A: Skynet PROMPT-CTIO Observations
  56. GRB 150318A: Swift/UVOT Upper Limits
  57. GRB 150317A: RATIR Optical Afterglow Detection
  58. GRB 150317A: NOT optical observations
  59. GRB 150314A: VLA observations
  60. GRB 150314A: Early RAPTOR Detection
  61. GRB 150314A: NOT further optical observations
  62. GRB 150314A: KAIT Optical Observations
  63. GRB 150314A: P60 observations
  64. GRB 150314A: NOT optical observations
  65. GRB 150314A: Swift/UVOT Detection
  66. GRB 150314A: MITSuME Akeno upper limits
  67. GRB 150314A: Skynet Yerkes-41 Observations of the Optical Afterglow
  68. GRB 150314A: Fermi-LAT detection
  69. GRB 150314A: KAIT Optical Candidate
  70. GRB 150222A: CrAO optical observation
  71. GRB150309A: Optical observations at Crni Vrh
  72. GRB 150309A: Swift/UVOT Upper Limits
  73. GRB 150309A: MASTER prompt optical observation
  74. GRB 150309A : Liverpool Telescope observations
  75. GRB 150309A: BOOTES-1 and -2 upper limit
  76. Further UVOT Observations of Swift J0045.2+4151
  77. BAT trigger 633105 (GRB 150301C): NOT r-band upper limit
  78. GRB 150302A: BOOTES-2/TELMA upper limit
  79. GRB 150302A: Mondy optical upper limit
  80. GRB 150302A: Swift/UVOT Upper Limits
  81. GRB 150302A: MITSuME Okayama upper limits
  82. GRB 150301B: Swift/UVOT Observations
  83. GRB 150301B: LCOGT-Sutherland observations
  84. GRB 150302A: KAIT Optical Upper Limit
  85. GRB 150302A: NOT afterglow candidate
  86. GRB 150301B: GROND afterglow observations
  87. GRB 150301A: Swift/UVOT Upper Limits
  88. GRB 150301B: MASTER early OT detection
  89. GRB 150301B: Swift detection of a burst with an optical afterglow
  90. GRB 150222A: Further GROND Observations
  91. GRB 150222A: I-band observations from OSN
  92. GRB 150222A: Swift/UVOT Upper Limits
  93. GRB 150222A: GROND optical afterglow candidate
  94. GRB 150222A: TNG optical observations
  95. GRB 150222A: Mondy optical observations
  96. GRB 150222A: Zadko observatory - Gingin optical observations
  97. GRB 150222A: MASTER early optical observations
  98. Trigger 631747: Swift detection of 4U 0614+09
  99. GRB 150213B: AAO photometry
  100. GRB 150213B: P60 Observations

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