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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"

24603 results found.

  1. Single IPN error box for GRB020904
  2. XRF 020903: optical observation at Kyoto
  3. GRB020322 : HST/STIS observations
  4. XRF 020903: Optical observations
  5. IPN triangulation of GRB020904
  6. INTEGRAL GRBs added to GCN
  7. SGR1900+14 burst localized by HETE
  8. GRB020813: High-resolution optical spectroscopy
  9. GRB020812: negative optical observations
  10. GRB 020812: optical observation at Kyoto University
  11. Second epoch K band imaging of GRB 020819
  12. GRB 020813 : HST observations
  13. GRB 020812: early time optical observation at Ouda Station
  14. GRB020813: Magellan BVRI Photometry
  15. GRB 020819: Optical observations
  16. K band observation of GRB 020819
  17. GRB020813: optical and NIR observations
  18. GRB020813: Fading X-ray Afterglow Observed with Chandra
  19. GRB020813, UBVRI field calibration
  20. GRB020812: NIR observations
  21. Polarimetry of GRB020813: evidence for variability
  22. GRB020813 IRAM millimeter observations
  23. GRB020812: optical observations
  24. GRB020813: High-Resolution Optical Observations
  25. GRB 020812: optical observation at Bisei
  26. GRB020813: Early Time Magnitude
  27. Millimeter observation of GRB 020813
  28. GRB020812: optical observations
  29. GRB 020813 : KISO multiband optical observations
  30. GRB020813, optical observations
  31. IPN error box for GRB020813
  32. GRB020813, astrometric position
  33. Spectropolarimetry of GRB 020813
  34. GRB 020812 optical observation
  35. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  36. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  37. HST Imaging of the Host of GRB 011121
  38. GRB020801, optical afterglow candidate
  39. GRB020331: Late-time Optical Light Curve (re-submission)
  40. GRB020331: Late-time Optical Light Curve
  41. IPN triangulation of GRB020714
  42. IPN triangulation of GRB020715 (=GRB150702)
  43. IPN triangulation of GRB020714
  44. IPN triangulation of GRB150702
  45. GRB 020410: Discovery of Probable OT by HST
  46. GRB 020124, HST observations of the fading afterglow
  47. IPN triangulation of GRB020708
  48. IPN triangulation of GRB020708
  49. Correction to IPN error box for GRB020706
  50. IPN triangulation of GRB020706
  51. GRB 020705: Optical observations
  52. GRB 020625, optical observations
  53. GRB 020625: Optical observations
  54. GRB 020531: optical photometry of Chandra sources
  55. GRB020625 (=H2081): A Long Burst Localized by HETE
  56. The Probable Host Galaxy of GRB/XRF 020427
  57. GRB/XRF 020427, detection of an underlying system with the VLT
  58. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  59. AXP 1E2259+586 optical observations
  60. Fading Optical Source in the Field of GRB020531
  61. GRB 020531, INT+WFC deep optical upper limits
  62. SGR-like Bursts from the AXP 1E 2259+586
  63. GRB020405: polarimetric observations
  64. GRB 020531, simultaneous optical observations
  65. GRB 020531/Candidate Redshift
  66. GRB020531: Detection of Candidate Host Galaxy
  67. GRB020531: Second epoch Chandra observations
  68. GRB020604, optical observations
  69. GRB020604, BVRcIc field photometry
  70. GRB020603, BVRcIc field observations
  71. GRB020531, BVRcIc field photometry
  72. GRB020531 Optical Observations
  73. GRB020531: Observations with the Chandra X-ray Observatory
  74. GRB020531, optical observations
  75. GRB020531: optical observations
  76. GRB020531(=H2042): Optical Observations
  77. GRB020531(=H2042): Optical Observations
  78. GRB020531: Optical observations
  79. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  80. GRB020525, optical observations
  81. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  82. XRF020427: Chandra Identification of a Likely X-ray Counterpart
  83. HST detection of the likely host galaxy of GRB 020124
  84. GRB020405 field photometry at ESO
  85. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  86. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  87. GRB020321 : Optical observations.
  88. XRF 020427
  89. GRB 020124: Optical observations
  90. IPN triangulation of GRB020418
  91. GRB020405: VLT observations of the OT environment
  92. IPN triangulation of GRB020413
  93. GRB020405: predicted break
  94. GRB 020409: No Evidence for an Optical Afterglow
  95. GRB 020331 Kyoto observation on March 31
  96. GRB020410: BeppoSAX NFI observation
  97. X-ray afterglow of GRB020321
  98. GRB020331 optical observations with RIMOTS
  99. GRB020124 optical observations with RIBOTS/RIMOTS
  100. GRB 020321: Candidate X-ray Counterparts

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