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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"

24363 results found.

  1. GRB 020625, optical observations
  2. GRB020625 (=H2081): A Long Burst Localized by HETE
  3. GRB/XRF 020427, detection of an underlying system with the VLT
  4. Fading Optical Source in the Field of GRB020531
  5. GRB 020531, INT+WFC deep optical upper limits
  6. GRB 020604, optical observations
  7. GRB020604, BVRcIc field photometry
  8. GRB020531 Optical observations with TAROT
  9. GRB 020418, optical/near-IR observations
  10. GRB 020603, R-band observation
  11. Correction to IPN triangulation of GRB020603 (possible short/hard burst)
  12. GRB 020531 optical observations with TAROT
  13. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  14. IPN detection of possible bursts from SGR1806-20
  15. HST detection of the likely host galaxy of GRB 020124
  16. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  17. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  18. XRF 020427
  19. The end of BSAX GRB activities
  20. GRB 020124: Optical observations
  21. Mars Odyssey joins the IPN
  22. GRB020405: predicted break
  23. GRB 020409: No Evidence for an Optical Afterglow
  24. GRB 020409, 2nd epoch optical observations
  25. GRB 020331 Kyoto observation on March 31
  26. GRB 020409, No Optical Detection to R = 20
  27. BeppoSAX ALERT: possible GRB020411
  28. GRB 020409, optical observations
  29. BeppoSAX ALERT: possible GRB020410
  30. GRB020331 optical observations with RIMOTS
  31. GRB020124 optical observations with RIBOTS/RIMOTS
  32. GRB 020321: Candidate X-ray Counterparts
  33. ASM GRB candidate 020406 refined error box
  34. GRB 020331: Candidate Optical Afterglow
  35. Short RXTE/ASM transient 020406; may be a GRB
  36. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  37. IPN localization of GRB020405
  38. GRB 020331: NIR Observations
  39. GRB020331 NIR observation at KPNO (re-submission)
  40. GRB02033 NIR observation at KPNO
  41. GRB 020331, NIR observations
  42. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  43. GRB 020322: BeppoSAX observations of the X-ray afterglow
  44. SN 2002ap - peak brightness date (SN/GRB?)
  45. GRB 020322 optical observations
  46. GRB 011121: Fourth Epoch of HST Imaging
  47. GRB020321: a faint BeppoSAX detection
  48. GRB 020317 : KISO Optical Observations
  49. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  50. GRB 020305: Optical Observations
  51. GRB020317, optical observations
  52. GRB 011121: Third HST Epoch
  53. GRB 011121: HST Observations reveal an intermediate-time multicolor
  54. GRB011121, possible supernova association
  55. XRF/GRB 011030: Detection of the Probable Host Galaxy
  56. GRB020305, optical observations
  57. IPN triangulation of GRB020305 (HETE 1939)
  58. GRB020305 (=H1939): Localization of a GRB by HETE
  59. HST Imaging of the afterglow and host of GRB 011121
  60. IPN detection and localization of Cygnus X-1 flares
  61. RXTE Observations of SGR 1900+14
  62. IPN detection of further SGR1900+14 activity
  63. SGR1900+14 activity
  64. IPN/HETE Detection of Bursts from SGR1900+14
  65. IPN Upper Limits to a GRB Associated With SN2002ap
  66. GRB020127: Palomar and VLA Observations of Possible Counterparts
  67. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  68. SN2002ap (SN/GRB?) Echelle spectra
  69. GRB020127 Optical Observations
  70. SN2002ap (SN/GRB?) UBVRI Field Photometry
  71. GRB020127: Chandra Observations and Prospective Counterparts
  72. GRB020124, optical observations
  73. IPN detection of further activity from SGR1806-20
  74. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  75. GRB020124: Optical observations
  76. IPN observations of SGR1806-20
  77. GRB 020124: Optical afterglow
  78. GRB020124(=H1896): Localization of a Long GRB by HETE
  79. GRB 011211, spectrum and optical photometry
  80. GRB 011211: TNG Spectroscopic Observations
  81. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  82. GRB011130, optical observations
  83. GRB011130 (=XRF011130): Second Revised Localization by HETE
  84. GRB011130 (XRF011130) optical observations
  85. GRB011130 (=XRF011130): Revised Localization of an X-ray
  86. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  87. GRB 011121: J-band observations
  88. GRB011121
  89. GRB011030: Z-band observations
  90. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  91. GRB 970828: HST Observations of the Host Galaxy
  92. GRB 000131: HST Detection of the Host Galaxy
  93. GRB 970828: HST Observations of the Host Galaxy
  94. GRB010921, optical observation
  95. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  96. GRB011019: Subaru Optical Observations
  97. GRB010921, optical observation at early time
  98. GRB 010921, I-band observations
  99. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  100. GRB010921: Spectroscopy of the Host Galaxy

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