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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"

32888 results found.

  1. Mars Odyssey joins the IPN
  2. IPN triangulation of GRB020413
  3. GRB 020409, 2-nd epoch optical observations at Terskol.
  4. GRB 020409: Optical observations
  5. GRB 020409, No Optical Detection to R = 22
  6. GRB 020409: No Evidence for an Optical Afterglow
  7. GRB 020409, 2nd epoch optical observations
  8. GRB 020331 Kyoto observation on March 31
  9. GRB 020409
  10. GRB 020409 SARA Observations
  11. GRB "020411"
  12. GRB 020409, No Optical Detection to R = 20
  13. GRB020410: BeppoSAX NFI observation
  14. GRB 020409: Optical observations
  15. April 11 BeppoSAX event (GRB020411) is likely not a GRB
  16. GRB 020410, optical observations
  17. BeppoSAX ALERT: possible GRB020411
  18. GRB 020409, optical observations
  19. GRB 020409: Optical Observations
  20. GRB020406(?), optical observations
  21. GRB020410, optical observations
  22. BeppoSAX ALERT: possible GRB020410
  23. X-ray afterglow of GRB020321
  24. BeppoSAX GRB : GRB020409
  25. GRB020405: VLT optical observations and V band decay slope
  26. GRB020331 optical observations with RIMOTS
  27. GRB020124 optical observations with RIBOTS/RIMOTS
  28. GRB 020321: Candidate X-ray Counterparts
  29. ASM GRB candidate 020406 refined error box
  30. GRB 020405: Moderate-resolution spectroscopy
  31. GRB020406(?), optical observations
  32. GRB020405: VLT optical observations
  33. Revised Photometry of the Optical Afterglow of GRB 020405
  34. GRB020405: OT observations
  35. GRB 020331: Candidate Optical Afterglow
  36. GRB 020405: Decay index
  37. Short RXTE/ASM transient 020406; may be a GRB
  38. GRB020405, Radio Observations
  39. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  40. GRB 020405, U-band observations
  41. GRB 020405: Optical afterglow candidate
  42. IPN localization of GRB020405
  43. GRB011212: Optical Observations
  44. GRB 020331: NIR Observations
  45. GRB 020331: NIR Observations
  46. GRB020331 NIR observation at KPNO (re-submission)
  47. GRB02033 NIR observation at KPNO
  48. GRB020331 field photometry
  49. GRB 020331 Optical Observations
  50. GRB 020331, NIR observations
  51. GRB 020331: Optical observations
  52. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  53. GRB 020321: Infrared observations
  54. GRB 020322: BeppoSAX observations of the X-ray afterglow
  55. SN 2002ap - peak brightness date (SN/GRB?)
  56. GRB 020322, Radio observations
  57. Near-Infrared Observations of GRB020322 at TIRGO
  58. GRB 020321, Radio Observations
  59. GRB 020322: Optical Observations
  60. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  61. GRB 020321: Optical observations
  62. GRB020317 BVRI field photometry
  63. GRB011211 revised BVRI field photometry
  64. GRB020305 BVRI field photometry
  65. GRB020322 BVRI field photometry
  66. GRB 020322 optical observations
  67. GRB 020322 optical observation
  68. GRB020317 : Near IR Observations from Mt Abu Observatory
  69. GRB 020322: Optical Sources and Improved Astrometry
  70. GRB020322, optical observations
  71. GRB 020322: Optical candidate
  72. GRB020322: BeppoSAX/NFI Observations
  73. Bepposax GRB020322 The second springtime BSAX GRB
  74. GRB 020321: Optical observations
  75. GRB 011121: Fourth Epoch of HST Imaging
  76. GRB020317: optical observations
  77. GRB020321 optical observations
  78. GRB020321: BeppoSAX/NFI Observations
  79. GRB020321: a faint BeppoSAX detection
  80. GRB 020317 : KISO Optical Observations
  81. BeppoSAX ALERT: GRB020321, the "Springtime Burst"
  82. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  83. GRB 020305: Optical Observations
  84. GRB020317, optical observations
  85. GRB 020317: Optical observations
  86. GRB 011121: Third HST Epoch
  87. GRB020305: Properties of the Candidate Optical Afterglow
  88. GRB 011121: HST Observations reveal an intermediate-time multicolor
  89. GRB011121, possible supernova association
  90. GRB011130 (XRF011130) Second Epoch Chandra Observations
  91. GRB020305: Subaru Optical Observations
  92. GRB 020305: Optical observations
  93. XRF/GRB 011030 Images
  94. XRF/GRB 011030: Detection of the Probable Host Galaxy
  95. GRB 020305: Candidate optical afterglow
  96. Type Ic SN2002bl (SN/GRB?) Radio Observations
  97. GRB020305: Optical Observations
  98. IPN triangulation of GRB020305 (HETE 1939)
  99. GRB020305 (=H1939): Localization of a GRB by HETE
  100. GRB 020305: Optical observations

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