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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"

3821 results found.

  1. Radio Detection of SGR 0501+4516
  2. SGR 0501+4516: MDM Optical Observations
  3. SGR 0501+4516: Astrotel-Caucasus optical observations
  4. SGR 0501+4516: UKIRT detection of possible infra-red counterpart
  5. SGR 0501+4516: WSRT Radio Observations
  6. Trigger 321551: Continued Large Flaring of SGR 0501+4516
  7. SGR 0501+4516: optical observations
  8. Swift Trigger 321481: A Large Flare from SGR 0501+4516
  9. SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
  10. Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
  11. Third event from SGR 0501+4516
  12. GRB 080822 (SGR 0501+4516): archival optical observations
  13. New Soft Gamma Repeater 0501+4516 was GRB 080822
  14. GRB 080727B: Late VLT imaging
  15. Trigger 317393: Swift detection of a possible GRB
  16. Trigger 317205: Swift detection of an outburst from XTE J1701-407
  17. GRB 080710, Swift-BAT refined analysis
  18. GRB 080710: Swift detection of a burst
  19. GRB 080707: Swift detection of a burst
  20. GRB 080702B : Burst detected in BAT during Swift slew
  21. GRB 080701: Swift detection of a burst
  22. GRB 080613B: Swift detection of a burst
  23. GRB 080604: Swift detection of a burst with an optical afterglow
  24. SGR 1627-41: Chandra/RXTE/Swift Observations Scheduled
  25. Konus-Wind observation of reactivation of SGR 1627-41
  26. Reactivation of SGR 1627-41
  27. GRB 080515: KPNO 4m NIR afterglow detection
  28. GRB 080506: NAYUTA Optical Observation
  29. GRB080430: Optical observation in AsU CAS Ondrejov & Brno
  30. GRB 080426: Swift detection of a possibly short burst
  31. GRB 080413A: MOA-II optical afterglow observations
  32. GRB 080330, SMARTS optical/IR afterglow observations
  33. GRB 080319A: UVOT Observations
  34. GRB 080319C: Swift-XRT Team Refined Analysis
  35. GRB 080319C: Swift detection of a burst with an optical afterglow
  36. GRB080310: Super-LOTIS suggestion of brightening
  37. GRB080307, optical upper limit
  38. GRB 080307: retraction of UVOT candidate
  39. GRB 080303A: ROTSE-III Optical Limits
  40. GRB080229: Possible optical afterglow
  41. UVOT analysis for GRB080229
  42. GRB 080218: Swift detection of a burst
  43. GRB 080207, Swift-BAT refined analysis
  44. GRB 080207, Swift-BAT refined analysis
  45. GRB 080129: Swift-XRT refined analysis
  46. GRB 080129: Gemini-South Imaging Observations
  47. Konus-Wind observation of GRB 080122
  48. GRB 080121: Swift-BAT detection of a very weak, short burst
  49. IPN triangulation of very bright GRB 071125
  50. Disregard the "GRB 071126" position
  51. GRB 071118: Swift detection of a burst
  52. GRB 071101: Swift detection of a burst
  53. GRB 071028: Swift-XRT Team refined analysis
  54. GRB 071028: Swift detection of a burst
  55. GRB071020, optical upper limit
  56. GRB 071017: a SHORT GRB detected by INTEGRAL
  57. GRB071010B: Swift/XRT detection
  58. GRB 070911, SMARTS optical/IR afterglow observations
  59. GRB 070920B: ROTSE-III Early Optical Limits
  60. INTEGRAL ToO observations of SGR1806-20
  61. GRB 070920b, SMARTS optical observation
  62. SGR1806-20: Swift-BAT detection of enhanced activity
  63. GRB 070911: Swift XRT refined analysis
  64. GRB 070911, Swift-BAT refined analysis
  65. Intense burst from SGR 1806-20 detected on September 7
  66. GRB 070810: ROTSE-III Detection of Optical Counterpart
  67. GRB 070809: ROTSE-III Optical Limits
  68. GRB 070808: Xinglong TNT optical Upper Limit
  69. GRB070808: Optical observations with KANATA
  70. GRB 070808: Swift detection of a burst
  71. Swift detection of a outburst from SAX J1810.8-2609
  72. VLA non-detection of GRB 070721B
  73. AGILE-ACS position for the SGR 1806-20 July 27 burst
  74. Intense burst from SGR 1806-20 detected on July 27
  75. GRB 070326: Detection of first burst from BAT Slew Survey (BATSS)
  76. GRB 070714: Swift detection of a bright burst, possibly short
  77. GRB 070628: Watcher Observations
  78. OT20050728 was not an optical GRB afterglow
  79. GRB 070616: Swift detection of a burst
  80. GRB 070612A: P60 Confirmation of Afterglow and An Underlying, Nearby
  81. GRB 070611: Swift/UVOT Observations
  82. GRB 070611: ROTSE-III Detection of Late Rising Optical Counterpart
  83. GRB 070611; Swift-XRT position
  84. Swift trigger 280447 is probably a Galactic transient
  85. GRB 070518: MARGE Observations
  86. GRB070521: P200 Observations
  87. GRB 070508: Suzaku/WAM observation of the prompt emission
  88. GRB 070507: Swift detection of a possible cosmic ray shower event or a possible burst
  89. GRB070429B: VLT observations
  90. GRB070429B: possible host galaxy detection
  91. Konus-Wind observation of GRB 070420
  92. GRB 070420 Swift-BAT Refined Analysis
  93. Suzaku ToO observation of SGR 1806-20
  94. INTEGRAL ToO Observation of SGR1806-20
  95. long burst from SGR 1806-20 detected on March 26
  96. Short-Hard GRB 070209: PROMPT Observations
  97. GRB 070318: Swift detection of a burst with an optical afterglow
  98. GRB 070224: SARA upper limit
  99. GRB 070224: MASTER-Net refind analysis
  100. GRB 070224: MASTER-VWF-Kislovodsk observations

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