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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"

24612 results found.

  1. Radio Observations of XRF 020903: The Missing Link
  2. XRF 020903: Supernova
  3. IPN triangulation of GRB020923 (two error boxes)
  4. IPN triangulation of GRB020914B
  5. IPN triangulation of GRB020911 (2 large error boxes)
  6. GRB 020305: HST/STIS observations
  7. Confirmation of IPN error box for GRB020910
  8. IPN triangulation of GRB020910
  9. IPN GCN Circulars now to be issued without restriction
  10. Single IPN error box for GRB020904
  11. XRF 020903: optical observation at Kyoto
  12. GRB020322 : HST/STIS observations
  13. XRF 020903: Optical observations
  14. IPN triangulation of GRB020904
  15. INTEGRAL GRBs added to GCN
  16. SGR1900+14 burst localized by HETE
  17. GRB020813: High-resolution optical spectroscopy
  18. GRB020812: negative optical observations
  19. GRB 020812: optical observation at Kyoto University
  20. Second epoch K band imaging of GRB 020819
  21. GRB 020813 : HST observations
  22. GRB 020812: early time optical observation at Ouda Station
  23. GRB020813: Magellan BVRI Photometry
  24. GRB 020819: Optical observations
  25. K band observation of GRB 020819
  26. GRB020813: optical and NIR observations
  27. GRB020813: Fading X-ray Afterglow Observed with Chandra
  28. GRB020813, UBVRI field calibration
  29. GRB020812: NIR observations
  30. Polarimetry of GRB020813: evidence for variability
  31. GRB020813 IRAM millimeter observations
  32. GRB020812: optical observations
  33. GRB020813: High-Resolution Optical Observations
  34. GRB 020812: optical observation at Bisei
  35. GRB020813: Early Time Magnitude
  36. Millimeter observation of GRB 020813
  37. GRB020812: optical observations
  38. GRB 020813 : KISO multiband optical observations
  39. GRB020813, optical observations
  40. IPN error box for GRB020813
  41. GRB020813, astrometric position
  42. Spectropolarimetry of GRB 020813
  43. GRB 020812 optical observation
  44. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  45. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  46. HST Imaging of the Host of GRB 011121
  47. GRB020801, optical afterglow candidate
  48. GRB020331: Late-time Optical Light Curve (re-submission)
  49. GRB020331: Late-time Optical Light Curve
  50. IPN triangulation of GRB020714
  51. IPN triangulation of GRB020715 (=GRB150702)
  52. IPN triangulation of GRB020714
  53. IPN triangulation of GRB150702
  54. GRB 020410: Discovery of Probable OT by HST
  55. GRB 020124, HST observations of the fading afterglow
  56. IPN triangulation of GRB020708
  57. IPN triangulation of GRB020708
  58. Correction to IPN error box for GRB020706
  59. IPN triangulation of GRB020706
  60. GRB 020705: Optical observations
  61. GRB 020625, optical observations
  62. GRB 020625: Optical observations
  63. GRB 020531: optical photometry of Chandra sources
  64. GRB020625 (=H2081): A Long Burst Localized by HETE
  65. The Probable Host Galaxy of GRB/XRF 020427
  66. GRB/XRF 020427, detection of an underlying system with the VLT
  67. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  68. AXP 1E2259+586 optical observations
  69. Fading Optical Source in the Field of GRB020531
  70. GRB 020531, INT+WFC deep optical upper limits
  71. SGR-like Bursts from the AXP 1E 2259+586
  72. GRB020405: polarimetric observations
  73. GRB 020531, simultaneous optical observations
  74. GRB 020531/Candidate Redshift
  75. GRB020531: Detection of Candidate Host Galaxy
  76. GRB020531: Second epoch Chandra observations
  77. GRB020604, optical observations
  78. GRB020604, BVRcIc field photometry
  79. GRB020603, BVRcIc field observations
  80. GRB020531, BVRcIc field photometry
  81. GRB020531 Optical Observations
  82. GRB020531: Observations with the Chandra X-ray Observatory
  83. GRB020531, optical observations
  84. GRB020531: optical observations
  85. GRB020531(=H2042): Optical Observations
  86. GRB020531(=H2042): Optical Observations
  87. GRB020531: Optical observations
  88. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  89. GRB020525, optical observations
  90. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  91. XRF020427: Chandra Identification of a Likely X-ray Counterpart
  92. HST detection of the likely host galaxy of GRB 020124
  93. GRB020405 field photometry at ESO
  94. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  95. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  96. GRB020321 : Optical observations.
  97. XRF 020427
  98. GRB 020124: Optical observations
  99. IPN triangulation of GRB020418
  100. GRB020405: VLT observations of the OT environment

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