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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.

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

21770 results found.

  1. GRB 120328A: MITSuME Ishigakijima Optical Upper Limits
  2. GRB 120326A: MITSuME Ishigakijima Optical Observation at 2 days afterthe burst
  3. GRB 120327A: MITSuME Ishigakijima Optical Upper Limits at 1 day afterthe burst
  4. Swift trigger 518853: MASTER-ICATE possible OT
  5. Trigger 518853: Swift detection of a probable Galactic transient
  6. GRB 120328B: Fermi-LAT Observations
  7. GRB 120327A: Zadko optical observations
  8. GRB 120328A: Swift/UVOT Upper Limits
  9. GRB 120328A: Swift-XRT refined Analysis
  10. Konus-Wind observation of GRB 120328B
  11. IPN Triangulation of GRB 120328B (long/intense)
  12. GRB 120327A: MITSuME Ishigakijima Optical Observation
  13. GRB 120326A: MITSuME Ishigakijima Optical Observation
  14. GRB 120328A: Enhanced Swift-XRT position
  15. GRB 120328A: TAROT La Silla observatory optical observations
  16. Skynet/PROMPT observations of GRB120328A
  17. GRB 120328A: Swift detection of a burst
  18. GRB 120327A afterglow detection
  19. GRB 120326A: PAIRITEL NIR Observations
  20. GRB 120326A: Bassano Bresciano Observatory optical observations
  21. GRB 120327A: Swift/UVOT further analysis
  22. GRB 120326A : SMA submm observation
  23. GRB 120327A: Enhanced Swift-XRT position
  24. GROND observations of GRB 120327A
  25. GRB 120327A: REM NIR and optical observations
  26. Skynet/PROMPT observations of GRB120327A
  27. GRB 120327A: TAROT La Silla observatory optical detection
  28. GRB 120327A: Swift detection of a burst with an optical counterpart
  29. GRB 120326A : LOT optical observation
  30. GRB 120323A: MASTER follow up observations
  31. GRB 120326A: Swift/UVOT Detection
  32. GRB 120326A: Enhanced Swift-XRT position
  33. Skynet/Dolomiti Observations of GRB120326A
  34. GRB 120326A: TAROT Calern observatory afterglow optical detection
  35. GRB 120326A: ROTSE-III Optical Limits
  36. GRB 120326A: Swift detection of a burst
  37. GRB 120323A: Fermi LAT observations
  38. Konus-Wind observation of GRB 120323A
  39. IPN Triangulation of GRB 120323A (short/very intense)
  40. Konus-Wind observation of GRB 120324A
  41. GRB 120324A: GROND observations
  42. GRB 120324A: CQUEAN rizY Observation
  43. GRB 120324A: Swift-BAT refined analysis
  44. GRB 120324A: Swift/UVOT Upper Limits
  45. GRB 120324A: TAROT La Silla observatory optical observations
  46. GRB 120324A: Enhanced Swift-XRT position
  47. GRB 120324A: Swift detection of a burst
  48. GRB 120316A : Suzaku WAM observation of the prompt emission
  49. GRB 120320A: Zadko optical observations
  50. GRB 120316A: Fermi-GBM and Fermi-LAT Observations
  51. GRB 120229A: Magellan observations and limit on an optical afterglow
  52. GRB 120320A: Swift/UVOT Upper Limits
  53. GRB 120320A: MITSuME Okayama Optical upper limits
  54. GRB 120320A , optical observations
  55. GRB 120320A: BOOTES-4 optical upper limit
  56. GRB 120320A: Gemini-N and UKIRT observations
  57. GRB 120320A: Enhanced Swift-XRT position
  58. Konus-Wind observation of GRB 120316A
  59. IPN Triangulation of GRB 120316A
  60. GRB 120320A: MASTER optical observations
  61. GRB 120320A: Swift detection of a burst
  62. Trigger 517876 is a Swift detection of GX 5-1
  63. GRB 120302A: Swift XRT refined analysis
  64. GRB 120312A: CrAO optical upper limit
  65. GRB 120312A: Gemini and UKIRT imaging
  66. GRB 120311A: Optical follow-up
  67. GRB 120311B: Optical follow-up
  68. GRB 120311A: C88 optical limits
  69. GRB 120312A: Swift/UVOT Upper Limits
  70. GRB 120312A: MASTER-NET optical observations
  71. GRB 120312A: WHT candidate afterglow
  72. GRB 120312A: NOT observations
  73. GRB 120312A: Swift-XRT refined Analysis
  74. GRB 120311B: C88 optical limits
  75. GROND observations of GRB 120311A
  76. GRB 120311B: Swift/UVOT Upper Limits
  77. GRB 120311B: MITSuME Okayama Optical upper limits
  78. GRB 120311B: Faulkes Telescope North observations
  79. GRB 120311B: Enhanced Swift-XRT position
  80. GRB 120311B: Swift-BAT refined analysis
  81. GRB 120311B: Swift-XRT observations
  82. GRB 120311A: Swift/UVOT Upper Limits
  83. GRB 120311A: Enhanced Swift-XRT position
  84. GRB 120311A: Swift-XRT observations
  85. GRB 120308A: RTT150 optical observations
  86. GRB 120302A: RTT150 optical observations
  87. GRB 120308A: 1.23m CAHA I-band observations
  88. GRB 120308A: Further PAIRITEL NIR Observations
  89. GRB120308A: MITSuME Ishigakijima Optical Upper Limits
  90. GRB 120308A: Swift/UVOT Detection
  91. GRB 120308A: Enhanced Swift-XRT position
  92. GRB 120308A: IAC80 I-band observations
  93. GRB 120308A: PAIRITEL NIR observations
  94. GRB 120308A: confirmation of the optical afterglow
  95. GRB 120308A: Swift detection of a burst
  96. GRB 120305A: D50 optical limits
  97. GRB 120302A: Swift-BAT refined position and a possible XRT and UVOT counterpart
  98. GRB 120305A: Swift/UVOT Upper Limits
  99. GRB 120305A: Enhanced Swift-XRT position
  100. GRB 120305A: MASTER-NET early optical observations

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