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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').
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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"

21772 results found.

  1. GRB111029A: MITSuME Ishigakijima Optical Upper Limits
  2. GRB 111029A: PAIRITEL NIR Upper Limits
  3. GRB 111029A: Swift/UVOT Upper Limits
  4. GRB 111029A: Enhanced Swift-XRT position
  5. GRB 111029A: optical upper limit
  6. GRB 111029A: ROTSE-III Optical Limits
  7. GRB 111029A: Swift detection of a burst
  8. GRB 111022B: 10.4m GTC z'-band observations
  9. GRB111022B: D50 optical limit
  10. GRB 111020A: Chandra Observation
  11. GRB 111022B: BTA Optical Observations
  12. GRB 111022B: Swift/UVOT upper limits
  13. GRB 111022A: Swift/UVOT Upper Limits
  14. GRB 111016A: optical upper limit
  15. GRB 111022B: NOT observations
  16. GRB 111022B: Enhanced Swift-XRT position
  17. GRB 111022B: MASTER-Net early limit
  18. GRB 111022A: Preliminary UVOT TDRSS Non-Detection
  19. GRB 111022A: MASTER-Net early limit
  20. GRB 111022B: Swift detection of a burst
  21. GRB 111022A: Swift detection of a burst
  22. GRB 111020A: Gemini-South additional observations and limit on an optical afterglow
  23. GRB 111020A: Swift/UVOT Upper Limits
  24. GRB 111020A: Enhanced Swift-XRT position
  25. GRB 111020A: BOOTES-3 Optical Upper Limit.
  26. GRB 111020A: Swift detection of a short burst
  27. GRB 111018A: Swift/UVOT Upper Limits
  28. GRB 111018A: Swift-BAT refined analysis
  29. Konus-Wind observation of GRB 111016B
  30. GRB 111018A: GROND Upper Limits
  31. GRB 111018A: Enhanced Swift-XRT position
  32. IPN Triangulation of GRB 111016B (long duration, intense)
  33. GRB111016A : WIYN 3.5m NIR observations
  34. GRB 111018A: Swift detection of a burst
  35. GRB111016A: D50 optical limit
  36. GRB 111016A: Gemini Detection of the NIR Counterpart
  37. GRB 111016A: Swift/UVOT Detection of a Source
  38. GRB 111016A: Swift-BAT refined analysis
  39. GRB 111016A: P60 Afterglow Candidate
  40. GRB 111016A: Enhanced Swift-XRT position
  41. GRB 111016A: Swift-XRT observations
  42. GRB 111016A: Swift detection of a burst
  43. GRB 110921A: optical observations
  44. GRB 111008A: Swift/UVOT Upper Limits
  45. GRB 111008A: IAC80 I-band observations
  46. GRB 111008A: Gemini spectroscopic redshift
  47. GRB 111008A, GROND observations
  48. GRB 111008A: NOT optical observation
  49. GRB 111008A: Gemini optical counterpart
  50. GRB 111008A: Enhanced Swift-XRT position
  51. GRB 111008A: Swift detection of a burst
  52. GRB 111005A: ATCA 18 GHz detection
  53. GRB 111005A: ATCA radio upper limit
  54. GRB 111005A : miniTAO/ANIR NIR observations
  55. GRB 111005A: EVLA Observations
  56. GRB 111005A: VLT optical observations
  57. GRB 111005A: GROND NIR observations
  58. GRB 111005A: VLT IR observations
  59. GRB 110905A / MAXI J1836-194: optical monitoring
  60. GRB 110921A: MITSuME-Akeno Optical photometry
  61. Skynet/Dolomiti observations of GRB 110928A
  62. Skynet observations of GRB 110928A
  63. GRB 110928A: RAPTOR Limits During Gamma-ray Emitting Interval
  64. GRB 110928A: Swift/UVOT Upper Limits
  65. GRB 110825A: GROND Observations
  66. GRB 110928A: Enhanced Swift-XRT position
  67. GRB 110928A: P60 Observations
  68. GRB 110928A: Further PAIRITEL NIR Observations
  69. GRB 110928A: Swift-XRT observations
  70. GRB 110928A: Swift/UVOT finding chart observation
  71. GRB 110928A: PAIRITEL NIR Observations
  72. GRB 110928A: ROTSE-III Optical Limits
  73. GRB 110924A: Swift detection of a possible burst
  74. GRB 110921A: Swift/UVOT Observations
  75. GRB 110921A: NOT observations
  76. GRB 110921A: TNT astrometry
  77. GRB 110921A: optical observations in Mt. Terskol and Maidanak observatories
  78. GRB 110921A: Enhanced Swift-XRT position
  79. GRB 110921A: MASTER-Net early limit
  80. GRB 110921A: Swift detection of a burst
  81. GRB 110915B : X-ray afterglow confirmation
  82. GRB 110918A: Swift/UVOT Detection of the Optical Counterpart
  83. GRB 110918A optical observation
  84. GRB 110918A: GROND detection of the afterglow candidate
  85. GRB 110918A: INT optical detection of Swift candidate afterglow
  86. GRB 110918A: Swift-XRT observations
  87. Swift detection of short bursts from PSR J1647-4552
  88. GRB 110915A: Konus-Wind and Swift/BAT joint spectral analysis
  89. GRB 110915B: GROND Observations of the Optical/NIR Afterglow Candidate
  90. GRB 110915A: Swift/UVOT Upper Limits
  91. GRB 110915B: Swift/UVOT Upper Limits
  92. GRB 110915A: GROND Upper limits
  93. GRB 110915A, Swift-BAT refined analysis
  94. GRB 110915B: Afterglow candidate from OSN
  95. GRB 110915A: Deep Near-IR Limits from Magellan
  96. GRB 110915B: XRT afterglow candidate
  97. GRB 110903A: Suzaku WAM observation of the prompt emission
  98. GRB 110915A: Deep Gemini-South i/z-band imaging
  99. GRB110915A MITSuME Okayama J-band upper-limit
  100. GRB 110915A: MITSuME Okayama and Ishigakijima Optical upper limits

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