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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"

7404 results found.

  1. GRB 071021: Faulkes Telescope South optical candidate
  2. GRB 071018: SARA observations
  3. GRB 071013: 3rd TLS Epoch - constraints on variability
  4. GRB 071013: TLS 2nd epoch - Kornienko candidate constant
  5. GRB 071013: Optical observations
  6. GRB 071013: optical observations at NOT
  7. GRB071013: optical limit
  8. GRB 071011, Optical afterglow
  9. GRB 071011: Confirmation of P60 optical afterglow
  10. GRB 071011: P60 Optical Afterglow Candidate
  11. GRB 071011: MARGE Optical Limits
  12. GRB 071011: XRT afterglow detection
  13. GRB 071011: Early Super-LOTIS Observations
  14. GRB 071011: Optical afterglow candidate
  15. Optical Observation: GRB 071010
  16. Optical observations: GRB 071010A
  17. GRB 071010 REM NIR observations
  18. GRB 071003 Optical observations
  19. GRB 071003: P60 Confirmation of Optical Afterglow
  20. GRB 070925: Gemini South Imaging
  21. GRB 070920B: NOT optical observations
  22. GRB070917: Confirmation of optical afterglow
  23. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  24. GRB 070913: Afterglow candidate detected by TAROT La Silla observatory
  25. IPN search for a GRB associated with TAROT transient on August 31
  26. Observations of possible TAROT GRB transient near IC 4779
  27. Candidate Orphan GRB Optical Transient in IC 4779
  28. GRB 070810b: Image Subtraction of Multiple Keck Observations
  29. Orphan GRB candidate in IC 4779 at TAROT La Silla observatory
  30. GRB 070731: Swift/UVOT Upper Limit
  31. GRB 070805: UVOT afterglow candidate retraction
  32. GRB070810b: optical candidate
  33. GRB 070810: MASTER optical observation
  34. Swift Alert 070810.8: MASTER optical observation
  35. GRB 070810B: Swift detection of a short burst
  36. GRB 070810: Swift detection of a burst
  37. GRB 070808: Swift detection of a burst
  38. GRB070805 XRT and UVOT afterglow candidate
  39. GRB 070805: Swift/UVOT initial analysis
  40. Swift detection of a outburst from SAX J1810.8-2609
  41. GRB 070802: REM optical observations
  42. GRB 070724B: Swift-XRT afterglow confirmation
  43. GRB 070802: VLT redshift
  44. GRB 070802: V-band detection of the candidate afterglow
  45. GRB 070802: LCO I-band candidate
  46. GRB 070802: GROND J band candidate
  47. GRB 070802: Swift detection of a burst
  48. GRB 070729: Swift detection of a short hard burst
  49. GRB 070724B: Swift/UVOT Upper limits
  50. GRB 070724B: Swift-XRT afterglow likely candidate
  51. GRB 070724: Pre-Imaging Shows a Source in the XRT Error Circle
  52. GRB 070724: Swift detection of a burst
  53. GRB 070721B : Faulkes Telescope South observations
  54. GRB070721B: A bright UVOT candidate
  55. GRB 070714B: confirmation of optical afterglow
  56. GRB070714B: Swift-XRT refined analysis
  57. SN 2007bg - off-axis GRB?
  58. GRB 070707: VLT observations
  59. GRB 070429B: NIR Observations
  60. GRB 070704: Swift detection of a burst
  61. Swift UVOT Observations of GRB 070628
  62. GRB 070621: Swift detection of a burst
  63. GRB070616: Optical Observation by MITSuME Akeno
  64. GRB070616: Optical Observation by MITSuME Okayama
  65. GRB 070616: BTA astrometry and finding chart
  66. GRB 070616: Swift detection of a burst
  67. GRB070612A: MITSuME Okayama Observation
  68. GRB 070612A: MDM Observations
  69. GRB 070612A: P60 Confirmation of Afterglow and An Underlying, Nearby
  70. GRB 070610: MITSuME OAO optical upper limit
  71. GRB 070610: Swift-XRT refined analysis
  72. GRB 070611: Swift/UVOT Observations
  73. GRB 070611: Swift-XRT refined analysis
  74. GRB 070611: ROTSE-III Detection of Late Rising Optical Counterpart
  75. GRB 070610: Swift-UVOT Upper Limits
  76. GRB 070411: TAROT Calern observatory optical observations
  77. GRB070520B: optical observations
  78. GRB070520: optical observation
  79. GRB070518: optical observation
  80. GRB070521: optical observation
  81. GRB 070531: Swift detection of a burst
  82. GRB 070529: Swift detection of a burst with an optical aterglow
  83. GRB070521: Second Epoch Gemini Imaging
  84. GRB 070521: Keck imaging
  85. GRB070521: Gemini Observations
  86. GRB 070521: Subaru observations and possible host detection
  87. GRB 070520A: Subaru Observations
  88. GRB 070521: Swift detection of a burst
  89. GRB 070520B: Swift detection of a burst
  90. GRB 070520: Swift detection of a burst
  91. GRB 070510: Swift detection of a possible burst
  92. GRB 070508: OA fading and tentative redshift
  93. GRB 070509: Swift detection of a burst
  94. GRB 070508: TAROT La Silla observatory optical observations
  95. GRB 070508: Swift detection of an intense burst with an optical counterpart
  96. GRB 070507: Swift detection of a possible cosmic ray shower event or a possible burst
  97. GRB 070506: Swift detection of a burst with optical afterglow
  98. GRB 070309: Swift-XRT afterglow confirmation
  99. GRB 070429B: Swift detection of a short burst
  100. GRB 070429: Swift detection of a burst

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