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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"

24368 results found.

  1. GRB020331: Late-time Optical Light Curve (re-submission)
  2. GRB020331: Late-time Optical Light Curve
  3. GRB 020405: HST observations reveal red bump
  4. IPN triangulation of GRB020714
  5. GRB 020410: Discovery of Probable OT by HST
  6. GRB 020625, optical observations
  7. GRB020625 (=H2081): A Long Burst Localized by HETE
  8. GRB/XRF 020427, detection of an underlying system with the VLT
  9. Fading Optical Source in the Field of GRB020531
  10. GRB 020531, INT+WFC deep optical upper limits
  11. GRB 020604, optical observations
  12. GRB020604, BVRcIc field photometry
  13. GRB020531 Optical observations with TAROT
  14. GRB 020418, optical/near-IR observations
  15. GRB 020603, R-band observation
  16. Correction to IPN triangulation of GRB020603 (possible short/hard burst)
  17. GRB 020531 optical observations with TAROT
  18. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  19. IPN detection of possible bursts from SGR1806-20
  20. HST detection of the likely host galaxy of GRB 020124
  21. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  22. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  23. XRF 020427
  24. The end of BSAX GRB activities
  25. GRB 020124: Optical observations
  26. Mars Odyssey joins the IPN
  27. GRB020405: predicted break
  28. GRB 020409: No Evidence for an Optical Afterglow
  29. GRB 020409, 2nd epoch optical observations
  30. GRB 020331 Kyoto observation on March 31
  31. GRB 020409, No Optical Detection to R = 20
  32. BeppoSAX ALERT: possible GRB020411
  33. GRB 020409, optical observations
  34. BeppoSAX ALERT: possible GRB020410
  35. GRB020331 optical observations with RIMOTS
  36. GRB020124 optical observations with RIBOTS/RIMOTS
  37. GRB 020321: Candidate X-ray Counterparts
  38. ASM GRB candidate 020406 refined error box
  39. GRB 020331: Candidate Optical Afterglow
  40. Short RXTE/ASM transient 020406; may be a GRB
  41. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  42. IPN localization of GRB020405
  43. GRB 020331: NIR Observations
  44. GRB020331 NIR observation at KPNO (re-submission)
  45. GRB02033 NIR observation at KPNO
  46. GRB 020331, NIR observations
  47. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  48. GRB 020322: BeppoSAX observations of the X-ray afterglow
  49. SN 2002ap - peak brightness date (SN/GRB?)
  50. GRB 020322 optical observations
  51. GRB 011121: Fourth Epoch of HST Imaging
  52. GRB020321: a faint BeppoSAX detection
  53. GRB 020317 : KISO Optical Observations
  54. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  55. GRB 020305: Optical Observations
  56. GRB020317, optical observations
  57. GRB 011121: Third HST Epoch
  58. GRB 011121: HST Observations reveal an intermediate-time multicolor
  59. GRB011121, possible supernova association
  60. XRF/GRB 011030: Detection of the Probable Host Galaxy
  61. GRB020305, optical observations
  62. IPN triangulation of GRB020305 (HETE 1939)
  63. GRB020305 (=H1939): Localization of a GRB by HETE
  64. HST Imaging of the afterglow and host of GRB 011121
  65. IPN detection and localization of Cygnus X-1 flares
  66. RXTE Observations of SGR 1900+14
  67. IPN detection of further SGR1900+14 activity
  68. SGR1900+14 activity
  69. IPN/HETE Detection of Bursts from SGR1900+14
  70. IPN Upper Limits to a GRB Associated With SN2002ap
  71. GRB020127: Palomar and VLA Observations of Possible Counterparts
  72. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  73. SN2002ap (SN/GRB?) Echelle spectra
  74. GRB020127 Optical Observations
  75. SN2002ap (SN/GRB?) UBVRI Field Photometry
  76. GRB020127: Chandra Observations and Prospective Counterparts
  77. GRB020124, optical observations
  78. IPN detection of further activity from SGR1806-20
  79. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  80. GRB020124: Optical observations
  81. IPN observations of SGR1806-20
  82. GRB 020124: Optical afterglow
  83. GRB020124(=H1896): Localization of a Long GRB by HETE
  84. GRB 011211, spectrum and optical photometry
  85. GRB 011211: TNG Spectroscopic Observations
  86. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  87. GRB011130, optical observations
  88. GRB011130 (=XRF011130): Second Revised Localization by HETE
  89. GRB011130 (XRF011130) optical observations
  90. GRB011130 (=XRF011130): Revised Localization of an X-ray
  91. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  92. GRB 011121: J-band observations
  93. GRB011121
  94. GRB011030: Z-band observations
  95. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  96. GRB 970828: HST Observations of the Host Galaxy
  97. GRB 000131: HST Detection of the Host Galaxy
  98. GRB 970828: HST Observations of the Host Galaxy
  99. GRB010921, optical observation
  100. Optical observation of SGR 1806-20 at the 6-m SAO telescope

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