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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"

7400 results found.

  1. GRB 071013: Optical observations
  2. GRB 071013: optical observations at NOT
  3. GRB071013: optical limit
  4. GRB 071011, Optical afterglow
  5. GRB 071011: Confirmation of P60 optical afterglow
  6. GRB 071011: P60 Optical Afterglow Candidate
  7. GRB 071011: MARGE Optical Limits
  8. GRB 071011: XRT afterglow detection
  9. GRB 071011: Early Super-LOTIS Observations
  10. GRB 071011: Optical afterglow candidate
  11. Optical Observation: GRB 071010
  12. Optical observations: GRB 071010A
  13. GRB 071010 REM NIR observations
  14. GRB 071003 Optical observations
  15. GRB 071003: P60 Confirmation of Optical Afterglow
  16. GRB 070925: Gemini South Imaging
  17. GRB 070920B: NOT optical observations
  18. GRB070917: Confirmation of optical afterglow
  19. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  20. GRB 070913: Afterglow candidate detected by TAROT La Silla observatory
  21. IPN search for a GRB associated with TAROT transient on August 31
  22. Observations of possible TAROT GRB transient near IC 4779
  23. Candidate Orphan GRB Optical Transient in IC 4779
  24. GRB 070810b: Image Subtraction of Multiple Keck Observations
  25. Orphan GRB candidate in IC 4779 at TAROT La Silla observatory
  26. GRB 070731: Swift/UVOT Upper Limit
  27. GRB 070805: UVOT afterglow candidate retraction
  28. GRB070810b: optical candidate
  29. GRB 070810: MASTER optical observation
  30. Swift Alert 070810.8: MASTER optical observation
  31. GRB 070810B: Swift detection of a short burst
  32. GRB 070810: Swift detection of a burst
  33. GRB 070808: Swift detection of a burst
  34. GRB070805 XRT and UVOT afterglow candidate
  35. GRB 070805: Swift/UVOT initial analysis
  36. Swift detection of a outburst from SAX J1810.8-2609
  37. GRB 070802: REM optical observations
  38. GRB 070724B: Swift-XRT afterglow confirmation
  39. GRB 070802: VLT redshift
  40. GRB 070802: V-band detection of the candidate afterglow
  41. GRB 070802: LCO I-band candidate
  42. GRB 070802: GROND J band candidate
  43. GRB 070802: Swift detection of a burst
  44. GRB 070729: Swift detection of a short hard burst
  45. GRB 070724B: Swift/UVOT Upper limits
  46. GRB 070724B: Swift-XRT afterglow likely candidate
  47. GRB 070724: Pre-Imaging Shows a Source in the XRT Error Circle
  48. GRB 070724: Swift detection of a burst
  49. GRB 070721B : Faulkes Telescope South observations
  50. GRB070721B: A bright UVOT candidate
  51. GRB 070714B: confirmation of optical afterglow
  52. GRB070714B: Swift-XRT refined analysis
  53. SN 2007bg - off-axis GRB?
  54. GRB 070707: VLT observations
  55. GRB 070429B: NIR Observations
  56. GRB 070704: Swift detection of a burst
  57. Swift UVOT Observations of GRB 070628
  58. GRB 070621: Swift detection of a burst
  59. GRB070616: Optical Observation by MITSuME Akeno
  60. GRB070616: Optical Observation by MITSuME Okayama
  61. GRB 070616: BTA astrometry and finding chart
  62. GRB 070616: Swift detection of a burst
  63. GRB070612A: MITSuME Okayama Observation
  64. GRB 070612A: MDM Observations
  65. GRB 070612A: P60 Confirmation of Afterglow and An Underlying, Nearby
  66. GRB 070610: MITSuME OAO optical upper limit
  67. GRB 070610: Swift-XRT refined analysis
  68. GRB 070611: Swift/UVOT Observations
  69. GRB 070611: Swift-XRT refined analysis
  70. GRB 070611: ROTSE-III Detection of Late Rising Optical Counterpart
  71. GRB 070610: Swift-UVOT Upper Limits
  72. GRB 070411: TAROT Calern observatory optical observations
  73. GRB070520B: optical observations
  74. GRB070520: optical observation
  75. GRB070518: optical observation
  76. GRB070521: optical observation
  77. GRB 070531: Swift detection of a burst
  78. GRB 070529: Swift detection of a burst with an optical aterglow
  79. GRB070521: Second Epoch Gemini Imaging
  80. GRB 070521: Keck imaging
  81. GRB070521: Gemini Observations
  82. GRB 070521: Subaru observations and possible host detection
  83. GRB 070520A: Subaru Observations
  84. GRB 070521: Swift detection of a burst
  85. GRB 070520B: Swift detection of a burst
  86. GRB 070520: Swift detection of a burst
  87. GRB 070510: Swift detection of a possible burst
  88. GRB 070508: OA fading and tentative redshift
  89. GRB 070509: Swift detection of a burst
  90. GRB 070508: TAROT La Silla observatory optical observations
  91. GRB 070508: Swift detection of an intense burst with an optical counterpart
  92. GRB 070507: Swift detection of a possible cosmic ray shower event or a possible burst
  93. GRB 070506: Swift detection of a burst with optical afterglow
  94. GRB 070309: Swift-XRT afterglow confirmation
  95. GRB 070429B: Swift detection of a short burst
  96. GRB 070429: Swift detection of a burst
  97. GRB 070420: Swift detection of a burst with optical afterglow
  98. GRB 070419A Swift-BAT Refined Analysis
  99. GRB 070419B: Swift XRT refined analysis
  100. GRB 070419A, Optical observations

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