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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"

28059 results found.

  1. GRB 020410: Discovery of Probable OT by HST
  2. GRB 020124, HST observations of the fading afterglow
  3. IPN triangulation of GRB020708
  4. IPN triangulation of GRB020708
  5. Correction to IPN error box for GRB020706
  6. IPN triangulation of GRB020706
  7. GRB 020705: Optical observations
  8. GRB 020625, optical observations
  9. GRB 020625: Optical observations
  10. GRB 020531: optical photometry of Chandra sources
  11. GRB020625 (=H2081): A Long Burst Localized by HETE
  12. The Probable Host Galaxy of GRB/XRF 020427
  13. GRB/XRF 020427, detection of an underlying system with the VLT
  14. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  15. AXP 1E2259+586 optical observations
  16. Fading Optical Source in the Field of GRB020531
  17. GRB 020531, INT+WFC deep optical upper limits
  18. SGR-like Bursts from the AXP 1E 2259+586
  19. GRB020405: polarimetric observations
  20. GRB 020531, simultaneous optical observations
  21. GRB 020531/Candidate Redshift
  22. GRB020531: Detection of Candidate Host Galaxy
  23. GRB020531: Second epoch Chandra observations
  24. GRB020604, optical observations
  25. GRB020604, BVRcIc field photometry
  26. GRB020603, BVRcIc field observations
  27. GRB020531, BVRcIc field photometry
  28. GRB020531 Optical Observations
  29. GRB020531: Observations with the Chandra X-ray Observatory
  30. GRB020531, optical observations
  31. GRB020531: optical observations
  32. GRB020531(=H2042): Optical Observations
  33. GRB020531(=H2042): Optical Observations
  34. GRB020531: Optical observations
  35. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  36. GRB020525, optical observations
  37. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  38. XRF020427: Chandra Identification of a Likely X-ray Counterpart
  39. HST detection of the likely host galaxy of GRB 020124
  40. GRB020405 field photometry at ESO
  41. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  42. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  43. GRB020321 : Optical observations.
  44. XRF 020427
  45. GRB 020124: Optical observations
  46. IPN triangulation of GRB020418
  47. GRB020405: VLT observations of the OT environment
  48. IPN triangulation of GRB020413
  49. GRB020405: predicted break
  50. GRB 020409: No Evidence for an Optical Afterglow
  51. GRB 020331 Kyoto observation on March 31
  52. GRB020410: BeppoSAX NFI observation
  53. X-ray afterglow of GRB020321
  54. GRB020331 optical observations with RIMOTS
  55. GRB020124 optical observations with RIBOTS/RIMOTS
  56. GRB 020321: Candidate X-ray Counterparts
  57. GRB020406(?), optical observations
  58. GRB 020405: Decay index
  59. Short RXTE/ASM transient 020406; may be a GRB
  60. GRB020405, Radio Observations
  61. GRB 020405, U-band observations
  62. GRB011212: Optical Observations
  63. GRB 020331: NIR Observations
  64. GRB020331 NIR observation at KPNO (re-submission)
  65. GRB02033 NIR observation at KPNO
  66. GRB020331 field photometry
  67. GRB 020331, NIR observations
  68. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  69. GRB 020322: BeppoSAX observations of the X-ray afterglow
  70. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  71. Near-Infrared Observations of GRB020322 at TIRGO
  72. GRB 020321, Radio Observations
  73. GRB 020322: Optical Observations
  74. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  75. GRB 020321: Optical observations
  76. GRB020317 BVRI field photometry
  77. GRB011211 revised BVRI field photometry
  78. GRB020305 BVRI field photometry
  79. GRB020322 BVRI field photometry
  80. GRB 020322: Optical Sources and Improved Astrometry
  81. GRB020317: optical observations
  82. GRB020321 optical observations
  83. GRB020321: a faint BeppoSAX detection
  84. GRB 020317 : KISO Optical Observations
  85. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  86. GRB 020305: Optical Observations
  87. GRB020317, optical observations
  88. GRB 020317: Optical observations
  89. GRB 011121: Third HST Epoch
  90. GRB020305: Properties of the Candidate Optical Afterglow
  91. GRB 011121: HST Observations reveal an intermediate-time multicolor
  92. GRB011130 (XRF011130) Second Epoch Chandra Observations
  93. GRB020305: Subaru Optical Observations
  94. XRF/GRB 011030: Detection of the Probable Host Galaxy
  95. GRB 020305: Candidate optical afterglow
  96. GRB020305, optical observations
  97. IPN triangulation of GRB020305 (HETE 1939)
  98. GRB020305 (=H1939): Localization of a GRB by HETE
  99. HST Imaging of the afterglow and host of GRB 011121
  100. IPN detection and localization of Cygnus X-1 flares

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