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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"

17384 results found.

  1. AXP 1E2259+586 optical observations
  2. Fading Optical Source in the Field of GRB020531
  3. GRB 020531, INT+WFC deep optical upper limits
  4. SGR-like Bursts from the AXP 1E 2259+586
  5. GRB020405: polarimetric observations
  6. GRB 020531, simultaneous optical observations
  7. GRB 020604, optical observations
  8. GRB020531: Second epoch Chandra observations
  9. GRB020604, optical observations
  10. GRB020604, BVRcIc field photometry
  11. GRB020603, BVRcIc field observations
  12. GRB020531, BVRcIc field photometry
  13. IPN triangulation of GRB020604
  14. GRB020531 Optical Observations
  15. GRB020531: Observations with the Chandra X-ray Observatory
  16. GRB020531, optical observations
  17. GRB020531: optical observations
  18. GRB020531(=H2042): Optical Observations
  19. GRB020531(=H2042): Optical Observations
  20. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  21. GRB020525, optical observations
  22. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  23. GRB020405 field photometry at ESO
  24. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  25. XRF 020427
  26. GRB 020410, Radio Observations
  27. GRB 020124: Optical observations
  28. GRB020405: VLT observations of the OT environment
  29. IPN triangulation of GRB020413
  30. GRB020405: predicted break
  31. GRB 020409: No Evidence for an Optical Afterglow
  32. GRB 020331 Kyoto observation on March 31
  33. X-ray afterglow of GRB020321
  34. GRB020331 optical observations with RIMOTS
  35. GRB020124 optical observations with RIBOTS/RIMOTS
  36. GRB020406(?), optical observations
  37. GRB020405, Radio Observations
  38. GRB 020405, U-band observations
  39. GRB020331 NIR observation at KPNO (re-submission)
  40. GRB02033 NIR observation at KPNO
  41. GRB020331 field photometry
  42. GRB 020331, NIR observations
  43. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  44. GRB 020322: BeppoSAX observations of the X-ray afterglow
  45. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  46. Near-Infrared Observations of GRB020322 at TIRGO
  47. GRB 020322: Optical Observations
  48. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  49. GRB 020321: Optical observations
  50. GRB020317 BVRI field photometry
  51. GRB011211 revised BVRI field photometry
  52. GRB020305 BVRI field photometry
  53. GRB020322 BVRI field photometry
  54. GRB 020322: Optical Sources and Improved Astrometry
  55. GRB020317: optical observations
  56. GRB020321 optical observations
  57. GRB020321: a faint BeppoSAX detection
  58. GRB 020317 : KISO Optical Observations
  59. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  60. GRB 020305: Optical Observations
  61. GRB020317, optical observations
  62. GRB 020317: Optical observations
  63. GRB 011121: Third HST Epoch
  64. GRB020305: Properties of the Candidate Optical Afterglow
  65. GRB011130 (XRF011130) Second Epoch Chandra Observations
  66. XRF/GRB 011030: Detection of the Probable Host Galaxy
  67. GRB020305, optical observations
  68. GRB020305 (=H1939): Localization of a GRB by HETE
  69. HST Imaging of the afterglow and host of GRB 011121
  70. IPN detection and localization of Cygnus X-1 flares
  71. SGR1900+14 activity
  72. GRB020124 BVRI field photometry
  73. SN2002ap (SN/GRB?) optical spectrographic observations
  74. GRB020127 Optical Observations
  75. SN2002ap (SN/GRB?) UBVRI Field Photometry
  76. GRB020127: Chandra Observations and Prospective Counterparts
  77. pre-SN2002ap (SN/GRB?) imaging of M74
  78. GRB020124, optical observations
  79. GRB020127: Optical observations
  80. GRB 020127, I-band observations starting 3.14-hr after the event
  81. GRB010921 Optical Observations
  82. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  83. GRB020124: Optical observations
  84. GRB 020124: Optical observations
  85. GRB020124(=H1896): Localization of a Long GRB by HETE
  86. Possible optical counterpart to a GRB
  87. GRB011212, Optical Observations
  88. GRB011211: BeppoSAX/GRBM data
  89. Optical polarization observations for GRB011211
  90. GRB 011130: Optical Observations of X-ray and Radio Sources
  91. GRB 011212: optical observation at Asiago
  92. GRB 011211: Evidence for an Optical Break
  93. GRB 011212: optical observation at Oslo (relayed)
  94. GRB 011211: Optical Spectroscopy
  95. GRB 011211, Optical Observations
  96. GRB011212, BVRI field photometry
  97. GRB011211, BVRI field photometry
  98. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  99. Fading of the optical source associated of XRF 011211
  100. GRB011130 (=XRF011130): Further analysis of Chandra Target of

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