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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"

16277 results found.

  1. GRB 150616A: Swift/UVOT Upper Limits
  2. V404 Cyg outburst (Swift trigger 643949 ): TSHAO optical observations
  3. Optical follow-up of Swift trigger on V404 Cyg
  4. GRB 150608A: MITSuME Akeno optical upper limits
  5. GRB150607A: AAO and CrAO optical observations
  6. GRB150607A: Discovery Channel Telescope Optical Observations
  7. GRB 150607A: NOT optical observations
  8. GRB 150607A: Swift detection of a burst with an optical counterpart
  9. GRB 150518A: possible SN observations
  10. GRB 150527A: Continued RATIR Observations
  11. GRB 150530A: RATIR Optical Observations
  12. GRB 150530A: Swift/UVOT Upper Limits
  13. GRB 150527A: MITSuME Okayama upper limits
  14. GRB 150527A: Swift/UVOT Upper Limits
  15. GRB150527A: REM - NIR afterglow
  16. GRB 150523A: Swift/UVOT Detection
  17. GRB 150523A: LCOGT FTS afterglow confirmation
  18. GRB 150523A: LCOGT Cerro-Tololo optical afterglow candidate
  19. GRB 150518A: Continued RATIR optical observations
  20. GRB 150518A: MITSuME Akeno Optical observation
  21. GRB 150518A: Mondy optical observations
  22. GRB 150518A: AMI 15 GHz detection of possible radio counterpart
  23. GRB 150518A: MASTER-net before, early and after optical stereoscopic observations with possible MP discovery inside MAXI error box
  24. GRB 150518A: SAO RAS optical observations
  25. GRB 150518A: VLT/X-shooter redshift of the likely host galaxy
  26. GRB 150518A: RATIR optical observations
  27. GRB 150518A: GMG observation
  28. GRB 150518A: Xinglong2.16m optical afterglow detection
  29. GRB 150514A: VLT/X-shooter redshift
  30. GRB 150512A: CrAO optical observations
  31. GRB 150512A: iPTF Optical Observations
  32. GRB 150424A: 9.8 GHz VLA detection
  33. GRB 150423A: GMG observation limit
  34. GRB 150423A: Chandra X-ray Observation
  35. GRB 150430A: Swift/UVOT Upper Limits
  36. GRB 150428B: Swift/UVOT Upper Limits
  37. GRB 150428A: Swift/UVOT Upper Limits
  38. GRB 150413A: CrAO optical observations
  39. GRB 150428C: MASTER-net automatic optical inspection
  40. GRB 150428B: MASTER-net prompt optical observation
  41. GRB 150428A: MASTER-net early optical observation
  42. GRB 150428A: Danish1.56m optical observations
  43. GRB 150428A: RATIR optical observations
  44. GRB 150423A: MITSuME Akeno Optical observation
  45. GRB 150424A: RATIR Observations
  46. GRB 150424A: 10.4m GTC spectroscopy
  47. GRB 150424A: GROND detects strong fading
  48. GRB 150424A: NOT optical observations
  49. GRB 150423A: VLT/X-shooter spectroscopy and tentative redshift
  50. GRB 150423A: Continued RATIR optical afterglow monitoring
  51. GRB 150424A: Swift/UVOT Observations
  52. GRB 150423A: TSHAO optical observations
  53. GRB 150424A: Keck detection of optical afterglow
  54. GRB 150423A: Keck redshift of neighboring galaxy
  55. GRB 150423A: MITSuME Okayama upper limits
  56. GRB 150423A: Swift/UVOT Upper Limits
  57. GRB 150423A: VLT detection
  58. GRB 150423A: RATIR optical afterglow monitoring
  59. GRB 150423A: Keck optical afterglow confirmation
  60. GRB 150423A: GROND afterglow candidate
  61. GRB 150423A: KAIT Optical Upper Limit
  62. GRB 150413A: Swift-XRT observations
  63. GRB 150413A: RTT150 optical observations
  64. GRB 150413A: ISON-Ussuriysk optical observations
  65. GRB 150413A: MITSuME Akeno Optical observation
  66. LOAO B, R Observations of GRB150413A
  67. GRB 150413A: GMG observation
  68. GRB 150413A: AMI 15 GHz detection of possible radio counterpart
  69. GRB 150413A: additional P60 observations
  70. GRB 150413A : Virtual Telescope optical observations
  71. GRB 150413A
  72. GRB 150413A: Bassano Bresciano Observatory optical observations
  73. GRB 150413A: T7 and T18 optical observations
  74. GRB150413A, optical observations
  75. GRB 150413A: optical observations
  76. GRB 150413A: redshift determination with the 2.2m CAHA
  77. GRB 150413A: P60 photometry
  78. GRB 150413A: Khureltogot optical observations
  79. GRB 150413A: Nanshan optical and radio follow-ups
  80. GRB 150413A: Khureltogot optical observations
  81. GRB 150407A: optical observations
  82. GRB 150403A: MASTER-net optical observation
  83. GRB 150404A: Fermi GBM detection
  84. Fermi trigger 449861706: MASTER-SAAO possible candidate to OT of Short GRB
  85. GRB 150403A: VLT/X-shooter redshift
  86. GRB 150323C: CrAO optical observations
  87. GRB 150323C: additional optical observations in Mondy
  88. GRB 150323C: Khureltogot optical observations
  89. GRB 150403A: Swift detection of a burst with an optical counterpart
  90. GRB 150402A: RATIR Optical Observations
  91. GRB 141121A: GMG observation
  92. GRB 150323C: possible host galaxy detection
  93. GRB 141212A: GMG observation limit
  94. GRB 141220A: GMG observation limit
  95. GRB 141225A: GMG observation limit
  96. GRB 150120B: GMG observation
  97. GRB 150317A: likely host galaxy detection
  98. GRB 150323B: Khureltogot optical observations
  99. GRB 150323A: AAO optical observations
  100. GRB 150323C: MITSuME Akeno Optical observation

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