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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.

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

16152 results found.

  1. GRB 150728A: Continued RATIR Optical Observations
  2. GRB 150728A: TSHAO optical observations
  3. GRB 150728A: RATIR Optical Observations
  4. GRB 150727A: Continued RATIR Optical Observations - Fading
  5. GRB 150728A: AAO optical observations
  6. GRB 150728A: Swift/UVOT Upper Limits
  7. GRB 150727A: RATIR Optical Observations
  8. GRB 150727A: Watcher optical upper limit
  9. GRB 150724B: Continued RATIR Optical Observations
  10. GRB 150727A: Swift detection of a burst with an optical counterpart
  11. GRB 150724B: RATIR Optical Observations
  12. Swift 650221/IGR J00291+5934: Liverpool Telescope observations
  13. Swift Trigger 650221 / IGR J00291+5934: MASTER-IAC OT observations
  14. Swift IGR J00291+5934: MASTER Optical flare detection
  15. GRB 150724A: Swift/UVOT Upper Limits
  16. SGR 1E 1841-045 (Swift trigger 649113): Terskol upper limit
  17. GRB 150722A: Swift/UVOT Upper Limits
  18. GRB 150720A: Swift/UVOT Upper Limits
  19. GRB 150716A: KAIT Optical Upper Limit
  20. GRB 150711A: Burakan-ISON optical observations
  21. GRB 150716A: Swift/UVOT Upper Limits
  22. GRB 150716A: Continued RATIR Optical Observations
  23. GRB 150716A: P60 Candidate Optical Afterglow
  24. GRB 150716A: RATIR Optical Observations
  25. GRB 150711A: Swift/UVOT Upper Limits
  26. GRB 150711A: Observations from the 2.5m NOT
  27. GRB 150710A: Swift/UVOT Upper Limits
  28. GRB 150702A: MASTER-SAAO inspection
  29. V404 Cyg activity (Swift, Fermi, INTGRAL, KONUS, MAXI detection): optical observations in TSHAO, Khureltogot, and AAO
  30. GRB 150627A: MASTER-SAAO OT Detection
  31. GRB 150627A: Swift/UVOT Detection
  32. GRB 150626B: Swift/UVOT Upper Limits
  33. GRB 150626B: NOT optical upper limits
  34. GRB 150626B: MASTER observations
  35. GRB 150626A: Swift/UVOT Upper Limits
  36. GRB 150616A: Watcher optical upper limit
  37. GRB 150616A: Swift/UVOT Upper Limits
  38. V404 Cyg outburst (Swift trigger 643949 ): TSHAO optical observations
  39. Optical follow-up of Swift trigger on V404 Cyg
  40. GRB 150608A: MITSuME Akeno optical upper limits
  41. GRB150607A: AAO and CrAO optical observations
  42. GRB150607A: Discovery Channel Telescope Optical Observations
  43. GRB 150607A: NOT optical observations
  44. GRB 150607A: Swift detection of a burst with an optical counterpart
  45. GRB 150518A: possible SN observations
  46. GRB 150530A: RATIR Optical Observations
  47. GRB 150530A: Swift/UVOT Upper Limits
  48. GRB 150527A: MITSuME Okayama upper limits
  49. GRB 150527A: Swift/UVOT Upper Limits
  50. GRB150527A: REM - NIR afterglow
  51. GRB 150523A: Swift/UVOT Detection
  52. GRB 150523A: LCOGT FTS afterglow confirmation
  53. GRB 150523A: LCOGT Cerro-Tololo optical afterglow candidate
  54. GRB 150518A: Continued RATIR optical observations
  55. GRB 150518A: MITSuME Akeno Optical observation
  56. GRB 150518A: Mondy optical observations
  57. GRB 150518A: AMI 15 GHz detection of possible radio counterpart
  58. GRB 150518A: MASTER-net before, early and after optical stereoscopic observations with possible MP discovery inside MAXI error box
  59. GRB 150518A: SAO RAS optical observations
  60. GRB 150518A: VLT/X-shooter redshift of the likely host galaxy
  61. GRB 150518A: RATIR optical observations
  62. GRB 150518A: GMG observation
  63. GRB 150518A: Xinglong2.16m optical afterglow detection
  64. GRB 150514A: VLT/X-shooter redshift
  65. GRB 150512A: CrAO optical observations
  66. GRB 150512A: iPTF Optical Observations
  67. GRB 150424A: 9.8 GHz VLA detection
  68. GRB 150423A: GMG observation limit
  69. GRB 150423A: Chandra X-ray Observation
  70. GRB 150430A: Swift/UVOT Upper Limits
  71. GRB 150428B: Swift/UVOT Upper Limits
  72. GRB 150428A: Swift/UVOT Upper Limits
  73. GRB 150413A: CrAO optical observations
  74. GRB 150428C: MASTER-net automatic optical inspection
  75. GRB 150428B: MASTER-net prompt optical observation
  76. GRB 150428A: MASTER-net early optical observation
  77. GRB 150428A: Danish1.56m optical observations
  78. GRB 150428A: RATIR optical observations
  79. GRB 150423A: MITSuME Akeno Optical observation
  80. GRB 150424A: RATIR Observations
  81. GRB 150424A: 10.4m GTC spectroscopy
  82. GRB 150424A: GROND detects strong fading
  83. GRB 150424A: NOT optical observations
  84. GRB 150423A: VLT/X-shooter spectroscopy and tentative redshift
  85. GRB 150423A: Continued RATIR optical afterglow monitoring
  86. GRB 150424A: Swift/UVOT Observations
  87. GRB 150423A: TSHAO optical observations
  88. GRB 150424A: Keck detection of optical afterglow
  89. GRB 150423A: Keck redshift of neighboring galaxy
  90. GRB 150423A: MITSuME Okayama upper limits
  91. GRB 150423A: Swift/UVOT Upper Limits
  92. GRB 150423A: VLT detection
  93. GRB 150423A: RATIR optical afterglow monitoring
  94. GRB 150423A: Keck optical afterglow confirmation
  95. GRB 150423A: KAIT Optical Upper Limit
  96. GRB 150413A: Swift-XRT observations
  97. GRB 150413A: RTT150 optical observations
  98. GRB 150413A: ISON-Ussuriysk optical observations
  99. GRB 150413A: MITSuME Akeno Optical observation
  100. GRB 150413A: SAO RAS observations

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