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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"

28077 results found.

  1. GRB070621: RTT150 optical observations
  2. GRB 070621: VLT optical observations
  3. GRB 070621: Swift/UVOT Upper Limits
  4. Keck Laser Guide Star Adaptive Optics Imaging of GRB 070621
  5. WHT observations of GRB070621
  6. GRB070621: Swift XRT refined analysis
  7. GRB 070621: Gemini South optical imaging
  8. GRB 070621: UVOT-enhanced XRT position
  9. Observations of GRB070612A at Calar Alto
  10. GRB 070621: NOT observations
  11. GRB070621: OPTIMA-Burst optical upper limit
  12. GRB 070621: TAROT Calern observatory optical observations
  13. GRB 070621: Watcher Observations
  14. GRB 070621: ROTSE-III Prompt Optical Limits
  15. GRB 070621: Swift detection of a burst
  16. GMRT upper limit of GRB 070610/SWIFT J195509.6+261406 in 610 MHz
  17. GRB 070612A: TNG optical observations
  18. Swift/UVOT detection of GRB070616 optical afterglow.
  19. GRB070612A: Gemini Spectroscopic Redshift
  20. GRB 070612A: NOT observations
  21. GRB070616: Optical Observation by MITSuME Akeno
  22. GRB 070612B: Optical Observation by MITSuME Akeno
  23. GRB070616: Optical Observation by MITSuME Okayama
  24. GRB 070616, Swift-BAT further refined analysis
  25. GRB 070616: Swift XRT refined circular
  26. GRB 070612A: Possible WSRT Radio Detection
  27. GRB 070616: BTA astrometry and finding chart
  28. GRB 070616: BTA optical observations
  29. Swift/UVOT observations of GRB070616
  30. GRB 070616: TLS observation
  31. Swift XRT observations of the INTEGRAL burst GRB070615: Possible
  32. GRB 070616: Swift detection of a burst
  33. GRB 070612B: optical observations
  34. UVOT Observations of INTEGRAL burst GRB070615
  35. VLA upper limit on GRB 070610
  36. GRB 070612A: Super-LOTIS observations
  37. GRB 070612A: Rapid Decay
  38. GRB070612A: MITSuME Okayama Observation
  39. GRB 070612A: continued SARA observations
  40. GRB 070611: Watcher Observations
  41. GRB 070612A: MDM Observations
  42. GRB 070612A: P60 Confirmation of Afterglow and An Underlying, Nearby
  43. GRB 070612B: SARA upper limit
  44. GRB 070612B: Swift-XRT refined analysis
  45. SWIFT J195509.6+261406 / GRB 070610: SWIFT continued observations
  46. GRB 070612B: Swift/UVOT upper limits
  47. GRB 070612B: FRAM limit
  48. GRB070612B: P60 Observations
  49. GRB 070612B: KAIT limits
  50. GRB 070612A: SARA detection of possible OT
  51. GRB 070612B: Swift XRT position from downlink data
  52. GRB 070610: TAROT Calern observatory optical observations
  53. GRB 070610: MITSuME OAO optical upper limit
  54. GRB 070612B: Swift detection of a burst
  55. GRB 070612: Swift detection of a burst
  56. GRB 070610: OPTIMA-Burst detection of continued strong flaring activity
  57. GRB 070610: Swift-XRT refined analysis
  58. GRB 070610: TLS RRM sees flaring behaviour - Galactic transient?
  59. GRB 070611: Swift/UVOT Observations
  60. GRB 070611: Swift-XRT refined analysis
  61. GRB 070610: Optical observations from OSN
  62. GRB 070610: Watcher Observations
  63. GRB 070611: ROTSE-III Detection of Late Rising Optical Counterpart
  64. GRB 070611; Swift-XRT position
  65. GRB 070611: Swift detection of a burst
  66. GRB 070610: Swift-UVOT Upper Limits
  67. GRB 070610: OPTIMA-Burst high-time-resolution optical observations
  68. GRB 070610; Swift-XRT position
  69. GRB 070610: Swift detection of a burst
  70. GRB 070412: TAROT Calern observatory optical observations
  71. GRB 070419A, deep LBT photometry and possible supernova detection
  72. GRB070520B: optical observations
  73. GRB070520: optical observation
  74. GRB070521: optical observation
  75. Swift/UVOT refined analysis of GRB070531
  76. GRB 070531: NOT nIR observations
  77. GRB 070531: I-band observations from IAC80
  78. GRB 070531: Swift-XRT position
  79. GRB 070531: Swift detection of a burst
  80. GRB 070529: SARA upper limit
  81. Swift/UVOT refined analysis of GRB070529
  82. GRB 070529: Gemini Redshift
  83. GRB 070529: Swift-XRT refined analysis
  84. GRB 070529: Swift detection of a burst with an optical aterglow
  85. GRB 070412: Deep Keck imaging
  86. Swift trigger 280447 is probably a Galactic transient
  87. GRB 070518, deep LBT photometry
  88. GRB070521: Second Epoch Gemini Imaging
  89. GRB070521: NIR observations
  90. GRB070520B: NIR observations
  91. GRB 070521: Swift/UVOT Upper Limits
  92. GRB 070521: Swift-XRT refined analysis
  93. GRB 070521: Keck imaging
  94. GROND upper limits of GRB 070521
  95. GRB 070521: SARA upper limit
  96. GRB 070521: Subaru observations and possible host detection
  97. GRB070518: Optical/NIR observation
  98. GRB 070520B: Swift/UVOT Upper Limits
  99. GRB 070520A: Subaru Observations
  100. GRB 070520A: Swift UVOT Upper Limits

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