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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"

12318 results found.

  1. GRB 130502A: Swift/UVOT Upper Limits
  2. GRB 130502B: P60 Observations
  3. GRB 130502A: RATIR Optical and NIR Observations
  4. GRB 130427A: MITSuME Ishigakijima Optical Observation after 5 days
  5. GRB 130502A: Swift detection of a burst
  6. GRB 130425: MASTER-Net optical observations
  7. GRB 130427B: MITSuME Ishigakijima upper limits
  8. GRB 130427B: RATIR Optical and NIR Observations
  9. GRB 130427B: MITSuME Okayama upper limits
  10. GRB 130427A: MAXI/GSC detection
  11. Trigger 554491: Swift detection of a spike possibly from Sgr A*
  12. GRB 130420A: Continued RATIR Optical and NIR Observations
  13. GRB 130420A: Continued RATIR Optical and NIR Observations
  14. GRB 130418A: Continued RATIR Optical and NIR Observations
  15. Swift Trigger 554135 is probably not a GRB or transient
  16. GRB 130420B: RATIR Optical and NIR Observations
  17. GRB 130420B: Weihai optical upper limit
  18. GRB 130420B: Swift/UVOT Upper Limits
  19. GRB 130420A: Swift/UVOT Detection
  20. GRB130420B: GMG optical upper limit
  21. GRB130420A : Xinglong TNT optical upper limit
  22. GRB 130420B: MASTER-Net optical observations
  23. GRB 130420B: Swift detection of a burst
  24. GRB 130419B (Swift trigger Trigger 553930): MASTER-Net optical observations
  25. GRB 130407A: Swift-XRT observations
  26. GRB130408A: Swift/UVOT followup observations
  27. GRB 130407A: MAXI/GSC detection
  28. Swift detection of IGR J18245-2452
  29. GRB 130306A: Confirmation of the X-ray Afterglow
  30. Swift Trigger 552142: a possible GRB
  31. GRB 130327A: Gemini Observations
  32. GRB 130327A: Swift/UVOT Upper Limits
  33. GRB 130327A: ISON-NM optical upper limit
  34. GRB 130327A: RATIR Optical and NIR Observations
  35. GRB 130305A: optical upper limit in Mondy observatory
  36. GRB 130315A: Swift/UVOT Upper Limits
  37. GRB 130313A: optical upper limit in CrAO
  38. GRB 130313A: optical upper limit in Mondy observatory
  39. GRB 130315A: SALT optical observations
  40. GRB 130313A: 5.8 GHz VLA upper limit
  41. Swift XRT observations of GRB 130310A
  42. GRB 130313A: Swift/UVOT Upper Limits
  43. GRB 130305A: PTF P48 optical upper limits
  44. GRB 130315A: Swift detection of a burst
  45. GRB 130305A: TLS Tautenburg observations
  46. GRB 130313A: RATIR Optical and NIR Observations
  47. GRB 130313A: Fading X-ray Afterglow
  48. GRB 130313A: NOT optical upper limit
  49. GRB 130313A: Weihai optical upper limit
  50. GRB 130313A: MASTER-Net optical observations
  51. GRB 130313A: Swift detection of a short burst
  52. GRB 130306A: Swift Detection of a Possible Afterglow
  53. GRB 130306A: MITSuME Ishigakijima upper limits
  54. GRB 130305A: Gemini-North upper limit
  55. GRB 130306A: MASTER-Net pre-Swift alert observation
  56. GRB 130305A: Swift/UVOT Upper Limit
  57. GRB 130305A: RATIR Observations
  58. GRB 121128A: optical upper limit in Maidanak observatory
  59. GRB 130216A: Swift/UVOT Upper Limit
  60. SGR 1806-20 outburst (trigger 549841), Swift-BAT refined analysis
  61. GRB 130216A: possible radio counterpart is steady field source
  62. GRB 130216A: Swift/XRT observations
  63. GRB 130216B: Swift/XRT observations
  64. GRB 130216B: MASTER-Net early observation
  65. GRB 130216A: MASTER-Net early observations
  66. GRB 130216A: MITSuME Ishigakijima upper limits
  67. GRB 130215A: MITSuME Okayama Optical Observation
  68. Swift GRB130206A: late XRT observations.
  69. GRB 130131B: CTIO 0.9-m optical upper-limits
  70. GRB 130211A: Swift/UVOT Upper Limits
  71. GRB 130211A: Swift detection of a burst
  72. GRB 130131A: MITSuME Akeno Optical upper limits
  73. GRB 130131B: MITSuME Akeno Optical upper limits
  74. GRB 130122A: PTF P48 optical upper limits
  75. GRB 130206A: GROND Observations
  76. GRB 130206A: Fermi LAT Observations
  77. GRB 130206A: XRT and UVOT follow-up observations.
  78. GRB 130131B: optical upper limit in Mondy observatory
  79. GRB 130131A: Swift/UVOT Upper Limits
  80. GRB 130131B: RATIR Upper Limits
  81. GRB 130131A: RATIR optical and infrared upper limits
  82. GRB 130131B: GROND Upper limits
  83. GRB 130131B: Swift/UVOT Upper Limits
  84. GRB 130131B: MITSuME Okayama optical upper limits
  85. GRB 130131A: MITSuME Okayama optical upper limits
  86. GRB 130131B: Swift detection of a burst
  87. GRB 130131A: Swift detection of a burst
  88. Swift Trigger 547142: MAXI/GSC upper limit
  89. GRB 130122A: Swift/UVOT Detection
  90. GRB 130122A: RATIR Detection
  91. GRB 130122A: Xinglong optical upper limit
  92. GRB 130102B: MASTER synchronous observations
  93. GRB 130102A: Swift/UVOT Upper Limits
  94. GRB 130102A: MASTER-Net optical observations
  95. GRB 130102B: MAXI/GSC detection
  96. GRB 130102A: Swift detection of a burst
  97. GRB 121229A: Swift/UVOT Upper Limits
  98. GRB 121229A: MAXI/GSC detection
  99. GRB 121229A: Swift detection of a burst
  100. GRB 121226A: Swift/UVOT Upper Limits

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